Effects of different drying methods on phenolic components and in vitro hypoglycemic activities of pulp extracts from two Chinese bayberry(Myrica rubra Sieb.et Zucc.)cultivars

The effects of two different drying methods,namely hot-air drying and freeze drying,on the phenolic profiles,antioxidant and hypoglycemic activities of pulp extracts from two main Chinese bayberry cultivars(’Biqi’or’BQ’and’Dongkui’or’DK’)were evaluated.The results showed that’BQ’bayberry provided higher total phenolic(TPC),total flavonoid(TFC)and total anthocyanin(TAC)contents than’DK’bayberry after the same drying method,while its antioxidant and hypoglycemic activities were highly affected by drying method.Freeze-dried samples possessed significantly higher TPC,TFC and TAC,and exhibited more potent antioxidant and hypoglycemic activities than hot-air dried ones(P<0.05).Freeze-dried’DK’bayberry exhibited similar antioxidant activities and a-amylase inhibitory activity,but higher a-glucosidase inhibition than freeze-dried’BQ’bayberry(P<0.05).Compared with hot-air dried samples,freeze-dried samples had significantly higher contents of cyanidin-3-O-glucoside,myricitin-3-O-rhamnoside,quercetin-3-O-galactoside,quercetin-3-O-glucoside and quercetin-3-O-rhamnoside,which had been proved to be the main contributors to the in vitro hypoglycemic activities of bayberry pulp extract.All these results demonstrate that freeze drying is more suitable for the preservation of phenolic components in the pulp extract of Chinese bayberry,and the pulp extract of freeze-dried’DK’could be applied as a potential hypoglycemic food additive.

Development of Antioxidant Packaging Film Based on Chinese Bayberry Tannin Extract and Polyvinyl Alcohol

The current work explores the potential use of commercial Chinese bayberry tannin(BT)to develop antioxidant PVA-based films using solvent casting process for packaging applications.The effect of BT concentration on opa-city,water resistance and antioxidant capacity of resulting films was investigated.Properties like tensile strength,thermal behavior,and morphological aspects were also characterized.The experimental results showed that PVA/BT films formed with uniformly brown color and generally good transparency,offering good antioxidant ability.The PVA film containing BT presented slightly higher water resistance according to the results of moisture content and water vapor permeability,especially at low BT content(<10 wt%).The PVA can be compounded with up to 10 wt%BT without any obvious deterioration in the tensile strength.The PVA/BT films exhibited better thermal degradation behavior compared with PVA alone because of the chemical bonds of PVA-BT and the for-mation of char at high temperature.Based on the results,PVA incorporated with Chinese bayberry tannin may provide broader formulation options for packaging materials with antioxidant action.

Assisted Compatibility, and Balanced Regulation of the Mechanical, Thermal, and Antioxidant Activity of Polyvinyl Alcohol-Chinese Bayberry Tannin Extract Films Using Different Di-Aldehydes as Cross-Linkers

Polyvinyl alcohol(PVA)-based films containing Chinese bayberry tannin(BT)were prepared by cross-linking using glyoxal,glutaraldehyde and dialdehyde starch,individually.The presence of cross-linkers was evident to promote the transparency and decrease the moisture content of PVA/BT films,while the water solubility stayed almost unchanged in the cross-linked PVA/BTfilms.All cross-linkers provided promotion of the water vapor per-meability,mechanical property and thermal stability of PVA/BT films.The best water vapor barrier capacity was found in case of glutaraldehyde cross-linked PVA/BT film,while the highest tensile strength was encountered in case of glyoxal cross-linked PVA/BT films,compared with the uncross-linked films.The scavenging action of the films towards DPPH radical activity was influenced by the nature of each cross-linker.Namely,the PVA/AT film cross-linked by glutaraldehyde acquired the lowest radical scavenging activity in a certain time,suggesting that glutaraldehyde decreased the release rate of BT from PVA.Based on the experimental data,glutaraldehyde and dialdehyde starch could be more suitable for PVA/BT film preparation since they can promote the intermo-lecular interaction of PVA and BT to a reasonable extent.

