香荚兰酶促生香的研究

采用ＨＰＬＣ分析监测不同生香阶段和陈化期的香荚兰豆荚中香兰素等４个糖甙水解成分的含量变化。用β－葡糖甙酶处理香荚兰青荚,处理后之豆保,香兰素等４个糖甙水解成分的含量均远高于对照。对加酶量,酶促反应时间,反应温度,ｐＨ值４个关键因素进行条件筛选研究,并在所选最佳反应条件下,对不同生香阶段的豆荚进行酶处理。     

不同加工处理条件下香荚兰荚果中二种内源酶的活性变化

香荚兰(VanillaplanifoliaAndr.)成熟荚果经过不同的杀青与烘烤条件处理后,分析其内部的β-葡萄糖甙酶与过氧化物酶的活性的变化,结果表明:经不同的杀青温度与时间处理后,β-葡萄糖甙酶活性都比对照高,而过氧化物酶的活性较对照低;经过不同的烘烤时间与温度处理后,β-葡萄糖甙酶活性与过氧化物酶的活性都比未经任何处理的有显著性地增高。     

香荚兰豆提取物

随着香荚兰提取物愈来愈广泛地应用于医药工业和食品工业中,天然香料将成为香料工业的主流,这一事实已愈来愈清楚了。尽管天然香荚兰豆提取物的价格远远高于合成香兰素。香兰素集中体现了天然香荚兰夏与化学合成香兰素之间的明显差别。据分析,用化学方法制造的香兰素所含的香味成份只是天然香荚兰豆提取物的20％。香荚兰豆中含有200多种     

香荚兰成熟荚果中三种酶的活性测定

不同级别的香荚兰 (Vanillaplanifolia)成熟荚果以及其中的种子和肉质果壳中的 β -葡萄糖甙酶、过氧化物酶和多酚氧化酶的活性研究结果表明高等级的果荚中过氧化物酶活性高于低等级的果荚 ,种子中的 β -葡萄糖苷酶活性几乎达到肉质果荚的 2倍 ;过氧化物酶的活性主要分布在果壳中 ,没有在种子中测过氧化物酶的活性 ;多酚氧化酶的活性在测定样品极低 ,未能测出。     

吸附剂及培养基组成对香荚兰细胞悬浮培养产生香兰素的影响

本文报道了培养基的组成及添加吸附剂对香荚兰细胞悬浮培养产生香兰素的影响。结果表明,添加吸附剂活性炭及XAD-2后,香荚兰细胞产生的香兰素含量明显增加,而且活性炭的效果优于XAD-2;香荚兰细胞在全组成的MS培养基中香兰素含量均低于由矿物质盐组成培养基中的含量。可以考虑采用二步培养法来培养香荚兰细胞及产生香兰素。     

天麻及其活性成分药效作用的实验研究

天麻属兰科植物,从天麻中提炼出的化学成份有天麻素、天麻苷元、香荚兰醇、香荚兰醛、天麻醚苷、对羟基苯甲醛、柠檬酸、琥珀酸等[1]。其中活性成份含量最高的有效单体成份是天麻素(化学名为对羟甲基苯-β-D-吡喃葡萄糖苷,又称天麻苷)[2]。天麻素在非酶体系中稳定,在肝、肾、脑组织匀浆中天麻素可被代谢为天麻苷元。在组织中的代谢,以肾最快,脑次之,肝最小;在脑组织中,天麻素在小脑、丘脑、脑桥与延脑区域代谢速度快于皮层、纹状体和海马区[3]。有关天麻及其活性成分药效作用的实验研究较多,可见天麻有效成分的开发利用远无止境,但是某些作用机制尚有待深入研究和阐明,本文对有关研究文献综述如下。     

