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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:

Biology and Life Sciences

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Abstract

Metabolic syndrome (MS) is a serious health condition. The purpose of this study was to investigate the effects of polyphenol-rich Aronia melanocarpa fruit juice (AMFJ) on glucose tolerance, triglyceride levels, and adipose tissue in rats with MS induced by high-fat high-fructose (HFHF) diet. Fifty rats were allocated in 5 groups: control, MS, MS+AMFJ2.5, MS+AMFJ5, and MS+AMFJ10. In the course of 10 weeks, the control group was on a regular rat diet while the other groups received HFHF diet. During the experiment, control and MS groups were treated daily orally with distilled water (10.0 mL kg−1) and the other three groups – with AMFJ at doses of 2.5, 5.0, and 10.0 mL kg−1, respectively. In MS rats, glucose intolerance, hypertriglyceridemia, visceral obesity, and increased adipocyte size were observed. In AMFJ-treated groups, the serum glucose and triglycerides, as well as visceral fat and adipocyte size decreased significantly and did not differ from those of the control group. AMFJ at doses 2.5 and 5.0 mL kg−1 showed an anti-apoptotic activity in adipocytes, while at the dose of 10 mL kg−1 a pro-apoptotic effect was detected. In conclusion, AMFJ could antagonise most of the negative consequences of HFHF diet on carbohydrate and lipid metabolism in a rat MS model.

Open access

Abstract

‘Patharnakh’ (Pyrus pyrifolia Burm.) (PN), a hard pear and ‘Punjab Beauty’ (Pyrus communis L. × Pyrus pyrifolia Burm.) (PB), a soft pear are dominant low-chill pear cultivars of subtropics of India. Present investigation reports the changes in sugar metabolism and related enzymatic activities in fruits of ‘PN’ and ‘PB’ cultivars harvested at different developmental stages from 45 to 150 days after fruit set. Total soluble sugars, fructose, and sucrose contents were higher in ‘PB’ as compared to ‘PN’ during fruit growth and maturation stages. Total phenols and flavanols increased initially and then showed a decreasing trend towards maturity. Sucrose synthase (SS) and sucrose phosphate synthase (SPS) activities strongly correlated to sucrose content in ‘PN’ but SPS was weakly related in ‘PB’ fruits. Acid and neutral invertases showed a negative correlation with sucrose content in ‘PN’, and a reverse trend in ‘PB’ cultivar was observed. It is concluded that SS and SPS are crucial for sucrose accumulation in ‘PN’, but invertase enzymes are also important for sucrose accumulation in ‘PB’ fruits.

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Abstract

Non-alcoholic fatty liver disease is one of the most common chronic liver diseases with unclarified pathomechanism and without evidence-proven therapy. Dietary polyphenols, targeting oxidative stress, are at the center of investigations. Our aim was to examine the effects of a polyphenol rich extract on metal element homeostasis and transmethylation ability in non-alcoholic fatty liver model. A ten-day rat model was used (control group, hyperlipidemic group with fat-rich diet, hyperlipidemic group with fat-rich diet and polyphenol supplementation, N = 8 in each group). The hyperlipidemic diet increased the concentration of the majority of the elements with significantly higher contents of B, Co, Cu, Fe, Mg, Mn, Na, Ni, P, Se, Si, and Zn in the liver. Further elevation of Al, Pb, and Sn concentrations could be observed in polyphenol supplemented animals. The polyphenol supplement unexpectedly decreased the transmethylation ability of the liver (132.00 vs. 114.15 vs. 92.25 HCHO μg g−1) further. The results emphasize the possible role of altered metal and non-metal element concentrations and decreased transmethylation ability in the pathomechanism of fatty liver disease. Dietary supplementation with natural compounds may have undesirable effect as well, there is the necessity to improve the efficacy of polyphenol formulations because of their low oral bioavailability.

Open access
Acta Alimentaria
Authors: K.O. Bartha, L. Csengeri, A. Lichthammer, A. Erdélyi, J. Kubányi, and Zs. Szűcs

Abstract

COVID-19 lockdown affects people's daily routine and has an impact on their lifestyle. Recent studies documented associations between body weight changes and children's lifestyle during social isolation. Childhood obesity is associated with a higher risk of COVID-19 severity and mortality. Our aim was to assess the effects of lockdown due to the COVID-19 pandemic on children's sleep, screen time, physical activity, and eating habits. 387 parents of five elementary school students between 16 and 26 June 2020 were interviewed through an online questionnaire. Physical activity level decreased (63.8%), sleep (60.9%) and screen (5.64 ± 3.05 h/day) times and food intake (39.8%) increased. 80.6% of parents reported changes in children's diet: increased consumption of fruits and vegetables (32.4%), breakfast (15.5%), water and sugar-free beverages (17.6%), snacks (40.4%), sugary drinks (9.9%) was observed. Body weight increased in 44.4% of children. The results of the survey conducted under GYERE®-Children's Health Program are in line with the international literature findings: body weight change during the quarantine is significantly associated with food intake, snacking, sugary drinks, and we also found association with fruit and vegetable consumption and lack of breakfast. Effective strategies and electronic health interventions are needed to prevent sedentary lifestyle and obesity during lockdown.

Open access

Abstract

Cassava is used as a staple food in many developing countries despite its low nutrient density. Fortification of cassava diets is needed for the prevention of malnutrition and achievement of food security. Cassava-soybean complementary foods were formulated from natural and solid state fermented cassava complemented with soybean. The proximate composition, physicochemical properties, nutritional quality, and sensory properties of the samples were determined (Table 2). The moisture content (7.51%) and ash (3.81%) content of the solid state fermented (SSF) cassava flour complemented with un-defatted soybean flour was significantly higher (P < 0.05) than of the other samples. Solid state fermentation (SSF) led to the highest reduction in viscosity (from 2,855 to 2,052 cPs). Average weight gain and protein efficiency ratio (PER) of experimental animals fed SSF cassava were the highest. The colour and aroma of SSF diets and that of fermented cassava samples were similar (P > 0.05). The texture of diets from SSF cassava were inferior (P < 0.05) to the other samples. Solid state fermentation of cassava with Rhizopus oligosporus and supplementation with soybean can be used to produce a complementary food that is nutrient dense and nutritionally adequate, although the texture of the product might need to be improved.

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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