SSR Marker Technique and Its Application on Chinese Bayberry( Myrica rubra,Myricaceae)

SSR marker technique was summarized from the aspects of types and genetic characteristics of SSR loci, principles and characteristics of SSR technique, and development of SSR markers. The literatures about the applications of SSR markers on germplasm studies of Chinese bayberry were reviewed to provide a refer- ence for related studies.

响应面法优化沙棘杨梅复合果汁

沙棘酸涩,采用杨梅复配技术可改善感官,形成一款消费者喜爱的复合果汁。以沙棘原浆和杨梅汁为主要原料,白砂糖等为辅料,通过单因素和响应面分析试验确定沙棘杨梅复合果汁的最佳原辅料配比。并在此基础上,选取低酯果胶、高酯果胶、黄原胶、卡拉胶、魔芋胶和柚皮果胶为复合果汁稳定剂,通过单因素和响应面分析试验确定稳定剂最佳配比。结果表明:沙棘杨梅复合果汁的最佳原料复配比为沙棘原浆∶糖∶杨梅汁质量比=30∶15∶31.113,此时感官分最高为34.83,总酚质量浓度为432.66 mg/L,DPPH(2,2-联苯基-1-苦基肼基)自由基清除率为39.29%。沙棘杨梅复合果汁稳定剂最佳配比为低酯果胶0.15%、魔芋胶0.095%、柚皮果胶0.093%。杨梅汁复配可以提高沙棘汁感官特性,经响应面优化复配的果汁具有沙棘和杨梅独特的香气,色泽呈橘黄色,组织状态均匀,口感酸甜适口。

不同免疫诱导剂对杨梅凋萎病抗性的影响

以东魁幼苗为试材,研究3种诱导剂(枯草芽孢杆菌、水杨酸、芸苔赤霉酸)对杨梅凋萎病抗性及生长发育的影响。结果表明,在枯草芽孢杆菌和芸苔赤霉酸处理下,杨梅凋萎病病情指数显著低于对照组,相对诱导效果分别为35.44%、27.16%;在枯草芽孢杆菌、芸苔赤霉酸诱导处理下,叶长、叶面积均高于对照,叶面积较对照分别提高8.82%、8.42%;3种诱导剂处理下,叶绿素含量均有不同程度增加,在枯草芽孢杆菌处理下叶绿素a、叶绿素b含量均显著高于对照;超氧化物歧化酶、过氧化物酶、过氧化氢酶等抗氧化酶活性在3种诱导剂处理下,均有显著提高,其中枯草芽孢杆菌、芸苔赤霉酸的作用较为显著,且其对应丙二醛含量显著低于对照。综上,研究筛选到能诱导杨梅凋萎病抗性的2种诱导剂,即枯草芽孢杆菌和芸苔赤霉酸,可为今后杨梅凋萎病的防控及相关研究提供重要依据。

东魁杨梅高温干旱调查与防御对策研究

2022年6—8月浙江省台州市黄岩区出现了连续高温干旱天气,多项高温、干旱指标超过历史记录,对黄岩东魁杨梅造成严重伤害。为了解高温热害、干旱对东魁杨梅的影响原因和为害规律,对黄岩杨梅的主要产区和典型基地进行了调查分析。结果表明,当年东魁杨梅受害率达73%,灾情指数达21.4。高温热害影响范围广,叠加干旱后影响严重,死亡率达1.9%,还有3.6%树势遭受严重影响,次年无法形成产量。其次,热害干旱强烈抑制了东魁杨梅的夏梢抽发。研究认为,微环境对旱情造成了一定的影响,对以后杨梅靶向抗旱提供了一定参考价值。另外,针对灾情提出了高温抗旱管理的若干对策措施,为来年健树壮果奠定基础。

