Evaluation of Antimicrobial and Phytochemical Properties of Agro-Waste and their Potential Applications as Bio-Preservatives and Natural Dyes

Abstract

Around 40% of agro-waste is generated globally every year most of which is not composted due to improper disposal methods, this increases the carbon footprints which in turn causes a great deal of harm to the environment. The aim of this experiment was to evaluate the antimicrobial and phytochemical properties of extracts prepared of lemon peel (Citrus limon), onion peel (Allium cepa) and potato peels (Solanum tuberosum). The project was an attempt to increase sustainability and decrease waste generation by complete utilization of agro-products prior to disposal. The peels were collected from local restaurants and food joints to aid in reduced waste generation. The extracts were prepared using home-based methods; laboratory extraction using Soxhlet apparatus was carried out for lemon peel extract. For the antimicrobial analysis, four organisms were used, two of which were gram positive (Staphylococcus aureus, Bacillus cereus) and two were gram negative (Escherichia coli, Pseudomonas putida). S.aureus was isolated from a poultry source whereas E.coli was isolated from fish drain water. The lemon peel extracts showed a high degree of antimicrobial activity against all the test organisms, whereas the onion peel extracts positively retarded the growth of both the gram-positive test isolates and consecutively, potato peel extracts showed bactericidal effects against E.coli. The extracts were analyzed for presence of phytochemicals namely, tannins, phenols, saponins, flavonoids, vitamin C; promising results were obtained proving the importance and medicinal relevance of the extracts. To check for preservative attributes of the extracts, quantitative and qualitative examinations were conducted, wherein, efficacious results were noted for the lemon peel extracts, however, actions of onion peel extracts and a combination of extracts was culminated to be inconclusive due to excess coloration/ pigmentation. Lastly textile/ fabric dyes were yielded from the prepared extracts, and as observed, the color was retained by the cloth after addition of mordants.