Application of microencapsulated isoflavone into milk

This study was designed to develop a microencapsulated, water-soluble isoflavone for application into milk and to examine the hypocholesterolemic effect of such a milk product in a rat diet. The coating material was medium-chain triglyceride (MCT) and the core material was water-soluble isoflavone. The microencapsulation efficiency was 70.2% when the ratio (w/w) of coating material to core material was 15:1. The isoflavone release from the microcapsules was 8% after 3-day storage at 40 degrees C. In in vitro study, 4.0-9.3% of water-soluble isoflavone in simulated gastric fluid was released in the pH range of 2 to 5 after 60 min incubation; however, in simulated intestinal fluid at pH 8, 87.6% of isoflavone was released from the capsules after 40 min incubation time. In sensory analysis, the scores of bitterness, astringency, and off-taste in the encapsulated isoflavone-added milk were slightly, but not significantly, different from those in uncapsulated, isoflavone-added milk. In blood analysis, total cholesterol was significantly decreased in the isoflavone-added group compared with that in the control after 6-week feeding. Therefore, this study confirmed the acceptability of MCT as a coating material in the microencapsulation of water-soluble isoflavone for application into milk, although a slight adverse effect was found in terms of sensory attributes. In addition, blood total cholesterol was lowered in rats which had been fed a cholesterol-reduced and microencapsulated, isoflavone-added milk for 6 weeks.     

SHORT COMMUNICATION Microencapsulation of the water-soluble pesticide Monocrotophos by an oil in oil interfacial polyaddition method

Abstract

A rotatable central composite design was applied to the formulation of poly(butyl 2-cyanoacrylate) nanoparticles with the aim of modifying some physico-chemical properties of these carriers in a controlled way. The joint effect of stabilizer concentration and monomer concentration on the mean particle size, on the electrophoretic mobility and on the polymer molecular weight has been investigated. The results demonstrate that the particle size is only dependent on the stabilizer concentration, nevertheless the electrophoretic mobility and the molecular weight distribution were affected simultaneously by the monomer and the stabilizer concentrations. Moreover, using the response surface diagrams it is possible to deduce the experimental conditions to design particles with the desired properties.     

Microencapsulated ascorbic acid for milk fortification

The present study was designed to develop a microencapsulated L-ascorbic acid and iron that could be used to fortify milk and to determine the sensory properties of milk fortified with microencapuslation. Coating material was medium-chain triacylglycerol (MCT), and selected core material was ferric ammonium sulfate and L-ascorbic acid. The highest efficiency of microencapsulation was 95.0% in the ratio of 15:1 as coating to core material. Ascorbic acid release was increased sharply up to 5 d storage as 6.5%. TBA value was the lowest when both capsulated iron and ascorbic acid were added during 12 d storage, compared with other treatments. In sensory analysis, most aspects were not significantly different between control and capsulated ascorbic acid fortified milk at 5 d storage. The present study indicated that the use of microencapsulated ascorbic acid with MCT is effective for fortifying milk. In addition, these results suggest that acceptable milk products can be prepared with microencapsulated ascorbic acid and iron.     

