A Note on Prebiotics Strategy to Cope with Current Health Challenges in Human Beings

The current widely used practices of processed food have resulted in elimination of healthy microflora from human gut leading several health issues like chronic constipation, irritable bowel syndrome, colon cancer, obesity, heart diseases and high cholesterol etc. Amongst others, prebiotic approaches have been developed to promote the growth of beneficial bacteria in the gut to treat gut related disorders and improve human health. Importance of prebiotics in maintaining gut microbial diversity, need of novel prebiotics having varied functional properties and their production strategies for commercial applications have been highlighted in this article.


Introduction
Now a day's good health and balanced diet are the leading issues among all human beings. Therefore, great enthusiasm has been observed for the development of new variety of food [1]. Different bioactive nutrients including prebiotics (fructooligosaccharides, galactooligosaccharides, xylooligosaccharides, lactulose) are available as supplements or have been added in the variety of commercially available foods like yogurts and juices. Prebiotics are oligosaccharides and are known as non-digestible dietary fibers, which sustain a healthy microbiome by regulating gut microbiota and by modifying microbiota composition as well [2]. They are also used to restore bacterial homeostasis due to any health hazard in terms of disease [3].
Prebiotics/non-digestible fiber could usually be obtained from several natural foods like cereals, legumes, nuts, many fruits and vegetables [4]. However, because of frequent use of processed and junk food in the whole world, non-digestible fiber has been eliminated from our daily life food. Consequently, gut microflora altered in the gut, which results number of gut disorders in every age group of the humans. Growing research literature shows that dietary fiber not only prevents gut diseases but also reduces the risk of heart disease, diabetes, colon cancer and involved in lowering cholesterol [5,6]. The recommended dose of dietary fiber is 25-30g/day; however, a careful estimation is that dietary fiber consumption by an American adult is 15g/day, which is less than half of the recommended dose. Regardless of using different methods to encourage the use of healthy food, the young generation seems trapped in the taste of junk food, which leads obesity, high cholesterol, heart problems and gut issues like constipation, irritable bowel syndrome and colon cancer in early age [7]. These health issues could be improved by adding non-digestible fiber in the food. In this article we are highlighting the importance, challenges and potential solutions of production of novel prebiotics at commercial level ( Figure 1).

Abstract
The current widely used practices of processed food have resulted in elimination of healthy microflora from human gut leading several health issues like chronic constipation, irritable bowel syndrome, colon cancer, obesity, heart diseases and high cholesterol etc. Amongst others, prebiotic approaches have been developed to promote the growth of beneficial bacteria in the gut to treat gut related disorders and improve human health. Importance of prebiotics in maintaining gut microbial diversity, need of novel prebiotics having varied functional properties and their production strategies for commercial applications have been highlighted in this article.
Keywords: Prebiotics, Fructosyltransferase, Probiotics, Oligosaccharides, Non-digestible dietary fiber. Figure 1: An overview of key problem, current challenge and solution for healthy gut: production of unique prebiotics supplements to support maximum number of gut microbial species is one of the potential dealings of altered gut microflora due to change in eating habits in humans.

Market of Prebiotics
As the importance of prebiotics has been highlighted by

Enzymes for Prebiotic Synthesis
Two groups of prebiotics/fructans, fructans/fructooligo saccharides (FOS) and glactooligo saccharides (GOS) are well known for health benefits in humans [8][9][10]. Because of low amount of these oligosaccharides in natural food, it is required to synthesize these compounds in the laboratory for large scale applications. The pre-requisites for commercial production of oligosaccharides/prebiotics at industrial level requires an efficient method and economical raw material to make product cost effective.
Biosynthesis of FOS is a preferred method over chemical methods to avoid the production of hazardous by products and low product during acid-catalyzed hydrolysis synthesis of FOS [11,12]. A wide variety of microorganisms and plants synthesize fructans. Several bacterial and fungal species are good sources of FOS producing enzymes, which have been divided into two classes: 1. β-Dfructofuranosidase and 2. Fructosyl transferase according to their enzymatic activity and the product they produced [13] (Figure 2).

Am J Biomed Sci & Res
Copy@ Nayla Munawar  [18]. FTase can be produced by different plants and microorganisms [15,19]. Because of easy handling, low cost and production of large quantity of enzyme, microbial FTase are preferred over plant FTase for prebiotics synthesis [20]. Therefore, fructosyltransferases have been isolated from different fungal and bacterial strains for commercial production of fructooligosaccharides [FOS] [21][22][23][24][25]. The type of FOS produced by different fructosyl transferases depend of the origin of the enzyme. Different enzymes are specific for the types of linkages that are synthesized in their respective FOS and polymer products.

Challenge in Prebiotic and Probiotic Relationship
Every FOS produced by plants, microorganisms or in the laboratory cannot be prebiotic. FOS should have certain properties to declare as prebiotic like 1.
They should be resistant to stomach acidic pH and nondigestible by intestinal enzymes, 2. They must be hydrolyzed by gut microorganisms [probiotics], Figure 3: Health benefits of fructooligosaccharides (FOS)/prebiotics: prebiotics can not only be beneficial in gut disorders but also effective against common health problem, like obesity and diabetes, in young generation.

Novel Prebiotics
It has been observed that one type of fiber helps in growth substrates [32]. In the other study, the GH68 genes from Halorubrumsaccharovorum and Natronococcusamylolyticus were expressed in the heterologous host E.coli, and the two recombinant enzymes displayed levan-forming activity [33]. Our research group is also involved in characterizing archaeal FTase genes that may code for novel prebiotic synthesizing enzymes. Thus, in addition to other sources of fructosyltransferases, archaea may also serve a source of novel fructosyltransferase enzymes for the production of unique prebiotics for nutraceutical market.

Conclusion
Prebiotics, also known as non-digestible dietary fiber, are vital for the nourishment of gut microbial species (probiotics) and can be obtained from fiber rich food. However, because of elimination of natural fiberfrom food, by frequent use of junk and processed food, gut microflora has been altered. Abolition of specific microbial species from gut thought to be a potent cause of several diseases in early age. Therefore, addition of prebiotics in food has been emerged as an influential way to maintain growth of gut microflora to contest current health challenges in young generation. All research efforts in the field so far directed at the production of novel oligosaccharides to enhance the growth of diverse population of gut microflora. However, an improved understanding of relation between prebiotics and probiotics is required for the synthesis of better oligosaccharides with varied functional properties.
Moreover, sincere research efforts are recommended to explore the usefulness of archaeal fructosyltransferase enzymes for the production of novel multifunctional prebiotics supplements for goodhuman health.