人心果乳汁的流变学特性

通过测定浓度、pH值、温度、剪切力变化等对人心果乳汁溶液粘度的影响及与黄原胶的协效性,对人心果乳汁溶液的流变学特性进行了研究.结果表明:随着浓度的升高,人心果乳汁粘度逐渐上升;酸在一定程度上能降低溶液粘度;温度和剪切力均能改变溶液的粘度;人心果乳汁与黄原胶溶液有一定的协效性,但其协效性较低.     

香椿化学成分的初步研究

采用系统预试法,对香棒化学成分进行了初步的定性检验。结果表明,香椿嫩叶、叶中含有黄酮、萜类、蒽醌、皂甙、鞣质、生物碱等重要药用成分;香椿种子内含有醛、酮、萜类、皂甙、甾体和挥发油等,而挥发油中含有单质硫、硫华。本文对香椿可能具有的药用功效和环保功效进行了探讨。     

紫椴花和果实化学成分及其地理变异

采集不同地点紫椴花和果实,通过系统预试验,检测出紫椴花及花蕾中含有较多的酚类、糖和甙类,还检测到黄酮类化合物、蛋白质、香豆素及强心甙等,在花蕾中还含有少量鞣质.紫椴果实中含有酚类、糖和甙类,还含有少量黄酮化合物、香豆素和鞣质.对不同纬度和海拔紫椴花和果实中可溶性糖、总酚和黄酮的含量进行分析,发现3类化学成分含量随纬度、海拔的变化存在一定的变化规律.除花中总酚含量差异不显著外,紫椴花和果实中其他化学成分含量随着纬度升高而降低,随着海拔升高而增高.紫椴花中可溶性糖含量明显高于果实,其他化学成分在花和果实中的含量接近.化学成分含量聚类分析与遗传距离聚类分析比较表明:化学成分含量变异在纬度上是不连续的,在海拔梯度上是连续的.     

人心果品种资源表型遗传多样性研究

根据20个形态特征对25个人心果品种(类型)资源进行聚类分析和主成份分析,研究其表型遗传多样性,并初步进行品种分类.结果表明:人心果品种资源遗传变异丰富,平均变异系数达到了25.6%,品种间遗传距离在1.11~10.94之间;系统聚类结果与品种地理来源有明显的联系,来自美国的13个品种大致聚为3类,国内的12个品种(类型)聚为2类;叶片形状、果实形状与大小、花器特征和嫩梢(叶)有无褐毛等性状反映了64.82%的表型信息.综合考虑这些性状信息,可以区分大部分人心果品种.     

广西细叶云南松松脂组分的GC/MS分析

采用GC/MS联合技术对取自广西乐业、隆林、西林3县的细叶云南松松脂化学成分进行了定量和定性分析。从细叶云南松松脂中分离出67种化学成分,鉴定了其中的23种主要成分,占总离子流的89.27%。其中,单萜类9种,占26.86%;倍半萜类4种,占7.22%;二萜类10种,占65.92%。与云南松(正种)、马尾松松脂进行比较,单萜和二萜类的主要化学成分组成相差不大,但含量有一定的差别,单萜含量与马尾松相近,二萜类含量与云南松(正种)相近,倍半萜的主要化学成分相差较大;β-蒎烯含量平均值达到3.65%,高β-蒎烯含量是细叶云南松松脂的遗传特征组分之一。     

不同类型黄皮果实香气成分和特征香气物质分析

为给黄皮资源的开发利用提供理论支持,以8种黄皮果实为试材,采用顶空固相微萃取-气相色谱-质谱联用技术,对其果实中的香气成分和特征香气物质进行了检测和分析。检测结果表明:从8个黄皮品系的果实中共检测出挥发性成分99种,主要含有单萜烯类、单萜类、倍半萜烯类、类倍半萜类、醇类、酯类、酮类、醛类和其他类物质,其中含量较高的分别为β-水芹烯、D-柠檬烯、石竹烯、α-水芹烯、α-金合欢烯、1H-3a,7-亚甲基薁等成分;8个品系黄皮果实中的香气成分,均以单萜烯类和倍半萜烯类物质为主,二者均占各品系黄皮果实香气成分总含量的80%以上。聚类分析结果显示:大鸡心黄皮单独为一类,其余品系聚为一类。对其香气值(OAV)的分析结果表明:8个品系黄皮果实中均含有β-金合欢烯、α-水芹烯、β-水芹烯、D-柠檬烯、2-辛酮、α-蒎烯和石竹烯等特征香气物质,且α-水芹烯、β-水芹烯、D-柠檬烯对各黄皮品系香气的贡献均较大;8个黄皮品系间果实的香气成分存在明显差异,其中大鸡心和其他品系间的差异最大;α-水芹烯对各黄皮品系中果实香气成分的贡献最大。     

生物柴油原料树种文冠果的化学成分与综合利用研究进展

生物柴油原料树种文冠果的叶片、枝干、果皮、种皮、种仁中化学成分丰富多样,除了含有细胞壁组分木质素、纤维素、半纤维素、果胶质以及储藏物质蛋白质、糖类、脂肪外,还含有甾体、萜类、香豆素、黄酮类、有机酸以及蒽醌等多类次生代谢产物,具有在食用、药用、饲用、化工、能源等多个领域的开发利用潜力。在对该树种化学成分和综合利用方面的研究进展进行总结分析的基础上,提出了目前存在的问题和需要进一步研发的建议。     

