Constituents of the Endophytic Fungus Annulohypoxylon boveri var. microspora BCRC 34012

A new azaphilone metabolite with a new substitution pattern, named annulohypoxylin ( 1 ), together with twelve known compounds, were isolated from the BuOH‐soluble fraction of the 95% EtOH extract of long‐grain rice (Oryza sativa) fermented with the endophytic fungus Annulohypoxylon boveri var. microspora (BCRC 34012). Annulohypoxylin ( 1 ) contains a dihydrobenzofuran‐2,4‐dione backbone, 1‐hydroxyoctyl side chain, and one γ‐lactone ring. Its structure was determined on the basis of extensive 1D‐ and 2D‐NMR analyses in combination with HR‐ESI‐MS. The relative configuration of 1 was confirmed by NOESY experiment. Other known compounds were identified by comparing their spectral data with those in the literature. All known compounds were isolated from this species for the first time.     

Phomachalasins A-D, 26-oxa[16] and [15]cytochalasans produced by Phoma exigua var. exigua, a potential mycoherbicide for Cirsium arvense biocontrol

Phoma exigua var. exigua, a fungal pathogen isolated from Cirsium arvense and Sonchus arvensis, proposed as a biocontrol agent of this noxious perennial weeds, produces in liquid and solid cultures different phytotoxic metabolites with potential herbicidal activity. The phytotoxic cytochalasins B, F, Z2, and Z3 and deoxaphomin were previously identified together with p-hydroxybenzaldehyde. Using spectroscopic methods, four new cytochalasins, termed phomachalasins A-D, were isolated and characterized as three new closely related 26-oxa[16] and one new [15]cytochalasans. They belong to a new subgroup of cytochalasans bearing a 1,2,3,4,6,7-hexasubstituted bicycle[3.2.0]heptene joined to the macrocyclic ring. None of the four new metabolites showed phytotoxic or antimicrobial activity. The lack of both phytotoxic and antimicrobial activities showed by all phomachalasins A-D was probably due to the strong modification of both functionalities and conformational freedom of the macrocyclic ring caused by its junction with the bulky and quite rigid new bicycle, namely bicycle[3.2.0]heptene.     

Chromatographic Fingerprint Analysis of Semen Ziziphi spinosae by HPLC-DAD Method

Abstract

Reliable, reproducible and valid fingerprint analysis methods using high-performance liquid chromatography-photodiode array detection (HPLC-DAD) for characteristic bioactive flavonoids and saponins of Semen Ziziphi spinosae (SZS) were developed and validated. HPLC separation of the chemical constituents of SZS was performed on an YMC-PACK ODS-A RP-18 column and detected at 270 and 204 nm for flavonoids and saponins, respectively. A mobile phase consisted of acetonitrile and 0.1% phosphoric acid aqueous solution was used with linear gradient elution. Using spinosin and jujuboside B as the reference markers of flavonoids and saponins respectively, 9 common fingerprint peaks of flavonoids and 10 common fingerprint peaks of saponins were specified based on the fingerprint analysis of 10 batches of SZS from different regions in China. The fingerprint analysis methods developed are reliable, reproducible and valid, and might be used as a more convenient approach for the species identification and quality monitoring and assessment of SZS.     

基于多元统计分析的南方红豆杉幼林修枝技术

为优化南方红豆杉幼林修枝技术,以福建省13年生南方红豆杉为研究对象,分析修枝木的树高、胸径与修枝强度对修枝2年后的林木生长与干形形质的影响。采用主成分聚类分析方法,依据参试的31株南方红豆杉单木修枝后的生长及形质性状的综合得分值进行系统聚类,确定最优的修枝木类群,估算最优类群总体参数,实现目标树修枝精确且优化。结果表明:修枝对单株材积和形数的影响随着修枝时间推移而变大; 2年后修枝木的树高、胸径与修枝强度对修枝后的生长与干形形质有着显著影响,进行目标树选择与修枝强度优化十分必要。在99%置信区间内,南方红豆杉目标树合理的修枝强度(相对高)为0.272 9～0.319 1,目标树要求树高501.55～527.45 cm,胸径11.93～13.56 cm。     

青花菜抗坏血酸过氧化物酶基因BoAPX的克隆与表达分析

根据NCBI基因数据库提供的抗坏血酸过氧化物酶(Ascorbate Peroxidase,APX)基因序列设计简并引物,以青花菜(Brassica oleracea var.italica)叶片cDNA和DNA为材料进行PCR扩增,基因定名为BoAPX(Gen-Bank登录号:HQ871864).BoAPX的基因组全长为1 394bp,具7个内含子,编码区全长为753bp,编码250个氨基酸残基.序列分析结果表明,BoAPX的N端中没有信号肽序列,为胞质型APX,BoAPX与已知APX具有较高的同源性.RT-PCR结果表明,BoAPX的表达受霜霉菌(Hyaloperonospora parasitica)诱导,在96h时达最大值,说明BoAPX与霜霉菌抗性相关.以pBI121为植物表达载体,BoAPX为目的基因,成功构建了重组表达载体pBI121-BoAPX.     

Chemical evaluation of seeded fruit biomass of oil pumpkin (<Emphasis Type="Italic">Cucurbita pepo</Emphasis> L. var. <Emphasis Type="Italic">Styriaca</Emphasis>)

Oil pumpkin (Cucurbita pepo L. var. Styriaca) is an economically important horticultural plant cultivated for oil production. After harvesting seeds, the residual biomass has a limited application and is usually left in the field. An experimental study was performed to evaluate the chemical composition of the seeded fruit oil pumpkin biomass (OP) dried by solvent-exchange using ethanol. The sugar composition of polysaccharides obtained by sequential extraction with water and dilute alkali indicated the prevalence of pectic polysaccharides. Hemicelulloses were released in higher amounts in the alkaline step. The chemical composition of OP and its individual tissues (peel, flesh and hairy flesh) was investigated and compared to the corresponding preparations of standard pumpkin (SP, Cucurbita pepo L.). The content of components (on oven-dry basis), calculated from the analysis data of the individual tissues, was estimated for OP: 7.9 % ash, 7.6 % Klason lignin, 19.3 % pectin (as uronic acids), 34.1 % neutral carbohydrates, and 27.4 % α-cellulose and for SP: 6.4 % ash, 4.0 % Klason lignin, 20.9% pectin (as uronic acids), 38.1% neutral carbohydrates, and 29.2 % α-cellulose, respectively. The OP biomass showed a higher proportion of hemicelluloses.     

薏苡多糖的提取、分离与纯化工艺研究

目的：建立薏苡非种仁部位中多糖的提取、分离和纯化工艺．方法：利用正交设计优化薏苡多糖的提取工艺,用Sevag法和三氯乙酸法脱蛋白．结果：正交设计优选薏苡多糖的提取工艺为12倍量的水提取2次,每次1h;Sevag法和三氯乙酸法均能有效地除去多糖中的蛋白质．结论：本实验为薏苡多糖的提取分离的条件提供了参考,为薏苡的进一步开发研究提供依据．