Browse

You are looking at 31 - 40 of 2,413 items for :

  • Materials and Applied Sciences x
  • 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

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
Acta Alimentaria
Authors:
M. Reyzov
,
M. Eftimov
,
S. Gancheva
,
M. Todorova
,
M. Zhelyazkova-Savova
,
M. Tzaneva
, and
S. Valcheva-Kuzmanova

Abstract

This study evaluated the effects of Aronia melanocarpa fruit juice (AMFJ) on the liver in a model of high-fat, high-fructose (HFHF) diet-induced metabolic syndrome (MS). Fifty rats were allocated to five groups – Control, MS, MS+AMFJ2.5, MS+AMFJ5, and MS+AMFJ10. The control group was fed a standard diet, while the other groups were provided a HFHF diet. During MS induction, daily oral treatment was performed. Control and MS groups received 10.0 mL kg−1 distilled water, while the other three groups received AMFJ at doses of 2.5, 5.0, and 10.0 mL kg−1, respectively. After 10 weeks, liver samples were collected and inspected histologically as well as immunohistochemically to determine the expression of Bax, Bcl-2, and MAC387. Bax/Bcl-2 ratio was calculated. In MS rats, steatotic, inflammatory and degenerative alterations of the liver were detected, Bax and MAC387 were markedly elevated, while Bcl-2 was non-significantly reduced. The Bax/Bcl-2 ratio significantly increased. The histopathological alterations were prevented by the AMFJ treatment. Compared to MS group, Bax and MAC387 values were significantly lower and Bcl-2 value was higher resulting in significantly lower (P < 0.001) Bax/Bcl-2 ratio in all AMFJ-treated groups. AMFJ, administered during MS induction in rats, prevented the occurrence of inflammatory, steatotic, degenerative, and pro-apoptotic changes in the liver.

Restricted access

Abstract

The article evaluates how well the goals of the European Green Deal are justified, especially considering the risks to energy and food security arising from the conflict between Russia and Ukraine. We agree with the objectives of the European Green Agreement as a whole, but whether some of the objectives which feature in the EASAC study can be achieved by 2030 is questionable, and the description of the tools necessary to achieve the objectives is incomplete. Among other things, there is hardly any mention of the role played by precision farming with digitalization, which is a revolutionary change from an ecological and economic point of view, in reducing the use of synthetic inputs, in regenerating the original state of the soil, in reducing GHG emissions, thus in increasing biodiversity, and at the same time in intensifying production, and finally in expanding the application of biotechnology. We examine these areas in our analysis. Some of the objectives of the EASAC study to be achieved by 2030 are subject to debate, and the description of the information and communication conditions necessary to achieve the objectives is incomplete. The IoT (Internet of Things) responds to global and local challenges: it integrates the precision technologies, WSNs (Wireless Sensor Networks), artificial intelligence, mobile field (Smart Small Robots) and remote data loggers (UAVs: Unmanned Air Vehicles and satellites), Big Data, and cloud computing. Consequently, decision support is increasingly developing into unmanned decision making. IoT (Internet of Things) is the basis of “Farm to Fork” and “Lab to Field” monitoring approaches.

This article evaluates the implementation of European Green Agreement objectives in light of energy and food security risks arising from the Russia-Ukraine conflict. While overall support for the agreement exists, the feasibility of certain EASAC study objectives by 2030 is called into question due to insufficient tools specifications. Notably absent is the emphasis on precision farming with digitalization, which is a transformative ecological and economic practice. Our analyses look into its function in reducing synthetic inputs, soil regeneration, GHG emission reduction, biodiversity enhancement, production intensification, and biotechnology development. Debates surround EASAC study objectives for 2030, despite limited information and communication restrictions. The Internet of Things (IoT) arises as a solution, combining precision technology, WSNs (wireless sensor networks), AI (artificial intelligence), smart small robots, UAVs (unmanned aerial vehicles), satellites, big data, and cloud computing. As a result, decision support turns toward unmanned decision-making, with IoT laying the groundwork for “Farm to Fork” and “Lab to Field” monitoring systems.

Open access

The use of organic fertilization is declining in Hungary due to the sharp fall of livestock stand since the middle of the 1980s. Most farmers are forced to use solely chemical crop enhancers. A bifactorial small plot experiment was carried out between 10 May 2023 and 19 October 2023 in Keszthely, in order to examine the effects of farmyard manure (M), green manure (GM) and stem residues (SR) on the nutrient uptake and nitrogen utilization efficiencies of maize at equidistantly increasing (0–70–140–210–280 kg N ha–1) nitrogen doses. The relationship between some vegetative traits (dry biomass weight, Leaf Area Index (LAI)) and yield, furthermore leaf relative water content (RWC) was also examined. According to the results, organic fertilizer substitution significantly increased the N content both in whole plant and grain samples of NPK+M and NPK+GM+SR treatments, compared to the chemically fertilized control (NPK). In case of P and K only slight differences were observed. Whole plant K contents of NPK+M were significantly higher than in the other treatments (P = 0.045; P = 0,005), furthermore P contents in grain samples were significantly higher in NPK+M (P = 0.004) and NPK+GM+SR (P = 0.05) than in control. Harvest index (HI [%]) of NPK+M and NPK+GM+SR were 1.06 and 1.05 times higher than in NPK. Depending on the treatment, P0023 maize hybrid absorbed 58.7–74.64% of total N uptake in the grain (HIN%), and the utilization of 1 kg N fertilizer for the extra yield above the yield of the individual control was 0.39–1.38 kg (AREN). Significant positive correlations were observed between dry biomass weight and yield (NPK: r = 0.937, P = 0.019; NPK+M: r = 0.971, P = 0.006; NPK+GM+SR: r = 0.88, P = 0.049), furthermore LAI and yield (NPK: r = 0.9, P = 0.037; NPK+M: r = 0.983, P = 0.003; NPK+GM+SR: r = 0.784, P = 0.117). Highest RWC values – which may be related to better soil aggregate stability – were measured in NPK+GM+SR treatment, therefore there may be a great potential in this treatment among drought conditions. The effect of organic amendments is particularly noticeable with smaller nitrogen doses so they should be used to reduce inorganic fertilizer application and the resulting environmental risks.

Open access

Abstract

Steviol glycosides (SGs) are natural sweeteners derived from stevia leaves, which have various applications in food and beverage products. The extraction efficiency of SGs depends on several factors, such as solvent type, solid to solvent ratio, centrifugal force, and temperature. This study aimed to compare the effects of different solvents (ethanol and water) and leaf moisture (dry and fresh) on the extraction efficiency of major steviol glycosides (SGs) of rebaudioside A (Reb A), stevioside (ST), and rebaudioside C (Reb C) in stevia (var. Levent 93) plant. A Box–Behnken design was used to optimise the extraction parameters for each extraction type. The results showed that ethanol was a more effective solvent than water, however, aqueous extraction was more environmentally friendly and low-cost, and could also yield high concentrations of SGs when fresh leaves were used. The major SGs had similar concentrations in ethanolic extraction, but Reb A was twice as high as ST in aqueous extraction. Reb C was influenced by the solid to solvent ratio in both extraction types, but more so in water extraction. Temperature had a positive effect on ST and Reb C in water extraction of fresh leaves, but not in water extraction of dry leaves or ethanolic extraction. The results of this study contribute to the optimisation of SGs extraction from stevia leaves and provide insights for future research on the effects of different solvents and extraction parameters on the quality and purity of SGs.

Restricted access