LAB in a Jar: Probiotics in Filipino Fermented Foods

by: Jewel Christi Umali (Chromoplexy)

Photo from Hakai Magazine

    Buro is a Filipino term for fermentation, which involves preserving raw materials in a solution of vinegar, salt, and other flavorings. Fermentation is essential for isolating probiotic strains because it produces an environment that promotes the growth of beneficial bacteria like lactic acid bacteria (LAB) while limiting the growth of unwanted microbes. This selective pressure promotes the growth of probiotic candidates in the fermentation medium, making them easier to separate and identify. 

    A study was conducted to investigate the probiotic activity of Limosilactobacillus fermentum BIL20 and BIL24 genomes isolated from burong isda, a traditional fermented fish product from Arayat, Pampanga. Researchers procured burong isda (fermented fish) from Pampanga to isolate and examine beneficial LAB. Following a 10-day fermentation period, two promising bacterial strains, BIL20 and BIL24, were isolated, purified, and identified using traditional laboratory procedures and cutting-edge tools such as MALDI-TOF MS and whole-genome sequencing. These procedures established the bacteria's identity and genetic makeup, and subsequent genome analyses evaluated their safety, probiotic ability, and resistance to hazardous compounds. 

    To explore their probiotic potential, the researchers evaluated the ability of the bacteria to thrive under extreme pH and bile conditions, which mimicked the human gut. They also isolated bioactive chemicals, which showed antifungal activity against common infections such as Candida albicans and Aspergillus fumigatus. Finally, the bacterial extracts were analyzed using mass spectrometry to discover possible health-promoting chemicals, emphasizing their potential for usage in functional foods or probiotic medications.

    The genome of L. fermentum LAB-1 demonstrates significant probiotic potential because of its robust carbohydrate metabolism, crucial amino acid production, stress response capabilities, and defense mechanisms such as CRISPR-Cas. It exhibits antibacterial activity through anticipated bacteriocins, and, most importantly, it lacks detrimental antibiotic resistance or virulence genes, indicating its safety for human use. 

    L. fermentum LAB-1 also has the potential to produce vitamin-enriched food, which could help address prevalent vitamin deficiencies. Hossain (2022) and Verce et al. (2020) conducted genomic research demonstrating that LAB-1 and other L. fermentum strains have genes for producing critical B-group and K vitamins, including B1, B2, B5, B6, B7, B9, and K1/2. These vitamins are required for cellular processes such as DNA replication, amino acid synthesis, and methylation, and their deficiency can cause major health problems. While synthetic vitamins are commonly utilized, they may not provide the same physiological benefits as naturally produced ones. As a result, introducing vitamin-producing LAB into food manufacturing provides a long-term and effective strategy for tackling nutrient inadequacies around the world.

    The study highlights numerous key characteristics of L. fermentum LAB-1 that support its probiotic and industrial applications. It exhibits metabolic flexibility via a heterofermentative system and a diverse set of carbohydrate-active enzymes, allowing it to adapt to various conditions. Wei et al. (2025) also mentioned that exopolysaccharide synthesis genes have been linked to enhanced gut health and food texture. Additionally, the strain can produce flavor-enhancing chemicals such as acetoin and butanediol. Its probiotic properties are supported by genes involved in gut adhesion, acid and bile resistance, antioxidant defense, and antibacterial activity. 

    While genomic analysis offers valuable insights, there are some limitations that are yet to be elucidated and explored, such as the possibility of horizontal gene transfer. Although no detrimental genes were discovered, the likelihood of horizontal gene transfer in the gut environment cannot be eliminated, prompting additional research. L. fermentum LAB-1 must comply with regulatory standards and achieve GRAS status before being used in the food and health industries. Its probiotic effects must be validated thoroughly using in vivo studies, its stability and viability must be tested for large-scale production, and the taste and texture of products containing the strain must be evaluated to ensure consumer acceptance. 

    In conclusion, the study provides a comprehensive genomic framework for evaluating the probiotic potential of L. fermentum LAB-1. The discovery of genes associated with metabolic adaptability, stress adaptation, and antibacterial activity makes the strain a promising candidate for functional food applications. However, turning genomic findings into practical applications necessitates extensive functional validation, as well as regulatory and industrial considerations. 

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This article was originally published in the GENEWS May 2025 Issue.