Molecular and biotechnological characteristics of proteolytic activity from <i>Streptococcus thermophilus</i> as a proteolytic lactic acid bacteria to enhance protein-derived bioactive peptides

The demand for healthy food items with a high nutrient value of bioavailability and bioaccessibility has created a need for continuous development of technology and food ingredients like bioactive peptides. This study aimed to investigate seven proteolytic lactic acid bacteria (PLABs) isolated from the plaa-som (fermented fish) sample originated from silver BARB species for production of proteolytic enzymes. Proteolytic enzymes produced by (PLABs) were used further to create potent bioactive peptides by hydrolyzing proteins throughout PLAB-probiotics enhancer. Protein derived-bioactive peptides was tested the proteolytic activity on different protein sources and examined bioactivities including antioxidative and antimicrobial effect for further use in functional foods. Results of screened-PLAB strains showed high proteolytic activity namely Streptococcus thermophilus strains (KKUPA22 and KKUPK13). These strains have proteolytic system consisting of extracellular and cell-bound enzymes that used for degrading protein in fish flesh protein (FFP) and skim milk (SKM) broth media. Proteolytic activity of tested bacterial enzymes was estimated after incubation at 45, 37, and 50 °C. Furthermore, FFP hydrolysates were formed with various peptides and has small molecular weights (checked by SDS-PAGE) in the range of10.5 to 22 kDa), exhibiting strong activity. Data revealed that S. thermophilus strains (KKUPA22 and KKUPK13) had high antioxidant activity in term of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) radical-scavenging inhibition, and ferric reducing antioxidant power (FRAP) reducing power capacity. Both strains (KKUPA22 and KKUPK13) of S. thermophilus have higher antimicrobial activity against Gram-negative bacteria than against Gram-positive bacteria. We have confirmed presence of proteolytic (prt) gene regions in S. thermophilus strains using specific primers via PCR amplification. Results showed highest homology (100%) with the prtS gene of S. thermophillus located on the cell envelope proteolytic enzymes (CEPEs) such as serine proteinase. Therefore, it concluded that the proteolytic system of tested PLAB strains able to generate bioactive peptides-derived proteins having active biological property, good mechanism of degradability, and bioaccessibility for further use in catalyzing protein of functional foods

Microencapsulation of Mitragyna leaf extracts to be used as a bioactive compound source to enhance in vitro fermentation characteristics and microbial dynamics

Objective Mitragyna speciosa Korth is traditionally used in Thailand. They have a high level of antioxidant capacities and bioactive compounds, the potential to modulate rumen fermentation and decrease methane production. The aim of the study was to investigate the different levels of microencapsulated-Mitragyna leaves extracts (MMLE) supplementation on nutrient degradability, rumen ecology, microbial dynamics, and methane production in an in vitro study. Methods A completely randomized design was used to assign the experimental treatments, MMLE was supplemented at 0%, 4%, 6%, and 8% of the total dry matter (DM) substrate. Results The addition of MMLE significantly increased in vitro dry matter degradability both at 12, 24, and 48 h, while ammonia-nitrogen (NH3-N) concentration was improved with MMLE supplementation. The MMLE had the greatest propionate and total volatile fatty acid production when added with 6% of total DM substrate, while decreased the methane production (12, 24, and 48 h). Furthermore, the microbial population of cellulolytic bacteria and Butyrivibrio fibrisolvens were increased, whilst Methanobacteriales was decreased with MMLE feeding. Conclusion The results indicated that MMLE could be a potential alternative plant-based bioactive compound supplement to be used as ruminant feed additives

Extraction, Characterization, and Chitosan Microencapsulation of Bioactive Compounds from Cannabis sativa L., Cannabis indica L., and Mitragyna speiosa K.

The objective of the research was to investigate the bioactive compounds of herbal plant leaves by microencapsulation technique for future application as a feed additive. In this experiment, three herbal plant leaves, namely Cannabis sativa L., Cannabis indica L., and Mitragyna speiosa K., were comparatively investigated using different methods to extract their bioactive compounds. Two methods were used to extract the bioactive compounds: microwave extraction (water-heating transferred) and maceration extraction (methanol extracted). The results obtained using microwave extraction revealed that the total polyphenolic and flavonoid contents and antioxidant capacity were significantly higher and stronger, respectively, than those produced by the maceration extraction method (p &lt; 0.05). Furthermore, the spray-drying technique was employed to enhance the extracted compounds by encapsulation with chitosan through ionic gelation properties. The physical characteristics of chitosan-encapsulated substrates were examined under a scanning electron microscope (SEM) and were as microparticle size (1.45 to 11.0 &micro;m). The encapsulation efficiency of the bioactive compounds was found to be 99.7, 82.3, and 54.6% for microencapsulated M. speiosa, C. indica, and C. sativa, respectively. Therefore, microwave treatment prior to chitosan encapsulation of leaf extracts resulted in increased recovery of bioactive compound encroachment

Bioaccessibility and Microencapsulation of <i>Lactobacillus</i> sp. to Enhance <i>Nham</i> Protein Hydrolysates in Thai Fermented Sausage

The development of functional food products is increasingly gaining lots of interest and popularity among stakeholders. The aim of this study was to evaluate the bioaccessibility of three Lactobacillus sp. starter cultures, including Lacticaseibacillus casei KKU-KK1, Lactiplantibacillus pentosus KKU-KK2, and Lactobacillus acidophilus KKU-KK3, in order to enhance the performance of the probiotic potential of Nham protein hydrolysates in Thai fermented sausage using microencapsulation technology. Probiotic microcapsules were created from a novel wall material made up of a combination of glutinous rice flour and inulin through a freeze-drying process. Accordingly, the results of three formulations of Nham probiotic and spontaneous fermentation (control) characterized by their physicochemical and microbiological characteristics displayed a correlation between an increase in the amount of total acidity, the population of lactic acid bacteria, and the generated TCA-soluble peptides, while the pH and total soluble protein gradually decreased under proteolysis during the fermentation time. The fractionation of Nham protein hydrolysates (NPHs) was prepared using a microwave extraction process: NPH-nham1, NPH-nham2, and NPH-nham3 (10 mg/mL with fermentation time 114 h), exhibited the highest DPPH radical-scavenging activity and FRAP-reducing power capacity as well, compared to NPH-nhamcontrol at p E. coli TISTR 073, S. aureus TISTR 029, and Ent. aerogenes TISTR 1540). Anti-microbial properties of NPHs peptides against gram-negative bacteria were higher than against gram-positive bacteria. In conclusion, the bioaccessibility of NPHs peptides was significantly enhanced by micro-encapsulation and showed a potential bioactive characteristic for developing into a probiotic agent