Impact of Storage Conditions on the Antibacterial and Antifungal Properties of Essential Oils Extracted from Kinnow Peel

Background: The processing of kinnow (Citrus reticulata) juice generates ۳۰–۳۴% peel waste, which is loaded in bioactive compounds like phenolics, limonin, and pectin. This study examined the antibacterial efficacy and storage stability of essential oil (EO) derived from kinnow peel, emphasizing its prospective use in the food, pharmaceutical, and cosmetic sectors. Methods: Kinnow peels were collected from juice venders of Hisar and Sirsa between December ۲۰۲۲ and January ۲۰۲۳. EO was extracted using four methods: Hydrodistillation (HD), Microwave Assisted Hydrodistillation (MAHD), Ultrasonic Assisted Hydrodistillation (UAHD), and Ohmic Heating Assisted Hydrodistillation (OHHD). The antimicrobial activity was assessed by the well diffusion technique against established bacterial and fungus strains. For the storage study, oils were kept in amber-colored bottles at refrigerator and freezer temperatures for ۱۲ months. Fresh and stored oils were characterized using FTIR and GC-MS analysis. Data were evaluated utilizing ANOVA in SPSS ۲۵.۰, with statistical significance established at p<۰.۰۵. Results: The EO exhibited the strongest antimicrobial activity against Staphylococcus aureus, followed by Pseudomonas aeruginosa. It also exhibits antifungal effects against Aspergillus niger and Candida albicans. FTIR and GC-MS analyses confirmed limonene as the dominant compound. The highest concentrations were found in freshly extracted samples: HD (۹۲.۰۴%), MAHD (۸۵.۱۹%), UAHD (۸۶.۰۹%), and OHHD (۸۵.۱۲%). After ۱۲ months of storage, the limonene content decreased slightly but remained more stable at –۱۰ °C: HD (۸۸.۱۱%), MAHD (۸۴.۲۳%), UAHD (۸۵.۲۴%), and OHHD (۸۴.۴۸%), compared to storage at ۴°C: HD (۸۷.۰۶%), MAHD (۸۵.۶۱%), UAHD (۸۴.۹۰%), and OHHD (۸۴.۱۲%). Conclusion: The EO shown greater efficacy against gram-positive bacteria compared to gram-negative pathogens. Prolonged storage reduced low-molecular-weight compounds, though lower temperatures improved retention. These findings suggest that kinnow peel EO holds promise for applications in food preservation and natural antimicrobial formulations. DOI: ۱۰.۱۸۵۰۲/jfqhc.۱۲.۴.۲۰۴۰۵

کلیدواژه ها:

Oils ، Anti-Bacterial Agents ، Limonene ، Food Preservation