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Biology is a study of living objects and their life processes. It examines all aspects of living organisms such as their occurrence, classification, internal and external structure, nutrition, reproduction, inheritance, etc. The term “biology” is commonly replaced by the terms “life sciences” and “biological sciences.” There are dozens of branches of biology. Some of the major ones include:

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Abstract

Soluble dietary fibre (SDF) is well recognised for its remarkable effectiveness in promoting human health. This study utilised response surface methodology to evaluate the optimal conditions required to extract SDF (U-SDF) from Lentinula edodes via the ultrasonic-assisted hot-water method, and evaluated the hypolipidemic effects and anti-inflammatory effects of U-SDF. The optimal extraction conditions for U-SDF were ultrasonic power of 182 W, extraction time of 2 h, extraction temperature of 81 °C, and solid-liquid ratio of 1:24 (g mL−1). Under these conditions, the extraction rate of U-SDF reached 8.08%. U-SDF treatment significantly improved liver and kidney indices in diabetic mice, markedly reduced the levels of plasma triglycerides (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and significantly increased the level of high-density lipoprotein-cholesterol (HDL-C) in a dose-dependent manner. U-SDF also improved adipose tissue injury in diabetic mice, significantly decreased the levels of cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumour necrosis factor-α (TNF-α), and alleviated inflammation of the abdominal aorta. In conclusion, U-SDF from L. edodes is an excellent source of dietary fibres, which exhibit good hypolipidemic and anti-inflammatory activities, suggesting potential applications as a functional additive in diverse food products.

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Abstract

Food industrial bacterial cells eliminate aflatoxin M1 (AFM1) at different ratios. The study aimed to investigate the effect of AFM1 on probiotic industrial bacteria (Lactococcus lactis ssp. lactis R703, Bifidobacterium animalis ssp. lactis BB12, and L. paracasei subsp. paracasei 431) and evaluating their AFM1 binding ability in naturally contaminated milk. The growth of the R703 strain was affected by AFM1 at 1.47 μg L−1 concentration. Peptidoglycan (PG) cell wall fractions of R703 and BB12 bound a significant amount of AFM1 from naturally contaminated milk under one-hour treatment, while L. paracasei 431 was not effective. PG was better absorbent for AFM1 than viable cells of BB12, while the difference was insignificant for the R703 strain. Increasing the time did not significantly change the mycotoxin binding of BB12, while for R703 PG the absorption seemed reversible. BB12 PG needs further analysis for biotechnological application in dairy products.

Open access

Abstract

The aim of this work was to microencapsulate propolis phenolic compounds using polycaprolactone as wall material by double emulsion solvent evaporation (w1/o/w2). Microencapsulation experiments were carried out by investigating the effect of sample/solvent ratio (10–100 mg mL−1), poly(ε-caprolactone) (PCL) concentrations (200–1,000 mg mL−1), poly(vinyl alcohol) (PVA) concentrations (0.5–2.5 g mL−1), and stirring speed (200–1,000 r.p.m.) on the microencapsulation efficiency of total phenolic content (TPC%) and antioxidant activity of propolis. The best microencapsulation conditions were selected according to the total phenolic amount and their antioxidant activity. Experimental results showed that all microencapsulation conditions had significant effects (P < 0.05) on total phenolic content and antioxidant activities. The best conditions were: 30 mg mL−1, 600 mg mL−1, 2 g mL−1, and 400 r.p.m. for sample/solvent ratio, PCL concentrations, PVA concentrations, and stirring speed, respectively, with values of 86.98 ± 0.03% for phenolic encapsulation efficiency, 53.81 ± 0.50% for free radical scavenging activity (DPPH), and 45,480 Trolox equivalent, mg TE/100 g dry weight for ferric reducing antioxidant power (FRAP). Under all encapsulation conditions, a significant positive correlation was observed between ferric reducing antioxidant power, free radical scavenging activity, and phenolic content.

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Acta Alimentaria
Authors:
C.V. Raimundi
,
B.C. Scopel
,
A.N. Ito
,
A.A.L. Tribst
,
G.A.R. Sehn
,
D. Cavalheiro
, and
E. Rigo

Abstract

The effects of milk from different species (sheep/cow) and pH adjustment in the production of Requeijão cremoso, a kind of processed cheese, were investigated. The results showed that the sheep's Requeijão cremoso had higher pH (∼3%), lower yellowness index (∼11%), and lower brightness (∼12%) after 5 days of storage, and at least 40% lower hardness compared to the Requeijão made from cow milk. The pH adjustment did not change the visual appearance of the samples but affected their hardness in different ways, with an increase of up to 16% for the cheese from cow milk and a reduction of up to 39% for the cheese produced from sheep milk. The results suggested that the protein-protein interactions were favoured in the Requeijão cremoso from sheep milk, while a protein network with higher water holding capacity and increased hardness was observed for the samples from cow milk.

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Abstract

This work used a carrageenan-based thrombosis model to determine the preventative effects of Lactobacillus plantarum YS1 (LPYS1) on thrombus. In thrombotic mice, LPYS1 improved the activated partial thromboplastin time (APTT), while decreasing the thrombin time (TT), prothrombin time (PT), and fibrinogen (FIB) content. In thrombotic mouse serum, LPYS1 decreased the levels of malondialdehyde (MDA), tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), nuclear factor kappa-B (NF-κB), and interleukin-1 beta (IL-1β), while also increasing the activities of superoxide dismutase (SOD) and catalase (CAT). Moreover, LPYS1 upregulated the mRNA expression levels of copper/zinc-SOD (Cu/Zn-SOD), manganese-SOD (Mn-SOD), and CAT in the colon tissues of thrombotic mice, while downregulating those of NF-κB p65, IL-6, TNF-α, and interferon-gamma (IFN-γ) mRNA. In tail vein vascular tissues, LPYS1 suppressed the mRNA expression levels of NF-κB p65, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin. The abundances of both beneficial and pathogenic bacteria were altered by LPYS1. These findings show that LPYS1 has the capacity to protect mice from thrombosis, while also revealing some of the underlying mechanisms of this effect.

Open access

Abstract

The activity and structural variation of glycogen phosphorylase (GP) at different phosphorylation levels during incubation at 4 °C were explored in this study. The GP was assigned into four treatments to obtain high/low phosphorylation levels, which were (1) treated with glycogen phosphorylase kinase (Phk) to obtain high phosphorylation level, (2) treated with protein kinase A to obtain high phosphorylation level, (3) treated with alkaline phosphatase to obtain low phosphorylation level, and (4) control. Compared with the control group, the content of α-helix and β-sheet increased and the secondary structure of GP changed from disorder to order after phosphorylation. The activity of GP was increased and its structure was more tightly in the Phk group than that in the control group. The phosphorylation at Ser277, Ser430, Ser809, Thr304, Tyr298, and Tyr525 resulted in tighter spatial structure. In conclusion, phosphorylation of GP enhanced its catalytic activity by making the secondary and spatial structure more orderly, which is of great significance for controlling meat quality by regulating glycolysis.