太白米化学成分初步研究

对假百合属植物太白米茎叶、大鳞茎、小鳞茎3部分做化学成分系统预试，显示含有生物碱、皂甙、强心甙、黄酮、酚性成分、挥发油、甾体及萜类、糖类、有机酸、氨基酸等物质，但各成分的含量在植物不同部位存在差异。     

我国人心果的品种资源、生产现状及发展对策

人心果是一种具有广泛用途的热带果树,具有十分重要的开发利用价值．调查结果表明,我国人心果资源主要分布于广西中南部、云南广东福建省南部及海南、台湾等地,可划分为3个大的栽培区域．栽培品种根据果实形状不同,可分为椭圆形果、圆形果和圆锥形果3大类．人心果资源稀少、良种缺乏,尚未形成规模化商业性栽培,加工利用亦未起步。针对目前现状,提出了引进并加快良种繁育、建立高水平科技示范园、开展分类研究及培育良种、开展果胶提取与加工技术研究的发展对策。     

Review on Chemical Constituents and Comprehensive Utilization of Xanthoceras sorbifolia, a Biodiesel Feedstock Tree

生物柴油原料树种文冠果的叶片、枝干、果皮、种皮、种仁中化学成分丰富多样,除了含有细胞壁组分木质素、纤维素、半纤维素、果胶质以及储藏物质蛋白质、糖类、脂肪外,还含有甾体、萜类、香豆素、黄酮类、有机酸以及蒽醌等多类次生代谢产物,具有在食用、药用、饲用、化工、能源等多个领域的开发利用潜力.在对该树种化学成分和综合利用方面的研究进展进行总结分析的基础上,提出了目前存在的问题和需要进一步研发的建议.     

沙棘籽的综合利用Ⅰ——沙棘籽油渣的化学成分研究

以甘肃省漳县产沙棘籽提油后的渣为原料对其所含化学成分进行了研究。实验结果表明，油渣中含有十多类化学成分，特别是含有丰富的蛋白质、糖类、可食纤维素、钾、镁、铬、硒和锰等人体必需的营养成分。说明沙棘籽中的大部分生物活性物质在提油之后仍遗留在油渣中。为了提高沙棘资源的利用率、增加沙棘籽的附加值，必须进一步深入研究沙棘籽油渣的化学成分及其提取工艺，开发这些成分的新用途，对沙棘籽实行综合利用。     

Host responses to natural infection by Cytonaema sp. in the aerial bark of Eucalyptus globulus

The chemical and anatomical host responses to natural fungal infection by Cytonaema sp. in the aerial bark of 3‐year‐old Eucalyptus globulus plantation trees were examined. The lesion margin (LM) of the canker‐infected bark was characterized by the formation of a layer of dark extractives visible to the naked eye. Chemical analysis of the LM by gas chromatography‐mass spectrometry (GC‐MS), high‐performance liquid chromatography (HPLC) with ultraviolet detection and HPLC‐MS using negative ion electrospray ionisation indicated the presence of a range of compounds including hydrolysable tannins, polymeric proanthocyanidins, flavonoid glycosides, formlyated phloroglucinol compounds and volatile terpenes. These compounds were either undetectable in healthy tissue or present at significantly lower concentrations than in the LM. The LM of the canker‐infected bark was morphologically distinct from healthy phloem, its characteristics varying depending on severity of canker infection. In superficial infections in which only the phloem was affected, the following LMs were observed: (i) a continuous wound periderm of multiple layers, or (ii) an incompletely differentiated and discontinuous wound periderm. In cases of severe canker infections in which the vascular cambium had been killed, the new phloem formed subsequently contained traumatic oil glands in addition to the responses observed for superficial canker infections. All LMs were characterized by the formation of new parenchyma cells that stained positive for the presence of polyphenols. The significance of the chemical and structural responses as defence mechanisms against fungi causing stem canker is discussed.     

The aromatic and polyphenolic composition of lemon verbena tea

The chemical composition of the largely used tea from lemon verbena, Aloysia triphylla, was investigated. The qualitative and quantitative composition of the main aromatic and polyphenolic constituents of tea made by infusion from leaves were examined. The results showed that the relative proportions of the active constituents differ from those of the original leaves. The tea contained a large amount of polyphenolic compounds (mean value 675 mg/l; extraction yield 65%) including verbascoside (400 mg/l) and luteolin 7-diglucuronide (100 mg/l). It contained also 42 mg/l of essential oil (extraction yield 51%) with much more citral (77% of the essential oil) than the original leaves (41%).     

New monoterpene glycosides from Paeonia lactiflora

Three new monoterpene glycosides named 4-O-methyl-paeoniflorin (1), isopaeoniflorin (2), and isobenzoylpaeoniflorin (3), together with two known monoterpene glycosides, paeoniflorin (4) and benzoylpaeoniflorin (5), were isolated from the roots of Paeonia lactiflora. Their structures were established on the basis of spectral and chemical evidence.     

