Volatile Components of Quince Fruit (Cydonia oblonga Mill.)

Steam distilled oil of quince fruit (Cydonia oblonga Mill.=C. vulgaris Pers., marmelo in Japanese) was analyzed by gas chromatography and gas chromatography-mass spectrometry. Sixty-two compounds, 2 hydrocarbons, 13 esters, 11 alcohols, 11 aldehydes, 11 ketones, 5 lactones and 9 miscellaneous compounds, were identified. Of them, the chemical structures of two new oxide compounds, trans- and cis-3-methyl-5-[(E)-3′-methyl-13′-butadien-1′-yl]tetrahydrofuran, were elucidated by instrumental analyses.     

Sterols and Triterpenoids from the Fruit of Cydonia oblonga Miller

An enzymatic method for glycolaldehyde production from ethylene glycol was investigated using immobilized alcohol oxidase and catalase. Those enzymes were immobilized onto Chitopearl BCW 3501. When only alcohol oxidase was immobilized onto it, the apparent activity was 190 units/g in wet gel using methanol as the substrate. Tris-HCl buffer (1.5 M; pH 9.0) was selected based on a high stability of glycolaldehyde and a low production of glyoxal as a by-product. Under the optimum conditions, 0.97 M glycolaldehyde was formed from 1.0 M ethylene glycol and the ratio of glyoxal to glycolaldehyde was less than 1%.     

新疆榅桲中的鞣质类化合物及其生物活性

榅桲是传统的中药之一,富含具有药用价值的化学成分,如鞣质类、有机酸、氨基酸、挥发油和黄酮等。鞣质类物质主要包括没食子酸鞣质、矢车菊苷配质、儿茶精、表儿茶精等,具有抗菌、抗病毒、抗突变、抗肿瘤、抗脂质过氧化、抑制酶活性,以及抗溃疡、止血、收敛、解毒等功效,对心脏和心血管也有一定的效应。     

Factors effecting adventitious shoot regeneration from leaf explants of quince (Cydonia oblonga)

A procedure for adventitious shoot regeneration from leaf explants of quince (Cydonia oblonga Mill.) using thidiazuron (TDZ) was developed. Excised leaves of cultures grown on Murashige and Skoog (MS) medium containing 5 M benzyladenine (BA) and 0.9% Gibco Phytagar were used. Several experiments were conducted to determine optimum concentrations of thidiazuron, -naphthaleneacetic acid (NAA) and sucrose. When the medium contained 1.5 M TDZ and 2.5 M NAA, 85% of the discs regenerated shoots with an average of eight shoots per leaf disc. An incubation period of three weeks in the dark was necessary for optimum shoot regeneration. Leaves excised from four to six-week-old cultures gave a higher percent shoot regeneration than leaves from cultures older than six weeks. Regeneration percentages were significantly reduced when sucrose concentration in the medium was less than 3%. A significantly higher percentage of shoots regenerated when leaf discs were placed on the regeneration medium abaxial side down as compared to the adaxial side.Regenerated shoots were cultured on MS medium containing 5 M BA and rooted on half-strength MS medium containing 10 M NAA. Rooted plantlets were acclimatized to greenhouse conditions for evaluation of any somaclonal variation. The importance of these findings are discussed in relation to in vitro improvement of plants.Abbreviations BA benzyladenine - MS Murashige & Skoog (1962) salt mixture - NAA -naphthaleneacetic acid - TDZ thidiazuron (N-phenyl-N'-1,2,3,-thiadiazol-5-ylurea) Approved for publication by the Director, West Virginia Agric. and For. Expt. Sta. as Scientific Article No.2346     

Isolation and Identification of 6-Methylsalcylic Acid and Gentisyl Alcohol from Phyllosticta sp.

