Browse

You are looking at 1 - 10 of 8,212 items for :

  • Biology and Life Sciences x
  • Refine by Access: All Content x
Clear All

Abstract

Elderberry pomace, a by-product generated by elderberry processing industries, may be a favourable resource for further utilisation due to its components of high nutritional quality. In our research, elderberry pomace extract (EP) was added to apple juice as natural food additive for controlling microbial spoilage and enriching antioxidant components.

During the 8-week storage period of enriched apple juice (EPA) and control apple juice samples antioxidant properties were evaluated using the FRAP assay, Folin–Ciocalteu method, and pH differentiation method. The amount of polyphenols components was quantified using an RP-HPLC method. The microbiological status of samples was studied by determining the total viable and yeast/mould counts. The EPA is an important source of polyphenol components and other bioactive compounds, and the results suggest that extract of elderberry pomace could be a promising natural preservative to improve microbiological stability during refrigerated storage and increase the quality of apple juice.

Open access
Acta Alimentaria
Authors:
Z.Z. Yang
,
J.Q. Zhang
,
B.B. Shi
,
J.Q. Qian
, and
H. Guo

Abstract

Myricetin has been reported to have a wide variety of beneficial physiological functions. The present study investigated the antihyperlipidaemic activity of myricetin against hyperlipidaemia of high-fat diet-fed obese rats. The four-week antihyperlipidaemic activity was assayed by giving different doses of myricetin to hyperlipidaemic rats. Results showed that myricetin could reduce the harm caused by oxidative stress, decrease thiobarbituric acid reactive substances value, and decrease total cholesterol and triacylglycerol levels of hyperlipidaemic rats. Quantitative analysis of gene expression showed that myricetin's lipid-lowering activity can be activated by downregulating gene expression of fatty acid synthase (FAS) and peroxisome proliferator-activated receptor-γ (PPARγ) with upregulation of hormone-sensitive lipase (HSL) mRNA level. Thus, myricetin had significant health benefits and could be explored as a potentially promising dietary supplement for treating hyperlipidaemia.

Open access

Abstract

Botrytis cinerea is one of the fungal pathogens with the widest host plant spectrum, causing serious yield losses and significant economic damage in vineyards from year to year. As an ubiquitous, polyphagous fungal pathogen, with both saprophytic and parasitic lifestyle. The sequential use of active substances belonging to the same chemical family to protect vineyards can lead to an increase in fungal chemical resistance, which is reflected in the enrichment of point mutations in the genomic regions coding proteins involved in the mechanism of action of different pesticides. The aim of our studies was to compare the sensitivity to different fungicides of B. cinerea populations in two wine regions with different pest management practices: the Tokaj region, where the presence of B. cinerea is necessary to produce noble rot wines, and the adjacent Eger Region, where a total protection against B. cinerea is desired. Our study is the first Hungarian report of some previously studied resistance mutations in ERG27 and SDHB protein-coding genes. We identified point mutations in ERG27 transmembrane domain that have not been previously described but may affect the emergence of resistance to certain fungicides. Our study shows that the B. cinerea population of the Northern Hungary region is consistently characterized by an increase in fenhexamid resistance.

Open access

Abstract

Conversion of economic microcrystalline cellulose (MCC) into high value-added prebiotic glucans, is not only stimulates utilisation of renewable lignocellulosic biomass, but also provides cheap prebiotics to reduce high incidence of obesity and metabolic syndrome. Herein, glucans (C0.25–C0.50–C1.00) from MCC were prepared by pre-impregnation with dilute sulphuric acid (0.25–0.50–1.00%) and ball-milling treatment for 1 h. NMR spectroscopy and gel-permeation chromatography of the glucan products showed a significant reduction in the degree of polymerisation (DP) and molecular weights (Mw). All prepared glucans improved gut stress evaluated by in vitro digestion and fermentation (young and aging mouse faecal inocula). C1.00 with lower DP and Mw showed better water solubility, earlier peak, and exhibited increased 1-diphenyl-2-picrylhydrazyl activity, higher ratios of Lactobacillus to Escherichia coli, and a higher level of short chain fatty acids better than C0.25 and C0.50 treatment (P < 0.05). Better prebiotic effects were observed in aging mice than in young mice. The highest ratio of Lactobacillus to E. coli was a 2.13-fold increase for aging mice compared to a 1.79-fold increase for young mice, relative to the initial value after C1.00 treatment. The study provides a novel pathway and a new resource for producing glucan.

