【作者】 王丹；

【导师】 迟德富；

【作者基本信息】 东北林业大学 ， 森林生物工程， 2012， 博士

【摘要】 本文采用复凝聚法成功制备α-蒎烯、黑胡椒精油和叶醇微胶囊缓释剂。1)首先在考察各因素对微胶囊成囊情况和包埋率影响的基础上进行了正交优化实验,得到制备微胶囊的较优工艺。(1)两种方法制备α-蒎烯微胶囊较优的制备工艺是：以壳聚糖-阿拉伯胶为壁材制备α-蒎烯较优的微胶囊制备工艺是：壳聚糖浓度0.2%,阿拉伯胶浓度3.5%,乳化剂含量2.5%,芯壁比1：1,反应温度45℃,pH值为4.5,反应时间60min,搅拌转数770r/min。在较优制备工艺条件下制得的α-蒎烯微胶囊包封率达到为61.70±2.5%,载药量为52.11±2.3%,且囊形圆整、分散较好,粒径集中在分布在8μm左右。以明胶-阿拉伯胶为壁材时制备α-蒎烯微胶囊的较优工艺条件是：复凝聚溶液pH=3.4,壁材浓度2.0%,芯壁比1：1,反应温度45℃,复凝聚反应时间50min,搅拌转数660r/min。在较优制备工艺条件下制得的制备α-蒎烯微胶囊的微胶囊多为规则的球形,表面比较光滑,球形独立完整,没有黏连,包埋率为71.70±1.09%,载药量为56.70±0.09%,微胶囊粒径集中在分布在21μm左右。(2)两种方法制备黑胡椒精油微胶囊较优的制备工艺是：以壳聚糖-阿拉伯胶为壁材制备黑胡椒精油较优的微胶囊制备工艺：壳聚糖浓度0.2%,阿拉伯胶浓度3.0%,乳化剂含量2.0%,芯壁比1：1,反应温度45℃,pH值为4.5,反应时间60min,搅拌转数770r/min。在较优制备工艺条件下制得的黑胡椒精油微胶囊包封率达到为51.70±2.5%,载药量为42.11±2.3%,且囊形圆整、分散较好,粒径集中在分布在7μm左右。以明胶-阿拉伯胶为壁材时制备黑胡椒精油微胶囊的较优工艺条件是：复凝聚溶液pH3.4,壁材浓度2.0%,芯壁比1：1,反应温度45℃,复凝聚反应时间50mmin,搅拌转数660r/min。在较优制备工艺条件下制得的黑胡椒精油微胶囊多为规则的球形,表面比较光滑,球形独立完整,没有黏连,包埋率为69.26%,微胶囊粒径集中在分布在13μm左右。(3)两种方法制备叶醇微胶囊较优的制备工艺是：以壳聚糖-阿拉伯胶为壁材的制备叶醇的较优制备工艺条件：壳聚糖浓度0.2%,阿拉伯胶浓度3.0%,乳化剂含量2.5%,芯壁比1：1,反应温度45℃,pH值为4.5,反应时间30mmin,搅拌转数770r/min。在较优制备工艺条件下制得的叶醇微胶囊包封率达到为73.56%±1.69,载药量为49.7%±2.49,且囊形圆整、分散较好,粒径集中在分布在12μm左右。以明胶-阿拉伯胶为壁材时制备叶醇微胶囊的较优工艺条件：复凝聚溶液pH=3.4,壁材浓度2.0%,芯壁比1：1,反应温度45℃,复凝聚反应时间50min,搅拌转数660r/min。在较优制备工艺条件下制得叶醇的微胶囊多为规则的球形,表面比较光滑,球形独立完整,没有黏连,包埋率为83.01%±2.67,微胶囊粒径集中在分布在19μm左右。2)两种方法所制备的微胶囊红外分析结果显示：壳聚糖与阿拉伯胶,明胶与阿拉伯胶形成凝聚物,芯材α-蒎烯、黑胡椒精油、叶醇存在于所制备的微胶囊中。3)所制备的α-蒎烯、黑胡椒精油、叶醇微胶囊悬浮剂结果是：(1)两种方法所制备的微胶囊悬浮剂配方是：4%的聚乙烯吡咯烷酮和0.1%氯化钠,0.1%的增稠/抗沉淀剂黄原胶,1%的抗冻剂丙二醇,0.05%的防霉剂苯甲酸钠。所制备的微胶囊悬浮率都在90%以上,均符合农药制剂悬浮率的要求。(2)经冷热贮稳定性检测,所制备的微胶囊悬浮剂的外观、流动性几乎没变化,扫描电镜观察微胶囊形态也没有变化,紫外分光光度计检测微胶囊悬浮剂所含的有效成分的含量的变化也在允许范围内,符合FAO规定的标准。(3)采用B-型(NDJ-1)旋转黏度剂分别测定以壳聚糖-阿拉伯胶为壁材和以明胶-阿拉伯胶为壁材所制备的微胶囊悬浮剂结果表明：α-蒎烯分别为121mpa.s和158mpa.s；黑胡椒精油为129mpa.s和167mpa.s；叶醇为114mpa.s和143mpa.s,均符合农药悬浮剂的黏度要求。4)微胶囊悬浮剂的药效及缓释结果：(1)室内检测两种方法所制备的α-蒎烯、黑胡椒精油、叶醇微胶囊悬浮剂的缓释效果可知：包封后的α-蒎烯、黑胡椒精油、叶醇微胶囊悬浮剂中的芯材通过透析袋释放到介质中的速率明显受到抑制,其所制备的微胶囊悬浮剂的缓释效果可达11天以上。(2)两种方法所制备的α-蒎烯、黑胡椒精油、叶醇微胶囊悬浮剂,放置一段时间以后,以明胶-阿拉伯胶为壁材所制备的微胶囊,随着放置时间的增长,凹陷度越来越大。此现象说明,其微胶囊能够有效的控制芯材的挥发；以壳聚糖-阿拉伯胶为壁材制备的微胶囊悬浮剂放置一段时间以后,微胶囊的外形没有变化,切开后其内部为穴状结构,穴状结构为芯材挥发后留下的,同样可证明,壳聚糖-阿拉伯胶为壁材能够成功的包埋挥发物α-蒎烯、黑胡椒精油、叶醇。5)野外生测药效结果表明：两种方法所制备的α-蒎烯、黑胡椒精油、叶醇微胶囊悬浮剂其药效没有受到影响,能够有效的降低芯材的挥发,延长药效时间。更多还原

【Abstract】 This study has successfully prepared slow-release microcapsule of a-pinene, black pepper oil, and leaf alcohol micro sizing agents with the method of complex coacervation.1) First of all, the study had performed the orthogonal experiment after exploring various factors of the influence on the microcapsule capsule and embedding rate, and found a preferred preparation process of the microcapsules.(1) Two better preparation technologies to prepare α-pinene microcapsuleComplex coacervation method with chitosan-gum arabic as wall materials can be effective for micro-encapsulation of core material a-pinene. The optimum conditions of preparation of α-pinene microcapsules are:concentration of0.2%chitosan, gum arabic concentration of3.5%,2.5%emulsifier content the core wall than1:1, the reaction temperature is45℃, pH=4.5, reaction time60min, stirring speed770r/min. Under the best preparation conditions, the microcapsule cladding and drug loading rate reach up to61.70±2.5%and52.11±2.3%, and the microcapsule were capsule-shaped, round, and well-dispersed; the