Post Harvest Management Of Easily Perishable Horticultural Crops Using Probiotics
Post-harvest management and value-addition is integral to horticultural production for reduction in post-harvest
losses, meet consumer requirements, preserve nutritional quality, optimize the utilization of by-products and create
employment opportunities. Probiotics are live microorganisms that confer a health benefit to the host when administered in
adequate amounts. Strains belonging to Bifidobacterium and Lactobacillus, which are the predominant and subdominant
groups of the gastrointestinal micro biota, respectively, are the most widely used probiotic bacteria and are included in many
functional foods and dietary supplements. Action of probiotics is such that, probiotics ferment sugars and produce organic
acids such as lactic acid and acetic acid. The mixtures of organic acids have a powerful antimicrobial activity at low pH.
Secondary metabolites i.e. ethanol, acetaldehyde, acetoin, carbon dioxide, reuterin, reutericyclin and other germicidal
compounds are produced by probiotics. These low molecular weight components works as growth inhibitory or membrane
disrupting factors against pathogens. Some probiotics strains are able to produce proteinaceous antibiotic like substances
designated as bacteriocins. Bacteriocins are ribosomally coded short peptides and exert antimicrobial action by interfering
with cell wall synthesis and by causing pore formation in cell wall of the target organisms. Hydrogen peroxide is produced
by lactic acid bacteria through the action of flavoprotein - containing oxidases, NADH oxidases and superoxide dismutase.
Low amount of H2O2 oxidize sulphydryl group of surface proteins and enzymes of target organisms. Concurrently they are
“good” bacteria that are added to foods to promote a healthy environment of microorganisms in the digestive tract,
supposedly to aid in digestion and promote good gastrointestinal health. So these probiotics can be used to check postharvest
losses of easily perishable horticultural crops as they are attacked by many bacterial (Pencillium- blue mould) and fungal
(alternaria rot etc.) diseases by pre-harvest and post-harvest sprays of different probiotics.