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Progress in Agricultural Engineering Sciences
Authors: N. Anter, M. Y. Guida, M. Kasbaji, A. Chennani, A. Medaghri-Alaoui, E. M. Rakib, and A. Hannioui

Abstract

In this scientific paper, thermochemical conversion of redwood (RW) was studied. Using the thermogravimetric analysis' technique (TGA), the thermal behavior of RW samples was examined at four heating rates ranging from 5 to 20 K min−1 in inert atmosphere between 300 and 900 K. Two main objectives have been set for this study; the first one was the determination of the kinetic decomposition parameters of RW (Pinus sylvestris L.), and the second one was the study of the variation of characteristic parameters from the TG-DTG curves of the main RW's components, such as; cellulose, hemicellulose and lignin. The kinetic analysis was performed using three isoconversional methods (Vyazovkin (VYA), Friedman (FR) and Flynn-Wall-Ozawa (FWO)), Avrami theory method and the Integral master-plots (Z(x)/Z(0.5)) method to estimate activation energy (E a), reaction order (n), pre-exponential factor (A) and model kinetic (f(x)) for the thermal decomposition of cellulose, hemicellulose and lignin components.

The DTG and TG curves showed that three stages identify the thermal decomposition of RW, the first stage corresponds to the decomposition of hemicellulose and the second stage corresponds to the cellulose, while the third stage corresponds to the lignin's decomposition. For the range of conversion degree (x) investigated (0.1 ≤ x ≤ 0.7), the mean values of apparent activation energies for RW biomass were 127.60–130.65 KJ mol−1, 173.74–176.48 KJ mol−1 and 197.21–200.36 KJ mol−1 for hemicellulose, cellulose and lignin, respectively. Through varied temperatures from 550 to 600 K for hemicellulose, from 600 to 650 K for cellulose and from 750 to 800 K for lignin, the corresponding mean values of reaction order (n) were 0.200 for hemicellulose, 0.209 for cellulose and 0.047 for lignin. The pre-exponential factor's average values for three components of RW ranges from 0.08 × 1012 s−1 to 2.5 × 1012 s−1 (A hemicellulose = 1.09 × 1012 s−1), 0.10 × 1014 s−1 to 0.28 × 1014 s−1 (A cellulose = 0.17 × 1014 s−1) and 3.07 × 1016 s−1 to 3.69 × 1016 s−1 (A lignin = 3.33 × 1016 s−1), respectively. The experimental data of RW had overlapped the D 4, D 2 and F 3 in the conversion degree of 10–30%, 30–55% and 55–70% for the three components, respectively.

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Abstract

This study was designed to investigate the effects of green tea on lipid profile, liver tissue damage, and oxidative stress in rats fed a diet including high fructose. Sprague-Dawley rats were randomly divided into four groups: Control (C), Fructose (F), Green Tea (GT), and F+GT. F and F+GT groups were given 20% fructose in the drinking water for eight weeks. Green tea (2 mg kg−1) was administrated to GT and F+GT groups by oral gavage for eight weeks. Biochemical parameters in serum and oxidative stress markers in the liver were analysed. The liver sections were stained with haematoxylin-eosin. As of the 3rd week of the experiment, the body weight of rats in the F group showed a statistically significant increase in comparison with the F+GT group. The serum glucose and triglyceride levels of the F+GT group significantly decreased when compared with the F group. The fructose-induced degenerative changes in the liver were reduced with green tea. Green tea may serve a protective role against hyperlipidaemia and liver injury in rats fed a high fructose diet.

