红毛丹果壳中齐墩果烷型三萜苷类成分的生防活性

研究了红毛丹果壳中的9个齐墩果烷型三萜苷类化合物对线虫(Panagrellus redivivus)、烟草青枯病菌(Ralstonia solanacearum)、棉花枯萎病菌(Fusarium oxysporum f.sp.vasinfectum)和香蕉枯萎病菌(Fusarium oxysporum f.sp.cubense)的生防活性,并分析了齐墩果烷型三萜苷拮抗病原菌的构效关系。研究结果表明,9个齐墩果烷型三萜苷对线虫(Panagrellus redivivus)均有一定的致死活性,部分化合物对烟草青枯病菌(Ralstonia solanacearum)、棉花枯萎病菌(Fusarium oxysporum f.sp.vasinfectum)和香蕉枯萎病菌(Fusarium oxysporum f.sp.cubense)显示拮抗作用,其中有4个齐墩果烷型三萜苷对这4种植物病原菌表现出兼抗活性。     

刺五加多向耐药性转运蛋白基因的克隆及其表达对皂苷含量的影响

利用简并引物进行聚合酶链式反应(PCR)扩增获得长度为693 bp的刺五加(Eleutherococcus senticosus)多向耐药性(pleiotropic drug resistance,PDR)转运蛋白基因,GenBank登录号为KC473536,其编码的231个氨基酸的蛋白属于PDR转运蛋白的核苷酸结合结构域。氨基酸序列与毛果杨(Populus trichocarpa)、蓖麻(Ricinus communis)和水稻(Oryza sativa)的PDR氨基酸序列一致性分别为8874%,9004%和8831%。RT PCR法检测PDR在刺五加不同生长发育时期和不同器官中表达情况和分光光度法测定刺五加总皂苷含量的结果显示: 刺五加PDR基因在整个生长期中均有表达,与皂苷在整个生长期中均有合成的特点相符,但两者的相关性未达显著水平。PDR基因在叶片和叶柄中高表达的特点与刺五加皂苷仅存在于叶中的特点相符,两者间存在显著的正相关关系(P<005)。     

Influence of tuber weight and cutting on growth and yield of safed musli (Chlorophytum borivilianum)

The present study was aimed to investigate the effect of different weight of planting material and cutting on safed musli cultivation. Tubers were divided into three weight categories (3, 6 and 9 g bulk^?1) and were either planted as whole or cut tubers. The plant growth and development were recorded at 60, 90 and 120 days after sprouting (DAS). The results showed that both factors had no interaction for all parameters measured. The sprouting percentage was not significantly different in all the treatments. The weight of planting materials used in the treatments had no influence on the overall plant growth and development. However, there was a significant difference observed between whole tuber and cut tuber treatments. At 90 DAS, tubers subjected to cutting encouraged the plants to produce the higher number of leaves (22.7) with improved total leaf area (642 cm²), fibrous root length (2795 cm) and tuber dry weight (7.8 g). The same pattern was observed at 120 DAS where the cut tubers produced the higher number of tubers (20.7) with increased length (8.6 cm) and diameter (6.6 mm). Consequently, these factors resulted in higher yield, 15.7 as compared to 13.6 g bulk^?1 in non-cut treatment.     

Effects of Alfalfa Saponins on In Vitro Physiological Activity of Soil and Rhizosphere Bacteria

Summary

In vitro effects of purified alfalfa (Medicago sativa L.) saponins (soyasaponin I, medicagenic acid [MA-3,28Na], MA-3glu, 28Na, and MA-3,28glu) on rhizosphere bacteria cell suspensions were investigated. Triphenyltetrazolium chloride (TTC)-dehydrogenase and fluorescein diacetate (FDA) hydrolytic activities were strongly inhibited (90-95%) by MA-3,28Na and MA-3glu,28Na in Bacillus thurin-giensis strains (HD-2 and UZ404). In Curtobacterium flacumafaciens (JM1011), TTC and FDA activities were reduced only by MA-3,28Na, while little or no effects were observed on the gram-negative strains Pseudomonas fluorescens (RA-2) and Agrobacterium tumefaciens (A-136). Soyasaponin I decreased FDA hydrolysis in HD-2 and JM1011, but increased FDA activity by 2-fold in RA-2. MA-3glu,28Na increased protein exudation or leakage by 5 to 10-fold in all strains, and MA increased leakage in all strains except RA-2. Soyasaponin increased protein leakage about 2-fold in JM1011, RA-2 and A-136, but reduced extracellular protein in HD-2 and UZ404. Results suggest that MA-3glu,28Na can deleteriously affect rhizobacteria, and in most cases, the aglycone (MA-3,28Na) is as biologically active as the sapo-nin MA-3glu,28Na.     