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Acta Alimentaria
Authors:
M. Chaalal
,
S. Ydjedd
,
L. Chemache
,
R. López-Nicolás
,
T. Sánchez-Moya
,
C. Frontela-Saseta
,
G. Ros-Berruezo
, and
D.E. Kati

Abstract

Carob pulp is a natural source of polyphenols, which have been shown to possess health benefits. These compounds play a crucial role in initiating, shaping, and modulating the gut microbiota. The objective of this study was to evaluate the impact of carob pulp phenolic extracts on nine specific groups of human gut microbiota before and after in vitro gastrointestinal digestion. The effects of pure gallic and coumaric acids were also tested. The results showed that the treated phenolic compounds exhibited inhibitory effects on the growth of most pathogenic bacteria. Gallic acid, in particular, demonstrated the most potent antimicrobial effect on Listeria monocytogenes, reducing its growth to below 5%. Staphylococcus aureus and Escherichia coli showed a growth reduction of up to 10%. Furthermore, both phenolic acids, before and after digestion, led to a slight reduction in E. coli O157:H7 numbers. Probiotic bacteria experienced minimal decrease following exposure to phenolic extracts. However, the growth of Lactobacillus casei ssp. rhamnosus was significantly inhibited by almost 50%. Interestingly, the in vitro digestion process exhibited a stronger antibacterial effect against pathogenic bacteria compared to probiotic bacteria. These results highlight the potential of carob phenolic extracts in modulating the intestinal microbiota, thereby offering interesting prospects for the development of diet-based health strategies.

Open access
European Journal of Microbiology and Immunology
Authors:
Vishwa A. Khatri
,
Sambuddha Paul
,
Niraj Jatin Patel
,
Sahaja Thippani
,
Janhavi Y. Sawant
,
Katie L. Durkee
,
Cassandra L. Murphy
,
Geneve Ortiz Aleman
,
Justine A. Valentino
,
Jasmine Jathan
,
Anthony Melillo
, and
Eva Sapi

Abstract

The bacterial spirochete Borrelia burgdorferi, the causative agent of Lyme Disease, can disseminate and colonize various tissues and organs, orchestrating severe clinical symptoms including arthritis, carditis, and neuroborreliosis. Previous research has demonstrated that breast cancer tissues could provide an ideal habitat for diverse populations of bacteria, including B. burgdorferi, which is associated with a poor prognosis. Recently, we demonstrated that infection with B. burgdorferi enhances the invasion and migration of triple-negative MDA-MB-231 cells which represent a type of breast tumor with more aggressive cancer traits. In this study, we hypothesized that infection by B. burgdorferi affects the expression of cancer-associated genes to effectuate breast cancer phenotypes. We applied the high-throughput technique of RNA-sequencing on B. burgdorferi-infected MDA-MB-231 breast cancer and normal-like MCF10A cells to determine the most differentially expressed genes (DEG) upon infection. Overall, 142 DEGs were identified between uninfected and infected samples in MDA-MB-231 while 95 DEGs were found in MCF10A cells. A major trend of the upregulation of C-X-C and C-C motif chemokine family members as well as genes and pathways was associated with infection, inflammation, and cancer. These genes could serve as potential biomarkers for pathogen-related tumorigenesis and cancer progression which could lead to new therapeutic opportunities.

Open access

Abstract

Infections caused by Staphylococcus aureus are currently a worldwide threat affecting millions of individuals. The pathogenicity of S. aureus is associated with numerous virulence factors, including cell surface proteins, polysaccharides, and secreted toxins. The pore-forming α-hemolysin, known as α-toxin, is produced by nearly all virulent strains of S. aureus and is implicated in several diseases including skin and soft tissue infections, atopic dermatitis, and pneumonia. There are currently no vaccines available for the prevention of S. aureus infections and the efficacy of available antibiotics has been fading. In this study we examined the mode of antihemolytic activity of theaflavin-3,3′-digallate against α-hemolysin of methicillin-resistant S. aureus by molecular docking using AutoDock Vina as the molecular docking tool. The theaflavin-3,3′-digallate docked the molecular sequence of the Hla (PDB ID:7ahl). The scores of the top 10 binding modes obtained were between −9.0 and −8.5 kcal mol−1, and the best binding mode was −9.0 kcal mol−1. Direct binding sites of theaflavin-3,3′-digallate to the “stem” domain of Hla were revealed which primarily targeted of the residues Met113, Thr117, Asn139. The disclosure of this potential binding mode warrants further clinical evaluation of theaflavin-3,3′-digallate as an anti-hemolytic compound in order to practically validate our results.

Open access

Abstract

Potato mulching practices and their effects often differ, and the results are sometimes contradictory in the literature, as they vary depending on climatic conditions and growing practices. In this study, we analysed 68 peer-reviewed publications to reveal which problems of potato cultivation were intended to be solved by mulching with organic materials. We have found that the main goals of mulching are the preservation of soil moisture, the reduction of soil temperature, and the suppression of weeds, in which mulching provides effective help. In different parts of the world, different organic mulches increased the yield of potatoes in 78% of the studies. Although the occurrence and damage of pests, pathogens and weeds are extremely understudied (16, 18, 29% of the studies), we can conclude that organic mulches effectively reduced their damage.

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Abstract

Effect of edible coatings based on zedo gum (ZG) containing thyme (Thymus vulgaris) essential oil (TEO) and cinnamon (Cinnamomum verum) extract (CAE) on the quality and proteolysis of cheddar cheese was investigated. Four treatments were prepared using different coating formulas including: C (coated cheese with paraffin and wax mixture as commercial coating), Z treatment (coated cheese with ZG solution), TEO treatment (coated cheese with TEO), and CAE treatment (coated cheese with CAE). The results showed that the highest moisture content and proteolysis indices were related to sample C; the lowest moisture content and number of starter lactic acid bacteria (SLAB) and the highest protein content, FDM content, proteolysis indices and number of non-starter lactic acid bacteria (NSLAB) were related to sample Z; while the TEO and CAE treatments showed similar values. Also, TEO and CAE had an inhibitory effect on growth of moulds and yeasts, without affecting NSLAB and SLAB. Therefore, instead of commercial coating, zedo gum containing T. vulgaris essential oil or C. verum extract can be used as active coating on cheddar cheese.

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Abstract

In this study, we compile the findings to date on using several cellulose-based materials as adsorbents of potentially toxic elements (PTEs) from wastewater. Furthermore, this review discussed the destiny of PTEs-loaded cellulose-based adsorbents and some sustainable methods for their management, hoping to close the pollution loop.

