乳酸菌的降血糖作用研究进展

目前乳酸菌的防治糖尿病功效已得到广泛认可.本文综述国内外关于乳酸菌应用于临床糖尿病治疗的研究进展,对乳酸菌可能的降血糖作用机理及物质基础进行了分析总结,并对目前存在的安全性问题和今后研究方向进行探讨,希望为糖尿病防治提供新的思路,为开发新型降糖药物提供一定的理论依据.     

5种药用植物对小鼠的降血糖作用

对菊叶三七(GnuradivaricatiumO.Hoffm.)、仙鹤草(AgrimoniapilosaLedeb.)、夏枯草(PrunellavulgarisL.)、女贞子(LigustrumlucidumAit.)和枸骨(IlexcornutaLindl.etPaxt.)的降糖作用进行了初步的研究。菊叶三七鲜样的水提物(0.2和0.4g kg)及95%乙醇提取物(0.2和0.4g kg)对正常小鼠的血糖有显著的降低作用,干样95%乙醇提取物(0.5、1.0和2.0g kg)对四氧嘧啶糖尿病小鼠的血糖有显著的降低作用,其中鲜样95%乙醇提取物(0 4g kg)的降糖作用优于优降糖,干样95%乙醇提取物(2.0g kg)的降糖作用与降糖灵(0.1g kg)相当。仙鹤草的水煎液(30和60g kg)对正常小鼠的血糖有显著的降低作用,95%乙醇提取物(30、60和120g kg)对四氧嘧啶糖尿病小鼠的血糖均有一定的降低作用。夏枯草的95%乙醇提取物(30、60和120g kg)和女贞子的95%乙醇提取物(11.25和22.50g kg)对四氧嘧啶糖尿病小鼠的血糖均有一定的降低作用。枸骨的正丁醇提取物(30和60g kg)对四氧嘧啶糖尿病小鼠和正常小鼠的血糖均没有影响。实验结果表明,菊叶三七是一种值得开发的降糖植物资源。     

青钱柳对四氧嘧啶糖尿病小鼠降血糖作用的研究

目的：研究我国特有植物保健食品青钱柳对实验性糖尿病小鼠的降解作用,方法：选用昆明种小鼠尾iv四氧嘧啶,选择性破坏胰岛β细胞,造成小鼠实验性糖尿病模型,尔后用青钱柳提取物给该小鼠灌胃,测定其空腹血糖,观察小鼠血糖及体重变化,最后进行糖耐量实验。结果：给小鼠饲喂试验样品4周后,服用青钱柳70％醇提取物及糖复合物的2组小鼠空腹血糖均明显低于模型对照组（P＜0．05）,同时,糖耐量明显增加且对小鼠体重增长无影响,结论：青钱柳对试验性小鼠具有显著的降血糖作用,作为天然保健食品开发具有广阔的前景。     

褐蘑菇碱提物降血糖作用研究

目的：研究褐蘑菇碱提物的降血糖作用。方法：四氧嘧啶灌胃造高血糖小鼠模型,随机分成6组,分别是正常对照组、模型对照组、高剂量组、中剂量组、低剂量组、阳性对照组,前两组以生理盐水连续灌胃7d,阳性对照组灌胃消渴丸溶液连续7d。高、中、低剂量组（100、200、400mg/kg）以褐蘑菇碱提物溶液连续灌胃7d,摘眼球取血,测定空腹血糖值。结果：高、中、低剂量组对糖尿病小鼠的降糖率分别是16.9%、20.2%和15.1%,阳性对照组的降糖率是25.1%。结论：褐蘑菇碱提物中剂量组降糖效果要优于高、低剂量组。褐蘑菇碱提物能显著降低四氧嘧啶所制备的糖尿病小鼠血糖浓度。     

银合欢叶提取物降血糖作用的实验研究

采用四氧嘧啶糖尿病小鼠模型及肾上腺素和葡萄糖引起的高血糖小鼠模型,观察银合欢叶提取物对实验动物的降血糖效果。银合欢叶提取物对四氧嘧啶所致糖尿病小鼠有明显的治疗效果,对肾上腺素和葡萄糖引起的高血糖模型小鼠有明显的降血糖作用,但对正常小鼠血糖无明显影响。     