不同培养条件对金铁锁毛状根生长的影响

利用发根农杆菌ATCC15834诱导金铁锁获得毛状根,研究金铁锁毛状根的最优培养条件。结果表明,在5种培养基中,以在1/2MS培养基中皂苷的总产量最大;添加3%蔗糖、水解乳蛋白(LH)及IBA利于毛状根的生长及总皂苷的积累;而添加IAA、NAA、6-BA及蛋白胨抑制其生长。     

苜草素多糖、黄酮和皂苷对小鼠巨噬细胞RAW264.7β-防御素基因表达的影响

本研究旨在观察苜草素活性成分多糖、黄酮、皂苷对小鼠β-防御素表达的影响。分别采用含有30、60、90、150μg.mL-1苜草素多糖、含有10、20、30、50μg.mL-1苜草素黄酮、含有30、60、90、150μg.mL-1苜草素皂苷的细胞培养液处理RAW264.7细胞,观察其对小鼠RAW264.7细胞β-防御素(mouse beta-defensin,mBD)mRNA表达水平的影响。结果发现,苜草素多糖对mBD1的表达水平没有影响,对mBD2、mBD3的表达有促进作用,30μg.mL-1效果最明显;苜草素黄酮促进mBD1的表达,10μg.mL-1效果最明显,对mBD2、mBD3的表达有抑制作用;苜草素皂苷对mBD1的表达有促进作用,对mBD2的表达水平没有影响,对mBD3表达有抑制作用。苜草素中的多糖、黄酮、皂苷对RAW264.7细胞mBDs表达的作用效果不同,苜草素多糖可能主要促进动物的特异性免疫功能,苜草素黄酮、皂苷可能促进动物的先天性免疫功能。     

Effect of alfalfa (Medicago sativa L.) saponins on meat color and myoglobin reduction status in the longissimus thoracis muscle of growing lambs

The effect of alfalfa saponins (AS) supplementation on the meat quality especially the color for growing lamb was investigated. Fifty Hu male lambs with body weights (BW, 19.21 ± 0.45 kg) were divided into five groups and supplemented AS with 0, 500, 1,000, 2,000, and 4,000 mg/kg of dietary dry matter intake. After 90 days, all lambs were slaughtered. The longissimus thoracis muscle in lamb displayed significant changes in the content of intramuscular fat, especially n-3 polyunsaturated fatty acids, and drip loss within AS treatment (p < .05) between control and treatments groups. Redness (a*) significantly improved in both 0-day and 7-day storage with the AS supplementation coupled with the percentage of met-myoglobin reduction (p < .05). The redness (a*) change may result from improved met-myoglobin reducing activity, antioxidant enzymes, lactate dehydrogenase, and succinate dehydrogenase (p < .05) by AS supplementation in muscle. These enzymes may help to protect mitochondria function and reduce met-myoglobin, which bring a bright and red meat color.     

苜蓿皂苷对山羊瘤胃细菌发酵的影响

本试验旨在研究苜蓿皂苷对山羊瘤胃细菌发酵功能的影响。选择4只22月龄、体况良好、安装永久性瘤胃瘘管的徐淮山羊,晨饲后3 h采集瘤胃液,分离出细菌后,采用批次培养法进行体外发酵。试验分0%(对照组)、1%、2%及3%4个组,每组3个发酵瓶,每个发酵瓶为1个重复,体外厌氧培养24 h后,分别测定各处理组pH值、氨态氮浓度、微生物蛋白浓度及总挥发性脂肪酸含量。结果表明:添加1%~3%的苜蓿皂苷可以降低瘤胃细菌发酵液的pH值,提高总挥发性脂肪酸和氨态氮的浓度,但未对微生物蛋白浓度产生显著影响。     

Ruminal Metabolism in Sheep of Saponins from Yucca schidigera

Fifty-five mg per kg live weight of crystallized Yucca schidigera saponins, corresponding to 26 mg/kg live weight of sapogenins, was given daily intraruminally to two lambs for 11 consecutive days. Neither of the lambs showed any sign of toxicity throughout the experimental period. One lamb was killed 5 h after the last dose and GC-MS analysis of the free and conjugated sapogenin content samples of liver, and of the contents of the rumen, omasum, abomasum, duodenum, jejunum, ileum, colon and rectum, of faecal samples collected before dosing started, and of parts of the administered Yucca saponin were performed. The Yucca material contained mainly sarsasapogenin and smilagenin saponins. Ingested saponins were quickly hydrolysed in the rumen to free sapogenins and, in part, epimerized at C-3 to afford episapogenins. The absorption of free sapogenins appeared to occur in the jejunum. The metabolism of Yucca saponins was identical to that of Narthecium ossifragum saponins, and it is suggested that Yucca saponins could replace N. ossifragum saponins for toxicity studies on the latter plant.     

运用超声法提高皂荚皂甙浸出率的研究

应用超声技术对皂英皂甙的提取工艺进行了多因素的研究，得出提取皂荚皂甙的最佳工艺参数：浸泡水温为45℃，时间12h；超声频率1000kHz，时间30min，浸出率达24．50％。实验证明，该超声工艺比传统浸提工艺浸泡时间节省33％，节能20．1%，浸出率提高了4．1％，可以作为实验室和大规模生产的模拟工艺。