Department of Horticultural Sciences, Faculty of Agriculture, Shiraz University, Shiraz, 71441-65186, Iran.
Medicinal Plants Processing Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Environ Sci Pollut Res Int. 2020 Dec;27(36):45844-45858. doi: 10.1007/s11356-020-10405-y. Epub 2020 Aug 16.
This work describes efforts to encapsulate savory (Satureja hortensis L.) essential oil (EO) with different natural polymers (i.e., Arabic gum/gelatin (AGG), apple pectin (AP), gelatin (G)) and, as a separate set of experiments, with bio cross-linkers (i.e., citric acid and transglutaminase enzyme). The phytotoxic activity of encapsulated savory EO on tomato (Lycopersicon esculentum Mill.) and amaranth weed (Amaranthus retroflexus L.) was investigated. The micro-capsules were evaluated in terms of size, polydispersity, stability, encapsulation efficiency, morphology, and release properties. The Korsmeyer-Peppas model operated when EO was being released from the micro-capsules. Carvacrol (52.5%) and γ-terpinene (30.2%) comprised the main constituents of the savory EO. Based on the results, encapsulating the EO with cross-linked biopolymers increased the stability and herbicidal activity of EO, as compared to simple EO emulsions. Maximum toxicity injuries (MTI) were caused by encapsulations of apple pectin, cross-linked with APe enzyme (15 ml/L) on both plant species. MTI were observed 2 days after using the micro-encapsulated herbicides (MCHs). However, the injury caused by MCHs on tomato was not significant. The lowest values of fresh weight (2.80 g), chlorophyll a (0.194 mg/g Fw), and total chlorophyll content (0.219 mg/g Fw) of amaranth occurred in response to APe (15 ml/L). Moreover, using AP(e) (10 ml/L) caused the lowest values of starch (0.444 mg/g Fw) and flavonoid contents (4.18 mg Cat/g Fw) in amaranth which measured as 59% and 90% reductions, respectively, in comparison with the control. The highest values of MDA (0.0109 nmol/g Fw) and HO (0.0432 μmol/g Fw) were observed in amaranth plants treated with AP(e) (10 ml/L). In summary, cross-linked apple pectin can perform well in slow release delivery systems of agrochemicals. It can be recommended for use in the production of commercial, EO-based natural herbicides.
本工作描述了使用不同天然聚合物（即阿拉伯胶/明胶（AGG）、苹果果胶（AP）、明胶（G））和生物交联剂（即柠檬酸和转谷氨酰胺酶）包封草药香芹精油（EO）的努力。研究了包封香芹 EO 对番茄（Lycopersicon esculentum Mill.）和苋菜杂草（Amaranthus retroflexus L.）的植物毒性活性。根据尺寸、多分散性、稳定性、包封效率、形态和释放特性对微胶囊进行了评估。当 EO 从微胶囊中释放时，Korsmeyer-Peppas 模型起作用。香芹精油的主要成分是香芹酚（52.5%）和γ-萜品烯（30.2%）。基于这些结果，与简单的 EO 乳液相比，用交联生物聚合物包封 EO 可以提高 EO 的稳定性和除草活性。在两种植物上，使用交联苹果果胶（APe 酶 15ml/L）进行包封时，最大毒性损伤（MTI）最高。使用微封装除草剂（MCH）后 2 天观察到 MTI。然而，MCH 对番茄造成的伤害并不显著。苋菜中鲜重（2.80g）、叶绿素 a（0.194mg/gFW）和总叶绿素含量（0.219mg/gFW）的最低值出现在 APe（15ml/L）的响应中。此外，使用 AP(e)（10ml/L）导致苋菜中淀粉（0.444mg/gFW）和类黄酮含量（4.18mg Cat/gFW）的最低值分别降低 59%和 90%，与对照相比。用 AP(e)（10ml/L）处理的苋菜中 MDA（0.0109nmol/gFW）和 HO（0.0432μmol/gFW）的最高值分别为 0.0109nmol/gFW 和 0.0432μmol/gFW。综上所述，交联苹果果胶可以在农药的缓慢释放输送系统中表现良好。它可以推荐用于生产商业的、基于 EO 的天然除草剂。
