柠檬醛对杨梅采后保鲜的作用研究

杨梅(Myrica rubra Sieb.Zucc.)是一种富含抗氧化物的健康水果,但极易腐烂变质,应用生物保鲜剂对杨梅保鲜具有无毒、经济和易推广等优点。本研究从自然腐烂的杨梅中分离纯化出7种腐烂病原菌菌株,其中Penicillium georgiense首次在杨梅采后病腐中被报道;在此基础上研究了柠檬醛对杨梅采后保鲜效果和对4种主要杨梅腐烂病原菌的抑菌机理。结果表明:用1.00%(体积分数)柠檬醛对杨梅进行熏蒸处理,可显著提高冷贮条件下杨梅的好果率;柠檬醛抑菌动力学研究表明0.10%(体积分数)柠檬醛可有效抑制4种病原菌孢子形成,从而抑制病原菌生长繁殖,以降低杨梅腐烂率。柠檬醛是一种有效的杨梅抑菌保鲜剂,它的应用将有利于杨梅采后保鲜,并可促进这一果树资源的开发利用。     

贵州省两种杨梅属植物资源的开发利用问题及对策

毛杨梅(Myrica esculenta Buch.Ham.)和矮杨梅(Myrica nana Chcral.)是杨梅科杨梅属(Myrica Linn.)木本植物,均为野生,在贵州省盘江流域较为常见。近几年来,随着栲胶工业产品结构的调整,混合及凝缩类栲胶需求增加,杨梅属植物树皮被采剥用作原料,且发展势头很猛,使资源急剧减少;多系砍树剥皮,植被难以恢复;果实、花叶利用较少,造成很大浪费。为改变这种状况,促进综合开发利用,笔者提出一些不成熟的建议供参考。     

杨梅果实提取物抗小鼠腹泻作用的研究

目的研究杨梅果实提取物的抗小鼠腹泻作用,包括预防和治疗作用。方法给小鼠腹腔注射甲型副伤寒沙门菌造成急性腹泻模型,经口灌胃杨梅果实提取物溶液,通过腹泻次数研究提取物对小鼠腹泻的预防作用;先灌胃杨梅果实提取物溶液再给小鼠注射菌液致泻,记录腹泻次数以研究提取物对小鼠腹泻的治疗作用。结果灌胃杨梅果实提取物的小鼠的腹泻次数均有明显的下降,且醇提物的作用效果要好于水提物。结论杨梅果实提取物对甲型副伤寒沙门菌引起的小鼠腹泻具有一定的预防和治疗作用。     

矮杨梅

杨梅是我国江南的著名水果,而同为杨梅科杨梅属植物的矮杨梅,知道的人恐伯就不多了。矮杨梅与杨梅在果实的大小、色泽上都很相似,但株高相差甚远,杨梅是高十几米的乔木,矮杨梅却是矮小的灌木。 矮杨梅(Myrica nana),又称云南杨梅。由于它的生长习性和形态特征,在产地又有爬地杨梅、矮脚杨梅、大果杨梅等俗称。     

荸荠种杨梅的疏果和落果功能性成分研究

对荸荠种杨梅的疏果和落果中主要功能性成分:总酚、黄酮类化合物、苹果酸、柠檬酸、总酸进行了测定。结果表明:疏果和落果之间的同一功能性成分含量存在显著性差异,且疏果中含量均高于落果。实验为荸荠种杨梅的疏果和落果的资源利用及应用开发提供一定的理论基础。     

环境友好型杨梅园高效栽培类型与综合效益评价

杨梅园实行精耕细作,会造成生物多样性下降、水土流失加重、杨梅病虫害加剧等不良后果。为克服或缓解这些难题,对杨梅林开展了不同类型的混交栽培模式和抚育方式的研究。结果表明:进行机械割草的杨梅园生物多样性较优,其维管束植物总计达78种,而以药剂除草的,总计仅11种,差异极显著;"杨梅针、阔、竹混交林+自然生草+机械割草"、"杨梅纯林+自然生草+机械割草"和"杨梅纯林+清耕(除草剂除草)"等三种栽培与抚育类型的主要病害有杨梅癌肿病等2种,主要虫害有白蚁类、袋蛾类、栗黄枯叶蛾等7种(类),均以针、阔、竹混交栽培模式受害最轻。对"杨梅+蓝莓"、"杨梅+蕨类(种植)"和杨梅自然生草等3种栽培模式以及机械割草、人工割草和药剂除草等3种抚育方式的"三大效益"进行了综合评价。     