茶叶不同提取成分降血糖作用的研究与比较

目的:探讨茶多糖、茶多酚、茶色素对血糖的降低作用.方法:用链脲佐菌素(STZ)建立糖尿病小鼠模型.提取茶多糖,茶多酚,茶色素,作用于糖尿病小鼠.通过葡萄糖氧化酶法(GOD-POD)测定血糖含量,研究并比较各成分的降血糖作用.结果:茶多酚,茶色素具有明显的降血糖作用,茶多糖的降血糖作用不明显.结论:茶多糖,茶多酚,茶色素均具有降血糖的作用.     

具有降血糖作用植物的研究进展

本文概述了近二十年国内外报道的具有降血糖作用植物药的研究进展。     

桑叶不同化学成分的降血糖作用

桑叶是一种重要的降血糖药用植物资源。以秋桑叶中提取的六种活性化学成分为材料,研究了六种提取物对四氧嘧啶诱导的糖尿病小鼠的降血糖效果。结果显示,各提取物均有一定的降血糖作用,其中以桑叶总多糖的功效最为显著,桑叶生物碱及桑叶黄酮苷类效果次之。     

锈毛草莓积雪草合剂对STZ小鼠降血糖作用研究

采用75%乙醇萃取锈毛草莓及积雪草,制备成合剂,通过STZ诱导建立糖尿病小鼠模型,随机分为模型组、低剂量组及高剂量组,分别以蒸馏水、4及8 g·kg~(-1)锈毛草莓积雪草合剂灌胃,1次·d~(-1),持续4周,另设正常组作为对照。探究绣毛草莓积雪草合剂对糖尿病小鼠的降血糖效果及作用机制。结果表明:(1)不同剂量的锈毛草莓积雪草合剂均能显著降低糖尿小鼠血糖值,提高糖耐量并减轻其多食、多饮、多尿的症状。(2)低剂量组小鼠血清TC、TG含量较模型组有显著提高(P0.01或P0.05),肝脏SOD、CAT活性显著提高(P0.05),MDA含量明显降低。(3)低剂量黄毛草莓积雪草合剂效果优于二甲双胍,毒性实验显示锈毛草莓积雪草合剂实属无毒。该研究结果表明锈毛草莓积雪草合剂具有降血糖作用,同时能够降低糖尿病小鼠的血脂水平,其作用机制可能与提高肝脏抗氧化能力有关。     

虾青素对四氧嘧啶致糖尿病小鼠降血糖作用研究

为研究天然虾青素在四氧嘧啶致糖尿病小鼠体内的降血糖作用,将天然虾青素分为高、中、低3个剂量组给四氧嘧啶致糖尿病小鼠灌胃,以0．9％生理盐水为模型对照,以二甲双胍为阳性药物对照进行实验。结果表明：三个剂量的天然虾青素均能较好的降低四氧嘧啶致糖尿病小鼠的血糖水平,并能减缓糖尿病小鼠消瘦和多饮多食的症状,以高剂量组的效果最佳。进一步考察了高剂量的虾青素对正常小鼠的影响,发现其对正常小鼠血糖无显著影响。虾青素对四氧嘧啶致糖尿病小鼠具有明显的降血糖作用。     

Hypoglycemic Effect of a Hot-water Extract from Defatted Sesame (Sesamum indicum L.) Seed on the Blood Glucose Level in Genetically Diabetic KK-Ay Mice

Genetically diabetic (type II) KK-A^y mice, male and 5 weeks of age, were divided into one group of 12 mice that were fed on a basal (BAS) diet and three groups of 6 mice each that were fed on the test diets for 4 weeks. Each test diet contained 4.0% of the hot-water extract (HES) from defatted sesame (Sesamum indicum L.) seed, 1.4% of the water eluent fraction (WFH) of HES or 0.7% of the methanol eluent fraction (MFH) of HES from a glass column packed with HP-20 resin. At the end of the feeding period, the BAS group was divided into the MAL and MALH groups which were respectively force-fed with 1 ml per mouse of a 20% maltose solution in water with or without 4.0% HES. The plasma glucose concentration and amount of urinary excreted glucose were lower from the HES and MFH diets than from the BAS and WFH diets. The levels of plasma glucose and serum insulin were lower in the MALH group than in the MAL group. These results indicate that HES and MFH had a reductive effect on the plasma glucose concentration of KK-A^y mice, and this effect is suggested to have been caused by the delayed glucose absorption.     