Two new nortriterpenoid saponins from Salicornia bigelovii Torr. and their cytotoxic activity

Investigation of characteristic constituents of Salicornia bigelovii Torr. led to isolation of two new 30-nortriterpenoid glycosides, Bigelovii A (1), Bigelovii B (2), together with two known 30-nortriterpenoid glycosides 3-4 and three known oleanane-type triterpenoid glycosides 5-7. The structures of new compounds were elucidated by extensive 1D and 2D NMR, and MS spectroscopic analysis, and chemical evidences. All compounds were isolated for the first time from Chenopodiaceae. Thus compounds 1-4 were evaluated for their cytotoxicity and compouds 1, 3 showed moderate activity against four cell lines, HL-60 (promyelocytic leukemia), MCF-7 (breast carcinoma), HepG2 (liver carcinoma) and A549 (lung carcinoma), with IC(50) values of 6.18, 78.08, 13.64 and >100μM for 1; 31.87, >100, ~100, >100μM for 3, respectively.     

Plant growth regulation effects of triterpenoid saponins

 To investigate structure–activity relations between the sugar chain structures of triterpenoid saponins and their plant growth regulation effects, several monodesmosidic saponins with betulin as an aglycon were synthesized by chemical and enzymic reactions. Three triterpenoids (betulin, betulinic acid, oleanolic acid) and synthesized betulin glycosides were submitted to germination and growth regulation tests on alfalfa seeds. We concluded the following. Betulin had a slight growth inhibitory effect on alfalfa radicles. Betulin glycosides exhibited stronger effects than betulin, and betulin glycosides with two to four glucose residues as a sugar moiety had the greatest inhibitory activity. These characteristics of growth inhibitory effects were considerably different from those of phenolic compounds so far reported. Some betulin glycosides also showed a significant growth regulation effect on alfalfa hypocotyls. However, hypocotyl growth was less affected than radicle growth for all betulin glycosides. Among the triterpenoids, betulinic acid had stronger growth inhibitory effects on alfalfa radicles than betulin, suggesting the importance of the carboxyl group at the C-28 position for the inhibitory effects of lupane-type triterpenoids. On the other hand, no germination regulation effects on alfalfa seeds were observed for any of the betulin glycosides or triterpenoids examined. Received: October 9, 2001 / Accepted: February 15, 2002 Acknowledgments This work was supported in part by a research grant (Development of Highly Functional Materials by Structural Modification of Carbohydrates) from the Ministry of Agriculture, Forestry, and Fisheries of Japan. We thank Saori Kudo for her assistance in isolating compounds by chromatography. Correspondence to:S. Ohara     

鸡屎藤地上部分化学成分的初步研究

通过系统预试和单项预试，初步确定鸡尿藤地上部分含有酚类，有机酸，生物碱，氨基酸、多肽（或蛋白质）、糖、多糖（或甙类）、黄酮及其甙类、甾醇（或三萜）和挥发油等成分。     

樟树叶精油组成分析及抗氧化活性研究

采用气相色谱-质谱法对不同化学类型樟树叶精油组成进行分析,对比4种樟树叶精油的成分差异;采用DPPH、ABTS、FRAP法对樟树叶精油的体外抗氧化活性进行评价,并使用丁基羟基茴香(BHA)作为阳性对照。研究结果表明:4种类型樟树叶精油共检测出46种主要化学成分,其中,异樟叶精油检测出35种化学成分,主要成分异橙花叔醇为29.48%;芳樟叶精油检测出33种成分,主要成分芳樟醇为71.91%;脑樟叶精油检测出33种化学成分,主要成分樟脑为46.28%;油樟叶精油中共检测出33种化学成分,主要成分1,8-桉叶油素为30.31%。4种樟树叶精油均具有一定的抗氧化活性,且随着精油浓度增加抗氧化能力增强,但其抗氧化能力均低于BHA。其中,脑樟叶精油的DPPH自由基清除能力及Fe 3+还原能力最强,当质量浓度为8 g/L时,脑樟叶精油的DPPH自由基清除率为30.34%±1.25%,FRAP值为(1.44±0.13)mmol/L;而异樟叶精油的ABTS自由基清除能力最强,当质量浓度为8 g/L时,异樟叶精油的ABTS自由基清除率为14.93%±2.32%。     

Acylated flavonol glycosides from Epimedium elatum, a plant endemic to the Western Himalayas

Herba Epimedii is a well-known Botanical preparation used over long time in traditional Chinese medicine. The extracts and chemical constituents from Epimedium species are aphrodisiac as well as to treat many ailments. Chemical investigation of lonely species growing in Kashmir Himalaya Epimedium elatum was undertaken to evaluate its chemical profile. Two unusual substituted acylated flavonol glycosides named Elatoside A (1) and Elatoside B (2) have been isolated from the ethanolic extract of E. elatum along with 23 previously known ones (3-25). All isolates were evaluated for antimicrobial and PPAR-γ ligand binding activity, and some of them appeared to be modestly active.