The term probiotic essentially means anything that is pro-life or pro-health. However, probiotics are microorganisms that are good for health when ingested by humans or other animals. The World Health Organization (2001) defines probiotics as live micro-organisms which, when administered in adequate amounts, confer a health beneﬁt on the host.
The concept of probiotics is attributed to Élie Metchnikoff (1907), a zoologist and Nobel Laureate from Russia. Basically the concept entails replacing pathogenic or harmful bacteria with beneficial ones. More recently, however, the concept has expanded to augmentation of gastro-intestinal flora that gets damaged due to the excessive use of antibiotics. There are a number of benefits attributed to the use of probiotics including (but not limited to) reduction in gastro-intestinal pathogenic organisms, replenishment/maintenance of useful indigenous intestinal microbiota, and improvement of immune system etc.
Though the concept of probiotics is relatively new, use of microbes directly or indirectly could be considered as old as human civilization. We are certainly aware of the fermented food products like yogurt and cheese. We do recognize the health and allied benefits of such foods but seldom consider that together with yogurt and cheese we are eating millions and millions of microbes i.e. bacteria and fungi. Likewise, vaccines and antibiotics are mostly the products of microbial origin. New developments are, however, to deploy microbes within our guts to carry out certain jobs in situ. Interesting enough, life of almost all animals is dependent on the gut biome that they rear and sustain to do different jobs for them. Take the example of termites, earthworms and even nematodes. They harbour special function microbes to sustain life. Termites apparently eat away lignocellulosic materials causing immense damage to the wooden infrastructure and agricultural fields. However, they are able to do this through the agency of microbes in their guts.
Interestingly the concept of probiotics has expanded to overall maintenance of human health including skin care. For example, a visit to MotherDirt will reveal interesting products for skin care based mainly on probiotics. In this case, the underlying idea is to use beneficial microbes that are friendly to natural biome of skin. These friendly bacteria are obtained from soil or so-called dirt which is aptly described as mother dirt. We also understand that human skin provides a good surface for a multiplicity/diversity of microbes (skin microbiome; approximately 1000 species belong to 19 phyla) that are of soil origin. As anywhere else, these microbes develop a kind of commensal and/or synergistic/mutualistic relationship with the skin and any mal-treatment e.g. use of chemicals-based skin care formulations may harm this association. In order for the skin to remain healthy, its biome needs to stay in good health as well. Herein the concept of using probiotics becomes applicable. It is bound to mature and gain popularity in the years to come; presently being at a stage of infancy, so to say.
Looking back into the history and even in present times, clay/dirt facial or whole-body mask is considered a healthy (or health giving) proposition. Whether are not the benefits that accrue from these masks can be attributed to any microbes is not clear but the “mother dirt” has been in action and in use since times immemorial. It is only recently that it is considered a source of health giving organisms i.e. probiotics. Indeed, we all are aware that mother earth is the source of all livelihood and most of the life (marine life being an exception). The food we eat and the infrastructure we see around are all derived from earth in one or the other form; thus the reason to use the term mother earth or little more specifically mother dirt.
It is amazing that a concept that has its origin from human beings is being applied to all sorts of systems. Take for example the soil that represents top 15 cm layer (under most situations). It abounds in microbial life of immense diversity. Like animal gut, micro- as well as macro-biome of soil is required to be in good shape to main soil health and functionality. As with animal gut, if something goes wrong with the native biome, probiotics are considered to be the upcoming solution. A similar is true for soil that has undergone serious damage in terms of its biome due to injudicious use of chemicals for the so-called improvement in productivity and yields. It is not long ago that biofertilizers (microbes-based formulations) were introduced to help improve soil health, fertility, and productivity. Microbes included in these formulations are considered beneficial for different soil functions including acquisition as well as release of essential nutrient elements; synthesis of metabolites and products of immense significance notwithstanding. More recently, however, such formulations are being termed as probiotics and multiplicity of companies have surfaced with the claims to introduce microbes with immense benefit to the health of soil. It would appear, therefore, that the term biofertilizers is fast becoming redundant and taken over by probiotics.
An interesting homology has recently been introduced whereby soil was termed as living skin. Like human and animal skin, soil abounds in microbes that are main agents of life/functionality there and make the soil a living entity in true sense of the meaning. Soil health and care is therefore considered akin to skin care and thus the use of probiotics. This is besides the fact that soil is the sole source as well as depository of beneficial organisms.
In view of above it would appear that beneficial organisms are bound to be the most sought out entities deployed or to be deployed for the human welfare and health care. They stand a good chance to replace nasty chemicals used in our daily life, be it maintenance of soil health, production of food (agriculture), or wellbeing of life on the planet earth. Thus we need to explore further the connection between nature and health. Exploring the connection between nature and health: It’s in the Dirt! Bacteria in soil may make us happier, smarter.