大棚内地温和光照强度对荸荠种杨梅果实品质的影响

以荸荠种杨梅为实验材料,研究大棚内地温和光照强度对其果实品质的影响。通过监测杨梅大棚内外不同梯度地温和等一高度的光照强度,并多次抽取杨梅样品进行检测,结果表明,杨梅大棚对其内的地温具有明显的增温效应。在杨梅大棚深度5~20 cm范围内,越到土壤表面增温越快、增温效果越明显,增温总量越大;而越靠近地表越容易受气温和光照强度的影响,地温变化越大,随着深度增加影响较弱,变化趋缓。棚外气温和棚内地温之间是正相关的。杨梅大棚内光照最大值出现在晴天中午,因此为了增强棚内的光照和通风,晴天中午在保温的范围内尽量开天窗。成熟期大棚内比棚外的杨梅品质优良,但成熟期棚内的杨梅果实光泽没有棚外好,主要是由于转色至成熟期间棚内的光照不足引起的,需要人工补光,提高综合品质。     

杨梅安全优质高效栽培技术分析

杨梅是我国的一种重要果树类型,具有着色香味俱全的特点,非常受到人们的喜爱。在本文中,将就杨梅安全优质高效栽培技术进行一定的研究与分析。     

杨梅果实不同溶剂提取物抑菌特性的研究

目的探讨4种溶剂杨梅果实提取物对14种致病菌的抑菌作用,并对其中活性成分的含量进行测定和比较。方法利用常压浸提法制备杨梅果实的水、乙醇、乙酸乙酯和丙酮提取物;采用管碟法、琼脂平板稀释法测定各种杨梅提取物的抑菌活性,采用常规含量测定方法对各提取物中的主要成分及含量进行研究。结果4种杨梅果实提取物对革兰阴性和阳性菌均表现出了较强的抑菌活性,其中水提取物的抑菌活性最强。含量测定结果表明4种提取物的主要成分中总酚、黄酮含量以及总酸度相差较大,单宁含量差异较小。结论推测提取物中的主要抑菌成分为单宁类物质并确定杨梅果实的最佳提取溶剂为水。     

杨梅的冷藏保鲜法

杨梅原产于我国,分布于长江以南各省区,其中以浙江省的杨梅产量较高,品质较好。在杨梅成熟期正值水果淡季的初夏,因其果色鲜艳,汁液丰富、酸甜适度,深受消费者的青睐。由于在常温的２—３天后,杨梅果实就出现脱水裂口汁液溶出,并产生霉变现象,因此杨梅只适作为鲜销或作加工原料,而不耐贮藏。在生产上,如果利用冷藏的方法,并结合配套的贮藏技术,则可延长杨梅的贮运时间。一、杨梅果实的生物学特性杨梅果实为核果球形,其食用部分为密生的囊状体,肉质多汁。在运输过程中,由于振动而极易引起囊状体细胞的破裂,使汁液外流,果实…     

Anti-influenza virus activity of Myrica rubra leaf ethanol extract evaluated using Madino-Darby canine kidney (MDCK) cells

Myrica rubra leaf ethanol extract was added to culture medium of Madino-Darby canine kidney (MDCK) cells inoculated with influenza virus, and the inhibition of influenza virus replication was measured. Myrica rubra leaf ethanol extract showed anti-influenza virus activity irrespective of the hemagglutinin antigen type in the influenza virus type A (H1N1), its subtype (H3N2), and type B.     

