不同产地麻疯树种仁的含油量及脱油种仁的佛波酯含量

选用国内4种不同产地的麻疯树种仁,对其含油量以及脱油后的佛波酯含量进行了研究.采用GB/T 5512-85粮食、油料检验粗脂肪测定法进行麻疯树种仁含油量的测定;脱油后种仁经二氯甲烷超声提取佛波酯,采用高效液相色谱(HPLC)对其含量进行检测.结果表明,小金河、攀枝花、仁里、片角乡麻疯树种仁的含油量分别为58.29%、60.84%、58.83%和56.12%,脱油后种仁中佛波酯含量分别为2.43 mg g-1、2.25 mg g-1h、2.03 mg g-1和1.21 mg g-1.不同产地的麻疯树种仁含油量均有差异,在深入开发麻疯树资源时,种仁含油量的高低可作为其选种依据之一.4种不同产地的麻疯树种仁脱油后的佛波酯含最均高于无毒麻疯树品种,要利用麻疯树的脱油种仁这一潜在饲料资源,对其进行进一步脱毒处理是必要的.图3表3参10     

金沙江干热河谷地区不同含油量麻疯树种子的差异性

根据金沙江干热河谷地区麻疯树种子的含油量,将麻疯树种子分为组Ⅰ(26%~30%)、组Ⅱ(30%~34%)、组Ⅲ(34%~38%)、组Ⅳ(38%~42%).该地区种子体积介于1.544~1.680 cm3之间;其中组Ⅱ的种子最大(1.680 cm3),组Ⅳ的种子最小(1.544 cm3).组Ⅱ种子的百粒重同样为最高(69.367 g),组Ⅲ的种子最轻(62.313 g).出仁率从低到高依次为:组Ⅰ(61.752%)<组Ⅲ(63.352%)<组Ⅱ(64.132%)<组Ⅳ(65.192%).百粒种子产油量从组Ⅰ到组Ⅳ逐渐升高(17.731~25.342 g).1H-NMR图谱分析发现,各组种子之间的脂肪酸组成无明显差异,而脂肪酸成分的含量存在显著差异.种子的发芽势、发芽率和发芽指数随含油量的增加而升高,种子的吸胀速率则相反.种子含油量与种子大小的相关性不显著,与种子质量、出仁率、种子产油量、脂肪酸组成、发芽势、发芽率、发芽指数和吸胀速率之间则都有着极显著的相关性.图3表4参30     

麻疯树脱油种仁的总生物碱:提取及酸性染料比色法含量测定

对不同产地麻疯树脱油种仁中的总生物碱进行提取,采用酸性染料比色法,以盐酸川芎嗪为对照品,于420 nm处测定总生物碱含量,并利用单因素法考察最佳提取条件.结果表明,盐酸川芎嗪在0.036～0.180 mg mL-1范围内线性关系良好(R2=0.999 9),平均加样回收率为98.19%,RSD为2.53%(N=6).7个不同产地麻疯树脱油种仁中总生物碱含量在3.817～4.467 mg g-1之间,其中四川攀枝花地区的总生物碱含量最高.该方法操作简便,准确可靠,重复性好,可作为麻疯树脱油种仁总生物碱的含量测定方法.     

麻疯树种仁油粕脱毒

为获得经冷榨脱油后麻疯树油粕最佳的脱毒方法,采用超声提取,运用四因素三水平正交实验,考察了脱毒温度、脱毒时间、脱毒次数以及脱油后种仁与乙醇料液比对脱毒效果的影响.结果显示,最佳的脱毒方法为料液比8:1,40℃,超声3次,每次20 min.该方法处理后麻疯树油粕中佛波酯含量为0.011 mg g-1.脱毒后的麻疯树油粕对小鼠的急性毒性实验显示,小鼠无死亡,体重增长正常,未出现中毒症状,初步表明脱毒方法有效.图2表3参9     