Open access
Acta Phytopathologica et Entomologica Hungarica
Authors:
Josepha El Chami
,
Elias El Chami
,
Ákos Tarnawa
,
Katalin Maria Kassai
,
Zoltán Kende
, and
Márton Jolánkai

Abstract

Wheat is a cereal of special importance in the world cereal production. Fusarium head blight is one of the most important diseases of wheat caused by phytopathogenic Fusarium species that significantly reduce wheat production. This disease reduces grain yield and quality and causes the presence of harmful mycotoxins. The purpose of this study is to test the effect of Fusarium infection on wheat quality parameters in two wheat varieties Alföld and Mv Karéj. The results showed that Fusarium infection was higher in 2021 (91.47% and 95.20%) compared to 2020 (44.33% and 40.27%) in the two wheat varieties used Alföld and Mv Karéj respectively. In Alföld, Fusarium infection had a negative effect on protein content, test weight, thousand kernel weight, gluten content and Zeleny sedimentation index, whereas falling number was not affected. In Mv Karéj, Fusarium infection had a negative effect on test weight, thousand kernel weight, falling number and Zeleny sedimentation index, whereas protein content and gluten content were not affected. Although Fusarium infection reduced wheat quality, Mv Karéj showed a stable protein and gluten content whereas Alföld showed a stable falling number. Thus, Mv Karéj is more tolerant to Fusarium infection compared to Alföld.

Open access

Abstract

The main objectives of the present study were to investigate the physical attributes and chemical characteristics of dried apple cubes. The apple cubes were dried in vacuum and infrared dryers at 40 °C and freeze dryer individually and in combination. The physical properties – texture and rehydration – of vacuum drying-assisted freeze-dried apple dices were close to the freeze-dried products. The hardness of vacuum drying-assisted freeze-dried apples was better, by at least 15.8%, than those dried by infrared-freeze, but rehydration capacities were similar. The freeze-dried control samples achieved a lower water activity (0.145) in comparison with infrared, vacuum, and combined dried ones. The infrared-freeze-dried samples retained 3.6 and 11.6% more polyphenols and antioxidant capacity than samples prepared by the other methods. The ascorbic acid content of the freeze-dried samples was significantly higher by about 59% than that of the hybrid dried samples.

Open access

Abstract

The popularity of sweet potatoes in Central Europe has been increasing recently, mainly the high-quality, perfect, fresh tubers are in demand. However, out of class grade tubers could be marketed in dried, grounded form as sweet potato flour.

The aim of this study was to characterise some important nutritional properties of flours of three sweet potato genotypes with different tuber colours (white, purple, and orange) and to investigate how this raw material affects the rheological properties of sweet potato-wheat flour blends.

Dietary fibres are present in sweet potatoes in a significant proportion, orange coloured flour showed the highest values. The main free sugars were sucrose, glucose, and fructose, but sucrose was the dominant one. Antioxidant capacity and total phenolic content also varied considerably, the purple flour had the highest values. Mineral composition showed significant variability, the purple flour contained the highest level of minerals. It was confirmed that adding sweet potato flour to wheat flour affected its rheological properties, however in a varied manner. For the orange flour these properties have lightly decreased, though it had no significant effect on dough quality, while the white and purple flours with a dosage of 5, 10 and 15% could improve the dough behaviour. Thus, sweet potato in this form is a valuable raw material.

Open access

Abstract

The aim of our research was to study the water and ethanol extractable polyphenols of stinging nettle (Urtica dioica L.) harvested in different seasons and to determine their antimicrobial activity against certain human pathogenic and food spoiling bacteria and yeasts.

Our results indicate that the spring leaf extracts had higher polyphenol contents than the root one; however, close to the end of the vegetation period these values decreased considerably in both leaves and roots. Detection and quantification of the most abundant phenolic compounds in the spring extracts by HPLC revealed the occurrence of 12 different phenol carboxylic acids and flavonoids. Flavonoid compounds were more abundant than phenol carboxylic acids in the leaves; however, their proportion was equal in the case of the roots. Nettle leaf extracts had remarkable antimicrobial activity, the spring extracts were more efficient than the autumn ones. Escherichia coli and Staphylococcus aureus were sensitive to every leaf extract, while Listeria monocytogenes and Pseudomonas aeruginosa had reduced but remarkable sensitivity patterns. Among the yeasts, Candida glabrata was strongly inhibited by the aqueous leaf extracts. Most of the strains were insensitive to the root extracts, although Enterococcus faecalis was inhibited by the root and not the leaf extracts.

Open access

Abstract

As a principal pigment in plants, chlorophyll a (Chl a) is widely used to evaluate quality changes and senescence process during storage of leafy vegetables. The determination of Chl a in plant extracts by spectrophotometric methods using various empirical equations is often unreliable. Considering the sensitivity of fluorescence detection, we report here a simple, inexpensive spectrofluorimetric method that can detect and quantify Chl a in plant extracts. The fluorescence standard used for the quantitative determination of Chl a was isolated in our laboratory from the extract of Anthrospira platensis (Spirulina). The method proved to be reliable, fast, and low cost in a study of the influence of the most commonly used domestic storage conditions on Chl a degradation in fresh-cut arugula.

Restricted access
European Journal of Microbiology and Immunology
Authors:
Kirsten Alexandra Eberhardt
,
Luzia Veletzky
,
Felix Weinreich
,
Richard Odame Phillips
,
Fred Stephen Sarfo
,
Torsten Feldt
,
Albert Dompreh
,
Shadrack Osei Asibey
,
Richard Boateng
, and
Hagen Frickmann

Abstract

Background

Mansonellosis is a widely neglected helminth disease which is predominantly observed in tropical regions. This study was conducted to assess potential associations of the prevalence of circulating Mansonella perstans-specific cell-free DNA in human serum and HIV infection in Ghanaian individuals.

Methods

For this purpose, serum samples obtained from Ghanaian HIV-patients (n = 989) and non-HIV-infected Ghanaian control individuals (n = 91) were subjected to real-time PCR targeting the ITS-(internal transcribed spacer-)2 sequence of M. perstans and Mansonella sp. Deux.

Results

Mansonella-specific cell-free DNA was detected in serum samples of only 2 HIV-positive and 0 HIV-negative individuals, making any reliable conclusions on potential associations between HIV and mansonellosis in tropical Ghana unfeasible.

Conclusions

Future epidemiological studies on hypothetical associations between mansonellosis and HIV infections should focus more specifically on high-endemicity settings for both Mansonella spp.-infections and HIV-infections, include higher case numbers and be based on real-time PCR from whole blood rather than from serum, in which only circulating parasite DNA but no more cell-bound parasite DNA can be detected. However, the study did not show associations of HIV infections in Ghanaian individuals with Mansonella worm loads high enough to detect cell-free Mansonella DNA in serum by PCR.

