Characterization and selection of probiotic lactic acid bacteria from different dietary sources for development of functional foods

Abstract

IntroductionDietary sources have an abundance of bacteria, mainly lactic acid bacteria (LABs), which have long been regarded as probiotics in humans and animals. Lactic acid bacteria (LAB) have been used as probiotic agents due to their ability to produce a variety of beneficial compounds for cultivars and their status as safe microorganisms.MethodsIn this current study, the lactic acid bacteria (LAB) were isolated from several dietary sources such as curd, pickle, milk, and wheat dough. The principal focus of this study was to determine the survivability of these microorganisms in the gastrointestinal tract and to use promising strains to create probiotic drinks with numerous health benefits. The isolates were identified using a combination of morphological, biochemical, molecular and sugar fermentation patterns, like phenotypic characteristics, sugar fermentation, MR-VP reaction, catalase test, urease test, oxidase test, H2S production, NH3 production synthesis from arginine, citrate utilization, indole test, and 16s rRNA sequencing.ResultsTwo (CM1 and OS1) of the 60 isolates obtained showed the best probiotic results and were identified as Lactobacillus acidophilus CM1 and Lactobacillus delbrueckii OS1. These organism sequences were submitted to Gen bank with accession numbers OP811266.1 and OP824643.1, respectively. The acid tolerance test results indicated that most strains could survive significantly in an acidic environment with pH levels of 2 and 3. Similarly, the salt tolerance test results showed that both Lactobacillus acidophilus CM1 and Lactobacillus delbrueckii OS1 could survive at 4 and 6% NaCl levels significantly. The isolates also showed their ability to ferment sugars such as lactose xylose, glucose, sucrose, and fructose.DiscussionIn conclusion, the study showed that the bacteria isolated from different food sources were indeed probiotic lactic acid bacteria and had probiotic properties. These isolates hold potential for future research in the formulation of millet-based probiotic beverages. However, further studies are required to confirm their effectiveness and safety in improving human health. This research provides a foundation for developing functional foods and drinks that can positively affect human health by incorporating probiotic microorganism.

Isolation and Characterization of Lactic Acid Bacteria from Rice Washing Water Waste

“…Lactic acid bacteria obtained from Bamboo shoots also showed similar results with no black precipitate at the bottom as a result of the Fe to FeS conversion [33]. In line with the research results [34] related to the H2S test results, 60 lactic acid bacteria isolates isolated from different food sources do not have the ability to convert sulfur compounds into sulfide as seen from the absence of darkening of the media. It is possible that sulfide compounds combine with iron compounds to form FeS which is a dark-colored precipitate that makes it difficult for organisms to reduce sulfur compounds to sulfide [32], [35].…”

Screening and characterization of lactic acid bacteria and fermentation of gamma-aminobutyric acid-enriched bamboo shoots

“…Experiments involving the exposure of LAB to acid and bile salts have demonstrated that some strains exhibited survival rates of up to 80% or higher. Conversely, there were strains that displayed limited survivability under these conditions ( Tokatlı et al, 2015 ; Wang et al, 2021 ; Khushboo et al, 2023 ).…”

Physicochemical properties and survival assessment of potential probiotics in a novel dairy drink during storage

“…There has been considerable attention toward LAB due to their capacity to modulate the human host system's response to foodborne pathogens. As a result, there is a current exploration of these bacteria's potential employment as a bio‐preservative agent within the food and dairy sectors, and as an alternative to antibiotics in both human and animal medical treatments and animal breeding initiatives (Boranbayeva et al., 2020 ; Kahieshesfandiari et al., 2021 ; Khushboo et al., 2023 ; Nami et al., 2016 , 2018 , 2022 ).…”

“…Notably acknowledged as generally regarded as safe (GRAS), these bacteria exhibit distinctive attributes that render them exceptionally suitable for the abovementioned applications. In the context of the food sector, especially concerning the production of foundational or starter cultures for diverse dairy products, LAB, particularly Lactobacillus spp., find widespread employment (Khushboo et al., 2023 ). The products obtained from the fermentation of milk with probiotic microorganisms are called “probiotic dairy products.” The main probiotic dairy products are yogurt, fermented milk, and cheese (De Andrade et al., 2019 ; Kılıç et al., 2009 ).…”