麻疯树叶绿ω3脂肪酸脱饱和酶基因的克隆和鉴定

根据几个已知的植物ω3脂肪酸脱胞和酶基因序列,利用RT-PCR和RACE技术从麻疯树中克隆了一条编码叶绿体ω3脂肪酸脱饱和酶的cDNA序列.对该序列的分析表明,该cDNA的编码区长1 368bp,编码一个长度为455个氨基酸的蛋白质,推测的蛋白质相对分子质量(Mr)大小为52.1×103.同源分析显示,推测的氨基酸序列与其他物叶绿体脂肪酸脱饱和酶具有很高的相似性.RT-PCR分析表明,该基因在麻疯树叶片中有着稳定的表达.此外,还通过酵母表达系统鉴定了该基因编码的酶的功能.对转基因酵母的脂肪酸组成分析发现,α亚麻酸在转基因酵母中积累.上述结果表明,该麻疯树cDNA编码了一个叶绿体ω3脂肪酸脱饱和酶.     

麻疯树种质资源遗传多样性的ISSR分析

采用ISSR分子标记技术对大戟科属麻疯树9个自然居群的遗传多样性水平和遗传结构进行了研究.用10个引物对9个居群共135个样品进行了扩增,共获得169条清晰的扩增位点,其中多态性位点164个.POPGENE分析结果表明,麻疯树居群具有丰富的遗传多样水平(多态百分率PPB=97.04%,Neis遗传多样性H=0.2357,Shannon信息指数I=0.3760).AMOVA分析表明,9个自然居群间遗传多样性出现了较大的遗传分化(Gst=0.5398)可能与其有限的基因流(Nm=0.4667)和遗传漂变有关;而居群内有限的遗传分化可能是由于麻疯树自交、近交占主导方式的繁育方式有关.并进行了麻疯树居群的聚类分析.图3表4参19     

麻疯树酰基载体蛋白的基因克隆、表达分析及原核表达

从麻疯树胚乳cDNA文库中筛选分离了一个编码酰基载体蛋白的cDNA序列,全长为806 bp,其开放读码框(ORF)长度为393 bp.编码130个氨基酸,该序列在GenBanl澄录号为EF179617,命名为JcACP.该基因编码的蛋白质相对分子质量(M)约为14.4×103,等电点为5.2,具有酰基载体蛋白的典型特征--含有4'-磷酸泛酰巯基乙胺辅基的结合位点.RT-PCR试验结果表明,该基因在麻疯树的叶、茎和种子中表达,以种子中的表达量最高,在根中不表达,种子萌发后其表达量随萌发进程递增,在96 h时表达量达到最高.结果表明,JcAcP在种子中的高度表达可能与种子萌发时的代谢活动有关.同时,将其在大肠杆菌中成功进行了原核表达.     

土壤水分状况对麻疯树幼苗光合作用、超微结构和生理特征的影响

在控制试验条件下通过盆栽试验设置3个土壤水分[分别为田间持水量(FC)的80%、50%和30%]处理,研究土壤水分状况对麻疯树幼苗光合作用、超微结构及生理特征的影响.结果表明:土壤含水量为80%FC时,麻疯树叶片净光合速率(Pn)、光合色素含量、稳定碳同位素比率(δ~(13)C)、N含量和水分利用效率(WUE)最低;丙二醛(MDA)和过氧化氢(H_2O_2)含量、气孔导度(gs)、胞间CO_2浓度(Ci)和蒸腾速率(Tr)最高;叶肉细胞超微结构显示,叶绿体内部形成较大的淀粉粒,挤压严重.土壤含水量为50%FC时,MDA和H_2O_2含量、gs、Ci和Tr显著地高于30%FC处理,而叶片N含量和δ~(13)C与30%FC处理无显著差异.土壤含水量为30%FC时,Pn、光合色素含量、叶片N含量和WUE最大,MDA和H_2O_2含量最低;叶绿体内部淀粉粒和嗜饿颗粒体积较小,内部结构清晰可见,叶绿体膜结构完整.考虑到麻疯树是主要以种子为经济价值的树种,结合四川攀西地区的土壤养分状况,土壤湿度应控制在田间持水量的30%～50%左右,此时麻疯树光合作用最强,叶片N含量最高,WUE最大,将更有利于其生长结实,而过多的土壤水分可能会导致其徒长.图4表1参28     