早熟杨梅新品种甬早梅2号的选育

甬早梅2号是从荸荠种杨梅种植区发现的优良变异单株选育而成的杨梅早熟新品种,完全成熟时果面呈乌紫色,肉柱圆钝,平均单果质量12.76 g,可食率92.83%;可溶性固性物含量(w,后同)12.20%,可滴定酸含量1.09%,柠檬酸含量1.04%,维生素C含量89.56μg·g^(-1),果实风味酸甜。树势中庸,分枝密度较稀,树冠透风透光性好;叶色深绿,叶片倒披针形、先端为渐尖形,叶缘全缘无缺刻;以中、短果枝结果为主,结果均匀,成熟后果柄与果实难分离,大小年结果现象不明显。早熟性好,在浙江宁波地区6月7日果实成熟,比荸荠种提早5~7 d。

Physiological and molecular characteristics of two ploidy mutants in Myrica rubracv.Dongkui

In this study, two ploidy mutant lines ofMyrica rubra cv. Dongkui （DK） were identiifed and named as DB1 and DB2. The lforal organ, leaf cel structure, ploidy, and number of chromosomes of the two mutants were investigated. Meanwhile, anthocyanin contents at different developmental stages were analyzed, and the Cy-3-glu contents of DB1 and DB2 at the ful ripe stages are signiifcantly higher than that of DK by 27.84 and 23.51%, respectively. Furthermore, 6 RNA libraries at two developmental stages （young fruit stage and ful ripe stage） were built for RNA-Seq. By mapping to the reference database, 28407, 28043, and 28683 genes were detected in the young fruit of DB1, DB2, and DK, respectively, while 28040, 22256, and 27351 genes were detected in the ful ripe stage, respectively. There were 281 differentialy expressed genes between DB1 and DK, with 123 and 158 genes up-regulated and down-regulated, respectively, and 47 differentialy expressed genes between DB2 and DK, of which 8 and 39 genes were up-regulated and down-regulated. Using real-time PCR, the expression levels of the eight functional genes at different developmental stages of the fruit were also analyzed. These comprehensive analyses showed that both mutants are different from DK, which is the result of natural doubling of ploidy, thereby generating a pleiotropic effect. As we known, it is the ifrst report to study the relationship between bayberry ploidy alterations and genes involved in regulation of fruit mutations, which wil help to identify the morphological and cytological characteristics ofM. rubragermplasm, and provide a theoretical basis and technical support for genetic improvement and creation of breeding resources.

早熟耐低温杨梅新品种早鲜的选育

早鲜是从早色杨梅种植区发现的优良变异单株选育而成的杨梅早熟新品种,果实圆球形,无果蒂凸环;完全成熟时果面呈深红色,肉柱圆钝,平均单果质量13.99 g,最大果质量可达16.06 g,可食率91.17%;可溶性固性物含量(w,后同)12.54%,总糖含量8.46%,可滴定酸含量1.09%,柠檬酸含量1.05%,维生素C含量59.88 mg·100 g^(-1),果实味甜中带酸,带有其独特的鲜味,品质上等。树势较弱,分枝少,枝梢密度较稀,树冠透风透光性好;叶色浓绿,叶片窄倒卵圆形、先端形状为钝,叶缘全缘;以中、短果枝结果为主,结果均匀,成熟后果柄与果肉容易分离,无大小年结果现象。早熟性好,在浙江杭州萧山区常年于6月6日果实成熟,比早色提早5~7 d。该品种耐低温能力较强,低温胁迫下枝条可溶性糖含量提高32.1%、相对电导率下降12.5%,适合浙北地区栽培,促进了杨梅种植区域北移。