Open access

Abstract

Indigenous yeast strains Kluyveromyces marxianus (MH6), K. marxianus (CH1), and Saccharomyces cerevisiae (C1) were screened for whey beverage production. K. marxianus (MH6) showed significantly higher (P < 0.05) fermentation efficiency (15.2%) as compare to other yeast strains. The conditions optimised for whey fermentation were 16 Brix, pH 5.5, 28 °C, and 72 h without agitation. For fermented whey beverage production, fruits viz., kinnow (Daizy), guava (Allahabad safeda), and mango (Safeda) were blended with whey at different ratios viz., 80:20, 70:30, 60:40, and 50:50. All ratios showed significant differences for biochemical and sensory analysis (P < 0.05), out of which ratios 60:40, 70:30, and 60:40 for whey kinnow, whey mango, and whey guava, respectively, were selected. To enhance the flavour of whey beverage, flavouring agents (cinnamon, cardamom, fennel seeds, and apple essence) were added. A panel of judges assessed all whey beverages on a hedonic scale basis, and cardamom whey guava beverage received the highest score of 8.16. The whey beverages were stored under refrigerated conditions after pasteurisation, and the shelf life was assessed to be 15 days. This study conferred that K. marxianus held the potential for fermented whey fruit blend beverages production and these beverages could be an alternative healthy refreshing substitute for synthetic bottled fruit beverages.

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Acta Alimentaria
Authors: B. Raposa, E. Antal, J. Macharia, M. Pintér, N. Rozmann, D. Pusztai, M. Sugár, and D. Bánáti

Abstract

Several misconceptions exist about foods and nutrition. Many believe, that the human body can “acidify”, thus, an “alkaline diet” should be followed. The acid-base balance is a characteristic of a normally functioning human body. Throughout our metabolic processes, acids and substances with acidic pH are produced continuously, which, in the case of a healthy person, does not affect the pH of the human body. In those rare cases, when an overall pH imbalance evolves in the human body due to its life-threatening nature, it requires urgent medical intervention. Furthermore, it cannot be influenced by dietary interventions.

This paper highlights evidence regarding acidification and the acid-base balance, with special attention to certain food groups. Foodstuffs have different specific pH value (acid-base character), they can be acidic, alkaline, or neutral in elemental state. Beside their chemical nature, the effect they have on the human body depends on the mechanism of their metabolism, as well. Diet and ingredients have direct and indirect effects on the human body's intracellular and extracellular compartments (especially blood and urine), still they do not influence its pH significantly.

Alkaline diets were born in the absence of evidence-based information and/or the misunderstanding and wrong interpretation of the available and up-to-date scientific facts. The convictions of consumers and the promotion of the alkaline diet lack the scientific basis, so it can be harmful or even dangerous in the long run.

In summary, scientific evidence on the efficacy or prophylactic effects of an alkaline diet is not available.

Open access

Abstract

Naturally-occurring compounds are acknowledged for their broad antiviral efficacy. Little is however known about their mutual cooperation. Here, we evaluated in vitro efficacy of the defined mixture of agents against the RdRp complex of the original SARS-CoV-2 and Omicron variant. This composition of vitamin C, N-acetylcysteine, resveratrol, theaflavin, curcumin, quercetin, naringenin, baicalin, and broccoli extract showed to inhibit activity of RdRp/nsp7/nsp8 both these variants. In vitro exposure of recombinant RdRp complex to individual compounds of this composition pointed to quercetin as the driving inhibitory compound. The outcome of this study supports the motion of antiviral efficacy of natural compounds against SARS-CoV-2 and Omicron and implies that their reciprocal or mutual interaction may augment antiviral action through simultaneous effect on different mechanisms. Consequently, this makes it more difficult for an infectious agent to evade all these mechanisms at the same time. Considering the urgency in finding effective prevention, but also side-effects free treatment of COVID-19 our results call for clinical affirmation of the benefits of this micronutrient combination in both preventive and therapeutic aspects. Whether observed effects can be achieved, by concentrations of the active agents used in these in vitro experiments, in in vivo or clinical setting warrants further study.

Open access

Abstract

To overcome the problems of seasonality and geographical location in fruit production and processing, the production of aseptic semi-finished juice is an excellent solution. Even without refrigeration, aseptic pressing has a shelf life of more than a year, making it possible to produce finished products all year round. The production technology involves the addition of ascorbic acid to the pulp to fix or preserve colour. There is an increasing customer demand for ascorbic acid substitutes on the international market. In Hungary, one of the most important exports is aseptic sour cherry juice. In our work, ascorbic acid used for colour fixation was replaced by acerola concentrate. The anthocyanin content and colour coordinate values (L*, a*, b*, H, C) of aseptically filled sour cherry juice were determined and compared with the control sample during the 12 months of storage.