酶联免疫吸附法测定麻疯树核糖体失活蛋白

建立了一种检测麻疯树核糖体失活蛋白(Curcin)的简便、快速的酶联免疫吸附测定法(ELISA).ELISA条件优化试验结果显示:最佳条件为costar酶标板在紫外线下照射45 min后进行包被;抗原最适稀释度为1:640倍(2.5μg/mL);curcin抗血清最适稀释度为1:12 800倍;2%封闭用山羊血清封闭120 min;二抗最适稀释度为1:5 000倍.在此试验条件下检测curcin含量,得到回归方程y=31.722x+106.88,相关系数R2=0.993 3.Curcin浓度在0.08～11μg/mL之间,曲线呈良好的线性关系.本方法的最低检测限为0.08μg/mL.高、中、低3个浓度的添加回收率分别为95.56%、102.27%、98.40%,平均回收率为98.74%.板内和板间的平均变异系数分别为4.78%和6.71%.Curcin抗血清与2种大戟科同类蛋白均无交叉反应.利用本方法成功检测了麻疯树种仁及脱毒饼粕中的curcin含量.     

麻疯树小热激蛋白基因JcHSP15.9的原核表达及耐热胁迫

小热激蛋白(sHSPs)是植物在逆境条件下产生的一类具有分子伴侣活性的应激蛋白,本研究拟构建原核表达载体并表达具生物学活性的麻疯树小热激蛋白以进一步研究其功能及应用.从麻疯树胚乳cDNA文库中获得全长为652 bp的cDNA序列,包含一个426 bp的开放阅读框,编码分子量大小约为15 926.13的胞质Ⅰ型小热激蛋白,命名为JcHSP15.9.通过构建原核表达载体,得到BL21(DE3)plysS/pET32a-HSP重组菌株.用JcHSP15.9在大肠杆菌中的过量表达来研究它的耐热胁迫能力,发现在常温(37℃)下重组菌株与野生型菌株生长曲线基本相似,但在高温(50℃)下重组菌较对照组菌株存活率有了显著的提高,推测JcHSP15.9可能与麻疯树的耐热胁迫有关.通过镍亲和层析柱纯化得到纯度较高的JcHSP15.9蛋白,分子量大小与预期一致,蛋白条带单一清晰.     

Effective antibacterial and antioxidant properties of methanolic extract of Laurus nobilis seed oil

This study was carried out to determine the in vitro antimicrobial and antioxidant activities of the essential oil, seed oil, and methanolic extract of seed oil obtained from Laurus nobilis L. (Lauraceae). The methanolic extract of seed oil exhibited more effective antibacterial activity comparing to essential oil and seed oil, GC-MS analyses of the essential oil resulted in the identification of 25 compounds. 1.8-Cineol (44.72%), a-Terpinyl acetate (12.95%), Sabinene (12.82%) were the main components. The fatty acid composition was characterized with the high content of linoleic acid (40.79%) and lauric acid (38.08%). The 50% (IC50) inhibition activity of the essential oil on the free radical DPPH was determined as 94.655 mg ml(-1), whereas IC50 value of methanolic extract of seed oil was found unstable. In the case of the linoleic acid system, oxidation of linoleic acid was inhibited by essential oil and methanolic extract of seed oil, which showed 64.28 and 88.76% inhibition, respectively. The inhibition value of the methanolic extract of seed oil was quite close to the synthetic antioxidant BHT, 92.46% inhibition.     