Bovine serum albumin was reduced by incubating with various concentrations (0–200 mM) of 2-mercaptoethanol, and its emulsifying properties were examined for an oil-in-water emulsion system. A particle size analysis revealed that albumin reduced at 30 mM of the thiol yielded smaller oil particles than either native protein, or the protein reduced at 70 or 200 mM of the thiol. Furthermore, the particle size was almost constant during 35 days of storage with albumin reduced at 30 mM of the thiol, while an emulsion prepared using the native protein, or the protein reduced at 70 or 200 mM of the thiol was unstable during the same storage period. Gel filtration chromatography and transmission electron micrography show that serum albumin made aggregates with high molecular size by its disulfide reduction with 70 or 200 mM, but not with 30 mM of 2-mercaptoethanol. It was, therefore, concluded that the emulsifying property of serum albumin can be improved by a mild disufide reduction.     

Isolation and characterization of highly polymorphic microsatellites in tea (Camellia sinensis)

Relatively little is known about the diversity and origins of tea. The highest value tea products are sold on the basis of their region of origin but there are currently no methods available to verify the claims made on packages. We have developed 15 microsatellite loci for tea. These have been evaluated for polymorphism in a set of tea clones to determine their usefulness for authentication purposes. The majority of the microsatellites developed proved to be highly polymorphic both between and within different geographical origins and offer the potential to investigate the population genetics and genetic origins of tea.     

Relationship between calcium and agar on vitrification and shoot-tip necrosis of quince (Cydonia oblonga Mill.) shoots in vitro

Shoot-tip cultures of Quince C (Cydonia oblonga Mill.) initiated on Murashige & Skoog (MS) medium containing 5 M BA and 0.6% Phytagar showed both shoot-tip necrosis and severe vitrification. Culturing explants on medium containing 1.2% Phytagar and Ca levels of 3 mM (MS medium), 18 mM and 30 mM showed a decrease in growth with increasing medium Ca levels, being especially severe at 30 mM. The Ca content of the explants increased linearly with increasing medium Ca. Culturing explants on medium containing 3 mM, 9 mM, and 18 mM Ca at 0.6, 0.9, and 1.2% agar resulted in reduction in growth, shoot-tip necrosis, and vitrification when either factor was increased. The reduction in shoot-tip necrosis could be accounted for primarily by an increase in medium Ca levels but may also be affected by a change in explant growth. Increasing Ca concentration in the medium resulted in a linear increase in explant K, Ca, Mg, and B levels and a decrease in Mn and Na. Although increasing medium Ca or agar levels reduced vitrification, it is unclear whether they were the direct cause of the reduction in vitrification or whether this response was an effect of the reduction in culture fresh weight.Approved by publication by the Director, West Virginia Agriculture anf Forestry Experimental Station as Scientific Article No. 2199     

Purification and Characterization of a Lectin from Chinese Quince (Chaenomeles sinensis) Fruit

Chaenomeles sinensis lectin (CSL) was isolated from Chinese quince fruit by affinity chromatography. The molecular weight of native CSL was estimated to be 16 kD by gel filtration chromatography. This lectin was found to contain approximately 57% carbohydrates. The molecular weight of deglycosylated CSL was estimated to be 3.6 kD by tricine-SIDS-PAGE under reduced conditions. Our results suggest that CSL may be a homodimer. The hemagglutinating activity of CSL was inhibited by N-acetyllactosamine and chicken ovalbumin, and it was drastically decreased at pH levels of 9.0 or greater. CSL may be a useful tool for the purification of glycoconjugates.     

Isolation of a psychrotolerant Debaryomyces hansenii strain from fermented tea plant (Camellia sinensis) leaves

Abstract

A psychrotolerant, halotolerant and alkalophilic yeast was isolated from fermented leaves of Camellia sinensis Kuntze, the tea plant. The yeast strain, named Tea-Y1, was both phenotypically and genotypically identified as belonging to the species Debaryomyces hansenii. This assignment was confirmed by scanning and transmission electron microscopy. The analysis of growth curves demonstrated the ability this yeast strain to grow in a temperature range between 4°C and 28°C, with an optimum of 23°C. The ecology of this yeast in the C. sinensis phyllosphere, as well as its possible role in tea fermentation and storage, with particular reference to iced tea, are discussed.     