Development of simple sequence repeat (SSR) markers from a genome survey of Chinese Bayberry (Myrica rubra)

ABSTRACT: BACKGROUND: Chinese bayberry (Myrica rubra Sieb. et Zucc.) is a subtropical evergreen tree originating in China. It has been cultivated in southern China for several thousand years, and annual production has reached 1.1 million tons. The taste and high level of health promoting characters identified in the fruit in recent years has stimulated its extension in China and introduction to Australia. A limited number of co-dominant markers have been developed and applied in genetic diversity and identity studies. Here we report, for the first time, a survey of whole genome shotgun data to develop a large number of simple sequence repeat (SSR) markers to analyse the genetic diversity of the common cultivated Chinese bayberry and the relationship with three other Myrica species. RESULTS: The whole genome shotgun survey of Chinese bayberry produced 9.01Gb of sequence data, about 26x coverage of the estimated genome size of 323 Mb. The genome sequences were highly heterozygous, but with little duplication. From the initial assembled scaffold covering 255 Mb sequence data, 28,602 SSRs ([greater than or equal to]5 repeats) were identified. Dinucleotide was the most common repeat motif with a frequency of 84.73%, followed by 13.78% trinucleotide, 1.34% tetranucleotide, 0.12% pentanucleotide and 0.04% hexanucleotide. From 600 primer pairs, 186 polymorphic SSRs were developed. Of these, 158 were used to screen 29 Chinese bayberry accessions and three other Myrica species: 91.14%, 89.87% and 46.84% SSRs could be used in Myrica adenophora, Myrica nana and Myrica cerifera, respectively. The UPGMA dendrogram tree showed that cultivated Myrica rubra is closely related to Myrica adenophora and Myrica nana, originating in southwest China, and very distantly related to Myrica cerifera, originating in America. These markers can be used in the construction of a linkage map and for genetic diversity studies in Myrica species. CONCLUSION: Myrica rubra has a small genome of about 323 Mb with a high level of heterozygosity. A large number of SSRs were identified, and 158 polymorphic SSR markers developed, 91% of which can be transferred to other Myrica species.     

杨梅根系和土壤微生物量碳、氮、磷生态化学计量随林龄的变化

利用空间代替时间的方法,研究了浙江省仙居县3、9、14、21年生根系和土壤微生物量碳(C)、氮(N)、磷(P)含量及化学计量比.结果表明,杨梅根系C、C:N在不同林龄间没有显著差异;随着林龄的增加,根系N、P含量降低,而C:P、N:P则增大;21年生杨梅根系N含量显著低于3年生(P<0.05),磷含量显著低于其他林龄(...     

HPLC法测定杨梅叶中杨梅苷的含量

目的:建立HPLC法测定杨梅叶中杨梅苷含量的方法。方法:采用Diamonsil C18(150 mm×4.6 mm,5μm)柱,流动相乙腈-0.1%磷酸水溶液梯度洗脱,流速1.0 mL/min,检测波长358 nm,柱温30℃。结果:杨梅苷在0.088-0.880 mg/mL内与峰面积呈良好线性关系,A=36113C-401.56,r=0.9994;平均回收率为102.4%,RSD=1.9%(n=9)。测得杨梅叶中杨梅苷含量为1.43%。结论:该测定方法准确,可靠,对于杨梅的进一步开发利用具有重要的参考意义。     

Population genetics of geographically restricted and widespread species of Myrica (Myricaceae)

Allozyme variation of 11 putative loci in five populations of the rare Myrica adenophora Hance, and four populations of its widespread congeneric species, M. rubra (Lour.) Sieb. & Zucc. was studied. Among the 21 alleles studied, no unique allele was detected for M. adenophora, whereas M. rubra had 3 alleles not found in the former species. In terms of genetic diversity, populations of the rare species contained fewer alleles per locus (1.5 versus 1.7), fewer effective number of alleles per locus (1.12 versus 1.20), fewer number of alleles per polymorphic locus (2.14 versus 2.46), lower percentage of polymorphic loci (30.9 versus 40.9), and lower expected heterozygosity (0.106 versus 0.163) than populations of the widespread species. Genetic distances within species average 0.043 for M. adenophora and 0.045 for M. rubra, and between species ranged from 0.052 to 0.177, with a mean of 0.103, which agrees with the very similar gross morphologies of these two species. Intrapopulation differentiation was similar in both species: G(ST) = 0.152 for M. adenophora, and 0.146 for M. rubra, whereas estimated gene flow based on G(ST) values were moderate in these two species (Nm = 1.39 versus 1.46). We inferred that M. rubra and M. adenophora are a progenitor-derivative species pair that emerged before migrating into Taiwan during the last glacial period. We consider the Hengchun population (Chiupeng, Hsuhai, and Chufengpi) and Taitung population (Tienkuan and Lanshan) of M. adenophora which probably arose from two subsets of the genome of M. rubra. Genetic drift was inferred to be one of the forces shaping the observed genetic structure in M. adenophora and M. rubra.     