麻疯树种子中佛波酯的提取及对菜青虫的杀虫活性

佛波酯是麻疯树种子中的主要毒性物质之一.麻疯树种子经乙醇浸提、液液萃取和柱层析,获得佛波酯富集物.以TPA为外标,通过高效液相色谱(HPLC)定量分析佛波酯的含量,同时检测其对菜青虫的毒杀和拒食活性.结果显示,富集物中佛波酯含量达到0.817 35 mg mg-1.佛波酯富集物对3龄菜青虫具有显著的毒杀和拒食活性:毒杀活性表现为胃毒作用,胃毒活性具有明显的剂量效应和时间效应,48、72、120 h的佛波酯半致死浓度(LC50)分别为73.86、16.99、5.26μg mL-1;24、48 h的非选择拒食中浓度(AFC50)分别为9.81、5.39μg mL-1.图3表3参24     

麻疯树RAPD分析的影响因素

麻病树（Jatropha curcas L.）是一种具有广泛潜在用途的植物，为获得有重复性的RAPD分析结果，以对麻疯树的遗传多样性进行研究，本文作者对影响RAPD扩增结果的多个因素，包括缓冲体系成分，Taq酶、引物、模板浓度，PCR循环数等进行了研究，确定了反应的最适条件范围。     

能源植物黄连木油脂及其脂肪酸含量的地理变化规律

为更好地开发利用生物柴油木本能源植物黄连木（Pistacia chinensis Bunge）,研究了其油脂及其脂肪酸质量分数的地理变化规律。结果表明,黄连木果实与种子油脂质量分数随着地理经度和纬度的增加而降低,果肉油脂质量分数随着地理经度的增加而升高,而其纬向变化不显著。黄连木油脂中的脂肪酸有棕榈酸（C16：0）、油酸（C18：1）、亚油酸（C18：2）、棕榈油酸（C16：1）、硬脂酸（C18：0）、亚麻酸（C18：3）、花生酸（C20：4）等7种,其碳链长度集中在C16～C18之间,非常适合用来生产生物柴油。棕榈酸质量分数随着地理经度和纬度的增加而升高;油酸质量分数随着地理纬度的增加而降低,而其经向变化不显著;亚油酸质量分数随着地理经度的增加而降低,随着地理纬度的增加而升高;棕榈油酸质量分数随着地理纬度的增加而升高,而其经向变化不显著;硬脂酸和亚麻酸质量分数随着地理经度和纬度的增加而降低;花生酸质量分数随着地理经度的增加而降低,而其纬向变化不显著。     

Clove bud oil: an efficient, economical and widely available oil for the inhibition of wheat seed germination

Pre-harvest sprouting refers to the precocious germination of the grain in the spike prior to harvest as a result of moist weather conditions at harvest time. From the agricultural viewpoint, it is necessary to impose an exogenous dormancy to wheat seeds in order to improve the resistance of seed to pre-harvest sprouting. In this regard, we found that clove bud essential oil is a strong inhibitor for wheat seed germination. The extract obtained from clove bud by supercritical fluid extraction using CO₂ as solvent minimized the number of extracts to two compounds, eugenol and eugenyl acetate. Eugenol, as the main constituent of the oil, was responsible for its strong inhibitory activity in wheat seeds. The aqueous solution of clove bud oil was submitted to germination assay at various concentrations from 50 to 400 mg/L. Complete inhibition of seed germination was recorded when the concentration was 400 mg/L. Roots and sprouts have similar sensitivity to inhibitory effect. In an empirical study, the synergistic cooperation of eugenol and eugenyl acetate from clove bud oil in the inhibition of seed germination was found to be a 1:1 ratio. The clove bud essential oil is widely available and will broaden the horizon of applications for natural and safe inhibitors in the fields.     