Open access
European Journal of Microbiology and Immunology
Authors:
Bianca Kelly Neves Izidro da Silva
,
Ana Cláudia Alves Cortez
,
Luciana Aires Oliveira
,
Juan Diego Ribeiro de Almeida
,
Érica Simplício de Souza
,
Katia Santana Cruz
,
Ani Beatriz Jackisch Matsuura
,
Mauricio Morishi Ogusku
,
Karolina Jeaneth Solórzano Chavarría
,
Djane Baía-da-Silva
,
Quique Bassat
,
Marcus Vinícius Guimarães Lacerda
,
Hagen Frickmann
, and
João Vicente Braga de Souza

Abstract

Background

This study aimed at improving a real-time polymerase-chain-reaction (qPCR) assay for the detection of Histoplasma capsulatum, a fungal pathogen that can cause severe respiratory infections in humans, in clinical and soil samples.

Methods

Primer and probes were in-silico designed, in-silico and in-vitro evaluated including clinical biopsy materials and finally subjected to a real-world application with collected soil samples.

Results

Applying the qPCR assay with liver and lung biopsies from 71 patients each, including 59 patients infected with human immunodeficiency virus (HIV), as well as with Sabouraud (SAB) agar culture as the diagnostic reference standard, diagnostic accuracy of the qPCR assay of 100% (5/5) sensitivity and 96% (63/66) specificity for liver samples and 100% (4/4) sensitivity and 94% (63/67) specificity for the lung samples was recorded. When applying the assay with soil samples from caves near of Presidente Figueiredo city, Amazonas, Brazil, one sample from the Maroaga cave was confirmed as positive.

Conclusions

The improved qPCR assessed in this study was successful in detecting H. capsulatum with high efficiency and accuracy in in-vitro evaluation, including the identification of the target pathogen in both clinical and environmental samples.

Open access

Abstract

In our study, using a combination of eye-tracking parameter analysis and the van Westendorp method, we investigate whether participants pay more attention to products that they perceive as more expensive or to those that they prefer in the ranking process. The experiment involved 50 participants, a questionnaire with ranking and pricing tasks, and an eye-tracking measurement. Three wine varieties (Irsai Olivér, Rosé and Merlot-Shiraz) and three different label alternatives were tested. When comparing the results of the ranking and the pricing tasks, the product that is considered more expensive is not always the one that is most appealing to the participants. If we compare the results from the analysis of the eye-tracking parameters and the pricing, we can say that in all cases the labels that received the most visual attention were those that were priced more expensively by the participants.

Open access
Acta Alimentaria
Authors:
Sz. Luzics
,
Á. Tóth
,
T. Barna
,
E. Szabó
,
I. Nagy
,
B. Horváth
,
I. Nagy
,
Z. Varecza
,
I. Bata-Vidács
, and
J. Kukolya

Abstract

Thermobifida alba is the mesophilic member of the Thermobifida genus, the genome and enzyme sets of which have not been described and published yet. Thermobifida strains are thermotolerant actinomycete, which possess wide sets of cellulose and hemicellulose hydrolysing enzymes. Previously, three endomannanases (Man5ATh, Man5ATc, and Man5AThf) of thermobifidas were cloned and investigated, and hereby the endomannanase of T. alba DSM 43795 is described. All four endomannanases belong to the glycoside hydrolase family 5, their sizes are around 50–55 kDa. Their structure consists of a catalytic domain and a carbohydrate binding module, while there is an interdomain linker region in-between consisting repetitive tetrapeptide motifs (eg.: PPTEPTD-Ta, PTDP-Tc, TEEP-Tf, DPGT-Th). The pH optima of Man5A enzymes from T. alba, Thermobifida halotolerans, Thermobifida cellulosilytica, and Thermobifida fusca are slightly different (6.5, 7.0, 7.5, and 8.0, respectively), however, the temperature optima of the enzymes were detected within a wider range of 65–75 °C. In this research, Man5ATa exhibited the lowest Michaelis-Menten constant (KM) (0.13 mM) on LBG-mannan substrate, while others shared similar kinetic parameters: 0.9–1.7 mM of KM. Despite the high sequence similarity of the investigated mannanases, they exhibit different temperature stability parameters. These different functional characteristics can be advantageous for industrial applications producing biologically active, oligomannan prebiotics under different conditions.

Open access

Abstract

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS) characterized by inflammation and neurodegeneration. Current research suggests that diet may influence disease course, severity of symptoms, and quality of life in MS patients. The ketogenic diet (KD) has been used for more than a century as a therapeutic approach for various medical conditions. It was originally developed in the 1920s as a treatment option for epilepsy, and especially in the last 30 years, has gained popularity for its potential benefits in a variety of neurological conditions other than epilepsy. This prompted us to perform a literature survey regarding the effect of KD on the onset and progression of MS. The here reviewed 15 original research articles including in vitro, preclinical, and clinical studies provide evidence for the safety and feasibility of the KD in MS, showing potential neuroprotective effects and positive impacts on cellular metabolism and disease outcome. Since the literature is limited and most studies were conducted with low numbers of MS patients and rather exploratory in nature, further studies with larger cohorts are needed to gain a better understanding of the mechanisms by which the improvements of the MS disease course are achieved.

Open access

Abstract

The prevalence of Campylobacter jejuni infections is increasing worldwide and responsible for significant morbidities and socioeconomic expenses. The rise in antimicrobial resistance of C. jejuni underscores the urge for evaluating antibiotics-independent compounds as therapeutic and preventive treatment options of human campylobacteriosis. Given its well-known anti-microbial and immune-modulatory properties we here surveyed the disease-modifying effects of trans-cinnamaldehyde pretreatment in experimental campylobacteriosis. Therefore, secondary abiotic IL-10−/− mice were orally challenged with trans-cinnamaldehyde starting 7 days prior C. jejuni infection. Whereas gastrointestinal colonization properties of the enteropathogens remained unaffected, trans-cinnamaldehyde pretreatment did not only improve clinical signs in infected mice, but also alleviated colonic epithelial cell apoptosis on day 6 post-infection. Furthermore, trans-cinnamaldehyde application resulted in less pronounced T cell responses in the colon that were accompanied by dampened proinflammatory mediator secretion in distinct intestinal compartments. Notably, the immune-modulatory effects of trans-cinnamaldehyde were not restricted to the intestinal tract but could also be observed in extra-intestinal organs such as the liver and kidneys. In conclusion, our preclinical placebo-controlled intervention study provides first evidence that due to its immune-modulatory effects, trans-cinnamaldehyde constitutes a promising prophylactic option to alleviate campylobacteriosis.

