Importance of Cell Wall Degrading Enzymes Produced by Fusarium graminearum during Infection of Wheat Heads

Cytological studies were carried out to elucidate the importance of cell wall degrading enzymes (CWDE) during infection of wheat spikes by Fusarium graminearum. Scanning electron micrographs revealed that at 6–24 hours after inoculation (hai) of single spikelets with macroconidia of F. graminearum, the fungus germinated by forming several germ tubes and developed a dense hyphal network in the cavity of the spikelet. At 24–36hai, the fungus formed infection hyphae which invaded the ovary and inner surface of the lemma and palea. Transmission electron microscopical studies revealed that the fungus extended inter- and intracellularly in the ovary, lemma and rachis and caused considerable damage and alterations to the host cell walls. In different tissues of healthy and F. graminearum-infected wheat spikes the cell wall components cellulose, xylan and pectin were localized by means of enzyme-gold and immuno-gold labelling techniques. Localization of cellulose, xylan and pectin showed that host cell walls which were in direct contact with the pathogen surface had reduced gold labelling compared to considerable higher labelling densities of walls distant from the pathogen–host interface or in non-colonized tissues. The reduced gold labelling densities in the infected host cell walls indicate that these polysaccharide degrading enzymes might be important pathogenicity factors of F. graminearum during infection of wheat spikes. The results revealed that, infection and colonization of wheat spikes by F. graminearum and reactions of infected host tissue were similar to those reported for F. culmorum.     

人参中人参皂苷Ro和姜状三七皂苷R_1的含量测定

目的测定不同种类人参,人参不同部位中,红参加工过程中人参皂苷Ro(简称Ro)和姜状三七皂苷R1(简称R1)的含量含量。方法:采用HPLC的方法,对样品预处理及色谱条件进行优化。结果:鲜参中Ro和R1含量比红参中含量高;不同部位中Ro和R1的含量差异为:芦头参须主根;红参加工过程中的蒸制使Ro含量升高,R1含量降低。结论本文所建立的人参中人参皂苷Ro和姜状三七皂苷R1的含量测定方法准确、稳定可靠。     

咖啡湿法发酵中使用果胶酶对脱胶时间与杯品质量的影响

以云南阿拉比卡咖啡为原料,在咖啡湿法发酵环节中加入Pectinex Ultra SP-L果胶酶进行脱胶,并对加工出的咖啡豆进行理化及感官分析。结果表明：与自然发酵脱胶相比,果胶酶脱胶能缩短脱胶时间,有效快速脱除咖啡果胶。其脱胶时间与果胶酶的浓度、脱胶温度、鲜果成熟度呈正相关。与自然发酵脱胶相比,果胶酶脱胶所得咖啡豆的内含物质无显著差异,杯品质量干净稳定。就咖啡豆的杯品质量而言,0.01%果胶酶添加量脱胶处理要高于自然发酵脱胶,而添加量为1.00%、0.10%果胶酶脱胶处理略低于自然发酵脱胶。综上所述,果胶酶脱胶能保证咖啡品质的稳定性及提高咖啡加工效率,具有应用前景。     

人参/西洋参枯叶病缓解实验

通过各供试药剂在西洋参枯叶病上的使用,验证各供试药剂对西洋参枯叶病的缓解作用。结果表明,参多乐450倍液+益微450倍液对西洋参枯叶病缓解效果突出,在一定程度上解决了枯叶病给西洋参带来的危害。且该配方在人参上同样适用。     

活性炭在果胶提取液脱色中的应用研究

采用活性炭对果胶浸提液进行脱色,分别对活性炭添加量、吸附时间、吸附温度开展单因素试验,不考虑交互作用,以吸附率和果胶得率为衡量指标。结果表明,在活性炭添加量1%,吸附时间20 min,吸附温度60℃条件下,果胶提取液脱色效果最佳。     

Effects of AMF inoculation on growth of Panax ginseng C.A. Meyer seedlings and on soil structures in mycorrhizosphere

We aimed to investigate the effects of inoculating Panax ginseng C.A. Meyer seedlings with arbuscular mycorrhizal fungi (AMF) by examining the root colonization, plant nutrition uptake, growth characteristics, and soil aggregation of P. ginseng seedlings inoculated at the time of transplantation. At 16 weeks, the AMF spore density per 30 g of fresh mycorrhizosphere in seedlings inoculated with AMF (AMF+ seedlings) was 256.8 and that in seedlings not inoculated with AMF (AMF− seedlings) was 186.3, respectively. The colonization rate of AMF in the lateral roots of AMF+ seedlings was approximately 19% higher than that in the lateral roots of AMF− seedlings. The patterns of AMF colonization in ginseng roots were similar to those of the Paris-type mycorrhizal association. Plant growth characteristics, such as plant height, root length, leaf area, number of lateral roots, fresh weight of shoots and roots, and chlorophyll content, were significantly enhanced in AMF+ seedlings compared to AMF− seedlings. The macronutrient content (P, K, and Ca) and micronutrient content (Cu, Fe, and Zn) of both shoots and roots were also significantly higher in AMF+ seedlings compared to AMF− seedlings. Furthermore, glomalin content and soil aggregation were significantly enhanced in AMF inoculated areas. Our results indicate that AMF inoculation may enhance the growth of ginseng seedlings by improving the uptake of mineral nutrients and the soil structure in mycorrhizosphere.     

