Department of Chemistry, University of Gujrat, Gujrat, Pakistan.
Institute of Advanced Technology, Universiti Putra Malaysia, UPM, Serdang, Selangor, Malaysia.
PLoS One. 2021 Oct 28;16(10):e0258864. doi: 10.1371/journal.pone.0258864. eCollection 2021.
Pesticides are the leading defence against pests, but their unsafe use reciprocates the pesticide residues in highly susceptible food and is becoming a serious risk for human health. In this study, mint extract and riboflavin were tested as photosensitisers in combination with light irradiation of different frequencies, employed for various time intervals to improve the photo-degradation of deltamethrin (DM) and lambda cyhalothrin (λ-CHT) in cauliflower. Different source of light was studied, either in ultraviolet range (UV-C, 254 nm or UV-A, 320-380 nm) or sunlight simulator (> 380-800 nm). The degradation of the pesticides varied depending on the type of photosensitiser and light source. Photo-degradation of the DM and λ-CHT was enhanced by applying the mint extracts and riboflavin and a more significant degradation was achieved with UV-C than with either UV-A or sunlight, reaching a maximum decrement of the concentration by 67-76%. The light treatments did not significantly affect the in-vitro antioxidant activity of the natural antioxidants in cauliflower. A calculated dietary risk assessment revealed that obvious dietary health hazards of DM and λ-CHT pesticides when sprayed on cauliflower for pest control. The use of green chemical photosensitisers (mint extract and riboflavin) in combination with UV light irradiation represents a novel, sustainable, and safe approach to pesticide reduction in produce.
农药是防治害虫的主要手段，但它们的不安全使用会导致高敏感性食物中残留农药，从而对人类健康造成严重威胁。在本研究中，薄荷提取物和核黄素被测试为光敏剂，与不同频率的光照射相结合，在不同的时间间隔内使用，以提高花椰菜中氯菊酯（DM）和高效氯氟氰菊酯（λ-CHT）的光降解效率。研究了不同来源的光，包括紫外线范围（UV-C，254nm 或 UV-A，320-380nm）或阳光模拟器（>380-800nm）。农药的降解取决于光敏剂和光源的类型。薄荷提取物和核黄素的应用增强了 DM 和 λ-CHT 的光降解，与 UV-A 或阳光相比，UV-C 更能显著提高降解效率，浓度最大降低了 67-76%。光照处理对花椰菜中天然抗氧化剂的体外抗氧化活性没有显著影响。通过计算膳食风险评估发现，当喷洒在花椰菜上用于防治害虫时，DM 和 λ-CHT 农药对饮食会造成明显的健康危害。将绿色化学光敏剂（薄荷提取物和核黄素）与紫外线照射相结合，是一种新颖、可持续和安全的减少农产品中农药残留的方法。