Incidence of aflatoxin producing strains and aflatoxin contamination in dry fruit slices of quinces (Cydonia oblonga Mill.) from the Indian State of Jammu and Kashmir

An investigation was undertaken to obtain data on the occurrence of aflatoxins and the aflatoxin producing potential of Aspergillus flavus strains isolated from dry fruit slices of quinces produced in jammu and Kashmir, India. A total of 147 A. flavus isolates recovered from dr fruit slices were grown in liquid rice flour medium and screened for the production of various aflatoxins by thin layer chromatography. The results showed that 23.14% of the tested isolates were aflatoxigenic, producing aflatoxins B₁and B₂ in varying amounts. Aflatoxins G₁ and G₂ were not detected. All 25 of the investigated market samples were also found to be aflatoxin B₁ positive and the level of contamination ranged from 96 to 8164 g/kg of the dry fruit which is quite high in comparison to the permissible level of 30 ppb. As per these results biochemical composition of dry fruit slices of quinces, along with climatic conditions seem to be very favourable for aflatoxin production by the toxigenic A. flavus strains. Therefore,monitoring of aflatoxins in dry fruit slices of quincesis recommended for this region.This revised version was published online in October 2005 with corrections to the Cover Date.     

Incidence of aflatoxin producing strains and aflatoxin contamination in dry fruit slices of quinces (Cydonia oblonga Mill.) from the Indian state of Jammu and Kashmir

An investigation was undertaken to obtain data on the occurrence of aflatoxins and the aflatoxin producing potential of Aspergillus flavus strains isolated from dry fruit slices of quinces produced in jammu and Kashmir, India. A total of 147 A. flavus isolates recovered from dr fruit slices were grown in liquid rice flour medium and screened for the production of various aflatoxins by thin layer chromatography. The results showed that 23.14% of the tested isolates were aflatoxigenic, producing aflatoxins B1 and B2 in varying amounts. Aflatoxins G1 and G2 were not detected. All 25 of the investigated market samples were also found to be aflatoxin B1 positive and the level of contamination ranged from 96 to 8164 micrograms/kg of the dry fruit which is quite high in comparison to the permissible level of 30 ppb. As per these results biochemical composition of dry fruit slices of quinces, along with climatic conditions seem to be very favourable for aflatoxin production by the toxigenic A. flavus strains. Therefore, monitoring of aflatoxins in dry fruit slices of quinces is recommended for this region.     

Isolation and Identification of Novel ADP-Ribosylated Proteins from Streptomyces coelicolor A3(2)

An important role of protein ADP-ribosylation in bacterial morphogenesis has been proposed (J. Bacteriol. 178, 3785-3790; 178, 4935-4941). To clarify the detail of ADP-ribosylation, we identified a new kind of target protein for ADP-ribosylation in Streptomyces coelicolor A3(2) grown to the late growth phase. All four proteins (MalE, BldKB, a periplasmic protein for binding branched-chain amino-acids, and a periplasmic solute binding protein) were functionally similar and participated in the regulation of transport of metabolites or nutrients through the membrane. ADP-ribosylation was likely to occur on a cysteine residue, because the modification group was removed by mercuric chloride treatment. The modification site may be the site of lipoprotein modification necessary for protein export. This report is the first suggesting that certain proteins involved in membrane transport can be ADP-ribosylated.     

一株仙人掌植物内生真菌的分离鉴定及活性研究

从元江仙人掌的茎中分离到一株产广谱、高活性抑菌物质的内生真菌,经测定对细菌、植物病原真菌和皮肤致病真菌共21种病原微生物有较为明显的抑制作用。形态特征表明,该菌株与曲霉属（Aspergillus）中的土生曲霉（Aspergillus terreus）的特征基本一致,18SrDNA序列分析显示本菌株与土生曲霉的同源性高于99％,但该菌株的分生孢子梗上有明显的瘤状突起,不同于模式菌株。因此认为该菌株为土生曲霉的一个变种,命名为土生曲霉云南变种（Aspergillus terreus vat．yunnanensis）。并对其活性物质的生产条件进行了初步摸索,确定用查氏培养基为最佳种子培养基,PDA培养基为最佳发酵培养基,4d为最适发酵时间。     

