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91.
Seeds of 57 species of the genus Trifolium have been studied for the occurrence and concentration of soyasapogenol B glycosides and flavonoids. It was shown that all tested species contained soyasaponin I and in some species astragaloside VIII and/or 22-O-glucoside and 22-O-diglucoside of soyasaponin I were also present. Total concentration of saponins ranged from trace amounts up to 10 mg/g(DM). It was suggested that soyasapogenol B glycosides could be recognized as chemotaxonomic character of Fabaceae family. All but three tested species contained flavonoids. The majority of species contained quercetin as a sole flavonoid or in the mixture with a number of unidentified flavonoid components. Concentration of quercetine in some species was at the level of about 3 mg/g(DM). This high quercetin concentration and soyasaponin occurrence makes the seeds of some Trifolium species a potential source of health beneficial phytochemicals, to be used in human nutrition.  相似文献   
92.
In vitro culture of cotyledonary node (cn)explants, decapitated and intact seedlings of four different AsiaticVigna species (germinated and subcultured in MS-B5 mediumwith 1.0 mgl–1 BA) resulted in axillaryshoot formation only from the epigeal V. radiata and thehypogeal but allotetraploid V. glabrescens. The hypogealspecies V. angularis and V. umbellatafailed to exhibit this response. Shoot decapitation invivopromoted similar response only in V. radiata, indicatingthat in vitro culture in BA-supplemented medium isrequiredby V. glabrescens to achieve the same response.Histological observations of the cn explants from 4-d-oldin-vitro-germinated seedlings at d 0(inoculation day), d 4 and d 8 (after inoculation) revealed the formation ofprimary axillary shoots (pas) in both V. radiata andV. glabrescens. Secondary axillary branching at the baseofthe pas was observed at 8 d. Further examination by scanningelectron microscope (SEM) confirmed the presence of shoot buds enveloped by atleast two leaf primordia in the explants at d 0 in all epigeal species namelyV. radiata, V. mungo and V.aconitifolia together with the hypogeal but allotetraploidV. glabrescens. Consistently, these structures were absentin V. angularis and V. umbellata.Present histological and SEM observations support the previous findings ofAvenido and Hattori (Plant Cell Tissue Organ Cult, 1999) that the induction ornon-induction of shoots directly from the nodes of invitro-cultured cn explants is a new marker corresponding to thegenomic grouping within the Asiatic Vigna species. Basedonhybridization studies, Dana (Breeding Methods for Improvement of Crops, 1980)designates AA, A1A1 and A1A1/- toall epigeal, hypogeal and the hypogeal but allotetraploid AsiaticVigna species, respectively. Moreover, these findingsproved that the differential in vitro regenerationresponse(i.e., response to BA) arises from inherent anatomical and developmentaldifferences, and is supportive of the genomic grouping within subgenusCeratotropis of the genus vigna.  相似文献   
93.
The holotype of the prosauropod dinosaur Blikanasaurus cromptoni n. gen. and n. sp., a partial hindlimb, is described from the lower Elliot Formation (= Red Beds) (upper Carnian or lower Norian; Upper Triassic) of Herschel district, Transkei, South Africa. The new prosauropod family Blikanasauridae is characterized by a hindlimb that is extremely stocky, especially the metatarsus, with the distal tarsals medially situated. Blikanasaurus was an early experiment in the direction of heavily-built, quadrupedal saurischians, but it was not on the evolutionary line that gave rise to the Sauropoda.  相似文献   
94.
95.
Nesterenkonia massiliensis sp. nov., strain NP1T, is the type strain of Nesterenkonia massiliensis sp. nov., a new species within the genus Nesterenkonia. This strain, whose genome is described here, was isolated from the feces of a 32-year-old French woman suffering from AIDS and living in Marseille. Nesterenkonia massiliensis is a Gram-positive aerobic coccus. Here, we describe the features of this bacterium, together with the complete genome sequencing and annotation. The 2,726,371 bp long genome (one chromosome but no plasmid) contains 2,663 protein-coding and 51 RNA genes, including 1 rRNA operon.  相似文献   
96.