Restricted access

Abstract

Mango fruits' quality, marketability, and shelf life are significantly influenced by postharvest decay. Mango fruit disease development during storage is inhibited by fungicides. The objective of this investigation was to assess the relative effectiveness of two fungicides, azoxystrobin 18.2% + difenoconazole 11.4% SC and hexaconazole 5% SC, in mitigating postharvest deterioration of mango cv. ‘Langra’ during low temperature storage. Three pathogens were found associated with postharvest decay of mango, i.e. Colletotrichum gloeosporioides, Alternaria alternata, and Penicillium expansum. In comparison to untreated ones, the preharvest application of fungicide treatments provided noticeably better disease control. The foliar application of azoxystrobin 18.2% + difenoconazole 11.4% SC (0.1%) 15 days before the harvesting of fruits significantly improved fruit firmness, soluble solid content, titratable acidity, reduced the disease incidence, percentage disease index, and lesion diameter followed by the application of hexaconazole 5% SC (0.1%) compared to the control. Furthermore, it was found that pre-harvest fungicide spraying of azoxystrobin 18.2% + difenoconazole 11.4% SC (0.1%) was an effective treatment for lowering postharvest deterioration and enhancing the physio-chemical characteristics of mango fruits during low-temperature storage.

Restricted access

Abstract

Ergosterol, as a precursor for synthesising useful molecules like vitamin D2, possesses significant physiological functions in both fungal and human systems. In fungi, ergosterol plays a crucial role in stress responses. In contrast to Saccharomyces cerevisiae yeast, the changes in specific ergosterol content of Kluyveromyces marxianus under various stress conditions are less known. This study investigated how ergosterol content changes in response to different stress factors. Carbon to nitrogen (C/N) ratio was examined using experimental design. The effects of aeration and shear force beside constant overall volumetric mass transfer coefficient (KLa) were examined. Cell growth and specific ergosterol content were investigated using ethanol stress during a two-stage fermentation. Based on the results, contradictory settings regarding C/N ratio and shear force were found to be favourable for cell growth and specific ergosterol content. However, increased aeration consistently elevated specific ergosterol content and favoured cell growth as well (2.5-fold and 1.5-fold, respectively). In K. marxianus fermentations, higher ergosterol yield can be achieved through a two-stage fermentation (138.9 mg L−1 compared to 52.9 mg L−1), where the first stage provides favourable conditions for cell growth, and the second stage involves stress (beneficial for ergosterol production) conditions. Conclusions drawn from the two-stage fermentation results suggest that early transitioning of cell growth to the second phase will not result higher adaption and specific ergosterol content compared to the transition at the end of exponential growth phase.

Open access
Acta Alimentaria
Authors:
F. Brahmi
,
S. Achat
,
I. Mateos-Aparicio
,
T. Sahki
,
O. Bedjou
,
N. Ben Bara
,
L. Benazzouz-Smail
,
H. Haddadi-Guemghar
,
K. Madani
, and
L. Boulekbache-Makhlouf

Abstract

This work proposes the optimisation of the ultrasound assisted extraction (UAE) for total phenolic content (TPC) from potato peels (PP). The optimised extract was obtained using ethanol 20% (v/v) for 30 min at 40 °C, and it was found to be rich in total phenolics (45.03 ± 4.16 mg GAE/g DM) and flavonoids (7.52 EQ/g DM) and exerted a good antioxidant effect with IC50s of 125.42 ± 2.78, 87.21 ± 7.72, and 200.77 ± 13.38 μg mL−1 for DPPH, phosphomolybdate, and FRAP, respectively. PP were used for the fresh cheese formulation, and this supplementation did not impact its physicochemical properties; however, the phenol content and antioxidant capacity of formulated cheeses were improved. PP-enriched fresh cheese presented a good acceptability, even better than the control.

Restricted access

Abstract

Serious risks to human health are posed by acute campylobacteriosis, an enteritis syndrome caused by oral infection with the food-borne bacterial enteropathogen Campylobacter jejuni. Since the risk for developing post-infectious autoimmune complications is intertwined with the severity of enteritis, the search of disease-mitigating compounds is highly demanded. Given that benzoic acid is an organic acid with well-studied health-promoting including anti-inflammatory effects we tested in our present study whether the compound might be a therapeutic option to alleviate acute murine campylobacteriosis. Therefore, microbiota-depleted IL-10−/− mice were perorally infected with C. jejuni and received benzoic acid through the drinking water from day 2 until day 6 post-infection. The results revealed that benzoic acid treatment did not affect C. jejuni colonization in the gastrointestinal tract, but alleviated clinical signs of acute campylobacteriosis, particularly diarrheal and wasting symptoms. In addition, benzoic acid mitigated apoptotic cell responses in the colonic epithelia and led to reduced pro-inflammatory immune reactions in intestinal, extra-intestinal, and systemic compartments tested on day 6 post-infection. Hence, our preclinical placebo-controlled intervention trial revealed that benzoic acid constitutes a promising therapeutic option for treating acute campylobacteriosis in an antibiotic-independent fashion and in consequence, also for reducing the risk of post-infectious autoimmune diseases.

Open access