石硖龙眼未成熟种子种胚的萌发及成苗的研究

以花后82～87 d的石硖龙眼(Dimocarpus longan Lour.‘Shixia’)未成熟果实在4℃贮藏24 h,研究种子与种胚的萌发与成苗情况。结果表明:河沙直播未成熟胚的最终成苗率达到80%,远高于离体培养未成熟种子的最终成苗率(12.63%～44.03%);虽然4℃的低温贮藏略为推迟了河沙直播未成熟胚的萌发时间,但对最终成苗率及幼苗生长的影响不大,这对龙眼杂交育种中未成熟种子种胚的挽救具有较好的应用价值。     

含水量对种子贮藏寿命的影响

建立以收集种子为主体的基因库乃是当今保护植物种质资源最为普遍且可靠易行的方式,在世界库存约 61 0 0 0 0 0份种质资源中,近 90 %是以种子形式保存于约 1 30 0个基因库中。低温贮藏仍是目前基因库中种子种质保存的主要方法。种子含水量和贮藏温度是影响种子在贮藏期间生活力和活力保持的关键因素。传统的经验认为控制温度比控制水分来得安全有效,因而趋向于向低温或超低温的贮藏方向发展。国际植物遗传资源研究所（ＩＰＧＲＩ）曾推荐 5%～ 6%的含水量和 - 1 8～- 2 0℃低温作为各国长期保存种子的理想条件。目前,世界各国都把更多的…     

Effect of Longan Seed Extract and BHT on Physical and Chemical Properties of Gelatin Based Film

Gelatin films developed from fish skin incorporated with longan seeds extract (LS) or butylated hydroxytoluene (BHT) at different concentrations were prepared and characterized. The film thickness was in the range of 35 to 37 μm, and the transparency was 3.24 to 3.36 for the films with and without the addition of LS or BHT (p?<?0.05). Significant increases in redness (a*) and yellowness (b*) values were observed when the concentration of LS increased (p?<?0.05). Water vapour permeability (WVP) slightly decreased when the concentration of LS increased, while no significant change was observed between the control and the BHT films (p?>?0.05). Tensile strength (TS) and elongation at break (EAB) were in the range of 48 to 53 MPa and 16 to 19 %, respectively. The highest (65.7 J/g) and lowest (38.7 J/g) transition enthalpy was found in the control and LS 500 ppm films, respectively. Slight differences in protein pattern were observed under SDS-PAGE between treatments of the film. These differences were also observed in the FTIR spectrum. Films incorporated with LS or BHT showed the preventive effect on lipid oxidation of soybean oil during 30 days of storage. At the level of 500 ppm, LS provided the highest efficacy for lipid oxidation retardation as evidenced by lower peroxide value (PV), and thiobarbituric acid reactive substances (TBARS) values (p?>?0.05). The addition of LS or BHT had an impact on the film properties derived from fish skin gelatin, especially when high levels were added.     

基于Matlab语言的杂交水稻品种的颜色特征

本研究组建了基于机器视觉的杂交水稻种子检测硬件软件系统,并利用Matlab语言平台提取了杂交水稻种子图像的R、G、B、H、S、V六个颜色特征参数,研究了六个参数与水稻的品种相关性,实验证明通过颜色识别杂交水稻品种具有可行性,此结果为杂交水稻种子的基于机器视觉的识别方法提供了参考价值．     

龙眼胚胎发育研究进展(综述)

总结20多年来龙眼胚胎发育的研究进展,提出该研究领域存在的问题,并展望今后的发展方向。