Prebiotics and synbiotics: Recent concepts in nutrition

Gut flora have a crucial role in metabolizing various nutritional substrates to maintain human health. Several studies on prebiotics and symbiotic have reported to be clinically effective in maintaining the balance of gastrointestinal microbiota to improve health conditions. Therefore, an optimum balance is required in the intestinal microflora of the host. Under certain stress conditions, it may be altered which manifests as gut disorders. Prebiotics from food are the fermentable fiber which selectively feed beneficial bacteria in the intestinal microbiota, to maintain a healthy microbiome environment. Probiotic foods are supplements with live microbes, showing immune-supportive effects in the gastrointestinal tract. However, both pre- and probiotics have been reported to work best in combination. This combined effect of both, results in synbiotics. Prebiotic foodstuff remains unaltered in the gastrointestinal tract, as gastric enzymes cannot act on them. They reach the large intestine intact and are selectively fermented to give beneficial effects. This review focusses on prebiotic foods, their nutritional value, characteristics, safe consumption, therapeutic effects and mechanism of action and their role in synbiotics.