外源Me-JA 对菜用大豆荚采后衰老和腐烂的影响

研究了不同浓度茉莉酸甲酯 (Me JA)处理对菜用大豆荚贮藏期间衰老与腐烂的影响。结果表明 ,采用 1和 10 μmol/L浓度的Me JA处理可以降低豆荚呼吸强度、乙烯产生和O- ·2 的生成 ,保持荚中超氧化物歧化酶 (SOD)活性 ,减少荚内O- ·2 的积累 ,保持豆荚中Vc和叶绿素含量 ,并显著地提高豆荚中苯丙氨酸解氨酶(PAL)、过氧化物酶 (POD)活性和木质素的含量 ,减少腐烂的发生 ,从而延长贮藏期。但是 ,用 10 0 μmol/L的Me JA处理会促进豆荚衰老 ,增加腐烂的发生。     

芳香植物文摘

香兰素是香荚兰香气的最重要化学物质之一,它是在荚果熟化时由最接近的前驱体--香兰素葡萄糖苷生物合成的。香兰素葡萄糖苷在授粉后大约四个月的正在生长的豆荚里首先被检测出来,以后随着豆荚的成熟逐渐增加,直到豆荚完全成熟达到最高水平。     

香荚兰果荚的加工及生香机理(译编)

香荚兰为兰科(Orchidaceae)香荚兰属(Vanilla)肉质、多年生蔓性草本植物。体细胞染色体数2n=32(x=16)。原产于墨西哥、危地马拉、洪都拉斯和哥斯达黎加。 香荚兰属有110个种,其中有经济价值、为人类所利用的只有三个,即真香荚兰(Vanilla fragrans)、西印度香荚兰或瓜德罗普香荚兰(Vanilla pompona) (又叫大花香荚兰)和塔希提香荚兰(V. tahitensis),而以真香荚兰栽培面积最大,在商业上所占位置最为重要。 全世界年产成品香荚兰果荚1000—1600吨,生产的国家或地区有:马达加斯加、科摩罗群岛、印度尼西亚、留尼汪岛、墨西哥、波里尼西亚、瓜德罗普岛、塔希提、马来     

香荚兰果荚加工工艺最佳条件选择

香荚兰[Vanilla fragrans(Salisb。)Ames(V. planifolia Andr.)],是以生香为目的的热带栽培植物,其特有的香气是在加工过程中产生的。只有经过一番特殊的加工处理,方具有实用和经济价值。果荚加工方法得当与否,对产品的质量关系很大,直接影响到商品价格。国外对这方面的研究颇为重视。今后随着生产的发展,对其加工工艺的研究和最适条件的选择,在生产上和理论上都是十分必要的。     

The relation between glucovanillin, β-d-glucosidase activity and cellular compartmentation during the senescence, freezing and traditional curing of vanilla beans

The aim of this research was to improve our understanding of the mechanism of glucovanillin hydrolysis by β‐d ‐glucosidase activity in vanilla beans by studying their senescence, freezing and traditional curing. A batch of green pods from Madagascar was ripened at 30°C until fruits turned black; another batch was frozen for few days at ?18°C and defrosted at 35°C for 24 h and a third batch was cured using traditional methods. During treatments, samples were analysed for the yield of glucovanillin hydrolysis, and β‐glucosidase activity was measured. Cellular structures were also examined by light and transmission electron microscopy. Green fruits had a low yield of glucovanillin hydrolysis (<5%), a high level of β‐glucosidase activity (～1000 nkatal g^?1 fresh weight) and a perfect cellular integrity. Senescent fruits had a high yield of glucovanillin hydrolysis (>95%), no measurable β‐glucosidase activity and complete cellular degradation. Similar results were observed in beans after defrosting. During curing, beans had a medium yield of glucovanillin hydrolysis (<50%), no measurable β‐glucosidase activity and partial cellular degradation compared with senescent or defrosted beans. Results show that the mechanism of glucovanillin hydrolysis in vanilla beans is regulated by cellular compartmentation and that the β‐glucosidase activity level is not the limiting factor for complete hydrolysis. If total decompartmentation is obtained, then complete glucovanillin hydrolysis is observed even if most of the β‐glucosidase activity is lost. The β‐glucosidase activity level only has an effect on glucovanillin hydrolysis kinetics.     