多效唑诱导雌株杨梅形成雄花研究

【目的】杨梅为雌雄异株果树,缺少清晰明确的果实相关农艺性状的雄株杨梅品种是制约杨梅杂交研究的一个重要因素,因此研发一种诱导雌株杨梅形成雄花的技术,可为杨梅杂交新品种的选育打下扎实的基础。【方法】通过在杨梅花序原基分化阶段喷施不同浓度的多效唑水溶液,诱导雌株杨梅开雄花。【结果】‘洞口乌’杨梅的最适宜处理为在9月下旬喷施浓度为1.67 g/L的多效唑。9个参试的杨梅品种均能被诱导出雄性花序,表明外源多效唑能改变雌株杨梅的花序性别,但品种间差异显著,诱导出的雄性花序占比介于3%~100%,最高的是洞口乌杨梅,最低的是‘八贤道’杨梅。【结论】多效唑诱导雌株杨梅形成雄花的研究,为今后优特杨梅杂交新品种的选育奠定了扎实的基础,理论价值和经济效益重大。

杨梅采后保鲜研究进展

杨梅是原产于我国的特色水果,其风味独特、营养丰富,广受消费者喜爱。杨梅果实上市期短且大多数品种不耐贮运,因此采后保鲜和贮运技术对杨梅产业的健康稳定发展具有重要的影响。前人针对杨梅果实的采后保鲜和贮运问题开展了大量的研究。基于此,本文综述了杨梅果实采后的品质变化、病虫害发生规律、贮藏保鲜与物流运输技术研究进展,梳理并展望了若干研究重点,分析得出造成杨梅采性差的原因具有多样性和复杂性,提出从多方面着手形成综合技术体系的重要性。本文为杨梅采后保鲜技术研究与应用提供了一定的理论参考。

部分杨梅种质资源表型性状多样性分析

【目的】深入了解杨梅种质资源表型性状的多样性特征,为杨梅种质资源的研究和利用提供理论依据和参考。【方法】以95份杨梅地方种质资源为试材,对其果实、果核、叶片和花序等44个表型性状(20个描述型性状和24个数量型性状)观测记录,并进行相关性、聚类和主成分等分析。【结果】20个描述型性状的Shannon-Wiener指数(H)和Simpson指数(D)变化范围分别为0.5125~1.5153和0.2719~0.7660,其中果实颜色、果核核表颜色和果核茸毛颜色等表现出较高的多样性。24个数量型性状的变异系数均值为19.03%,其中果实色泽指标b^(*)值变异系数最大(63.99%)。数量型性状之间的相关性分析结果表明,72对相关系数达极显著水平,23对相关系数达显著水平。主成分分析结果表明,前8个主成分累计贡献率达81.827%,主要反映果实大小、果实色泽、果实糖酸含量等相关因子。根据聚类分析可将95份杨梅种质分为5个类群。【结论】杨梅种质资源表型性状存在丰富的多样性。其中果实单果质量、外观色泽指标、糖酸含量等可作为杨梅品质综合评定的重要指标。95份杨梅种质资源可分为5个类群,其中类群Ⅱ可用于选育大果型优质品种,类群Ⅳ可用于选育优质白梅类品种。

植物单宁对酪蛋白膜的改性研究

目的 为研究不同单宁对酪蛋白膜的改性效果,探究水解类(塔拉单宁)和缩合类(杨梅单宁)单宁在不同添加量(酪蛋白固含量的5%、10%和15%)条件下对酪蛋白膜性能的影响。方法 使用溶液浇铸法制备单宁改性酪蛋白膜,对改性薄膜的水分含量、水溶性、水蒸气透过率、不透明度、紫外光屏蔽性、拉伸力学性能、热稳定性、形貌特征、抗氧化性能及化学结构进行表征。结果 塔拉单宁的添加量与改性酪蛋白膜的水分含量和水溶性呈正相关,杨梅单宁的添加量与改性酪蛋白膜的含水率和水溶性呈负相关;单宁改性后的酪蛋白膜不透明度值上升,2种单宁均能降低酪蛋白膜的水蒸气透过率和紫外光透过率,减缓酪蛋白膜的质量损失速率,增强薄膜抗氧化性;杨梅单宁有效提升了酪蛋白膜的拉伸力学性能、热稳定性及一定的抗氧化性,杨梅单宁添加量为15%时,改性酪蛋白膜性能最佳。结论 2种单宁都能赋予酪蛋白膜更优异的紫外光屏蔽性、水蒸气阻隔性和抗氧化性,杨梅单宁对酪蛋白的交联改性效果优于塔拉单宁,可有效提高酪蛋白的拉伸力学强度和热稳定性。单宁改性后的酪蛋白膜在活性包装领域上具有一定的应用潜力。

