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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.

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Abstract

Both onion and shallot are the most common ingredients to use for many recipes. Consuming onion and shallot provide health benefits including antidiabetic effects. However, the benefits of onion and shallot mixture at different ratios have not been studied in terms of total phenolic content, total antioxidant capacity, superoxide dismutase (SOD)-like activity, and antidiabetic effects. Our study revealed that shallot significantly increased total phenolic content in the mixture from 492 ± 32 μg mL−1 (100% v/v onion) to 803 ± 24 μg mL−1 (100% v/v shallot) depending on the ratios of shallot in the mixture. Shallot also significantly enhanced total antioxidant capacity, SOD-like activity, α-amylase inhibition, and α-glucosidase inhibition in the mixture. Shallot juice exhibited the highest percentage inhibition of α-amylase activity (40.51 ± 1.57%) and α-glucosidase activity (89.61 ± 2.85%) in comparison to those of onion juice and the mixture. In addition, significant positive correlation between phenolic compound and different variables was observed (P < 0.05). Phenolic compounds present in onion and shallot are probably responsible for many health benefits including antidiabetic effects.

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Abstract

Chinese onion (Allium chinense G. Don) is an edible vegetable as well as a traditional Chinese medicine. It is rich in steroidal saponins and possesses broad health benefits. In this study, the optimal extraction protocol of the total saponins from Chinese onion (ACS) was explored, and the content of the total steroidal saponins in ACS reached 56.62%. Network pharmacology was applied to predict the related signalling pathways and targets between the main phytochemicals in ACS and hypercholesterolaemia. Enrichment analysis showed that ACS might intervene hypercholesterolaemia through the PI3K-Akt signalling pathway. Meanwhile, cholesterol-lowering effects were verified by ACS intervention in high-cholesterol diet-induced hypercholesterolaemia in Kunming mice. Compared with the model group, the TC and LDL-C levels of mice were decreased and the HDL-C level increased significantly after administration of ACS at a dose of 200 mg kg−1 day−1. The body weight gain, liver index, and atherosclerosis index all decreased dramatically. ACS could significantly reduce the fat content in the liver and reduce the number of fat droplets from the haematoxylin and eosin (H&E) staining of mouse liver. The immunohistochemical staining indicated that ACS could up-regulate the expression of PI3K protein in the liver, thus playing an anti-hypercholesterolaemic role. This study indicated that ACS exhibited significant therapeutic and preventive effects on hypercholesterolaemia, and exerted anti-hypercholesterolaemia through the PI3K-Akt signalling pathway.

Open access

Abstract

Nutritional problems can be seen in children living separated from their families. This cross-sectional pilot study aimed to evaluate intuitive eating, diet quality, and nutritional status of children living separated from their families. A total of 55 adolescent girls aged 12–18 years participated in the study. Anthropometric measurements, biochemical data, and 24-h dietary recall data were collected. The Intuitive Eating Scale-2 (IES-2) and the Turkish version of the Healthy Lifestyle-Diet (HLD-TR) index were used. Participants were divided into two groups according to their scores on the diet quality index using the 50th percentile. Group 1 consisted of participants with a score of 25 points or less, and Group 2 consisted of participants with a score above 25 points. Waist circumference (72.0 (66–83), 65.0 (60–77)) was significantly higher in Group 1 (P < 0.05). IES–2 score (3.05 (2.85–3.40), 3.30 (3.12–3.90)) and two sub–factors; reliance in hunger and satiety cues (2.80 (1.80–3.40), 4.00 (2.60–4.60)) and body–food choice congruence (2.50 (2.00–3.50), 3.50 (3.00–4.50)) were higher in Group 2 (P < 0.05). After adjustment for body mass index, age, and energy intake, there was a significant positive correlation between IES-2 and HLD-TR scores (P = 0.029). In conclusion, it may be advantageous to resort to strategies that promote intuitive eating to reduce obesity and associated problems in this vulnerable group.

Open access
European Journal of Microbiology and Immunology
Authors:
Navid Dashti
,
Forough Golsaz-Shirazi
,
Haleh Soltanghoraee
,
Amir-Hassan Zarnani
,
Mehdi Mohammadi
,
Danyal Imani
,
Mahmood Jeddi-Tehrani
,
Mohammad Mehdi Amiri
, and
Fazel Shokri

Abstract

Background

Waning immunity and emergence of new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), highlight the need for further research in vaccine development.

Methods

A recombinant fusion protein containing the receptor-binding domain (RBD) fused to the human IgG1 Fc (RBD-Fc) was produced in CHO-K1 cells. RBD-Fc was emulsified with four adjuvants to evaluate its immunogenicity. The RBD-specific humoral and cellular immune responses were assessed by ELISA. The virus neutralizing potency of the vaccine was investigated using four neutralization methods. Safety was studied in mice and rabbits, and Antibody-Dependent Enhancement (ADE) effects were investigated by flow cytometry.