Open access
Acta Phytopathologica et Entomologica Hungarica
Authors:
Souhila Boubetra
,
Bilal Yahiaoui
,
Arezki Lehad
,
Moussa Mokhtari
,
Rima Hind Boudchicha
,
Farida Mohammedi
,
Roza Assous
, and
Meriem Louanchi

Abstract

Cereals are prone to viral infections and the economic impact of these has increased in recent years. Among these diseases barley yellow dwarf (BYD) is one of the most destructive diseases of cereals today. For three consecutive years (2014–2015–2016) surveys were carried out in order to search for BYDV species (BYDV-PAV and -MAV) as well as other cereal viruses, wheat spindle streak mosaic virus (WSSMV), southern bean mosaic virus (SBMV) and barley stripe mosaic virus (BSMV) in seven regions of Algeria (Algiers, Boumerdes, Tipaza Médéa, Adrar, Khenchla and Batna).

Targeted samples were taken randomly from plants of different cereal species (wheat, barley, oats). The sample were analyzed by DAS-ELISA and RT-PCR.

The results of ELISA and PCR tests showed the presence of BYDV-PAV in barley, durum wheat, soft wheat and oats. Thus, this viral species were found in all the cereal regions surveyed (North, South, East and West).

Seven samples (durum wheat, barley and oats) were sequenced and phylogenetic analyses performed revealed that the Algerian sequences clustered in group I and group II.

Restricted access
Acta Phytopathologica et Entomologica Hungarica
Authors:
Barbara Katalin Szabó
,
Klaudia Dóra Molnár
,
Sára Dóra Vlaskality
, and
Katalin Körösi

Abstract

In our study, we examined mycotoxin-producing fungi found in sorghum grains (Sorghum bicolor L. Moench). During the experiment, the internal infection of grains was examined on 3 different selective culture media, as individual literature differs as to which selective culture media are the most suitable for the isolation of Fusarium species under laboratory conditions (Leslie and Summerell, 2006). During our experiments, we also used molecular methods to identify the selected Fusarium species down to the species level. In the case of Fusarium species our experiment shows that the best media is Nash & Snyder media. During the morphological identification we worked with 18 Fusarium monosporal cultures and we detected Fusarium avenaceum.

Restricted access

Abstract

In the study, suitability of porridge, bun, and salad prepared from processed pearl millet FBC16 and sorghum PSC4 had been evaluated organoleptically by a panel of semi-trained judges and 25 non-insulin dependent diabetes mellitus subjects. Organoleptically, germinated pearl millet was found to be more suitable for porridge (50%) and salad (100%), while puffed sorghum was best suitable for bun (15%) preparation. Prepared porridge had significantly (P ≤ 0.05) higher protein (16.9%) and total phenols (178.8 mg GAE/100 g) contents and antioxidant capacity (1,036 mg TE/100 g) than control. The dietary fibre and in vitro starch digestibility of composite porridge and bun increased significantly (P ≤ 0.05). Most acceptable composition of porridge, bun, and salad had low glycaemic index (17.64–26.79) and medium to low glycaemic load (8.82–13.40). Suitability of pearl millet and sorghum using appropriate processing techniques (germination and puffing) is recommended for preparation of indigenous food products especially for diabetics.

Open access

Abstract

This study aimed to investigate the anti-obesity potential of camel colostrum and milk proteins as well as their enzymatic hydrolysates. Camel colostrum and milk proteins were treated using six proteolytic enzymes (pepsin, trypsin, α-chymotrypsin, pancreatin, papain, and pronase). The degree of hydrolysis was measured to verify the degradation of proteins. The in vitro anti-obesity activity was evaluated using the pancreatic lipase inhibitory assay. Camel colostrum and milk protein hydrolysates exhibited different degrees of hydrolysis ranging from 17.69 to 43.97%. The protein content varied between 56.08–61.95% and 37.39–41.72% for camel colostrum and milk protein hydrolysates, respectively. The hydrolysates displayed significantly higher anti-obesity activity than the undigested proteins at all tested concentrations (P < 0.05). Colostrum protein hydrolysate generated with pancreatin had the highest anti-obesity potential (59.92%). These results suggest that colostrum and milk protein hydrolysates could be used to formulate functional foods and nutraceuticals.

Open access

Abstract

In the modern era, nutraceutical properties of horticultural crops are indispensable to determine their adaptability to different agro-ecological regions. The present study exploits the potential of mulches (P: plastic mulch; S: straw mulch; N: No mulch) in relation to drip irrigation (I1: 100%, I2: 80%, I3: 60% of crop evapotranspiration (Etc)), and fertigation (F1: 100%, F2: 80%, F3: 60% of recommended dose of fertilizer (RDF): 125 kg N, 62.5 Kg P2O5, 62.5 kg K2O per ha) on Pak choi at three maturity stages in the North West region of India. Plant fresh weight was the highest at 55 days after transplanting (DAT); however, maximum soil plant analysis development (SPAD) values were registered at 45 DAT. Antioxidant activity, FRAP, DPPH, phenols, flavanols, total sugars, ascorbic acid, free amino acids, and irrigation water use efficiency were observed significantly higher in plants grown on plastic mulch at different levels of irrigation and fertigation. It is envisioned that Pak choi plants had the highest nutritional value at 45 DAT from plots mulched with silver-black, irrigated at 80% Etc, and fertigated at 100% RDF. The nutrient enriched plants are used for green salad and as ingredients for the preparation of many recipes in the semi-arid and sub-tropic areas of India.

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Acta Alimentaria
Authors:
J.J. Lin
,
Q.H. Meng
,
Z.F. Wu
,
S.Y. Pei
,
P. Tian
,
X. Huang
,
Z.Q. Qiu
,
H.J. Chang
,
C.Y. Ni
,
Y.Q. Huang
, and
Y. Li

Abstract

This paper explores the prediction of the soluble solid content (SSC) in the visible and near-infrared (400–1,000 nm) regions of Baise mango. Hyperspectral images of Baise mangoes with wavelengths of 400–1,000 nm were obtained using a hyperspectral imaging system. Multiple scatter correction (MSC) was chosen to remove the effect of noise on the accuracy of the partial least squares (PLS) regression model. On this basis, the characteristic wavelengths of mango SSC were selected using the competitive adaptive reweighted sampling (CARS), genetic algorithm (GA), uninformative variable elimination (UVE), and combined CARS + GA-SPA, CARS + UVE-SPA, and GA + UVE-SPA characteristic wavelength methods. The results show that the combined MSC-CARS + GA-SPA-PLS algorithm can reduce redundant information and improve the computational efficiency, so it is an effective method to predict the SSC of mangoes.