微胶囊技术及其应用

近年来微胶囊技术在各行业中得到广泛应用,受到人们的普遍关注。本文综述了微胶囊技术的特点及多种微胶囊的制备方法,并介绍了微胶囊的应用及其最新研究进展。     

Microencapsulation of gentamicin in biodegradable PLA and/or PLA/PEG copolymer

Biodegradable carriers containing gentamicin for local treatment of bone infection were developed. This paper describes the preparation and in vitro evaluation of these biodegradable implants. Poly-l-lactic acid (PLA) and polyl-lactic acid/polyethylene glycol (PLA/PEG) disk implants containing gentamicin sulphate were obtained by compression of microspheres prepared by a double emulsion process. The mean particle size distribution of the microspheres, based on volume, ranged from 95-270 µm. The gentamicin sulphate loading of the microspheres, after a methylene chloride-water extraction procedure, exceeded 90% of the theoretical value. In vitro dissolution studies on the microspheres and implants with drug loadings 10-40% w/w indicated that the rate of drug release from both PLA and PLA/PEG implants increased, with an increase in drug loading. The release of gentamicin from microspheres was dependent on the properties of PLA and/or PLA/PEG. The PLA/PEG copolymer was more hydrophilic than the PLA homopolymer, and with a smaller pH change in the microenvironment with polymer being degraded. In comparison, the PLA/PEG implant released antibiotic faster and had a larger inhibitory zone based on the Bauer-Kirby experiments used to test the inhibitory activity of antimicrobial devices. Experimental results showed that the biodegradable PLA/PEG gentamicin delivery system had a potential for prophylaxis of post-operative infection.     

Hydrolysis of isoflavone in black soy milk using cellulose bead as enzyme immobilizer

The establishment of a catalytic system to enrich isoflavone aglycones in black soybean milk was investigated in this study. Beta-glucosidase, which was covalently immobilized onto cellulose beads, exhibited a significant efficiency for the conversion of 4-nitrophenyl β-d-glucuronide to p-nitrophenol over the sol–gel method. The Michaelis constant (K_m) of the cellulose bead enzymatic system was determined to be 1.50 ± 0.10 mM. Operational reusability of the cellulose bead enzymatic system was justified for more than 10 batch reactions in black soy milk. Moreover, the storage stability verification indicated that the cellulose bead catalytic system was able to sustain its highest catalytic activity for 10 days. High-performance liquid chromatography results demonstrated that this enzymatic system required only 30 minutes to achieve complete isoflavone deglycosylation, and the aglycone content in the total isoflavones in black soy milk was enriched by 67% within 30 minutes by the cellulose bead enzymatic system.     

Microencapsulation of probiotics by efficient vibration technology

The target site of action of probiotics is the intestine. They must be surviving the stomach acidic condition before reaching the target site. Three probiotic bacteria were microencapsulated in sodium alginate beads using a sophisticated microencapsulation technology provided by BÜCHI B-390. This study reports the tolerance of the different microencapsulated Lactobacillus at low pH using simulated gastric juice, comparing it with the tolerance of free bacteria. The three microencapsulated strains displayed time-dependent acid sensitivity at pH values under 3.0. At pH 2.0, a dramatic reduction in bacterial survival occurred after 5?min, with only L. casei surviving after 30?min, with 75% survival. At pH 2.5 microencapsulated L. casei survived for 90?, L. reuteri survived for 60?and L. bulgaricus survived for only 30?min, respectively. The microencapsulation technology used in this study may effectively protect Lactobacillus from gastric conditions and permit comparisons between strains.     

Disposition and biotransformation of the estrogenic isoflavone daidzein in rats.

Daidzein is an estrogenic isoflavone present in many plants and therefore consumed in relatively high doses by humans. Daidzein has a low affinity for the estrogen receptor (3 orders of magnitude lower than estradiol) and has been demonstrated to have estrogenic effects in rodents after administration of high doses. We have studied the disposition and biotransformation of daidzein in rats fed a diet low in isoflavone content. Four male and four female Fischer 344 rats were orally administered 100 mg/kg daidzein; excreted urine and feces were collected for 96 h and unchanged daidzein as well as formed metabolites were quantified by HPLC. In urine of male rats, daidzein, daidzein-glucuronide, and daidzein-sulfate were excreted; in females, only unchanged daidzein and daidzein-glucuronide were present. Total urinary excretion of daidzein accounted for < 10% of dose in both males and females. The major pathway of daidzein elimination was excretion of unchanged daidzein with feces. Reductive daidzein-metabolites likely formed by intestinal microflora (equol, O-desmethylangolensin) were excreted with feces in small amounts (< 5% of dose). Excretion of daidzein and metabolites with urine and feces was rapid with elimination half-lives of less than 12 h; daidzein concentrations in urine and feces were below the limit of detection 36 h after daidzein administration. The results suggest that daidzein is only poorly absorbed from the gastrointestinal tract in rodents. Absorbed daidzein is rapidly eliminated both unchanged and as conjugates with urine. The inefficient absorption of daidzein from the gastrointestinal tract and the rapid excretion may explain the weak estrogenicity of daidzein seen in vivo in rodents when compared to other estrogenic chemicals with comparatively low affinity to the estrogen receptor.     