1株白木香内生真菌中抗肿瘤活性成分的分离纯化和结构鉴定

采用活性追踪的方法对白木香内生真菌螺旋木霉Trichoderma spiraleA17的抗肿瘤活性代谢产物进行了分离纯化和结构鉴定。通过凝胶柱层析和反相硅胶柱层析,从其发酵液的活性组分中分离到2个无色针晶化合物,质谱和核磁共振的鉴定结果表明化合物1是一个八氢萘衍生物,命名为木霉酸(Trichodermic acid),化合物2是酪醇(Tyrosol)。活性实验显示化合物1对SF-268、MCF-7和NCI-H460 3种肿瘤细胞株都具有显著的增殖抑制活性,而化合物2对这3种肿瘤细胞株只有微弱的增殖抑制活性。     

Isolation, structure elucidation, and antioxidant evaluation of cydonioside A, an unusual terpenoid from the fruits of Cydonia vulgaris

A novel terpenoid, cydonioside A (1), was isolated from the fruits of Cydonia vulgaris Pers. Its structure and relative configuration were elucidated on the basis of in-depth spectroscopic analyses, including 2D-NMR experiments as well as MM+ calculations. Compound 1 was assayed for its radical-scavenging activity towards the DPPH radical and the superoxide radical anion (O2*-), as well as for its overall antioxidant activity, as assessed by the formation of a phosphomolybdenum complex.     

普洱熟茶后发酵加工过程中曲霉菌的分离和鉴定

从云南省易武、基诺山、普洱和昆明后发酵加工生产的普洱熟茶堆中分离到7种曲霉菌,分别鉴定为：温特曲霉烟色变种,帚状曲霉,具黄曲霉,埃及曲霉,臭曲霉,日本曲霉原变种,以及局限灰曲霉。发现不同产地普洱熟茶中曲霉菌菌群的组成存在差异,对曲霉菌在普洱熟茶生产中的作用与意义进行了初步的讨论。     

Isolation of hopane triterpenes and other constituents from Machaerium brasiliense vogel (Fabaceae)

Phytochemical study of Machaerium brasiliense leaves extract afforded three hopane triterpenes 3,4-seco-21β-H-hop-22 (29)-en-3-oic acid (1), hopenone B (2), hopene B (3). In addition, lupeol (4), stigmasterol (5), β-sitosterol (6), daucosterol (7), uracil (8), allantoin (9) and trans-4-hydroxy-N-methylproline (10) were isolated. The structures of these compounds were established based on spectroscopic data in comparison to those described in literature. Considering the chemotaxonomic relevance of the isolated compounds, this is the first report of triterpenes 1, 2 and 3 in Fabaceae family and compounds 7, 8 and 9 in the genus Machaerium. Besides, preliminary screening on antiproliferative and antioxidant activities was performed for MBEB and its fractions.     

黄钩尺蛾在四个茶树无性系品种上的生长和存活(英文)

在实验室条件下, 对食叶害虫黄钩尺蛾Hyposidra infixaria Walker在4个茶树Camellia sinensis无性系品种（TV1, TV9, TV25和Teen ali 17）上的生长和存活进行了研究, 以确定其最适合寄生的茶树无性系品种。结果表明： 在TV25上的黄钩尺蛾幼虫期 (15.78 d)比在TV1 (18.14 d), TV9 (18.00 d)和Teen ali 17 (17.00 d)上显著缩短。黄钩尺蛾按幼期龄数分为5龄型和6龄型两类。6龄型幼虫在TV25上的发生率显著高于其在其他3个无性系品种上的发生率。在TV25上黄钩尺蛾幼虫和蛹的体重也显著高于在其他3个无性系品种上的。同样地, 以TV25为食的黄钩尺蛾未成熟阶段的存活率显著高于其以其他3个无性系品种为食的存活率。基于生长参数和存活率, 我们发现TV25是黄钩尺蛾最适合寄生的茶树无性系品种。