particle size is concentrated in about8μm.Optimum conditions for preparation of a-pinene microcapsules with gelatin-gum arabic as wall material are as follows:complex cohesion solution pH=3.4, wall material concentration of2.0%, the core wall ratio1:1, reaction temperature45℃, complex coacervation reaction time50min, stirring speed660r/min. Under the best preparation condition, the microcapsules are capsule-shaped, rounded, and well-dispersed; encapsulation efficiency reach up to71.70±1.09%and56.70±0.09%drug loading; the particle size of the microcapsules is concentrated in the distribution21μm.(2) Two better preparation technologies to prepare black pepper essential oil microcapsuleThe optimum conditions of preparation of black pepper essential oil by using the Chitosan-Arabia gum as wall material was:Concentration of0.2%chitosan, gum arabic concentration of3.0%,2.0%emulsifier content the core wall than1:1, the reaction temperature is45℃, pH=4.5, reaction time60min, and stirring speed770r/min. Under the best preparation conditions, the microcapsule cladding and drug loading rate reach up to51.70±2.5%and42.11±2.3%, and the microcapsule were capsule-shaped, round and well-dispersed; the particle size is concentrated in about7μm.Optimum conditions for preparation of black pepper essential oil microcapsule with gelatin-Arabia gum as wall material are:complex cohesion solution pH=3.4, wall material concentration of2.0%, the core wall ratio1:1, reaction temperature45℃, complex coacervation reaction time50min, stirring speed660r/min. Under the best preparation conditions, the microcapsules are capsule-shaped, rounded, and well-dispersed; encapsulation efficiency reached69.26%; the particle size of the microcapsules is concentrated in the distribution13p.m.(3) Two better preparation technologies to prepare geranial microcapsule The optimum conditions of preparation of black pepper essential oil by using the Chitosan-Arabia gum as wall material are:concentration of0.2%chitosan, gum arabic concentration of3.0%,2.5%emulsifier content the core wall than1:1, the reaction temperature is45℃, pH=4.5, reaction time30min, and stirring speed770r/min. Under the best preparation conditions, the microcapsule cladding and drug loading rate reach up to73.56%±1.69; drug loading is49.7%+2.49, and the microcapsules are capsule-shaped, round and well-dispersed; the particle size is concentrated in about12μm.Optimum conditions for preparation of geranial microcapsule with gelatin-Arabia gum as wall material: complex cohesion solution pH=3.4, wall material concentration of2.0%, the core wall ratio1:1, reaction temperature45℃, complex coacervation reaction time50min, stirring speed660r/min. The microcapsules capsule-shaped rounded, well dispersed, encapsulation efficiency reached83.01%±2.67, the particle size of the microcapsules is concentrated in the distribution19μm about the best preparation conditions.2) Infrared analysis of the results of the two methods for preparing microcapsule:the chitosan and Arabia gum, gelatin and Arabia formed condensed mixture, and the core material of a-pinene, black pepper essential oil, and cis-3-hexen-l-ol exist in the preparation of microcapsules.3) The results of suspending