气态臭氧结合微孔气调包装对杨梅品质和抗氧化性能的影响

本研究旨在评估气态臭氧(ozone gas,OG)和微孔气调包装(modified atmosphere packaging,MAP)对杨梅的保鲜效果。为确定杨梅保鲜的最佳贮藏条件,用不同比例的包装气体组成和不同浓度的臭氧气体对杨梅进行单独和协同处理。结果表明:10%O_(2)+10%CO_(2)+80%N_(2)和18.3 mg/m^(3)分别是杨梅贮藏的最佳气体比例和OG浓度,孔径100μm、孔数为2个/243.39 cm^(2)的微孔膜可以使MAP包装内维持最佳气体比例且处于动态平衡。单独MAP或OG处理均能显著抑制杨梅采后腐烂的发生,并维持较高的总酚、花青素和黄酮类化合物含量。MAP与OG协同处理增强了对杨梅的保鲜效果,有效减缓了其硬度的下降,降低了总可溶性固形物、可滴定酸和抗坏血酸的损失,同时将过氧化物酶和超氧化物歧化酶的活力分别提高到未经任何处理对照组的1.42倍和1.9倍,从而减少过氧化氢和超氧化物阴离子的积累,使得杨梅无霉保质期延长到8 d。

杨梅单宁-酪蛋白复合膜的制备及性能评价

采用杨梅单宁对酪蛋白膜进行改性,使用溶液浇铸法制备杨梅单宁-酪蛋白复合膜。研究不同比例的杨梅单宁对复合膜水溶性、不透明度、拉伸性能、形貌特征、水蒸气透过率、热稳定性和抗氧化性的影响。研究结果表明,复合膜的水溶性、拉伸性能、水蒸气透过率、热稳定性和抗氧化性得到有效改善。随着杨梅单宁含量的增加,复合膜的透明度下降,当杨梅单宁质量分数达15%时,复合膜的整体改性效果最优,拉伸强度较纯酪蛋白膜提高了近70.9%,水蒸气透过率下降了72.1%,DPPH自由基清除率提高了18.2%。由此可见,杨梅单宁可作为酪蛋白膜的多功能性改性剂,在食品包装领域有潜在应用前景。

Anaphylaxis and generalized urticaria from eating Chinese bayberry fruit

Chinese bayberry Myrica rubra is a very popular fruit in southeastern China.In spite of its wide consumption,no allergies to this fruit have been reported previously.Here we report on a 40-year-old woman suffering from anaphylaxis to Chinese bayberry fruit.Prick-prick skin tests revealed strong reactions to fresh Chinese bayberry fruits as well as to peach,and weaker reactions to some other fruits including apple,melon,and banana.ImmunoCAP analysis revealed identical titers of specific IgE(4.3 kU A /L) to peach extract and its lipid transfer protein(LTP,rPru p 3),which was confirmed by detection of a 9 kD band following immunoblotting.Immunoblot analysis with Chinese bayberry extract gave bands of 22,45,and 90 kD,but no 9 kD band was recognized.There was also no evidence of LTP recognition for loquat(36 kD) or melon(24 kD).This first report of a severe allergic reaction to Chinese bayberry fruit in a patient with LTP-mediated peach allergy indicates that other as yet unidentified non-pollen related fruit allergens are involved in this new severe fruit allergy.

