Spinosyn D

Spinosyn D is a member of the spinosyn family of insecticides, derived from the fermentation of the soil actinomycete Saccharopolyspora spinosa with DT₅₀ value of 14.5 days when incubated aerobically in moist soil^[1]. Spinosyn D is a minor component of commercial insecticide spinosad,along with its more abundant counterpart Spinosyn A^[2].

In vivo, [¹⁴C]Spinosyn D was orally administrated into (25mg/day) goats for 3 days by capsule. Within 24 hours of the last dose, 20% for Spinosyn D was found in the tissues and milk - predominantly the fat, and excretion of the ¹⁴C was mainly via the faeces, 76% from Spinosyn D were found in excreta and intestine. 0.94mg [¹⁴C]Spinosyn D was dosed orally by capsule to 10 Leghorn laying hens, each weighing 1.4kg, daily for 5 days. Within 24 hours of the last dose, for Spinosyn D approximately 82% of the applied ¹⁴C was accounted for (78% in the excreta, 0.6% in eggs, 0.8% in fat, 1.2% in liver, 0.5% in muscle and 0.2% in kidney)^[3]. The persistence and residual toxicity of Spinosyn D was evaluated on tomato foliage. Initial residues were 59.12mg/g when applied at 100% maximum field registered concentration (MFRC) (720mg/L active ingredient) and 45.88mg/g at 50% MFRC. After 40 days, residues decreased to 20.71mg/g and 15.39mg/g, respectively. Spinosyn D caused less 10% mortality in E. varians adults within 10 days of exposure to treated tomato leaves, with no mortality from older residues^[4].

References:
[1] Saunders DG, Bret BL. Fate of spinosad in the environment. Down to Earth.1997.52: 14–20.
[2] Zhao C, Huang Y, Guo C, et al. Heterologous Expression of Spinosyn Biosynthetic Gene Cluster in Streptomyces Species Is Dependent on the Expression of Rhamnose Biosynthesis Genes. J Mol Microbiol Biotechnol. 2017;27(3):190-198.
[3] Kirst H A. The spinosyn family of insecticides: realizing the potential of natural products research. J Antibiot (Tokyo). 2010 Mar;63(3):101-11.
[4] Morales S, Martínez A M, Figueroa J I, et al. Foliar persistence and residual activity of four insecticides of different mode of action on the predator Engytatus varians (Hemiptera: Miridae). Chemosphere. 2019 Nov:235:76-83.

Spinosyn D是一种杀虫剂，属于斯皮诺素家族，由土壤放线菌Saccharopolyspora spinosa发酵产生，在潮湿的土壤中有氧孵化DT₅₀值为14.5天^[1]。Spinosyn D是商业杀虫剂斯皮诺撒中的一种次要成分，与其主要成分Spinosyn A共同存在^[2]。

在体内实验中，通过胶囊口服给药（每天25mg），连续给山羊服用3天[¹⁴C]Spinosyn D。在最后一次给药后的24小时内，发现20%的Spinosyn D存在于组织和牛奶中，主要是脂肪组织，并且放射性碳（¹⁴C）的主要排泄途径是粪便，其中76%的Spinosyn D存在于排泄物和肠道中。另外，将0.94mg [¹⁴C]Spinosyn D通过胶囊每日口服给10只体重为1.4千克的莱亨蛋鸡，连续5天。在最后一次给药后的24小时内，大约82% [¹⁴C]Spinosyn D中的¹⁴C被记录（78%在排泄物中，0.6%在鸡蛋中，0.8%在脂肪中，1.2%在肝脏中，0.5%在肌肉中，0.2%在肾脏中）^[3]。研究了Spinosyn D在番茄叶片上的持久性和残留毒性。在100%最大场注册浓度（MFRC） （720mg/L活性成分）下，Spinosyn D初始残留量为59.12mg/g；在50% MFRC下，初始残留量为45.88mg/g。40天后，残留量分别降至20.71mg/g和15.39mg/g。在接触处理过的番茄叶片10天内，Spinosyn D造成变异大肠杆菌成虫的死亡率低于10%，但未观察到10天后残留物导致的死亡^[4]。