Selenium enriched bifidobacteria and lactobacilli as potential dietary supplements

In this study, we tested the ability of lactobacilli and bifidobacteria strains to accumulate and biotransform sodium selenite into various selenium species, including selenium nanoparticles (SeNPs). Selenium tolerance and cytotoxicity of selenized strains towards human adenocarcinoma Caco-2 and HT29 cells were determined for all tested strains. Furthermore, the influence of selenium enrichment on the antioxidant activity of selenized strains and hydrophobicity of the bacterial cell surfaces were evaluated. Both hydrophobicity and antioxidant activity increased significantly in the selenized L. paracasei strain and decreased significantly in the selenized L. helveticus strain. The concentrations of 5 and 10 mg/L Na2SeO3 in the growth media were safer for Caco-2 and HT29 cell growth than higher concentrations. At higher concentrations (30, 50, and 100 mg/L), the cell viability was reduced. All the tested strains showed differences in antioxidant potential and hydrophobicity after selenium enrichment. In addition to selenocystine ​​and selenomethionine, the tested bacterial strains produced significant amounts of SeNPs. Our results show that the tested bacterial strains can accumulate and biotransform inorganic selenium, which allows them to become a potential source of selenium.

Evolving Advances in the Cosmetic use of Probiotics and Postbiotics: Health, Regulatory and Marketing Aspects

Ongoing development in cosmetics is increasingly making use of probiotics, which are defined as "live microorganisms with health-enhancing properties mediated through ingestion or topical application to the host". The observation that several bacterial strains augment normal processes of healthy tissue maintenance, particularly for the skin, has opened up new avenues for the use of bacterial strains in cosmetics. A principal feature of such "cosmeceuticals" is an application of increasing insight into the biochemical nature of the skin's normal microbial flora, also called its microbiome. The opportunity of manipulating the skin microbiome to address various skin disorders has revealed novel routes for treatment. The skin microbiome manipulation approaches to address various skin disorders include skin microbiome transplantation, skin bacteriotherapy, and prebiotic stimulation. Research in this field has revealed that medical outcome-targeted manipulation of skin microbiome bacterial strain makeup may significantly increase skin health and appearance. Commercial availability of probiotic skincare products is rapidly expanding worldwide due to satisfactory laboratory results and public perception of probiotics as being intrinsically more wholesome than other bioactive substances, such as synthetics. Major outcomes of probiotic use include a significant reduction in skin wrinkling, acne and other conditions adversely affecting skin appearance and healthy function. Moreover, probiotics may additionally promote normal skin hydration, resulting in a vibrant and lustrous appearance. Nevertheless, significant technical challenges remain for the full optimization of probiotics in cosmetic products. This article summarizes the evolving nature of this field and explores current probiotic research initiatives, along with regulatory aspects and significant challenges in the manufacturing of cosmetics in the context of market expansion for these products.

Functional Properties of Dunaliella salina and Its Positive Effect on Probiotics

The unicellular green microalga Dunaliella is a potential source of a wide range of nutritionally important compounds applicable to the food industry. The aim of this study was to assess the effect of Dunaliella salina dried biomass on the growth and adherence of 10 strains of Lactobacillus, Lacticaseibacillus, and Bifidobacterium. The immunomodulatory, antioxidant, and cytotoxic effects of D. salina on human peripheral mononuclear cells and simulated intestinal epithelial cell lines Caco-2 and HT-29 were evaluated. Furthermore, the hypocholesterolemic effects of the microalgae on lipid metabolism in rats fed a high-fat diet were analyzed. The addition of D. salina biomass had a positive effect on the growth of nine out of 10 probiotics and promoted the adherence of three bifidobacteria strains to human cell lines. The antioxidant and immunomodulatory properties of D. salina were concentration-dependent. The inflammatory cytokines (TNF-α and IL-6) were significantly increased following Dunaliella stimulation at the lowest concentration (0.5% w/v). Eight week supplementation of D. salina to the diet of hypercholesteromic rats significantly decreased the serum concentrations of LDL-C, VLDL, IDL-B, and IDL-C. D. salina is not cytotoxic in intestinal cell models; it promotes adherence of selected bifidobacteria, it affords immunomodulatory and antioxidant effects, and its addition to diets may help decrease atherosclerosis risk factors.