Results

RBD-Fc emulsified in Alum induced a high titer of anti-RBD antibodies with remarkable efficacy in neutralizing both pseudotyped and live SARS-CoV-2 Delta variant. The neutralization potency dropped significantly in response to the Omicron variant. RBD-Fc induced both TH2 and particularly TH1 immune responses. Histopathologic examinations demonstrated no substantial pathologic changes in different organs. No changes in serum biochemical and hematologic parameters were observed. ADE effect was not observed following immunization with RBD-Fc.

Conclusion

RBD-Fc elicits highly robust neutralizing antibodies and cellular immune responses, with no adverse effects. Therefore, it could be considered a promising and safe subunit vaccine against SARS-CoV-2.

Open access

Abstract

Acquired benign tracheoesophageal fistulas and bronchoesophageal fistulas (TEF) are typically associated with granulomatous mediastinal infections, 75% of which are iatrogenic. Candida albicans and Actinomyces are commonly occurring organisms, but are uncommon etiologies of TEF. Normal colonization and the slow growth characteristics of some species of these agents rarely result in infection, mycetoma, and broncholithiasis, and thus, delays in diagnosis and treatment are likely. Few reports describe C. albicans or Actinomyces spp. as the etiology of TEF or broncholithiasis. Herein, we report a case of benign acquired TEF secondary to coinfection of Candida and Actinomyces complicated by the formation of an actinomycetoma and broncholithiasis and a comprehensive literature review to highlight the unique nature of this presentation and offer a diagnostic algorithm for diagnosis and treatment of TEFs. Following a presentation of three months of productive cough, choking sensation, night sweats, and weight loss, a bronchoscopy revealed a fistulous connection between the esophagus and the posterior right middle lobe. Pathology identified a calcified fungus ball and a broncholith secondary to the co-infection of Candida and Actinomyces. This unique presentation of Candida and Actinomyces co-infection and the associated diagnostic algorithm are presented as education and a useful tool for clinicians.

Open access

The new species, Mastigopelma latiffiana G. E. Lee, E. Pesiu et X. L. He, discovered in Pen-insular Malaysia, is described and illustrated as a new addition to the genus Mastigopelma Mitt., of the family Lepidoziaceae. The new species is corticolous, growing on a tree branch in a moist montane forest in Cameron Highlands, Pahang, at 1,900 m alt. It is characterised by the leafy shoots arising from stolons, branches, when present, all ventral-intercalary, and terminal branching lacking; asymmetrical leaves with almost straight ventral margins, rounded to truncate leaf apices, entire-margined leaves, thickened cell walls with nodular trigones, and glistening-homogeneous oil bodies (2–4 per cell); and retuse to blunt teethed underleaf apices. This discovery has increased the total number of known species of Mastigopelma Mitt. to five. An identification key to all the species of the genus is presented.

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The Fissidentaceae is one of the moss families with the genus Fissidens. A species of Fissidens viz., F. pokhrensis has been collected from the Neeliyarkottam sacred grove of Kannur District, which is a new record to the moss flora of Kerala. Sacred groves remain neglected in the study of bryoflora.

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Hyophila involuta (Hook) Jaeg., a sample collected from a natural population in the Biological Garden, Obafemi Awolowo University, Nigeria, was sorted into non-sporophytic and sporophytic gametophytes. This was with a view to investigating the possible influence of sporophyte emergence on the bioactive constituents and the antimicrobial potentials of the moss plant. Aqueous extracts of each of the non-sporophytic and the sporophytic gametophyte samples were prepared, and each was subjected to qualitative and quantitative phytochemical screening, gas chromatography-mass spectrometry (GC-MS) analyses, and antimicrobial potentials tests on selected bacteria and fungi following standard procedures. The results showed both extracts testing positive for alkaloids, cardiac glycosides, saponins, and steroids. Quantitatively, alkaloids and cardiac glycosides concentrations were higher in the non-sporophytic than in the sporophytic gametophytes. Nevertheless, the saponins content was higher in sporophytic gametophytes. GC-MS analyses revealed 40 and 46 bioactive compounds in the non-sporophytic and the sporophytic gametophyte samples respectively. The most prominent compound was 1, 13-tetradecadiene (13.62%) in the non-sporophytic gametophyte but cycloheptasiloxane tetradecamethyl- (13.78%) in the sporophytic game-tophyte. Furthermore, the sporophytic gametophyte extract inhibited the growth of Escherichia coli, Pseudomonas aeruginosa, and Candida pseudotropicalis while the non-sporophytic gametophyte extract only inhibited the growth of P. aeruginosa at a minimum inhibitory concentration of 40 mg/mL except for C. pseudotropicalis (20 mg/mL). This study, therefore, provided insight for investigating the medicinal values of bryophytes and concluded that the emergence of sporophytes on gametophytes of a bryophyte species can vary significantly the synthesis of its biologically active compounds and its antimicrobial activity.

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Xanthoria ectaneoides, usually recognised by its secondary sublobules, is circumscribed in a strict sense using spore size and a molecular phylogeny based on ITS-sequences. The species, earlier considered a synonym of X. aureola, forms a subclade with X. coomae and the new species X. pylyporlykii, described here, whereas X. aureola is positioned in the Xanthoria calcicola subclade. The new species X. pylyporlykii is characterised by a combination of characters typical either for Xanthoria ectaneoides or X. coomae.

Open access