Fungi with potential probiotic properties isolated from Fuzhuan brick tea

Several of the fungal species associated with Fuzhuan brick tea(FBT)are considered as potential probiotics,but few studies have investigated the probiotic properties of these fungi.Here,we isolated 18 fungal strains from two types of FBT and identified these strains based on internal transcribed spacer(ITS)fragment sequence similarity to reference strains(sequence similarity>98%).Of the 18 strains,10 tolerated simulated human digestive conditions for sufficient periods in vitro:pH 2-3,0.3%-0.5%(m/V)bile salts,and artificial gastrointestinal juices.We then measured the antimicrobial activity of the remaining 10 strains against 5 enteropathogenic bacteria and tested the bacteriostatic effects of the thalli and fermentation broth extracts.Of the 6 strains with strong bacteriostatic effects,we eliminated Eurotium cristatum S-9 due to its low hydrophobicity of(26.12±0.35)%.Finally,2 exhibited good adhesion abilities to human cells(>100%).Notably,2 strains can survive in vivo,because they can be isolated from C57BL/6 mice feces.Thus,2 strains,Aspergillus cristatus H-1 and A.cristatus H-5,are herein identified as promising candidate probiotic strains.It may be put forward a novel research focus on evaluating potential probiotic fungi from FBT.

Separation and Preliminary Identification of Intestinal Probiotics of Laying Hens

[Objective] The paper was to isolate and identify probiotics in the intestine of laying hens. [Method] The intestinal probiotics in laying hens at peak period were isolated using conventional separation methods; the physical and chemical properties of target strains and in vitro antibacterial effects were measured. Moreover, the safety test of chicks was conducted. [Result] Four strains of lactobacillus were isolated from the jejunum of laying hens, including Lactobacillus plantarum, Bacillus acidophilus, L. delbrueckii subsp. Delbrueckii and L. delbrueckii subsp. Lactis, and their inhibition zone diameters were 18.30, 16.07, 11.45, 17.26 mm, respectively. One strain of Lactobacillus, L. brevis, was isolated from the cecum, with the inhibition zone diameter of 10.26 mm. Three strains of bacillus were isolated from the cecum, including Bacillus subtilis, B. cereus and B. licheniformis, and their inhibition zone diameters were 9.25, 8.46 and 8.37 mm, respectively. Daily drinking 2 billion units of viable bacteria was the safe dosage for chicks. [Conclusion] Eight strains of probiotics had certain inhibitory effect on Escherichia coli O;, and had no toxic side effects to chicks. Lactobacillus had strong antibacterial effect on E. coli O;, while the antibacterial effect of bacillus was relatively weak.

Probiotic properties of lactic acid bacteria isolated from traditionally fermented Xinjiang cheese

Six lactic acid bacterial （LAB） strains were isolated from traditionally fermented Xinjiang cheese and evaluated for functional and probiotic properties and potentials as starter cultures. The isolated six LAB strains com- prised Lactobacillus rhamnosus （one strain）, Lactobacillus helveticus （one strain）, and Enterococcus hirae （four strains）. All of the six strains were tolerant to acidic and bile salt conditions. Among which, the L. rhamnosus R4 strain showed more desirable antimicrobial, auto-aggregation, and hydrophobic activity. In addition, the strain L. rhamnosus R4 exhibited the highest level of free radical scavenging activity （53.78% of 1,1-dipheny1-2-picrylhydrazyl （DPPH） free radicals and 45.79% of hydroxyl radicals）. L. rhamnosus R4 also demonstrated cholesterol and triglyceride degrada- tion by 50.97% and 28.92%, respectively. To further examine the health-promoting effects of these LAB strains on host lifespan, Caenorhabditis elegans was used as an in vivo model. Worms fed LAB as a food source had significant differences in lifespan compared to those fed Escherichia coil OP50 （as a negative control）. Feeding of L. rhamnosus R4 extended the mean lifespan of C. elegans by up to 36.1% compared to that of the control. The results suggest that the strains isolated from Xinjiang fermented dairy products have high potential as starter cultures in the cheese industry.

Three lactic acid bacteria with anti-obesity properties:In vitro screening and probiotic assessment

The worldwide obesity epidemic has imposed human being a huge burden and attention had been drawn to manipulating the lactic acid bacteria (LAB) to improve obesity symptoms.In this study,a more comprehensive and reliable in vitro method was established to screen LAB with greater potential against obesity.Firstly,twenty-eight human feces-derived LAB strains were selected by assessing bile salt-acid tolerance and cholesterol lowering capacity.Subsequently,the triglyceride lowering capacity,bile salt hydrolase (BSH) activity,α-glucosidase activity inhibition capacity and Enterobacter cloacae (E.cloacae) growth inhibition capacity were tested for further evaluating the anti-obesity properties of LAB strains.Principal component analysis (PCA) of these results indicated that Limosilactobacillus reuteri (L.reuteri) NCUH003,Lactiplantibacillus plantarum (L.plantarum) NCUH046 and Limosilactobacillus fermentum (L.fermentum) NCUH068 exhibited favorable anti-obesity properties.Besides,the LAB displayed good gastrointestinal adaptability and antioxidant activity but no hemolytic activity,and they were sensitive to various antibiotics.These results indicated that L.reuteri NCUH003,L.plantarum NCUH046 and L.fermentum NCUH068 are potential for application in obesity treatment.