酶法提取葛根渣中异黄酮的研究

葛粉提取后形成的葛根渣含有活性成分异黄酮,将葛根渣的酶法预处理与乙醇抽提工艺相结合,可使异黄酮的提取率明显提高。以10 g葛根渣为原料,当纤维素酶用量为10 FPIU(以每克葛根渣计,下同),处理12 h后,总异黄酮得率可增至1.14%,为常规醇提法的1.36倍;在木聚糖酶用量为300 IU的条件下,处理6 h后,总异黄酮得率1.28%,为常规醇提法的1.52倍。纤维素酶和木聚糖酶之间存在着协同作用:每克葛根渣采用300 IU的木聚糖酶和7.5 FPIU的纤维素酶协同处理6 h后,总异黄酮得率可达1.38%,为常规醇提法的1.64倍。     

Effects of Foliar Application of Elicitors on Red Clover Isoflavone Content

Red clover (Trifolium pratense L.) contains high concentrations of isoflavones, compounds that have received much interest lately due to their presumed benefits for human health. In this experiment we tested the possibility to induce isoflavone production in the foliage of two greenhouse‐grown red clover cultivars (‘Azur’ and ‘Start’) through the application of elicitor compounds. Foliar applications of different concentrations of acetic acid (50, 100, 250 and 500 mm ), yeast extract (1, 2, 3 and 4 g l^?1), and chitosan (125, 250, 500, and 1000 mg l^?1) were carried out on plants at the late vegetative stage, which were harvested 2 or 8 days after spraying. Concentrations of genistein, daidzein, formononetin and biochanin A were determined by high performance liquid chromatography. The two cultivars differed in isoflavone concentrations, ‘Azur’ having on average 36 % higher biochanin A, formononetin and total isoflavone concentrations than ‘Start’ (P < 0.05). A cultivar × sampling date interaction (P < 0.1) reflected a 20 % increase over time in total isoflavone concentration with ‘Azur’, which was not observed with ‘Start’. Effects of elicitors were limited, contrasts indicating overall, 12, 14 and 15 % greater total isoflavone concentration in yeast extract (P < 0.1), chitosan (P < 0.05) and acetic acid (P < 0.05)‐treated plants, respectively, than in untreated control plants. There were few differences between the various elicitors and none between concentrations of each elicitor.     

浸泡条件对黄豆芽生长的影响及其大豆异黄酮含量

[目的]确定黄豆芽生长的最佳生产条件.[方法]以黄豆芽的发芽率、生长条件为指标,研究黄豆的浸泡加水量、浸泡温度对黄豆芽生长的影响;同时研究大豆异黄酮随黄豆芽生长的变化规律.[结果]试验得出生产黄豆芽的最佳浸泡条件为:加水量2倍豆重,浸泡温度为25℃;发现大豆异黄酮随黄豆芽生长而逐渐增加.[结论]研究可为黄豆芽的生产和营养价值研究提供参考依据.     

大豆异黄酮的功能和开发前景的研究进展

大豆异黄酮是一类具有植物雌激素活性的物质,它主要包括为染料木素,大豆黄素,黄豆黄素。动物实验、临床研究以及流行病学调查表明,大豆异黄酮对癌症、动脉硬化症、骨质疏松症以及更年期综合症具有预防与治愈作用。     

普通烟草IRL基因反义植物表达载体的构建

异黄酮还原酶相似蛋白(IRL)是与异黄酮还原酶具有高度序列同源一致性而功能不同的一类蛋白.通过PCR扩增普通烟草(Nicotiama tabacum)品种龙里红花烟IRL基因的一段特异保守片段NtIRLA,并将其亚克隆到中间载体pCAMBIA2301G中,构建了IRL反义植物表达载体pCAMBIA2301G-IRLA.通过PCR鉴定、酶切鉴定证实载体构建成功,并转化到根癌农杆菌LBA4404菌株中形成工程菌株,为进一步利用转基因手段明确IRL基因在烟草次生代谢中的功能奠定了基础.     