Open access

As a means of assisting the selection of promising soil classification systems, a set of criteria were presented and tested. Inside the studied slightly saline plot World Reference Base (WRB) and Hungarian soil classification (HU) were compared at all four levels in terms of class separability, correlation to biomass, parsimony and homogeneity of classes. WRB surpassed HU in terms of the very important homogeneity of classes only, but HU performed better in terms of class separability, correlation to biomass and parsimony of classes. With many possible classification units WRB categorized the soil into a large number of classes, but 67% and 78% of them were single-profile classes at levels 3 and 4, respectively inside the ca 0.9 km2 area.

Open access

Szarvasmarhatartó telepen alkalmazott ivarzásindukáló hormonok megjelenése a hígtrágyában

Appearance of on-farm bovine reproductive hormones in the resulting slurry

Agrokémia és Talajtan
Authors: Eduárd Gubó, Tibor Molnár, Pál Szakál, Dóra Pordán-Háber, Ákos Bede-Fazekas, and Judit Plutzer

A review of the international literature also found that the amount and the presence in slurry of oestrus inducer hormone preparations used in intensive dairy cattle production has not been investigated. In our study, we followed the path of 5 different sex-inducing drugs (alfaglandin, PGF, dinolytic, gonavet, ovarelin) including three active pharmaceutical ingredients (D-Phe6-Gonadorelin, Kloprostenol and Dinoprost-tromethamine) used in a cattle farm in Pest County from their use until their appearance in the slurry from 2017 to 2020. The study included a review of drug consumption and a seasonal analysis of the hormonal effects of slurry produced on the farm in quarterly cycles each year. We also tested separately the hormonal effects of the hormone preparations used on the farm. For the estrogenic effect tests, the yeast test with the human estrogenic receptor was used according to ISO 19040. Statistical evaluation of the results (Pearson correlation and Principal Component Analysis) was used to identify relationships between the use of sex inducers, the reproductive biology of the colony and the estrogenic effect of the slurry. We found that the estrogenic effects of slurry and sludge are strongly correlated. All three pharmaceuticals tested showed a strong correlation with the estrogenic effect of slurry/sludge. Our investigations confirm that slurry among other reasons due to its hormone and drug content shall be considered as a material that needs to be disposed of by new treatment methods before application to the field, because of its environmental and health risks.

Open access

Abstract

Black plum sawfly (Hoplocampa minuta) is an important pest species of plum (Prunus domestica). In organic plum orchards, the yield loss caused by H. minuta larval damage can reach almost 100% occasionally. Adults feed on pollen and nectar of the plum flower; therefore, we hypothesize that, besides visual cues, also olfaction plays an important role in habitat and host finding. To understand the chemical communication mediated by flower volatiles to black sawflies, we investigated the chemical signals released from plum flowers, which can trigger the peripheral physiological responses of adult sawflies. First, using gas chromatography coupled with electroantennography (GC-EAD), we selected 18 physiologically active compounds from the headspace volatile collection of plum flowers, which triggered the H. minuta male and female antennae. Subsequently, we determine the volatilome of plum flower and identified those compounds, which elicited physiological responses, using gas chromatography coupled with mass spectrometry (GC-MS). These antennally active components in flower volatiles could be candidates for potential kairomone, which could later be used for attracting males and females of H. minuta and could contribute to developing pesticide-free, effective monitoring and lure and kill strategy against this pest.

Open access

Abstract

Consumption of infected plant tissues by decomposing organisms is an important part of ecosystem services. We tested how the common woodlouse (Porcellionides pruinosus, Isopoda: Oniscidea) may contribute to the decomposition process in a laboratory experiment in which Mycosphaerella pyri-infected pear leaves with or without the aecia of Gymnosporangium sabinae were offered as food. We recorded the loss of healthy and infected leaf tissues. Isopod survival rate was also monitored. We found (1) a certain pattern of preference in the consumption of infected leaf material; and (2) that the presence of G. sabinae reduced leaf consumption but had no effect on the ingestion of Mycosphaerella-infected spots; and (3) the mortality of P. pruinosus was adversely influenced by G. sabinae, but the results were highly dependent on confinement conditions. Our results suggest that woodlice consume plant pathogenic fungi, and therefore offer the ecosystem service of neutralizing infective plant remnants during decomposition.

Open access