Exploring Technological, Safety and Probiotic Properties of Enterococcus Strains: Impact on Rheological Parameters in Fermented Milk.

Enterococci, known for their resilience, are commonly found in food, the environment, and the gastrointestinal tracts of humans and animals. In recent research, six strains of enterococcus were isolated from bat guano. These include Enterococcus mundtii SRBG1, Enterococcus gallinarum SRBG3, Enterococcus faecium SRBG2, Enterococcus casseliflavus EC1, and Enterococcus devriesei CAU 1344. Identification was done using 16S DNA analysis. Each strain underwent evaluation for its technological properties (such as tolerances to various NaCl concentrations and temperatures, as well as amylolytic, ß-galactosidase, lipolytic, and proteolytic activities, and EPS production) and selected probiotic properties (including safety profile, resistance to 0.3 percent bile salts and gastric juice with a pH of 2.5, lysozyme tolerance, and antibacterial and antibiofilm activities against four foodborne pathogens). The results were analyzed using Principal Component Analysis. This analysis revealed that E. mundtii SRBG1 and E. gallinarum SRBG3, followed by E. faecium SRBG2, were most closely associated with a broad range of technological characteristics and were subsequently used for fermenting skimmed milk. The rheological properties of the samples indicated a shear-thinning or non-Newtonian behavior. Furthermore, during storage of the fermented milk at 4 °C over periods of 1, 7, 14, and 21 days, there were no significant changes in bacterial count (at around 7 log10 CFU/mL) and pH when fermented with the three evaluated strains.

The Impact of Origanum vulgare Supplementation on Human Asthenozoospermic Sperm Parameter Quality.

Male infertility is a complex multifactorial disease and a real health problem; 50% of infertile men have identifiable causes detectable by fundamental sperm analysis. Numerous research studies have shown the possibility of treating abnormal semen samples with some drugs before artificial insemination, yet evidence of the drug's effectiveness remains minimal. In our previous work, we tested the effectiveness of some essential oils, such as eucalyptus (Eucalyptus globulus Labill.), oregano (Origanum vulgare L.), and sage (Salvia officinalis L.) on sperm parameters. The essential oil of oregano showed the best ameliorative effect. In present, we examined the effect of the essential oil of O. vulgare on the physiological parameters and the specific activity of certain antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), lipid peroxidation rate (MDA), and GAPDH and antioxidant and metabolic biomarkers, characterizing the quality of human sperm. The results showed that in vitro supplementation of oregano significantly improves the mobility and antioxidant activities, without harmful effects on the integrity of the sperm's DNA, and that the selected concentration of oregano EO is nontoxic and may be considered a therapeutic alternative to heal sperm motility problems in asthenozoospermic patients.

Optimisation and characterization of α-D-glucan produced by Bacillus velezensis RSDM1 and evaluation of its protective effect on oxidative stress in Tetrahymena thermophila induced by H2O2.

A novel exopolysaccharide was isolated from Bacillus velezensis RSDM1, purified and characterized. The optimization was carried out by Box-Behnken design and the highest yield of EPS-RSDM1 was 1969.53 mg/L. The EPS was composed by glucose with a molecular weight of 1.78 × 104 Da and connected by α-1,6 and α-1,3. The EPS was thermally stable and showed pseudoplastic rheology. The SEM have demonstrated a porous structure. Furthermore, EPS-RSDM1 showed a protective effect against the oxidative stress induced by H2O2 in Tetrahymena thermophila. The exposure of the cells to H2O2 reduced significantly the cell survival and CAT, SOD, GR, SDH and GAPDH activities, and increased the MDA production. However, pretreatment of the cells with EPS-RSDM1 prior to H2O2 exposure elevated the cell survival and enzyme activities, and decreased the level of MDA activity. Our study suggest that EPS-RSDM1 could be useful for preventing cellular oxidation in pharmaceutical and food industries.

Effect of encapsulated probiotic in Inulin-Maltodextrin-Sodium alginate matrix on the viability of Enterococcus mundtii SRBG1 and the rheological parameters of fermented milk.