人参果胶的研究进展

人参是五加科人参属植物,主要生长在东亚,特别是寒冷地区,具大补元气,固脱生津,安神等作用。其主要成分有皂苷多糖、多肽、皂苷、氨基酸和维生素等[1,2]。目前,人参研究主要集中在调节中枢神经系统、促进大脑对能量物质的利用、改善心脏功能、降血糖、增强机体的免疫功能和抗癌作用等方面。因人参成分复杂,故进一步研究各成分所起功效成为了人参研究的重点方向。本文将对人参果胶分组成和研究现状做重点详细介绍,以便更好的开发利用人参中的果胶成分。     

生物质炭和果胶对再生水灌溉下玉米生长及养分、重金属迁移的影响

利用根箱试验方法比较了生物质炭和果胶对再生水灌溉下土壤—植物系统养分和重金属迁移特征的影响及差异性。结果表明,再生水灌溉不利于植物的生长,果胶和生物质炭两个处理相比,虽然植株生长无显著差异,但果胶处理植株的生长状况优于生物质炭处理;再生水灌溉时,果胶处理地上部生物量比对照增加了59.32%。与蒸馏水灌溉相比,再生水灌溉增加了根际土壤pH;灌溉水源相同时,果胶处理根际土壤pH略低于生物质炭处理。生物质炭和果胶都增加了土壤养分的含量,果胶对土壤碱解氮、有效磷和有机质的增加效果优于生物质炭,生物质炭对土壤有效钾的增加幅度大于果胶。生物质炭增加了植株的养分含量,果胶提高了养分的转运能力。生物质炭降低了土壤有效态Fe、Mn、Cu、Ni的含量,果胶增加了土壤有效态Fe、Mn、Cu、Pb、Ni的含量。果胶处理植株根系重金属含量普遍高于生物质炭处理,如蒸馏水灌溉下果胶处理根系Fe、Mn、Cu、Zn、Pb、Cd、Ni含量分别比生物质炭处理增加了165.29%,113.01%,21.16%,92.74%,14.61%,26.86%和53.43%,但Cu、Zn、Pb、Cd、Ni等元素在果胶处理的转运系数最低。该研究可为再生水灌溉下生物质炭和果胶在北方碱性土壤的农业安全利用提供理论依据。     

热处理对轻度加工葡萄细胞壁组分及相关酶活性的影响

以红地球葡萄为试材,研究了热水与热空气处理对轻度加工葡萄细胞壁水解酶活性的影响。结果表明,热处理可极显著地抑制轻度加工葡萄PG活性的上升,可显著地抑制贮藏后期（60～90天）PE活性;热处理轻度加工葡萄的硬度与PE活性呈显著负相关性,相关系数达到-0．7573,但与PG活性无相关性;轻度加工葡萄在贮藏过程中Cx活性缓慢上升,热处理显著地抑制了Cx活性的上升;热处理葡萄硬度的变化与Cx活性呈极显著负相关,相关系数r达到-0．9289;热处理对果胶含量的影响与对照比较差异不显著。     

果胶的咔唑硫酸分光光度测定法研究

对咔唑硫酸光度法测定果胶粉的水解产物──半乳糖醛酸的条件进行了研究。结果表明,在 ０．０３５～０.０４０ ｇ果胶粉中加入８～１２ｍＬ ０.５ ｍｏｌ／Ｌ的稀硫酸和１５ ｍＬ蒸馏水,当温度控制在 ６５～８０℃时,果胶粉在 １５～２０ ｍｉｎ内完全水解。水解产物半乳糖醛酸在浓硫酸介质中与咔唑形成稳定的紫红色络合物,λ｛ｍａｘ｝＝５４０ ｎｍ,显色时间为１．５ ｈ ３０ ｍｉｎ,ε'＝１．３８ｘ１０３Ｌ（ｍｏｌ·ｃｍ）。在０～１００ｍｇ／Ｌ浓度范围内与吸光度成线性关系,相对标准偏差＝１．３２％,回收率为９６％～１０７％,用于实际样的测定时,结果满意。