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Abstract

This paper provides a rapid method coupled with chemometrics to visualise PEL quality of eight regions. The contents of mineral elements, Vitamin C (Vc), and colour parameters were measured using spectrophotometric methods. The volatile substances were determined by electronic nose (E-nose) and headspace solid phase micro-extraction with gas chromatography-mass spectrometry (HS-SPME/GC-MS). Chemometric analyses were employed to visualise the sample distribution according to the geographical origin. The colour parameters, Vc, and mineral contents of PEL from diverse origins were significantly different (P < 0.05). A total of 25 volatile organic compounds (VOCs) were identified from PELs, with the highest percentage of components being ethyl acetate. The combination of HS-SPME/GC-MS and E-nose can properly characterise PEL samples. Therefore, the results of this exploratory work highlight the possibility of discriminating PEL from different regions.

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Abstract

Synthesis of nanoparticles can be long and costly processes using physical and chemical methods. Biological synthesis of nanoparticles is known to be cheaper and easier than other methods. In this study, silver nanoparticles (AgNP) were obtained by biological synthesis, also known as green synthesis, using Sorghum bicolor var. technicum (Körn) Stapf ex Holland seed extract, popularly known as sorghum. AgNPs were characterised by SEM, EDS, TEM, FT-IR, and UV-Vis Spectroscopy. SEM images confirmed that the shape of AgNPs was spherical. TEM analysis showed that the average sizes of AgNPs ranged from 51 to 56 nm. EDS analysis confirmed the presence of AgNPs by detecting a silver ion peak at 3 KeV. UV-Vis spectroscopy analyses indicated that the brown-burgundy colour of AgNPs exhibited maximum absorbance at 450 nm. The biological activities of the extract and AgNPs were investigated through antimicrobial, antibiofilm, antioxidant, mutagenic, and DNA cleavage activity analyses. The extract exhibited the highest MIC value against Gram-positive bacterium Bacillus subtilis (0.62 μg mL−1), whereas AgNPs demonstrated the highest antimicrobial activity specifically against Gram-negative bacterium Escherichia coli (0.31 μg mL−1). The antibiofilm results revealed that the extract displayed the highest percentage of biofilm inhibition against B. subtilis, while AgNPs exhibited notable efficacy against both Candida albicans yeast and Pseudomonas aeruginosa bacterium. The antioxidant activities were evaluated using DPPH and ABTS•+ methods, and it was determined that both samples had high antioxidant activity. Mutagenicity of the extract and AgNPs were evaluated by the Ames/Salmonella test using two strains of Salmonella typhimurium (TA98 and TA100). The mutagenic activity of the extract increased depending on the concentration for both strains, while AgNP did not show mutagenicity at any concentration. The agarose gel electrophoresis method showed that the extract and AgNPs cleaved DNA in the presence of an oxidising agent.

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Abstract

In this study, a water-soluble novel polysaccharide called TPS was successfully prepared and isolated from Liubao tea. The optimal extraction conditions resulted in a yield of 10.70% for the crude TPS. The purified TPS exhibited unique physicochemical properties and structural characteristics. It was identified as an acidic polysaccharide with trace binding proteins, with a →4)-α-D-Galp-(1→) residue. The purified TPS had a dense and uneven appearance, potential crystallisation characteristics, and structural stability. Importantly, it demonstrated the ability to inhibit glucose transport in Caco-2 cells by down-regulating the expression of sodium/glucose cotransporter 1 (SGLT1) and glucose transporter 2 (GLUT2), leading to a hypoglycemic effect. These findings highlight the potential of TPS from Liubao tea as a functional food or additive with hypoglycaemic properties.

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Abstract

Cultures used in dairy products make it possible to obtain standard industrial products. However, they all provide a uniform taste and aroma. Generally, non-starter lactic acid bacteria (NSLAB) isolated from raw-milk or artisanal cheeses offer varied sensory characteristics when integrated in cheese provided that biosafety criteria are met. Enterococcus faecium HZ was previously isolated from traditional Turkish cheese and determined to have strong antibacterial activity as well as no gelatinase and hemolysis activities. In this study, this strain was used as adjunct culture in white-brined cheese to improve the physicochemical, textural, and aromatic properties, as well as antimicrobial activity. Cheeses with E. faecium HZ had a higher sensory score, which could be due to the aroma-active compounds produced by this strain. The incorporation of E. faecium HZ also improved the microbial quality of cheeses and showed an inhibitory effect via a stable enterocin production on indicator microorganisms.

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Abstract

The nutritional and therapeutic benefits of plants are outstanding. Wild mustard (Sinapis arvensis L.) collected from different regions was analysed for its phenolic, flavonoid, protein, and biological activity levels. In this case, the plant ethanol extract was obtained using a soxhlet apparatus. Rel assay kits and the DPPH test were used to assess the plant's antioxidant activity. The agar dilution test was used to determine antimicrobial efficacy. A549 lung cancer cells were used in an MTT assay to measure antiproliferative activity. The Folin−Ciocalteu reagent was used to quantify the total phenolic content of the sample. The amount of flavonoids was determined using an aluminium chloride test. The amount of protein was calculated using the AOAC's standard technique. Based on the research conducted, it was shown that the maximum total antioxidant status (TAS) value for the ethanol extract of wild mustard from various places was 5.232 ± 0.047 mmol L−1. At a concentration of 2 mg mL−1, DPPH activity was measured to be 82.06 ± 1.01. The maximum levels of total phenolic, flavonoid, and protein were 80.57 ± 2.19 mg g−1, 154.07 ± 2.79 mg g−1, and 7.75 ± 0.24%, respectively. Doses of 25–100 μg mL−1 of plant extracts were effective against fungal strains, whereas doses of 50–200 μg mL−1 were beneficial against bacterial strains. The plant extracts were shown to have potent antiproliferative properties. It was found that wild mustard's phenolic, flavonoid, protein, and biological activity levels varied according to the location from which it was gathered. It was also concluded that wild mustard had significant biological activity.

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Abstract

The aim of this study was to assess the nutritional quality of homemade beef sausages by examining the amino acid, biogenic amine, and fatty acid composition. The most abundant amino acids were Ala (15.56%), Leu (13.28%), Gly (8.64%), Pro (8.41%), Ser (8.26%), and Val (7.65%). The essential amino acids accounted for 44.30% of total amino acids. Apart from the protein building amino acids, the free amino acid content was relatively high, accounting for 10% of total amino acid content. The average biogenic amine concentration in the sausage samples was low (1.69 mg kg−1). Saturated fatty acids accounted for 59.10% of total fatty acids, followed by monounsaturated (38.63%) and polyunsaturated fatty acids (2.27%). The fatty acid profile was dominated by oleic (C18:1, 34.37%) and palmitic (C16:0, 30.24%) acids, and short-chain fatty acids were also present, which may have a positive impact on gut health. The results show that beef sausages have a high nutritional value and are a good source of essential amino acids, free amino acids, and fatty acids that are important for human health.