In the current research, Enterococcus mundtii SRBG1 newly isolated from Bat guano was encapsulated using spray drying technique to create a probiotic powder using six combinations of inulin, maltodextrin and sodium alginate. The encapsulation yield, moisture content, physical characteristics, and shape were investigated. Microcapsules yields ranged from 67 to 85 percent, which is consistent with typical B-290 spray-drier yields. The moisture content showed to increase (4 ± 0.15%) with the addition of sodium alginate to inulin and maltodextrin. In the gastrointestinal conditions (simulated gastric juice and bile salts), it was shown that the viability of probiotic cells in capsules was higher than that of free cells. This demonstrated the effectiveness of combining inulin and maltodextrin to encapsulate substances in surviving in gastro-intestinal conditions. Additionally, we evaluated the non-encapsulated and encapsulated SRBG1 by assessing their impact on the rheological parameters of fermented milk. The results showed that in the absence of sodium alginate the viscosity of milk was lower than with the other protectors, which was confirmed by the quick acidification of the fermented milk by microcapsules containing sodium alginate.

Screening, optimization and characterization of exopolysaccharides produced by novel strains isolated from Moroccan raw donkey milk.

Two exopolysaccharides (EPS) producing strains, isolated from raw donkey milk were identified as Leuconostoc mesenteroides SL and Enterococcus viikkiensis N5 using 16S rDNA sequencing. The Box Benheken design exhibited the highest yield of EPS-SL (672.342 mg/L) produced by SL and of EPS-N5 (901 mg/L) produced by N5. The molecular weight was 1.68×104 for EPS-SL and 1.55×104 Da for EPS-N5. FTIR, NMR and GC-MS analysis showed that the EPS are heteropolysaccharides. The SEM image showed that the EPS-SL was smooth and represented a lotus leaf shape and EPS-N5 revealed a stiff-like, porous appearance and was more compact than EPS-SL. The TGA analyses showed high thermal stability and degradation temperature. Additionally, the two EPSs possessed antibacterial and antioxidant activity, and the EPS-SL had the stronger antioxidant activity. Consequently, these results suggest that the functional and biological properties of EPS-SL and EPS-N5 imply the potential application in the food and pharmaceutical industries.

Isolation and Identification of Dominant Bacteria from Raw Donkey Milk Produced in a Region of Morocco by QIIME 2 and Evaluation of Their Antibacterial Activity.

Recently, the interest in donkey milk has increased considerably because it proved high nutritive and functional values of their ingredients. Its chemical composition is widely studied, but its microbiota, especially lactic acid bacteria, remains less studied. This study focuses on analyzing, isolating, and identifying lactic acid bacteria and evaluating their capacity to produce biomolecules with antibacterial activity. Among 44 strains identified, 43 are Gram-positive, and most are catalase-negative and cocci-shaped. Five strains were selected to evaluate their antibacterial activity against Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli. Different induction methods allowed to amplify the antibacterial effects against these pathogenic strains.

Insights on Health and Food Applications of Equus asinus (Donkey) Milk Bioactive Proteins and Peptides-An Overview.

Due to its similarity with human milk and its low allergenic properties, donkey milk has long been used as an alternative for infants and patients with cow's milk protein allergy (CMPA). In addition, this milk is attracting growing interest in human nutrition because of presumed health benefits. It has antioxidant, antimicrobial, antitumoral, antiproliferative and antidiabetic activity. In addition, it stimulates the immune system, regulates the gastrointestinal flora, and prevents inflammatory diseases. Although all donkey milk components can contribute to functional and nutritional effects, it is generally accepted that the whey protein fraction plays a significant role. This review aims to highlight the active proteins and peptides of donkey milk in comparison with other types of milk, emphasizing their properties and their roles in different fields of health and food applications.

The Effect of Supplementation with Some Essential Oils on the Mobility and the Vitality of Human Sperm.

The objective of this work is to study the improvement effect of some essential oils of sage (Salvia officinalis), oregano (Origanum vulgare), and eucalyptus (eucalyptus globulus) on the physiological parameters characterizing the quality of human sperm (mobility and vitality). We find natural biomolecules to improve sperm quality to increase the chances of success of very low in vitro fertilization (IVF) that stagnate around 20%. Sperm samples were mixed with different concentrations of essential oils. The effect of these essential oils on the motility and vitality of spermatozoa has been analyzed. The mobility was determined using a Computer Assisted Sperm Analysis (CASA). In the other side, the evaluation of sperm vitality was performed by staining eosin 2% and the microscopic examination is carried out via optical microscope. A drop of sperm will be mixed with a drop of eosin solution 2%, spread between the slip and coverslip, then allowed to air dry, and examined under a microscope. A significant improvement in the mobility and vitality of human spermatozoa has been noted with oregano. Eucalyptus after 10 min of exposure also significantly improves the mobility and vitality of the spermatozoa. Sage does not improve mobility for these incubation times but significantly improves vitality.