大豆异黄酮苷元滴丸的制备和含量测定

目的:研究大豆异黄酮苷元滴丸的处方、制备工艺和含量测定方法.方法:用单因素实验法确定制备工艺中的各种条件;用正交设计法优选处方组成;用HPLC法测定异黄酮苷元的含量.结果:最佳工艺条件为:冷凝剂二甲基硅油温度10℃,药液温度80℃,滴距6 cm,滴速15滴/min.染料木素在3.6～36%、6.00%和0.89%.结论:本制备工艺稳定性好、成型率高,建立的含量测定方法可控性强、专属性高.     

大豆异黄酮抗骨质疏松症的实验研究及作用机制的探讨

目的 观察大豆异黄酮的抗骨质疏松作用,并探讨其作用机制。方法 (1)切除10月龄大鼠双侧卵巢,3个月后分为己烯雌酚组、模型组、大豆异黄酮高、中、低荆量组,并灌胃,每日1次,连续3个月;用切除双侧卵巢旁部分脂肪的假手术同龄大鼠作对照(对照组)。测定各组动物的骨形态学指标、血清雌二醇(E2)、血清骨源性碱性磷酸酶(BALP)、血清钙磷、骨钙磷、尿钙磷以及子宫系数。(2)用含药血清培养成骨细胞,以MTT法检测成骨细胞增殖情况。结果 (1)大豆异黄酮能明显增加去卵巢大鼠骨小梁平均宽度、单位面积骨小粱骨细胞数、骨皮质平均厚度、股骨头平均吸光度和股骨干平均吸光度;明显升高血清E水平：明显降低血清BALP值;明显增加血清钙、骨钙含量：明显增加子宫系数。(2)大豆异黄酮能明显促进成骨细胞增殖。结论 大豆异黄酮具有明显的抗骨质疏松作用,其作用机制可能与其拟雌激素作用、提高体内雌激素水平、提高机体对钙的吸收与利用、促进成骨细胞DNA合成和生长增殖有关。     

大豆异黄酮研究概况

介绍近年来大豆异黄酮研究概况,包括大豆异黄酮的提取分离、含量测定、生理活性及其在体内的吸收代谢。     

The microencapsulated ascorbic acid release<Emphasis Type="Italic">in vitro</Emphasis> and its effect on iron bioavailability

The present study was carried out to examine the stability of microencapsulated ascorbic acid in simulated-gastric and intestinal situation in vitro and the effect of microencapsulated ascorbic acid on iron bioavailability. Coating materials used were polyglycerol monostearate (PGMS) and medium-chain triacylglycerol (MCT), and core materials were L-ascorbic acid and ferric ammonium sulfate. When ascorbic acid was microencapsulated by MCT, the release of ascorbic acid was 6.3% at pH 5 and 1.32% at pH 2 in simulated-gastric fluids during 60 min. When ascorbic acid was microencapsulated by PGMS, the more ascorbic acid was released in the range of 9.5 to 16.0%. Comparatively, ascorbic acid release increased significantly as 94.7% and 83.8% coated by MCT and PGMS, respectively, for 60 min incubation in simulated-intestinal fluid. In the subsequent study, we tested whether ascorbic acid enhanced the iron bioavailability or not. In results, serum iron content and transferring saturation increased dramatically when subjects consumed milks containing both encapsulated iron and encapsulated ascorbic acid, compared with those when consumed uncapsulated iron or encapsulated iron without ascorbic acid. Therefore, the present data indicated that microencapsulated ascorbic acid with both PGMS and MCT were effective means for fortifying ascorbic acid into milk and for enhancing the iron bioavailability.     