大豆异黄酮对异丙肾上腺素诱导大鼠心肌纤维化的保护作用

目的：观察大豆异黄酮（Soybean isoflavone,SI）对异丙肾上腺素（Isoproterenol,ISO）诱导的心肌纤维化（Myocardial fibrosis,MF）的保护作用.方法异丙肾上腺素皮下注射诱导心肌纤维化模型,经SI低、中、高（30,60,120 mg/kg）3个剂量组和阳性对照卡托普利组（50 mg/kg）治疗后,观察其对心肌细胞直径（MD）、心室重量指数（ HW/BW）、左心室重量指数（ LVI）、羟脯氨酸（ Hyp）含量及心肌组织中钙调神经磷酸酶（ Calcineurin,CaN）活性的影响.结果 SI不同剂量组均能够降低HW/BW和LVI（P〈0.05或P〈0.01）,减少羟脯氨酸含量（P〈0.05或P〈0.01））,减小心肌细胞直径（P〈0.05或P〈0.01）,降低心肌组织中CaN的活性（P〈0.01）,减轻ISO诱导的心肌纤维化.结论 SI对心肌纤维化的保护作用可能与降低心肌组织中钙调神经磷酸酶活性有关.     

植物性类激素物质的营养作用研究与开发前景

本文就日粮中植物性类激素物质的营养作用进行了分析,重点讨论了大豆异黄酮、黄酮等类激素物质的抗肿瘤作用、免疫作用、内分泌作用、对心血管系统的作用等,分析了植物性类激素物质在动物生产中的潜在效应及应用前景。     

Immunological relationship between the New Zealand A and the Australian T strains of infectious bronchitis virus as measured by cross-immunisation tests in tracheal organ cultures from immunised birds

AIM: To determine if exogenous oestradiol or the phyto-oestrogen genistein could reduce food intake in male and female cats fed ad libitum that had been allowed to accrue excessive bodyfat following neutering.

METHODS: Sixteen adult (eight female, eight male) cats were neutered and allowed to increase their bodyweight (BW) through feeding ad libitum of a complete and balanced dry diet. Oestradiol was injected subcutaneously for 5-day periods in incremental doses (0.25–4 µg per cat), then food intake was recorded, and vaginal cytological changes were observed in females. Similarly, genistein was administered orally for 5-day periods in incremental doses (5–100 mg/kg).

RESULTS: In males and females, both oestradiol (p<0.001) and genistein (p=0.037) significantly reduced food intake during treatment, and the minimum daily doses that produced a significant effect were 0.5 µg and 100 mg/kg, respectively. The minimum daily dose of oestradiol that produced a significant effect on food intake was not associated with changes in vaginal cytology over the 5-day treatment period.

CONCLUSIONS AND CLINICAL RELEVANCE: Gonadal oestradiol appeared to be a key modulator of food intake in both male and female cats, and replacement of oestrogen to neutered cats via oestradiol or an oestrogen surrogate such as genistein has potential for reducing the prevalence of obesity in neutered cats.     

大豆异黄酮的生物活性及在畜牧生产上的应用

大豆异黄酮是一类从大豆种中提取的植物雌激素类物质,主要包括染料木黄酮、大豆黄酮和黄豆黄素.已发现大豆异黄酮具有多种生物活性,如对肿瘤、心血管疾病、骨质疏松症和更年期综合症预防与治疗作用,作为动物饲料添加剂在畜牧生产中也有一定的应用前景.文章主要从大豆异黄酮的生物活性及在畜牧生产上的应用进行了综述.     

接种摩西柄囊霉对连作大豆异黄酮及脂肪酸含量的影响

为探索接种摩西柄嚢霉(F. mosseae)对连作大豆籽粒异黄酮及脂肪酸含量的影响,为把F. mosseae应用于连作大豆的生产提供理论依据。试验选用‘垦丰16’（中间型品种,KF16）、‘黑农44’（高脂肪型品种,HN44）和‘黑农48’（高蛋白型品种,HN48）作为试验材料。试验采用盆栽,每盆装风干土12.5 kg,土壤为连作0年(CK)、1年(L1)、2年(L2)的大豆大田土壤。每盆接种F. mosseae菌剂200 g。采用紫外分光光度计法和气相色谱法,对成熟大豆籽粒中异黄酮以及脂肪酸含量进行测定。结果表明：KF16、HN44和HN48分别在L1,L2,L2时,异黄酮含量最高。KF16、HN44和HN48脂肪酸含量随连作年限增加而降低。接种F. mosseae可以提高大豆异黄酮含量,降低脂肪酸含量。