We investigated long-term trends in brown macroalgal assemblages inhabiting shallow subtidal rocky bottoms under the influence of thermal effluent discharge from the Brazilian nuclear power plant (BNPP). Three operational periods based on the units of the BNPP were analysed: T0 = pre-operational, between the years 1980 and 1983; T1 = operational period of unit 1, between 1988 and 1999; and T2 = operational period of units 1 and 2, between 2005 and 2012. Using generalized linear mixed models (GLMMs), we found significant declines in the numbers of genera and species over time. More than half of the species of brown macroalgae disappeared during T2. In addition, the numbers of macroalgal genera and species were inversely related to the local surface seawater temperatures. Multivariate analyses revealed a clear separation between the years of T2 and those of T0, indicating long-term changes in the community assemblages. Among the most common species in the area, the frequencies of Canistrocarpus cervicornis, Dictyopteris delicatula, Hincksia mitchelliae, Sargassum spp. and Sphacelaria tribuloides decreased during T2, while Padina gymnospora maintained rather high yearly frequencies during T2 (>40%). Our data suggest that seawater temperatures consistently higher than 30 °C together with peaks higher than 35 °C may have triggered the decline in the brown algae on rocky bottoms under the influence of the BNPP discharge. These results from southern Brazil are consistent with studies from other locations that ascribe changes in seaweed diversity to increasing seawater temperatures, highlighting the sensitivity of brown macroalgae to thermal stress and demonstrating their effectiveness as an ecological indicator for monitoring the effects of nuclear power plant effluents on coastal environments.  相似文献   
97.
任玉忠  周慧玲   《微生物学通报》1998,25(6):311-313
从我国四川省汉源县富泉矿马桑树根际分离到一株能分解钾的菌株,该菌细胞为杆状,近球状。有时具有分支状菌丝,成对V形排列。基丝有分隔,断裂成杆状或球状小体,革兰氏阳性,不运动,兼性厌氧。菌落由初级分支菌丝体组成,灰白色,无气生菌丝,细胞壁含有二氨基庚二酸LL-DAP(左旋),甘氨酸、天门冬氨酸、半乳糖、葡萄糖,无特征性糖;细胞壁组分属Ⅰ型。发酵葡萄糖产生乙酸和异成酸。用原子吸收法测定可溶性钾,比对照增加49.5%,证明能分解钾。DNA中G+C为63mol%。根据这些性状可归入蛛网菌属(Arachina<  相似文献   
98.
木霉属中国新记录种Trichoderma koningiopsis记述   总被引:1,自引:0,他引:1  
李广记  陈捷  刘铜  刘力行 《微生物学通报》2010,37(11):1663-1665
在华东地区木霉菌资源调查中,利用内转录间隔区(ITS)序列分析和形态学鉴定方法,对从土壤中分离到的木霉菌进行鉴定,发现一个中国新纪录种,即拟康宁木霉。Trichoderma koningiopsis/Hypocrea koningiopsis Samuels,C.SuarezH.C.Evans sp. nov.。该种典型的形态特征是在PDA以及CMD(玉米粉琼脂)上有瓶梗层出现象,而在MA(麦芽提取物)培养基上没有此特征。  相似文献   
99.
原核微生物的发现已有约340年,成千上万的原核微生物被发现和命名。近年来,随着分子生物学技术的发展,众多新的种属已经得到鉴定和命名,对这些微生物系统的总结并对中文命名系统适当调整已迫在眉睫。本文试图对人类发现最早、总量最多的350多属1 500多种杆菌和120多属1 200多种小杆菌进行总结和归纳,从生境、形态学(动静态、形状和尺寸)、生物化学、细菌和古菌属性等特征层次规范这类菌属的命名,期盼有助于推动国内外微生物分类学发展,有利于推动国际交流与合作。  相似文献   
100.
长盲蝽属(Dolichomiris Reuter)是盲蝽科(Miridae)中以吸食禾本科植物汁液为主的类群之一,多生活在海拔1000米以上的山地草原、草甸、草灌混生的草丛及森林草层之中。此属昆虫身体长形、瘦细,体背光滑或具很细微的刻点。唇基大且从上方可见,额扁平,向前延伸覆盖唇基基部或否。复眼接近或接触前胸背板。触角第1、2节(后者  相似文献   
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