Abstract：
To achieve a waste-free clean production, the present study aimed to valorize an underused agroindustrial byproduct (rice bran) by mealworms bioconversion and produce bio-oil from pyrolysis of insect excreta (frass) as bioinsecticide. To reach the first goal, the suitability of rice bran (RB) versus standard diet, wheat bran (WB), was examined by determining feed conversion, growth performance, and nutritional profile of T. molitor larvae. RB diet was an appropriate feed substrate for breeding mealworms, as evidenced by their high survival rates, optimal feed conversion parameters, and its capability to support the growth and life cycle of this insect. Besides, RB did not affect soluble larval protein content but modified crude fat content and fatty acid profile. In order to address the second aim, egested frass from RB and WB were subjected to pyrolysis to obtain bio-oils. The main compound was acetic acid (≈37%) followed by 1,6-anhydro-β-d-glucopyranose (from 16 to 25%), as measured by GC-MS analysis. Nitrogen-containing chemicals accounted for ≈10%. Frass bio-oils could represent a novel source of bioinsecticides due to their bioeffectiveness in insect pests of economic importance (Plodia interpunctella and Tribolium castaneum) and medical interest (Culex pipiens pipiens). For P. interpunctella adults, frass bio-oils produced insecticidal activity by fumigant and contact exposure whereas for T. castaneum adults, just fumigant. By a miniaturized model that simulates semireal storage conditions, it was seen that, on T. castaneum, frass RB bio-oil generated higher repellent effect than frass WB. Finally, bio-oils proved to have larvicidal activity against Cx. p. pipiens.
摘要：
实现无废清洁生产,本研究旨在通过粉虫生物转化来提高未充分利用的农业工业副产品（米糠）的价值，并从昆虫排泄物（frass）的热解中产生生物油作为生物杀虫剂。为了达到第一个目标，米糠（RB）与标准饮食的适用性，麦麸(WB),通过确定饲料转化率来检查，增长业绩，和墨虫幼虫的营养概况。RB饮食是繁殖粉虫的合适饲料基质，它们的高存活率证明了这一点，最佳饲料转化参数，以及它支持这种昆虫生长和生命周期的能力。此外,RB不影响可溶性幼虫蛋白质含量，但改变了粗脂肪含量和脂肪酸谱。为了实现第二个目标，将RB和WB中的产物进行热解以获得生物油。主要化合物是乙酸（约37％），其次是1,6-脱水-β-d-吡喃葡萄糖（16％至25％），通过GC-MS分析测量。含氮化学品约占10%。Frass生物油可以代表一种新型的生物杀虫剂来源，因为它们在具有经济重要性的害虫（Plodiaintrunctella和Triboliumcastaneum）和医学价值（Culexpipienspipiens）中具有生物有效性。对于穿刺虫成年人来说，弗拉斯生物油通过熏蒸剂和接触暴露产生杀虫活性，而对于蓖麻成虫，只是熏蒸剂。通过模拟半真实存储条件的小型化模型，人们看到，在蓖麻上，弗拉斯RB生物油产生比弗拉斯WB更高的驱除效果。最后,生物油被证明对Cx具有杀幼虫活性。p.pipiens。