不同简易矮化修剪方式对杨梅提质增效的影响

【目的】目前商品果产量、果实品质、劳力和农资成本等是影响杨梅种植效益的重要因素,矮化修剪成为杨梅提质增效的一个重要手段和趋势。为了更有效促进杨梅的提质增效,经对比后寻求合理的修剪方式。【方法】以10 a生‘东魁’杨梅为材料,采用“直立枝修剪”和“开天窗”等两种不同简易矮化修剪方式,比较二者对杨梅树体矮化、果实品质及种植效益的影响。【结果】两种矮化修剪方式均能显著降低杨梅树体的高度,利于农事操作。与对照相比,两种修剪方式还可显著增加果实单果重、可溶性固形物含量和果实色泽CIRG值和降低果实可滴定酸。与“开天窗”相比,“直立枝修剪”在树体矮化效果、降低果实酸含量、提高株商品果产量等方面效果更显著。两种矮化修剪方式的种植效益均优于对照,株净效益分别比对照增加261.6元和91.2元。【结论】杨梅采用“直立枝修剪”矮化修剪方式的种植效益更佳。

多效唑对杨梅枯枝病的影响及防治

检测分析不同剂量多效唑施用后在杨梅叶片、根部、果实的残留情况,以及对叶片色泽、根系、果实品质的影响；综合分析多效唑与杨梅枯枝病发生的因果关系.并针对枯枝病发生特点,利用自主研发的混配药物进行综合防治试验,并对治愈植株果实的农药残留进行随机检测.结果表明,重度、中度、轻度发病树叶片、根部多效唑含量差异显著,分别为叶片439.00,25.60,13.20μg/kg ,根部266.00,3.38,1.20μg/kg ,发病程度越高残留量越大；果实中均未检测到多效唑残留；500 mg/kg 高质量分数的多效唑处理使杨梅叶片气孔密度增大,气孔面积减小；T1（200 mg/kg）,T2（300 mg/kg）,T3（500 mg/kg）3个质量分数的多效唑连续施用与植株枯枝病轻度、中度、重度发生相对应,呈正相关；利用自主研发的混配药物对枯枝病发病植株进行防治效果显著.轻度发病树经3年连续治理后基本恢复正常生长,死树率为0,而作为对照的发病率为74.7％、死树率为21.6％；中度发病树治愈率均分别达90％以上,对照发病率为100％；严重发病树治愈率均在50％以上,对照在4年后全部死亡.经综合防治后恢复正常生长的植株果实的农药残留显著降低,克百威、甲胺磷、氧乐果和溴氰菊酯4个农药残留指标低于国家无公害标准的1～5倍,重金属铅的含量低于国家无公害标准的8倍.总之,多效唑施用后对杨梅可产生不可逆的影响,即多效唑（中高浓度多次施用）—树势早衰—拟盘多毛孢菌寄生侵染—枯枝病出现—枯枝死树—病菌扩大繁殖并加速传播,形成恶性循环,导致枯枝死树连续发生.而利用笔者的专利技术尽早采取综合防治效果明显.

多效唑对东魁杨梅生长与结果的影响

以东魁杨梅(Myrica rubra cv.Dongkui)为受试生物,研究了中、高剂量和不同施用频率的多效唑(paclobutrazol,代号PP333)处理对果树正常生长和结果的影响。实验设4个处理,分别为无PP333施用记录、5年前施用后停用、连续5年施用300mg·kg-1PP333和连续5年施用400mg·kg-1PP333。结果显示,300～400mg·kg-1PP333处理使东魁杨梅叶片硬度增大,叶片颜色加深,反卷;枝条纤维素含量增加,断枝承受力降低;果实单果重减小,可溶性固形物含量降低。杨梅叶片和树皮细胞结构的检测结果表明,300～400mg·kg-1PP333处理使叶片栅栏组织和海绵组织细胞紧缩,细胞变小,海绵组织增厚,呈失水皱缩状;树皮木质部的细胞大小和密度无明显变化,但韧皮部的细胞密度变大,细胞间空隙减小。连续施用300～400mg·kg-1的PP333会导致杨梅叶片和土壤中PP333的残留和积累。研究表明,中、高剂量的PP333对杨梅的生长和生殖均有不利影响。