Safety, functional properties and technological performance in whey-based media of probiotic candidates from human breast milk

Regulation and analysis of Simiao Yong'an Decoction fermentation by Bacillus subtilis on the diversity of intestinal microbiota in Sprague-Dawley rats

Background and Aim

Simiao Yong'an decoction (SYD) is a classic traditional Chinese medicine (TCM) prescription that has the effects of clearing heat, detoxifying, promoting blood circulation, and relieving pain. In this study, we investigated the effect of SYD on the diversity of intestinal microbiota after fermentation by Bacillus subtilis.

Materials and Methods

SYD was fermented using B. subtilis. Female Sprague-Dawley rats were randomly divided into the following four groups with six rats in each group: Negative sample group (NS), water exaction non-fermentation group (WE), B. subtilis group (BS), and fermentation liquid group (FL). All rats were orally administered for 14 days. High-throughput Illumina sequencing was used to analyze 16S rRNA expression in rat fecal samples.

Results

A total of 2782 operational taxonomical units (OTUs) were identified in this study, and 634 OTUs were shared among all samples. Bacteroidetes (28.17%-53.20%) and Firmicutes (48.35%-67.83%) were the most abundant phyla identified among the four groups. The abundance of Escherichia and Alistipes was lower in the FL group than in the NS group, whereas the abundance of Bifidobacteria and Lactobacillus was increased in the FL group (p < 0.05). The abundance of Bifidobacterium was significantly upregulated in the FL group compared with the WE and BS groups (p < 0.05).

Conclusion

After fermentation, SYD had a significantly better effect than SYD or B. subtilis. SYD significantly promoted the growth of intestinal probiotics, inhibited the growth of pathogenic bacteria, and maintained the balance of intestinal microbiota in SD rats. This study provides new insights into the development and use of SYD.

Functional Characterization of Lactobacillus plantarum Isolated from Cow Milk and the Development of Fermented Coconut and Carrot Juice Mixed Beverage

Screening probiotics are crucial for assessing their safety, security, and further production of functional foods for human health. The present study aimed to isolate and identify bacteria from raw cow's milk samples that exhibit health benefits upon consumption. We characterized the probiotic properties of Lactobacillus plantarum (also called Lactiplantibacillus plantarum) strains CMGC2 and CMJC7 isolated from cow milk by in vitro study. The strains exhibited tolerance to simulated gastric conditions and were further identified by 16S rRNA sequencing as Lactobacillus plantarum (L. plantarum) CMGC2 and CMJC7. Both isolates were evaluated in vitro for their probiotic attributes, viz. hydrophobicity, autoaggregation, co-aggregation, lysozyme tolerance, antibacterial activity, antibiotic susceptibility, hemolytic activity, and phenol tolerance. The isolates CMGC2 and CMJC7 showed excellent probiotic attributes; hence, both strains were selected to produce coconut and carrot juice mixed beverages (CCMB). The CCMB was evaluated for the pH, acid-production rate, and total viable bacterial counts. The results showed that the CCMB was an excellent medium for the growth of CMGC2 and CMJC7 as it supported adequate growth of organisms (8.93 CFU/mL and 8.68 CFU/mL, respectively) even after 48 h of incubation. In conclusion, CMGC2 and CMJC7 can be used to develop different beverages possessing nutritive and probiotic values, and these beverages can be used for producing unique products.

Human Breast Milk: A Source of Potential Probiotic Candidates

This study focuses on the isolation of lactobacilli/bifidobacteria from human breast milk and their first characterization, in the perspective to find new probiotic candidates to be included in food products. More specifically, breast-milk-isolated strains demonstrated a very good aptitude to adhere to intestinal cells, in comparison with L. rhamnosus GG strain, taken as reference. The same behavior has been found for hydrophobicity/auto-aggregation properties. A remarkable antagonistic activity was detected for these isolates not only against spoilage and pathogenic species of food interest, but also against the principal etiological agents of intestinal infections. Indeed, isolated strains impaired spoilage and pathogenic species growth, as well as biofilm formation by gut pathogens. In addition, breast milk strains were characterized for their antibiotic susceptibility, displaying species-specific and strain-specific susceptibility patterns. Finally, to assess their technological potential, the fermentation kinetics and viability of breast milk strains in pasteurized milk were investigated, also including the study of the volatile molecule profiles. In this regard, all the strains pointed out the release of aroma compounds frequently associated with the sensory quality of several dairy products such as acetic acid, diacetyl, acetoin, acetaldehyde. Data here reported point up the high potential of breast-milk-isolated strains as probiotics.