Many biotechnological processes and products were known to mankind well before the biological species in which they happened were identified and their biochemistry was studied. A good example of it is a fermentation process that yields a variety of wonderful products such as yogurt, kefir, pickles, cheese, etc.6
Fermented dairy products were made for millennia without any knowledge of the underlying microbes (lactic acid bacteria) that do the job of breaking down milk sugar and producing lactic acid. In 2024, the oldest known sample of cheese (dated to the Bronze Age of about 3,300 to 3,600 years ago) was studied and shown to contain the same species of lactic acid bacteria that are currently used in the production of kefir.6
By the end of the 19th century, French microbiologist Louis Pasteur identified lactic acid as the contributing factor in the fermentation of yogurt and British surgeon, Joseph Lister, obtained the first lactic acid bacterial species in pure culture.6
Modern Uses of Lactic Acid Bacteria
Nowadays, natural varieties of lactic acid bacteria have been successfully modified and are well known as efficient producers of many fermented dairy products, beverages, meats and vegetable products and a key source of probiotics.6 This trend reflects a broader shift in biotechnology toward harnessing beneficial microorganisms to enhance food quality, safety and nutritional value.
Many species of lactic acid bacteria are inhabitants of the human body, and they play a very important role in our health and well-being. Because lactic acid bacteria live on the surface of human mucosal membranes and interact with our immune system, they can be used to produce and deliver therapeutic compounds. For instance, lactic acid bacteria were genetically modified to produce the protein interleukin-10 (IL-10) for the treatment of inflammatory bowel disease, interleukin-12 (IL-12) for the treatment of asthma and interleukin-6 (IL-6) for the stimulation of immune response to vaccines.7
Furthermore, researchers used genetic engineering to employ lactic acid bacteria for the production of therapeutic compounds that would fight cancer, prevent tumor metastasis, reduce inflammation, decrease the incidence of type II diabetes, etc.7
Genetic engineering opened the door for new applications of the old and well-known microbial species of lactic acid bacteria for the benefits of us all. As research continues to evolve, we can expect even more innovative uses of these microorganisms to improve health, sustainability and food production in the future.