Open access

Abstract

In this study, it is aimed to encapsulate some functional components of the olive leaves. Olive leaf extract was encapsulated using solution of sodium alginate, sodium alginate/gelatine, and sodium alginate/agar as wall material by ionic gelation technique. Also, olive leaf extract was encapsulated using solution of gelatine as wall material by cold gelation technique. The viscosities of the coating materials used in the study were investigated. An optimisation process was carried out to determine the injection time to be applied in the ionic gelation technique and the encapsulation efficiencies, particle sizes, swelling ratios, in vitro release profiles, and antioxidant activities of the obtained capsules were determined. While the encapsulation efficiency of the capsules obtained by the cold gelation technique was determined as the highest (98.2 ± 0.99%), it was revealed that the viscosity of the wall material used in the ionic gelation technique was important in the encapsulation efficiency. The particle size and swelling rate of the capsules obtained using the cold gelation technique were the highest. The release rate of oleuropein was generally higher at gastric pH than at intestinal pH. A correlation was found between antioxidant activities and the encapsulation efficiency of capsules.

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Abstract

A large amount of waste, especially the outer part of citrus fruits (peel), is generated after consuming the pulp and it remains unused. The valorisation of this waste by recovering its bioactive compounds seems interesting. The aim of this study was to find the optimal conditions using ultrasound-assisted extraction (UAE) that yield the highest carotenoid content and better antioxidant activity from Citrus reticulata Blanco peels.

Response surface methodology (RSM) through Box–Behnken experimental design was used to optimise the conditions for carotenoid extraction using UAE. Hexane concentration, temperature, and sonication time were selected as the main factors.

The results revealed that all independent variables affected the responses. The optimal UAE conditions for hexane concentration, temperature, and sonication time were 60.76%, 36.45 °C, and 37.32 min, respectively. The values of total carotenoid content (TCC) and total antioxidant activity (TAA) obtained by UAE were higher than those obtained by the maceration extraction method.

It can be concluded that the medium and extraction parameters, including hexane concentration, temperature, and sonication time, significantly influenced the recovery of carotenoids and antioxidant activity. The optimisation study allowed determining the appropriate conditions to maximise both responses. Compared to conventional maceration, the UAE method was superior and more efficient for extracting carotenoids from C. reticulata Blanco peels.

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Abstract

Food allergies became a major public health and food safety interest in the past decades as their prevalence is increasing, and their only available treatment is a strict elimination diet that necessitates appropriate food labelling regulations. While such regulations are available worldwide, most of them are not taking into account inadvertent allergen cross-contamination and they usually do not define threshold doses that could support the industry in their endeavour to provide reliable food labels for allergic consumers. This resulted in the proliferation of the “may contain” type precautionary allergen labelling (PAL), which is voluntary and is intended to warn consumers for potential unintended contamination with an otherwise undeclared allergen. As this kind of labelling is hardly ever based on actual risk assessment, it puts both the industry and the consumer into a difficult position. A promising tool towards the solution of this problem could be allergen threshold doses based on clinical data, which are becoming increasingly available. This review intends to present this process, the new ways of improved risk assessment it opens, and its implications for food analysis.

Open access

Abstract

The aim of this study was to evaluate the possibility of storage of mangoes (Mangifera indica L.) coated with chitosan-based nano-silver films. Chitosan-based nano-silver films were first made using chitosan with three degrees of deacetylation of 70, 80, and 90%. The films were then used for coating the mango fruits. All coated mangoes and the control samples were stored at 12 °C in a cooling room. The respiration rate, ethylene production rate, weight loss, firmness, total soluble solids, total acid, vitamin C, total sugar, and change of peel colour were evaluated once every 5 days during the storage period. As observed, the coating using the chitosan-based nano-silver films did not induce significant negative alterations on most of the physical characteristics and chemical constituents of the fruits. In addition, the coating using those materials helped reduce the respiration and the ethylene gas production and retard the ripening process of mango fruits. The chitosan-based films with higher deacetylation degrees (CN80 and CN90) better moderated the respiration of mangoes. The coating using chitosan-based nano-silver films prolonged the shelf-life of mangoes (up to 35 days) compared to the control (less than 10 days).

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Abstract

Background

Early identification of COVID-19 (coronavirus disease of 2019) by diagnostic tests played an important role in the isolation of infectious patients and management of this pandemic. Various methodologies and diagnostic platforms are available. The current “gold standard” for SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) diagnosis is real-time reverse transcriptase‐polymerase chain reaction (RT-PCR). To overcome the limitations posed by the short supply experienced early during the pandemic and to increase our capacity, we assessed the performance of the MassARRAY System (Agena Bioscience).

Methods

MassARRAY System (Agena Bioscience) combines RT-PCR (reverse transcription-polymerase chain reaction) with high-throughput mass spectrometry processing. We compared the MassARRAY performance to a research-use-only E-gene/EAV (Equine Arteritis Virus) assay and RNA Virus Master PCR. Discordant results were tested with a laboratory-developed assay using the Corman et al. E-gene primers and probes.

Results

186 patient specimens were analyzed using the MassARRAY SARS-CoV-2 Panel. The performance characteristics were as follows: the positive agreement was 85.71%, 95% CI (78.12 – 91.45), and the negative agreement was 96.67%, 95% CI (88.47 – 99.59). 19/186 (10.2%) results were found to be discordant and assessed by a different assay with the exception of 1, where the sample was not available for repeat testing. 14 out of 18 agreed with the MassARRAY after testing with the secondary assay. The overall performance after discordance testing was as follows: the positive agreement was 97.3%, 95% CI (90.58 – 99.67), and the negative agreement was 97.14%, 95% CI (91.88 – 99.41).

Conclusion

Our study demonstrates that the MassARRAY System is an accurate and sensitive method for SARS-CoV-2 detection. Following the discordant agreement with an alternate RT-PCR test, the performance was found to have sensitivity, specificity, and accuracy exceeding 97%, making it a viable diagnostic tool. It can be used as an alternative method during periods when real-time RT-PCR reagent supply chains are disrupted.