Combined immobilized cell bioreactor and pulse column technology as a novel approach to food modification

The continuous use of an immobilized cell bioreactor (ICB) and a countercurrent pulse column is a unique approach to removing malic acid from coffee beans prior to roasting. This process recycled a high soluble solids water extract from the green coffee beans through a spiral-wound ICB loaded with food-grade bacteria (Lactobacillus spp. or Leuconostoc spp.) which metabolized malic acid in the green coffee bean extract. The demalated extract was then recirculated to extract the malic acid from the green beans during the countercurrent flow of the ‘malic acid-lean’ extract over the beans. The malic acid level in the beans was reduced by more than 80%. This extract recycle process may have other applications for removing unwanted organics or adding desirable water-soluble components. and is particularly suited to processing beans and grains.     

Localization of beta-D-glucosidase activity and glucovanillin in vanilla bean (Vanilla planifolia Andrews)

The morphology, anatomy and histology of mature green vanilla beans were examined by light and transmission electron microscopy. Beans have a triangular cross-section with a central cavity containing seeds. Each angle is lined with tubular cells, or papillae, while the cavity sides consist of placental laminae. The epicarp and endocarp are formed by one or two layers of very small cells, while the mesocarp contains large, highly vacuolarized cells, the cytoplasm being restricted to a thin layer along the cell walls. The radial distributions of glucovanillin and beta-glucosidase activity, measured on p-nitrophenyl-beta-glucopyranoside and glucovanillin, are superimposable and show how beta-glucosidase activity increases from the epicarp towards the placental zone, whereas glucovanillin is exclusively located in the placentae and papillae. Subcellular localization of beta-glucosidase activity was achieved by incubating sections of vanilla beans in a buffer containing 5-bromo-4-chloro-3-indolyl-beta-d-glucopyranoside as a substrate. Activity was observed in the cytoplasm (and/or the periplasm) of mesocarp and endocarp cells, with a more diffuse pattern observed in the papillae. A possible mechanism for the hydrolysis of glucovanillin and release of the aromatic aglycon vanillin involves the decompartmentation of cytoplasmic (and/or periplasmic) beta-glucosidase and vacuolar glucovanillin.     

Biotransformation of Externally Added Vanillin Related Compounds by Multiple Shoot Cultures of Vanilla planifolia L

The multiple shoots and callus cultures of Vanilla planifolia obtained from the nodal explant on MS medium supplemented with 6-benzylaminopurine (BAP) 2 mg l^?1 and α-naphthalene acetic acid (NAA) 2 mg l^?1 were maintained by regular subculturing every 30 days and also cultured liquid MS medium of the same hormonal combination. Shoots were transferred to the MS basal medium for rooting. Different explants along with vanilla pods and in vitro cultures were analyzed using HPLC for the presence of vanillin and related compounds. When the amount of these compounds was determined in explants and in in vitro cultures after precursor feeding and curing process, explants showed different profile after precursor feeding and after undergoing curing process. During further investigations we have applied a novel approach for curing in vitro tissues as done for vanilla beans. Curing of in vitro shoots resulted in a significant change in the aromatic compound profile.     

AccQ·Tag法测定绿豆蛋白酶解液中氨基酸含量

采用柱前衍生高效液相色谱法(AccQ·Tag法)同时测定17种氨基酸,氨基酸浓度在10～100μmol·L-1(胱氨酸浓度在5～50μmol·L-1)时,其峰面积和氨基酸浓度的线性相关系数均在0.99以上,17种氨基酸的加标回收率在92.1%～103.7%之间,用此法测定了绿豆蛋白酶解液氨基酸的含量,取得了满意的结果。     