Revealing Probiotic Potential of Enterococcus Strains Isolated From Traditionally Fermented Chhurpi and Healthy Human Gut

In this study, the two lactic acid bacterial strains Enterococcus durans and Enterococcus lactis previously isolated from soft chhurpi, a traditionally fermented milk product prepared by the indigenous community of Sikkim Himalayas and healthy human gut were used. In this study, we attempted to investigate the probiotic attributes, safety, and health beneficial role, and hypercholesterolemia of Enterococcus durans and Enterococcus lactis. Both probiotic potential strains showed good hypocholesterolemic activity in vitro along with tolerance to acid pH (2 and 2.5), tolerance to three bile salts, oxbile, cholic acid, and taurocholic acid (0.5 and 1%), presence of BSH enzyme and its activity, and cell surface adherence. On assessing for safety, both LAB strains were sensitive to antibiotics and exhibited no hemolytic activity. The probiotic strains were tested in vivo in the Sprague–Dawley rats which were divided into five experimental groups: Normal Control (ND), probiotic strain Enterococcus durans HS03 (BSH-negative) and high-cholesterol diet (HCD1), probiotic strain Enterococcus lactis YY1 (BSH-positive) and high-cholesterol diet (HCD2), and a combination of both strains and high-cholesterol diet (HCD3) and Negative Control (HCD). The probiotic-treated groups HCD1, HCD2, and HCD3 showed a decrease in serum cholesterol levels up to 22.55, 6.67, and 31.06%; the TG and VLDL concentrations were 25.39, 26.3, and 33.21%; reduction in LDL-cholesterol was 33.66, 28.50, and 35.87%; and increase of HDL was 38.32, 47.9, and 41.92%. Similarly, the effects of total cholesterol and TG in the liver, kidney and liver histopathology, liver and body lipid index, and oxidative stress in rat liver were also studied. The fecal lactobacilli were more in the samples of the probiotic-treated groups and their fecal coliform and E. coli counts decreased relatively as compared to the control groups in 0, 7, 14, and 21 days. This is the first report on the probiotic potential of Enterococcus durans HS03 and Enterococcus lactis YY1 strains that gives a new insight into the cholesterol-lowering and probiotic product development with wide health attributes.

Spirulina platensis biomass enhances the proliferation rate of Lactobacillus acidophilus 5 (La-5) and combined with La-5 impact the gut microbiota of medium-age healthy individuals through an in vitro gut microbiome model

This study first evaluated the stimulatory effect of S. platensis biomass on the growth of L. acidophilus and the metabolic activity during fermentation (37 °C, 72 h) in a culture medium. The results demonstrated a higher impact of S. platensis biomass than fructooligosaccharide (FOS), an established prebiotic. Higher L. acidophilus proliferation rates and metabolic activity were observed (lower pH values and higher concentrations of acetic, lactic, and propionic acids) in the presence of S. platensis. Then, we evaluated the effects of the S. platensis biomass (1.5 g, twice a day, 5 days) in association with L. acidophilus (10⁶ CFU/g) on the gut microbiota composition of medium-age healthy individuals through the Simulator of Human Intestinal Microbial Ecosystem (SHIME®) and measurement of metabolites. L. acidophilus (La5) and L. acidophilus + S. platensis (Spi-La5) could positively modulate the intestinal microbiota. The administration of La5 resulted in increases in Bacteroides, Megasphaera, Lactobacillus, and Parabacteroides genus abundance, with a consequent decrease in ammonium ions. The administration of Spi-La5 increased the abundance of the genus Erysipelatoclostridium, Roseburia, Enterococcus, Bifidobacterium, Coriobacteriaceae UCG-003, Enterobacter, and Paraclostridium. The results demonstrate that the intestinal microbiota was differently modified by administrating La5 and Spi-La5 and indicate the latter as an alternative for microbiota positive modulation in healthy individuals.

Algae: Study of Edible and Biologically Active Fractions, Their Properties and Applications

The beneficial properties of algae make them perfect functional ingredients for food products. Algae have a high energy value and are a source of biologically active substances, proteins, fats, carbohydrates, vitamins, and macro- and microelements. They are also rich in polyunsaturated fatty acids, proteins, mycosporine-like amino acids, polysaccharides, polyphenols, carotenoids, sterols, steroids, lectins, halogenated compounds, polyketides, alkaloids, and carrageenans. Different extraction parameters are used depending on the purpose and the substances to be isolated. In this study, the following parameters were used: hydromodule 1:10 and an extraction duration of 1-2 h at the extraction temperature of 25-40 °C. A 30-50% solution of ethanol in water was used as an extractant. Algae extracts can be considered as potential natural sources of biologically active compounds with antimicrobial activity and antiviral properties. The content of crude protein, crude fat, and carbohydrates in U. Prolifera, C. racemosa var. peltata (Chlorophyta), S. oligocystum and S. fusiforme (SF-1) was studied. It was found that C. muelleri (Bacillariophyta), I. galbana (Haptophyta), and T. weissflogii (Bacillariophyta) contain about 1.9 times more omega-3 than omega-6 fatty acids. N. gaditana (Ochrophyta), D. salina (Chlorophyta), P. tricornutum (Bacillaryophyta) and I. galbana (Haptophyta) extracts showed inhibitory activity of varying intensities against E. coli or P. aeruginosa. In addition, algae and algae-derived compounds have been proposed to offer attractive possibilities in the food industry, especially in the meat sector, to evolve functional foods with myriad functionalities. Algae can increase the biological activity of food products, while the further study of the structure of compounds found in algae can broaden their future application possibilities.