Microencapsulation of allopurinol by solvent evaporation and controlled release investigation of drugs

Abstract

The microencapsulation of drugs is gaining importance in many research activities. A common technique for preparing microcapsules is the solvent evaporation method which is simple but has a large number of reaction control parameters. This study reports the microcapsulation of allopurinol by the solvent evaporation method and the release of the drug from the microcapsules. The effect of concentration of poly(vinyl alcohol) (as a surfactant), molecular weight of ethyl cellulose and stirrer speed in the preparative method were studied. The effect of molecular weight of ethyl cellulose and particle size on drug release were also investigated. It has been found that the drug release is decreased with increasing molecalar weight of polymer and increasing particle size.     

补骨脂中新异黄酮成分的分离与结构鉴定

目的研究补骨脂的化学成分。方法用色谱法分离化合物，根据理化性质和光谱数据鉴定结构。结果分离鉴定了6个化合物：补骨脂素(1)，异补骨脂素(2)，补骨脂查耳酮(3)，补骨脂定(4)，大豆苷(5)，补骨脂异黄酮苷(6)。结论化合物6为新化合物，化合物5为首次从该植物中分离得到。     

水溶性壳聚糖的抑菌作用研究

本文采用固体培养基体外抑菌法,观察了水溶性壳聚糖对细菌生长的影响。结果表明,一定浓度的水溶性壳聚糖对大肠杆菌、金黄色葡萄球菌、枯草杆菌,八叠球菌及放线菌5406有不同程度的抑制作用,对以上5种菌株的最小抑制浓度分别为：0.5%、0.3%、0.5%、0.3%、0.5%。实验结果也表明,经高温处理的水溶性壳聚糖的抗菌作用稳定,对即食调味海带具有保鲜防腐的效果。     

大豆异黄酮对雌性大鼠内分泌功能的影响

目的动物实验观察大豆异黄酮对雌性大鼠内分泌功能的影响。方法12周龄雌性大鼠42只随机分配为三组：低剂量组每日灌胃大豆异黄酮40mg·kg^-1·d^-1,高剂量组每日灌胃大豆异黄酮80mg·kg^-1·d^-1,对照组灌胃0．9％氯化钠注射液。14d后颈静脉取血,采用化学发光法分别测定促卵泡生成素（FSH）、促黄体生成素（LH）、雌二醇（E2）和孕酮（P）四项指标。结果大豆异黄酮低剂量组、高剂量组和对照组三组FSH分别为（0．13±0．02）mIu／ml、（0．12±0．02）mIu／ml、（0．15±0．02）mIu／ml,LH分别为（0．17±0．03）mlu／ml、（O．15±0．04）mIu／ml、（0．18±0．05）mIu／ml,三组相比较差异无统计学意义（P〉0．05）;三组E2分别为（0．09±0．03）nmol／L、（0．03±0．03）nmol／L、（0．12±O．04）nmol／L;P分别为（1．43±0．27）ng／ml、（2．82±0．37）-s／ml、（0．67±0．56）ng／ml。三组相比较大豆异黄酮组的E2活性明显降低（P〈0．01）,尤其高剂量组的降低更为显著。大豆异黄酮组的P水平较对照组明显升高（P〈0．01）,而高剂量组P的升高更为显著。结论大豆异黄酮对大鼠的垂体激素无明显影响,不同剂量的大豆异黄酮可能通过雌激素活性和抗雌激素活性而影响雌性大鼠卵巢激素的分泌调节。     

