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Are you 'Pro' of your body?

Did you remember those days when you followed your parents to the supermarket, walking down the island fridge and you saw a well displayed colorful 5-pack drinks stacked on one another. ‘Yakult’, at least once in your lifetime you have encountered and consumed a probiotic drink which churns your gut afterwards (in a good way of course!), be it relieving your everlasting constipation or even feeling surprisingly fresh afterwards. Now that you’re here, I bet you must be wondering why it was commercialized to improve your gut health far too many times on the local television back in those days. It’s not false advertising I tell you, as a matter of fact, it’s proven to improve your inner health in a lot of ways significantly.

Probiotics, described as "live microorganisms that offer health benefits when consumed in sufficient quantities," encompass bacteria like bifidobacteria and lactobacilli, which have been long regarded as safe and advantageous for well-being and aesthetics when consumed as food (Afrc, 1989, Morelli & Capurso, 2012). A 2006 report by WHO/FAO highlighted the significant contributions of probiotics to immune, digestive, and respiratory functions, as suggested by recent scientific research (Mori et al., 2016).

Image retrieved from Yakult Malaysia Official Website

Lactobacillus casei strain Shirota (LcS), found in the probiotic drink Yakult, has a long history of safe use and health benefits, particularly in gut health and immune modulation (Matsuzaki, 2003). The mechanisms of LcS in the gut include lowering local pH through lactic acid production and outcompeting pathogenic bacteria. These mechanisms might also apply in the oral cavity, potentially displacing harmful bacteria and producing antimicrobial substances. Although studies on Yakult's oral health benefits are limited, preliminary in vitro research suggests that LcS can inhibit periopathogenic and malodorous bacteria (Benton et al., 2006). A recent study investigated LcS's impact on oral microbiota in denture wearers, revealing transient colonization and no significant effect on acidogenic bacteria. This study aims to explore LcS's transient presence in the oral cavity of healthy individuals, assessing its impact on microbial populations related to caries, periodontal disease, and halitosis, by monitoring changes in salivary and tongue plaque bacteria and malodorous gas levels (Sutula et al., 2013).

Image retrieved from Yakult Honsha Co., Ltd, 1999

In a study conducted by Sutula et al, 2013, they found that the impact of consuming Yakult with LcS for four weeks on the oral microbiota of healthy individuals with complete dentition. It was the first to examine the influence of Yakult consumption on the levels of volatile sulfur compounds (VSCs) in morning breath (Sutula et al., 2013). Additionally, the ability of LcS to colonize and remain on oral surfaces, including in saliva and tongue biofilm, during and after the consumption period, was analyzed using selective culturing and molecular identification techniques (Fujimoto et al., 2008).

Another study by Katao-Kataoka et al, 2016, a double-blind, placebo-controlled, parallel-group study was conducted to evaluate the effects of fermented milk with the probiotic L. casei strain Shirota on the psychological, physiological, and physical stress responses of healthy medical students (Kato-Kataoka et al., 2016). These students were undergoing a nationwide academic advancement exam, providing a naturalistic short-term stress model for the research. As a result, daily intake of probiotics, like L. casei strain Shirota, helps maintain gut microbiota diversity and can alleviate psychological, physiological, and physical stress responses. This prevention can ward off common abdominal issues and support quality of life in healthy individuals facing short-term natural stressors (Kurokawa et al., 2010).

Fundamentally, LcS is a lactic acid bacteria. The primary function of these bacteria is to preserve food by generating lactic acid, acetic acid, ethanol, CO2, and bacteriocin. LAB achieves this preservation by producing substances that inhibit the growth of various microbes. Most of these antimicrobial effects result from the production of lactic and acetic acids and the subsequent drop in pH. Additionally, lactic acid bacteria produce other inhibitory compounds such as hydrogen peroxide, diacetyl, carbon dioxide, reuterin, and bacteriocin (Doran et al., 2004).

Today, numerous processed foods and probiotic beverages are popular due to their health benefits. Yakult is one such probiotic drink, made from fermented milk and containing L. casei strains. Consuming probiotic-rich foods and beverages can help bind to oral microorganisms. Through direct interactions, probiotics compete with existing oral bacteria and produce substances that inhibit harmful bacteria, thereby promoting better oral hygiene (Ningsih et al., 2018).

L. casei offers health benefits because this probiotic bacterium can break down lactose. The lactic acid produced by the LAB species L. casei inhibits the growth of pathogenic bacteria such as Escherichia coli. In the small intestine, LAB competes with E. coli for nutrients, attaches to intestinal epithelial cells, forms colonies, and produces antimicrobial substances, preventing the multiplication of harmful bacteria. Additionally, LAB produces short-chain fatty acids, which stimulate the growth of intestinal epithelial cells, enhancing nutrient absorption in the body. It can also help limit the growth of pathogenic bacteria in the gut. This probiotic species aids in the absorption of vitamins and antioxidants and can eliminate toxic components in food. By producing lactic and acetic acids, L. casei lowers intestinal pH, hindering pathogen growth. These bacteria also enhance mineral absorption, including iron, magnesium, calcium, and zinc. Research indicates that L. casei improves food nutrition by synthesizing vitamins through digestive enzymes like casein phosphatase or lysozyme. Probiotics influence the gastrointestinal tract and systemic immune system, with L. casei being the predominant organism in the gut, capable of modifying allergic and inflammatory reactions. Probiotics work by breaking down long chains of proteins, fats, and carbohydrates, facilitated by special enzymes that split these bonds. This breakdown into micronutrients simplifies absorption in the gastrointestinal tract, providing energy to the microorganisms from the digestion process (Ujilestari et al., 2021).

As technology advances and flourishes, there are many studies that are on the grounds of exploring more beneficial microorganisms for the human body to enhance our immune system on top of the ones we are already consuming. In appreciation of our body, we should also always remember how important it is for us to take care of it by consuming nutritious food and beverages hereon.


Article written by Nur Anis Elias, R&D Associate MBIOS 23/24



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