Inhibitors of nitric oxide production from the bark of Myrica rubra: structures of new biphenyl type diarylheptanoid glycosides and taraxerane type triterpene

Three new biphenyl type diarylheptanoid glycosides, myricanol 11-O-beta-D-glucopyranoside, myricanone 5-O-beta-D-glucopyranoside, and neomyricanone 5-O-beta-D-glucopyranoside, and a new taraxerane type triterpene, myricetrione, were isolated from the bark of Chinese Myrica rubra. Their structures were elucidated on the basis of chemical and physicochemical evidence. Biphenyl type diarylheptanoids, triterpene, and their polyphenols showed potent inhibitory effects on nitric oxide production in lipopolysaccharide-activated macrophages. Furthermore, diarylheptanoids, myricanol and myricanone, were found to inhibit induction of inducible nitric oxide synthase.     

模拟酸雨胁迫对杨梅幼苗水分生理特性的影响

选择浙江省典型亚热带经济植物杨梅为对象,通过盆栽试验研究了重度酸雨(pH2.5)、中度酸雨(pH4.0)和对照(pH5.6)处理对杨梅幼苗水分生理特性的影响.结果表明:季节、年份和酸雨对杨梅幼苗的光合速率均有显著影响,各处理中,夏季的差异大于春、秋季,pH4.0处理对光合速率有促进作用;季节、年份、酸雨,季节-年份交互作用以及三者交互作用对气孔导度均有显著影响,各处理在夏季的差异大于春、秋季,酸雨对气孔导度有抑制作用;季节、年份、酸雨及季节-年份和季节-酸雨两两交互作用对蒸腾速率有显著影响,各处理夏季的差异大于春秋季,且pH2.5处理对蒸腾速率的抑制作用最强;酸雨、季节-年份和季节-酸雨交互作用对水分利用率有显著影响,且pH2.5处理对水分利用率有一定的促进作用.     

27味中药醇提物对酪氨酸酶体外活性的影响

以儿茶酚为底物,体外分光光度法研究了22个科的27味中药醇提物对酪氨酸酶的抑制活性。结果表明,在各种中药的50%乙醇(v/v)提取液中,生药质量浓度达到2 mg/mL时,红花(Carthamus tinctoriusL.)、杨梅叶(Myrica rubraS.)、黄芩(Scutellaria baicalensisG.)和绿茶(Camellia sinensisL.)相对L-抗坏血酸(维生素C)的酪氨酸酶抑制率分别达到128.62%、83.64%、79.65%和66.48%,它们在美白化妆品领域有潜在的应用价值。     

杨梅树皮黄酮的提取及体外抗氧化研究

采用乙醇热回流提取法对杨梅树皮中总黄酮进行提取,通过正交试验确定了杨梅树皮总黄酮乙醇热回流提取法的最佳工艺条件:以28目的杨梅树皮粉为原料,料液比为1∶60,用60%的乙醇溶液在60℃的水浴中提取2.5h,提取率达6.86%。利用清除DPPH自由基的能力和还原力作为指标测定了杨梅树皮总黄酮的抗氧化活性。结果表明,杨梅树皮黄酮有较强的抗氧化能力。     

Hydrogenase in actinorhizal root nodules and root nodule homogenates.

Hydrogenases were measured in intact actinorhizal root nodules and from disrupted nodules of Alnus glutinosa, Alnus rhombifolia, Alnus rubra, and Myrica pensylvanica. Whole nodules took up H2 in an O2-dependent reaction. Endophyte preparations oxidized H2 through the oxyhydrogen reaction, but rates were enhanced when hydrogen uptake was coupled to artificial electron acceptors. Oxygen inhibited artifical acceptor-dependent H2 uptake. The hydrogenase system from M. pensylvanica had a different pattern of coupling to various electron acceptors than the hydrogenase systems from the alders; only the bayberry system evolved H2 from reduced viologen dyes.