Open access

Abstract

The aim of this study was to isolate lactic acid bacteria (LAB) from artisanal cheeses and evaluate their probiotic potential and antibiotic susceptibility under in vitro conditions. Cheeses obtained at different maturation times were analysed for moisture and lipid contents, as well as for the presence of various microorganisms, including coagulase positive staphylococci, Salmonella spp., Escherichia coli, Listeria monocytogenes, filamentous fungi, yeasts, total mesophilic bacteria, and LAB. After identification, the selected LAB were subjected to human gastrointestinal tract (HGT) conditions to evaluate their survival rates. Of the 18 Lactobacillus strains isolated, 11 survived the HGT test and presented γ-haemolysis. No resistance was observed against antibiotics. Lactobacillus fermentum C1a, C1b, C1c, and C1f, as well as Lactobacillus paracasei C1d, C1e, and C1g, were identified as potential starter cultures for the food industry.

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Abstract

Obesity and other unhealthy behaviors are behind cardiovascular morbidity and mortality, with the Roma population particularly at risk. The aim of our cross-sectional (questionnaire- and physical measurements-based) study was to compare the prevalence of obesity in Hungarian, Romanian, and Slovakian Hungarian-speaking Roma and non-Roma (N = 1893) in relation to lifestyle-related risk factors for cardiovascular diseases (CVD). In the total sample, the proportion of extreme obesity was higher in Roma (P < 0.001) than non-Roma. The mean waist circumference was the highest in Hungary (P < 0.001). Visceral fat was higher in the Hungarian Roma sample than in the Slovak (P = 0.006) or Romanian Roma samples (P = 0.005). Hungarian Roma total cholesterol levels were lower than in the Slovak (P < 0.001) or Romanian samples (P < 0.001). Hypertension and cholesterol levels were associated with a higher risk among non-Roma men (P < 0.001), and the presence of smoking increased CVD risk among both men (P = 0.024) and women (P < 0.001) in the Roma minority. The combined presence of several risk factors was found mainly in Roma. Overall, Roma scores were found to be worse, but ethnicity did not provide clear evidence for the questions examined, but rather the level of education, which is associated with socioeconomic status.

Open access

Abstract

Radio frequency (RF) heating of agri-food, especially low moisture viscous sauces (LMVS), have obvious advantages. However, uneven heating is one main problem of RF heating technology that has to be solved. Due to the unclear heating mechanism and the difficulty to measure the three-dimensional temperature distribution in the heated object, computer-aided analysis method was adopted. Based on the RF heating numerical calculation model after experimental verification and the characteristics of polyetherimide (PEI) assisted RF heating of peanut butter (PB), this study proposed an improved method for an existing protocol. Meanwhile, parameters of the new protocol were optimised by the Multi-objective Global Optimisation (MGO) of its surrogate model. Results demonstrated that the best size of PEI block in the new protocol was Φ100 × 9.5 mm and the positional height was 12 mm. When the pasteurisation temperature Tp was set to 70 °C and the control temperature Tc was set to 75 °C, the temperature uniformity evaluation indices, Over-shoot Temperature Control Index (OTCI) and Targeted Penetration Depth (TPD), were 0.920% and 3.975 mm, respectively. Compared with 4.845% and 4.940 mm before improvement, the new protocol achieved significant optimisation and improved the temperature uniformity effectively. This also proved the feasibility of MGO method of surrogate model in relevant studies.

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Abstract

In the present study, six different edible coatings were evaluated to assess their microbicidal efficiency on pre-treated disinfected fresh cut guava. Among all coatings viz. alginate, pectin, carboxy methylcellulose, carrageenan, and starch, chitosan showed significant microbial growth inhibition and preservation of physico-chemical characteristics of fresh cut guava. Further, optimisation of coating parameters i.e. concentration (% w/v) and dipping time (min) was performed using Response Surface Methodology. It revealed that the fresh-cut guava dipped in 1% (w/v) chitosan for 3 min had desirability level of 91% and extension of its shelf life up to 9 days, as compared to 5 days shelf life of uncoated fresh-cut guava, maintaining all its physico-chemical parameters and microbial growth under the permissible level. Validation of optimised conditions was conducted at 5.0 kg scale that resulted in firmness of 1.90 (kg), 2.6 g/100 g sugars content, 8.0 °Brix total soluble solids content, 3.4 pH, 4.1 log CFU g−1 total plate count, 3.1 log CFU g−1 yeast and moulds count, and 3.1 log CFU g−1 total coliforms count on fresh-cut guava at 9th day of refrigeration storage. Shelf life analysis revealed that chitosan coated fresh cut guava can stay fresh till 10th day under refrigeration with maintaining all its nutritive, microbiological, and sensory properties in the acceptable range.

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Abstract

SARS-CoV-2 infection still poses health threats especially to older and immunocompromised individuals. New emerging variants of SARS-CoV-2, including Omicron and Arcturus, have been challenging the effectiveness of humoral immunity resulting from repeated vaccination and infection. With recent study implying a wave of new mutants in vaccinated people making them more susceptible to the newest variants and fueling a rapid viral evolution, there is a need for alternative or adjunct approaches against coronavirus infections other than vaccines. Our earlier work indicated that a specific combination of micronutrients and phytochemicals can inhibit key infection mechanisms shared by SARS-CoV-2 and its variants in vitro. Here we demonstrate in vivo that an intake of this micronutrient combination before and during infection of mice with engineered SARS-CoV-2 virions and HCoV-229E virus results in a significant decrease in viral load and level of spike protein in the lungs. This was accompanied by decreased inflammatory response, including TNFα, IL1β, ILα, and IL17. These and our earlier results confirm that by targeting multiple mechanisms simultaneously by a combination treatment we can effectively and safely challenge SARS-CoV-2 and HCoV-229E virus. If clinically confirmed, such an approach could complement already in-use preventive and therapeutic strategies against coronavirus infections.

Open access
Acta Alimentaria
Authors:
S. Labidi
,
A. Jánosity
,
A. Yakdhane
,
E. Yakdhane
,
B. Surányi
,
Cs. Mohácsi-Farkas
, and
G. Kiskó

Abstract

Listeria monocytogenes is able to form biofilms on food contact surfaces. Effectiveness of salt concentration, pH, and temperature on the formation of L. monocytogenes biofilms was evaluated individually and in combinations using microtiter plate assay by measuring the optical density. The tested strains differed in their biofilm formation (low, moderate, and strong) ability. At 37 °C, decreasing amounts of biofilms was observed in almost all L. monocytogenes strains when the NaCl concentration increased from 0.05 to 15%, but all strains were able to form biofilm even at 1 °C. There was no significant difference in biofilm formation between pH 4, 5, and 6, except for some strains. When stress conditions were tested in combination, the addition of 15% NaCl significantly inhibited the growth of L. monocytogenes at 1 °C and 4 °C, and the weak biofilm-forming strains were less sensitive to the temperature and to NaCl treatments than the strong biofilm-forming strains. These results enhance our knowledge of the application of NaCl, temperature, and pH stresses in the food industry and provide basis to develop new strategies for control of biofilm formation of this pathogen.

Open access