3株油脂化工废水降解菌的分离鉴定

本研究从油脂化工废水处理装置中分离到３ 株降解脂肪酸和脂肪胺的功能菌,所筛选菌株对油脂化工生产废水有较好降解能力,其中 Ｆ Ａ２ 菌株对 Ｃ１８ 烯酸和 Ｃ１８ 伯胺作用４８ ｈ 的降解率分别为８８ ．８ ％ 和８２ ．３ ％ ．３株细菌分别归类于葡萄球菌属（ Ｓｔａｐｈｙｌｏｃｏｃｃｕｓ） 和棒状菌群     

Soil vs. canopy seed storage and plant species coexistence in species-rich Australian shrublands

The fire-prone shrublands of southwestern Australia are renowned for their high plant species diversity and prominence of canopy seed storage (serotiny). We compared species richness, abundance, and life history attributes for soil and canopy seed banks in relation to extant vegetation among four sites with different substrate conditions and high species turnover (50-80%) to identify whether this unusual community-level organization of seed storage might contribute to maintenance of high species richness. Soil seed bank (SSB) densities were low to moderate (233-1435 seeds/m2) compared with densities for other Mediterranean-type vegetation and were lowest for sites with highest canopy seed bank (CSB) species richness and lowest nutrient availability, but not richness or abundance of resprouters. Annuals were infrequent in the lowest nutrient sites, but there was no evidence that small SSB size was due to low seed inputs or a trade-off between seed production/storage and seed size in response to low nutrient availability. Sorensen's similarity between SSB and extant vegetation was 26-43% but increased to 54-57% when the CSB was included, representing levels higher than reported for most other ecosystems. Resprouting species were well represented in both the SSB and CSB, and there was no evidence for lower seed production in resprouters than in non-sprouters overall. The SSB and CSB held no species in common and were characterized by markedly different seed dispersal attributes, with winged or small seeds in the CSB and seeds dispersed by ants, birds, and wind (though none with wings) in the SSB. There was no evidence of spatial differentiation in the distribution of seeds of SSB species between vegetated and open microsites that might facilitate species coexistence, but most woody non-sprouters showed aggregation at scales of 1-2 m, implying limited seed dispersal. High similarity between overall seed bank (SSB + CSB) and extant species composition, high number of resprouting species, and seed dispersal processes before (SSB) and after fire (CSB) leading to differential spatial aggregation of post-fire recruits from the two seed bank types may buffer species composition against rapid change and provide a mechanism for maintaining species coexistence at the local scale.     

Geographic variations in Helleborus foetidus elaiosome lipid composition: implications for dispersal by ants

Summary. Geographic variations in the correspondence between diaspore phenotypes and disperser behavior are thought to determine the evolution of plant-animal dispersal mutualisms. Helleborus foetidus is a widely distributed plant in Western Europe, which seeds bear a lipid rich elaiosome attracting ant dispersers. Laboratory cross-tests were conducted to check the correspondence between diaspore phenotypes and ant preference in two localities of the Iberian Peninsula, Caurel and Cazorla, separated by 750 km. Diaspores from Caurel were systematically preferred to those from Cazorla by Formica lugubris (the major disperser at Caurel), and Aphaenogatser iberica and Camponotus cruentatus (both major dispersers at Cazorla). Further bioassays conducted on A. iberica only showed that differences in elaiosome traits were sufficient to explain ant preference. Separation of the lipid fractions composing the elaiosome revealed that triglycerides, diglycerides and free fatty acids were all dominated by oleic acid. The elaiosomes from Caurel contained relatively more free oleic acid but were less concentrated in linoleyl-containing triglycerides, free palmitic acid and free linoleic acid than those from Cazorla. The three lipid fractions were attractive to ants but dummies soaked with the free fatty acids extracted from Caurel were preferred to those from Cazorla. Taken together, these results reinforce the idea that oleic acid is a major releaser of seed collection by ants and suggest that geographic variations in free fatty acid composition affect the probability of diaspore removal by ants which in turn potentially determine plant demography.