大豆异黄酮对糖尿病大鼠肾脏的保护作用及其机制

目的探讨大豆异黄酮(SI)对糖尿病大鼠肾脏保护作用及其机制。方法建立链脲佐菌素诱导的糖尿病大鼠模型,将模型大鼠随机分为糖尿病组(DM组)、大豆异黄酮低[40 mg/(kg·d),SI1组]、中[120mg/(kg·d),SI2组]、高[360 mg/(kg·d),SI3组]及正常对照组(NC组)。8周末检测大鼠血糖、24 h尿蛋白、肾指数、总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、血清肌酐(SCr)、血尿素氮(BUN)水平;Western blot检测肾组织nephrin表达。结果 SI3组尿蛋白(0.88±0.15)mg·d-1、肾指数(4.16±0.36)mg·g-1与DM组尿蛋白(1.26±0.45)mg·d-1、肾指数(6.13±0.76)mg·g-1比较明显降低(P<0.05);SI2组TC(2.07±0.52)mmol·L-1、TG(0.99±0.07)mmol·L-1、LDL-C(0.75±0.03)mmol·L-1和BUN(13.37±5.393)mmol·L-1与DM组TC(2.75±0.47)mmol·L-1、TG(1.36±0.35)mmol·L-1、LDL-C(0.83±0.01)mmol·L-1、BUN(24.32±6.31)mmol·L-1比较亦有明显降低(P<0.05);Western blot结果显示DM组nephrin蛋白表达较NC组显著降低(P<0.05),但SI使nephrin蛋白表达增加(P<0.05),且呈剂量依赖性。结论 SI保护糖尿病大鼠肾脏的机制可能部分与增加nephrin表达有关。     

A new phenylpropanoid and a new isoflavone glycoside from Shenqi Fuzheng Injection

A new phenylpropanoid and a new isoflavone glycoside were isolated from Shenqi Fuzheng Injection. Their structures were elucidated as (αS)-α-ethenyl-4-hydroxy-3-methoxy-benzenemethanol (1) and calycosin 7-O-[α-d-glucopyranosyl (1 → 4)]-β-d-glucopyranoside (2) by means of spectroscopic methods including UV, IR, HR-ESI-MS, and NMR. The absolute configurations of 1 and 2 were confirmed by quantum chemical calculation and acid hydrolysis.     

大豆异黄酮活性组分对阿尔茨海默病小鼠抗氧化作用的研究

目的:探讨大豆异黄酮活性组分对阿尔茨海默病(Alzheimer’sdisease,AD)小鼠的抗氧化作用。方法:取10月龄的小鼠,以D-半乳糖和三氯化铝复制AD模型小鼠,用本实验室制备的大豆异黄酮活性组分灌胃15d后,眼球取血,测定血清中超氧化物歧化酶(SOD)、乳酸脱氢酶(LDH)和丙二醛(MDA)的含量,观察脑内海马组织切片神经元细胞的形态改变。结果:与模型组小鼠相比,实验组小鼠血清SOD活力显著提高(P<0.01)、血清LDH含量显著升高(P<0.05)、血清MDA含量明显降低(P<0.01),海马区神经元细胞数量也显著增多,形态改善。结论:异黄酮活性组分能有效地改善衰老AD小鼠的抗氧化系统的功能。     

大豆异黄酮对华法林在人体内药动学和药效学的影响

目的:研究大豆异黄酮对华法林在人体内药动学和药效学的影响。方法:采用随机、单盲、双周期交叉、安慰剂对照试验设计。12名健康志愿者(男女各半)随机分为2组,连续5 wk每日分别服用大豆异黄酮胶囊(75 mg)或安慰剂1粒;d 29口服单剂量华法林5 mg;第2周期2组交叉服用安慰剂或大豆异黄酮胶囊,其余给药方案不变。按要求收集志愿者血样,分别以高效液相色谱(HPLC)法测定华法林的血药浓度以及半自动血凝仪测定常见凝血指标。结果:合用大豆异黄酮后,华法林的药动学参数c_(max)、AUC_(0～144)、AUC_(0～∞)、t_(1/2)显著增加(P<0.05),CL(F)显著域小(P<0.05),t_(max)和V_d(F)没有显著变化;华法林的药效学参数均无显著变化。单独服用大豆异黄酮4 wk后,凝血酶原时间(PT)和活化部分凝血活酶时间(APTF)无显著变化。结论:大豆异黄酮可影响华法林的药动学,但不影响华法林的药效学;单独服用大豆异黄酮4 wk对凝血功能无明显影响。