capsule prepared by the a-pinene, black pepper oil, and leaf alcohol micro sizing agents(1) Suspending formula of microcapsules prepared by the two methods is:4%polyvinyl pyrrolidone and0.1%sodium chloride,0.1%of the thickening/anti-settling agent is xanthan gum,5%of the anti-freezing agent propylene glycol, and0.05%fungicides sodium benzoate. The suspension rate of the microcapsules prepared in the above reaches90%, which is in line with the requirements of the suspension rate of pesticide formulations.(2) Through hot and cold storage stability test, the appearance and fluidity of the microcapsules prepared suspensions almost did not change, and the scanning electron microscope microcapsules morphology did not, either. The change in content of the active ingredients by the UV spectrophotometer microcapsule suspensions also comply with the FAO prescribed standards(3) B-type (NDJ-1) measurement of microcapsule suspensions prepared by chitosan-gum arabic as wall material and gelatin-gum arabic as wall material separately show that the viscosity of the a-pinene is121mpa.s and158mpa.s separately; black pepper oil,129mpa.s and167mpa.s; leaf alcohol microcapsules,114mpa.s and143mpa.s. All of these comply with the viscosity of pesticide suspension requirements of the agent.4) Efficacy and slow-release capsule suspension results(1) Indoor testing prepared by the two methods are a-pinene, black pepper essential oils, the sustained release effect of phytol microcapsule suspensions manefested:encapsulating the a-pinene, black pepper oil, leaf alcohol microcapsule suspensions, the core material is released by the dialysis bag to a medium rate was significantly inhibited and their microcapsules prepared sustained-release effect of the suspending agent of up to11days or more. (2) microcapsule suspensions of α-pinene, black pepper oil, leaf alcohol prepared by two methods, if placed for some time, the morphological changes of the microcapsules of the scanning electron microscope show that:If gelatin-gum arabic as wall material prepared in black microcapsules is placed for3days, the wall will show depression, and with the growth of the storage time, the depression degree as well as the depth of the recess and recessed areas are also increasing. This phenomenon indicates that using complex coacervation of gelatin-gum arabic as wall material can successfully entrapped volatiles alpha-pinene, the essential oils of black pepper, leaf alcohol, and the microcapsules can effectively control the core material volatile; If chitosan-Gum Arabic as the wall material of microcapsules prepared suspensions are placed for some time, the shape of the microcapsules do not change, and its internal is cut to be of cryptand structure, which is left after evaporation of the core material. The same goes to chitosan-gum arabic as wall material, which successfully entrapped volatiles alpha-pinene, the essential oils of black pepper, leaf alcohol.5) The field bioassay pharmacodynamic results show that:the efficacy of microcapsule suspensions prepared by α-pinene, black pepper oil, and leaf alcohol is not affected, and it is possible to effectively reduce the volatilization of the core material, and to extend the efficacy time.更多还原