Thumbnail Image

Thesis

Browse

20211
Reset filters
Subject: Chemistry × Author: Dudeja, Isha ×
Reset filters

Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    ThesisItemOpen Access
    Study of Nanoemulsions of Grapefruit Oil and their role in controlling Postharvest Fungus
    (Punjab Agricultural University, Ludhiana, 2021) Dudeja, Isha; Tandon, Ritu
    Among therapeutic and fragrant plant botanicals, essential oils are charming consideration for research, attributable to their huge scope of bioactivities. Utilization of essential oils as antimicrobial agents in fields of food conservation, makeup, agribusiness, drugs and so on is well established. However, their use for development of ecofriendly agrochemicals such as nanoformulations, is yet to be explored. Kinnow, a Citrus crop is hybrid of Citrus deliciosa and Citrus nobilis is grown mainly in Punjab region of India and Pakistan. Its high fruit quality, better juice content and bright orange color makes it the major consumed citrus crop. But owing to mesophillic fungal attacks, the kinnow crop experience post harvest losses leading to nutritional loss and financial losses to farmers. Penicillium digitatum is the most prominent one and majorly contributes to the postharvest losses. Apart from medicinal plants, certain fruit and vegetable wastes of food processing industry also possess potent chemical compounds with antimicrobial properties. Grapefruit (Citrus paradisi or C. paradisi) is a subtropical citrus hybrid originated in Barbados with vast antimicrobial properties. The present study was therefore, aimed to develop grapefruit essential oil nanoemulsions to explore its antifungal potential against Penicillium digitatum. Grapefruit EO was extracted using Clevenger-type apparatus with 0.25% essential oil yield. Compositional analysis of extracted EO by GC-MS revealed presence of 𝜶-limonene (83.73%) as the major compound. Nanoemulsions were prepared by mixing grapefruit essential oil and surfactant (Tween 80) in different ratios (v/v) viz 1:0.5, 1:1, 1:2 and 1:3 by using bath and probe sonicator. The droplet size of nanoemulsions formulated using probe and bath sonication ranges from 60nm -190nm and 120-400 nm respectively. The polydispersity index (PDI) of nanoemulsions formulated using probe and bath sonication ranges from ranges from 0.22-0.26 and 0.24-0.276 respectively, indicating homogeneity produced by both the techniques. All the nanoemulsions formulated possessed the pH in 5-7.04 and the electrical conductivity more than 30μS cm-1. The nanoemulsions with 1:1 O:S ratio (20 min) exhibited the optimum droplet diameter and PDI with maximum stability. Antimycotic potential of grapefruit essential oil and its nanoemulsions [1:1 O:S ratio (20 min)] was evaluated using poisoned food technique which revealed the best efficacy of the naoemulsion against P. digitatum (88.6%) as compared to pure grapefruit peel essential oil (76.6%) treatment. Optical microscopy of grapefruit peel essential oil and nanoemulsion treated fungus also supplemented the antifunagal activity data. The optical micrographs indicated change in morphology with further decrease in hyphal diameter in treated grapefruit peel essential oil nanoemulsions. Further studies need to be conducted to explore the potential of grapefruit peel essential oil nanoemulsions for enhancing shelf life of kinnow fruits.