Oligosaccharides in Five Different Vicia faba L. Cultivars

The oligosaccharide composition in seeds of some bean cultivars (two of Vicia faba L. and three of V. faba minor) have been examined. The sugars were isolated by solvent extraction and the concentrated extracts were analysed by PC and HPLC analyses. Characterization was also performed by thin-layer chromatography, enzymatic hydrolysis assays, GC determination of alditol acetate derivatives obtained after complete acid hydrolysis and FAB-MS of individual sucrose - galactosides. Although sucrose, raffinose, stachyose and verbascose were always identified, great differences in the total sugar content were found among the five cultivars. Sucrose and verbascose were the major components. Their contents were highest in the Muchamiel cv. (2.30 and 3.05 g/100g of dry bean, respectively). The selection of cultivars is the best way to improve the V. faba quality     

水杨酸诱导普通菜豆镰孢菌枯萎病抗病性的研究

普通菜豆是人类主要食用豆类之一,其营养价值高、栽培面积大。镰孢菌枯萎病是普通菜豆典型的土传病害,给普通菜豆生产带来严重损失。水杨酸(SA)被认为是诱导植物抗病反应的重要信号分子之一,参与植物的过敏反应(HR)和系统获得性抗性反应(SAR)。本研究通过不同植物激素处理普通菜豆BRB-130,结果表明,SA处理普通菜豆叶片使植株根中SA的含量升高,并显著提高植株对枯萎病原菌FOP-DM01菌株的抗性。SA诱导普通菜豆根组织中苯丙氨酸解氨酶、过氧化物酶活性及过氧化氢的含量显著升高,从而诱导普通菜豆产生HR和SAR。因此,SA作为普通菜豆抗病信号途径中重要的化学激活因子,能够显著提高普通菜豆对枯萎病原菌的抗病性,为发展环境友好型化学农药提供新的思路。     

A study of the glucosamine-containing constituents of the seeds of kidney beans (Phaseolus vulgaris)

1. The constituents of the seeds of kidney beans containing glucosamine that could be released by acid hydrolysis (0·5 n-hydrochloric acid at 100°) were extracted into the phenol-rich phase on partitioning between phenol and water at 70°. 2. These materials were also brought into solution on extracting the seeds with water (incomplete), or preferably with a slightly alkaline buffer in the absence of phenol. When these solutions were heated at 100° or treated with trichloroacetic acid, all the materials containing acid labile glucosamine were carried down with the precipitate. Treatment with pepsin rendered the materials containing glucosamine soluble again. 3. All proteins in these extracts of kidney bean were found to be associated with various amounts of neutral and amino sugars by high-voltage electrophoresis and chromatography on Sephadex G-200 columns. 4. The isolation and crystallization of the main sugar components, d-glucosamine and d-mannose, are described and their significance in plant glycoproteins is discussed.     

The role of cotyledon cell structure during in vitro digestion of starch in navy beans

Studies on the physico-chemical, microstructural characteristics and in vitro (under simulated gastric and small intestine conditions) starch digestibility of navy beans were carried out. The microstructure of raw and cooked beans observed through scanning electron microscopy (SEM) showed the presence of hexagonal or angular shaped cotyledon cells (50-100 μm size) containing starch granules with a size ranging between 10 and 50 μm. The extent of starch hydrolysis (%) after 120 min of in vitro gastro-intestinal digestion differed between whole navy beans (∼60%) and milled bean flour and bean starch (85-90%) after they were cooked under similar conditions. Starch hydrolysis (%) increased significantly when the cotyledon cells in the cooked whole navy beans were disrupted using high pressure treatment (French press). The storage of freshly cooked whole beans resulted in a lower (40-45%) starch hydrolysis whereas re-heating increased the same to 70-80% during in vitro small intestinal digestion. The SEM pictures of cooked navy bean digesta after different intervals of in vitro gastric and small intestinal digestion showed that the cotyledon cell structure is maintained well throughout the digestion period. However cotyledon cells appear shrunken and developed wrinkles during in vitro digestion. Particle size analysis of cooked bean paste taken before and after the in vitro gastro-intestinal digestion showed similar particle size distributions.