Probiotic Characteristics of Streptococcus thermophilus and Lactobacillus bulgaricus as Influenced by New Food Sources.

The current research aimed to evaluate the potential effects of Solanum mammosum, Dioon mejiae, and Amanita caesarea on Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus survival and performance after exposure to different harsh conditions such as bile, acid, gastric juice, and lysozyme to mimic the digestive system from mouth to the intestine. Probiotic protease activity was observed to evaluate the proteolytic system. Probiotics were cultured in a broth mixed with plant material, and after incubation, the results were compared to the control sample. Therefore, plant material's total phenolic compound, total carotenoid compound, antioxidant activity, sugar profile, and acid profile were obtained to discuss their impact on the survival of probiotics. The results indicate that Amanita caesarea negatively affected probiotic survival in the bile tolerance test and positively affected Lactobacillus bulgaricus in the protease activity test. Otherwise, the other plant material did not change the results significantly (p > 0.05) compared to the control in different tests. Consequently, Solanum mammosum and Dioon mejiae had no significant effects (p > 0.05) in increasing probiotic survival.

Attributes of Culture Bacteria as Influenced by Ingredients That Help Treat Leaky Gut.

Consumers are becoming aware of functional ingredients such as medicinal herbs, polyphenols, mushrooms, amino acids, proteins, and probiotics more than ever before. Like yogurt and its probiotics, L-glutamine, quercetin, slippery elm bark, marshmallow root, N-acetyl-D-glucosamine, licorice root, maitake mushrooms, and zinc orotate have demonstrated health benefits through gut microbiota. The impact of these ingredients on yogurt starter culture bacteria characteristics is not well known. The objective of this study was to determine the influence of these ingredients on the probiotic characteristics, tolerance to gastric juices and lysozyme, protease activity, and viability of Streptococcus thermophilus STI-06 and Lactobacillus bulgaricus LB-12. Acid tolerance was determined at 0, 30, 60, 90, and 120 min of incubation, whereas bile tolerance was analyzed at 0, 4, and 8 h. The microbial growth was determined at 0, 2, 4, 6, 8, 10, 12, 14, and 16 h of incubation, while protease activity was evaluated at 0, 12, and 24 h. The application of marshmallow root, licorice root, and slippery elm bark improved bile tolerance and acid tolerance of S. thermophilus. These ingredients did not impact the bile tolerance, acid tolerance, and simulated gastric juice tolerance characteristics of L. bulgaricus over 8 h and 120 min (respectively) of incubation. Similarly, the growth of S. thermophilus and L. bulgaricus was not affected by any of these functional ingredients. The application of marshmallow root, N-acetyl-D-glucosamine, and maitake mushroom significantly increased the protease activity of S. thermophilus, whereas the protease activity of L. bulgaricus was not affected by any ingredient. Compared to the control, marshmallow root and quercetin samples had higher mean log counts and log counts for S. thermophilus on the simulated gastric juice and lysozyme resistance in vitro test, respectively. For L. bulgaricus, licorice root, quercetin, marshmallow root, and slippery elm bark samples had higher log counts than the control samples.