Polyphenols have credentials to tackle the oxidative stress. Oxidative stress is the imbalance between free radicals production and antioxidant enzymes ability to tackle these radicals resulting the onset various metabolic related disorders. Polyphenols based foods have credential as a shield against these glitches mainly owing to their antioxidant potential. In this context, tea polyphenols have gained paramount attention of scientific community as therapeutic agents for the prevention and treatment of various oxidative stress induce maladies owing to their structural diversity, strong antioxidant ability and capacity to modulate various expression involved in the pathogenesis of these maladies. The notable polyphenols are catechins which are mainly present in green tea and further subdivided into various compounds like ECG, EGC, EGCG which has their unique therapeutic potential. The catechins undergo various structural changes and transformed into theaflavins and thearubigins in the process of black tea formation. These are high molecular weight polyphenols and promising candidates in obesity, diabetes and cancer treatment. Mechanistically, these polyphenols ameliorate oxidative stress by trapping the noxious radicals like superoxide and peroxyl, promote the activity of glutathione, suppressing the malondialdehyde (MDA) activity. The current chapter is an attempt to highlight the therapeutic potential of tea polyphenols.
Part of the book: Polyphenols
Microorganism contamination at various stages of food chain is one of the major causes for food spoilage that ultimately leads to food waste, increasing food insecurity issues and substantial economic losses. Various synthetic chemical preservatives are being used to control microbial food spoilage and to extend product shelf life. Researchers and consumers are discouraging the use of synthetic preservatives due to their negative health impacts. Naturally occurring antimicrobials have gained attention among researchers and food manufacturer due to their safety and nontoxic status. Natural preservatives are easy to obtain from plants, animals and microbes. These naturally occurring antimicrobial agents can be isolated from indigenous sources using various advanced techniques. Natural preservatives such as nisin, essential oils, and natamycin have effective potential against spoilage and pathogenic microorganisms. The regulations regarding the use of these naturally occurring preservatives are not well defined in some developing countries. This chapter focuses on source and their potential role, antimicrobial mechanism in food preservation, and current knowledge on the subject.
Part of the book: Active Antimicrobial Food Packaging