蒙自小枣与金丝小枣的对比研究

用物理化学方法检测了蒙自小枣的主要性状和多种营养成分含量,试验了蒙自小枣的冷藏保鲜性能,调查了蒙自小枣的经济效益.与享誉中外的河北沧州金丝小枣和山东乐陵金丝小枣对比,主要品质相近,某些方面各有优劣.     

枣果采后转红与果皮活性氧代谢

以壶瓶枣和梨枣为试材,探索枣果采后转红与果皮活性氧代谢的关系。结果表明:枣果采后转红过程中果皮活性氧清除酶SOD、CAT活性均呈下降趋势,O_2^-生成速率、H_2O_2含量均呈上升趋势;果皮SOD活性与O_2-生成速率、H_2O_2含量均呈上升趋势;果皮SOD活性与O_2^-生成速率、CAT活性与H_2O_2含量均呈显著负相关,果皮褐变度显著增大,表明枣果采后在转红过程中抗氧化酶活性氧的清除能力降低,导致活性氧积累;枣果采后转红过程中,相对电导率增大,MDA含量增大,表明枣果果皮膜脂过氧化作用加强。说明枣果采后转红过程中果皮活性氧代谢失调,膜脂过氧化作用加强,褐变发生。     

新乡市不同土壤质地施用氮肥对优小麦产量和品质的影响研究

四种不同质地的土壤施用氮肥,对增加优质小麦的产量和提高品质的效应非常显著,其中以中壤和轻壤氮肥的农业效率优于沙土和沙壤土.每666.7m2的最佳施氮量,中壤土为15.75kg,沙土为15.51kg,轻壤土为16.79kg,沙壤土为14.47kg.施氮增产的原因是在最佳施肥水平下,穗数、穗粒数、千粒重三个产量性状同步增长所致.     

新乡市不同土壤质地施用氮肥对优小麦产量和品质的影响研究

四种不同质地的土壤施用氮肥，对增加优质小麦的产量和提高品质的效应非常显著，其中以中壤和轻壤氮肥的农业效率优于沙土和沙壤土。每666．7m。的最佳施氮量，中壤土为15．75kg，沙土为15．51kg，轻壤土为16．79kg，沙壤土为14．47kg。施氮增产的原因是在最佳施肥水平下，穗数、穗粒数、千粒重三个产量性状同步增长所致。     

梅州市主要植烟区土壤理化性质初步研究

采用野外调查、取样和室内实验分析相结合的方法,初步研究了梅州市主要植烟区土壤的理化性质,结果表明:烟区土壤质地为砂壤土或壤土;土壤容重范围值为1.0¹.3g/cm3;土壤比重平均值为2.66g/cm3;土壤孔隙度平均值为47.3%;土壤自然含水量约为19.83%;土壤pH平均值为5.05;土壤有机质含量均值约为2.0%;土壤速效钾含量平均值为187ppm,烟区土壤存在一定的潜力与不足.针对现状,提出相关建议以改善烟区土壤,保证烟叶的优质稳产.     

不同添加物对拟康木霉St-zn-9在土壤浸渍液中生长的影响

为明确添加物对木霉打破土壤抑菌能力的影响,以土壤浸渍液培养基为基础培养基,研究了不同添加物添加后木霉菌丝干质量和产孢量的变化.结果表明:不同添加物对木霉菌丝干质量和产孢量的影响不同,其中添加枣果煎汁、葡萄糖、尿素、磷酸二氢钾、马铃薯煎汁和玉米秸秆煎汁时菌丝干质量与产孢量均显著高于对照.组合培养以组合D(加入玉米秸秆煎汁和尿素)效果最佳,产孢量达到(14.17±0.38)×10~7个/mL.     

枣果中维生素C含量的测定及比较研究

本研究为测定和比较新疆和田枣、稷山板枣及酸枣中的维生素C含量,分别采用紫外分光光度法和钼蓝比色法测定新疆和田枣、稷山板枣及酸枣中维生素C的含量,结果表明,紫外分光光度法得到的结果的标准差均小于钼蓝比色法得到的结果,同时回收率也高于钼蓝比色法,因此采用紫外分光光度法测得的结果。新疆和田枣的维生素C含量为18.58mg/100g,稷山板枣的Vc含量10.93mg/100g,酸枣的维生素C含量为70.50mg/100g,各种枣果维生素C含量排列顺序为酸枣〉新疆和田枣〉稷山板枣。     

水培辣椒植株中稀土元素分布的研究

本文研究了水培辣椒植株中稀土元素的分布情况．结果表明稀土元素在水培辣椒植株和土壤种植辣椒植株中的分布相似;培养液中添加稀土元素钞的水培辣椒植株的根、茎和叶中稀土含量较对照均有增加、但对辣椒果的影响甚微．     

伊敏矿区排土场周围土壤中Cr、Cd形态分析及污染评价

本文以呼伦贝尔伊敏矿区排土场周围土壤为研究对象,采用改进BCR法提取土壤Cr、Cd化学形态,研究不同土层深度Cr、Cd各形态含量变化规律,并采用单因子污染指数和内梅罗指数评价对该区域土壤Cr、Cd污染进行评价,为进一步研究矿区土壤重金属污染来源和土壤污染修复提供科学依据。实验结果表明:土壤中Cr各形态含量呈现残渣态>可氧化态>可还原态>弱酸提取态变化趋势,各形态含量变化均与土层深度无明显关系;土壤Cd各形态含量呈现弱酸提取态>残渣态>可氧化态>可还原态变化规律,且随着土层深度增加含量明显降低。该区域土壤中Cr残渣态所占比例大于73%,Cr元素处于较稳定状态;土壤中Cd有效态重金属所占比例大于83%,极易被动植物所吸收,潜在生物污染性较大。研究区域土壤中Cd总含量超过呼伦贝尔地区土壤背景值1.37倍,土壤已经受到Cd污染;土壤中Cr总含量接近呼伦贝尔地区土壤背景值,且Cr残渣态含量比例高,土壤未受到Cr污染。土壤中Cr和Cd单因子污染指数Pi分别为0.88和1.38,内梅罗综合指数P综分别为0.91和1.44,研究区域土壤未发生Cr污染,出现了轻微Cd...     

20世纪50年代以来中国古代枣果研究述评

枣果是中国传统五果之一,因其具有重要的食用价值、药用价值、经济价值、文化价值、社会价值以及园林价值,在五果之中占据着重要地位。枣果不仅是古代重要的农业经济作物,也是商贸往来中的大宗商品,在灾荒时节甚至还可以发挥代粮功能。中国古代枣果研究对于丰富古代农业经济史的学术成果有着极其重要的价值。近年来,古代枣果研究已经取得了一定的学术成果,但仍存在着些许不足。文章对20世纪50年代以来有关中国古代枣果的相关研究成果进行回顾梳理,并指出其不足之处,提出了完善建议。     

Effects of Edible Coatings on Quality and Antioxidant Activity of <Emphasis Type="Italic">Zizyphus Jujuba</Emphasis> Miller cv. Dongzao During Storage

The development of edible coatings has been lauded with respect to their safety and effectiveness. In this study, we researched the effects of edible coatings (2% CaCl₂, 1% chitosan and 1% pullulan) on the nutrient content and antioxidant abilities of jujube (Zizyphus jujuba Miller cv. Dongzao). Using the new analysis technique for order of preference by similarity to ideal solution (TOPSIS), we evaluated the effects of these coatings. Compared with the control fruit group, test results showed that coating treatment significantly delayed fruit senescence. Specifically, CaCl₂ treatment not only maintained fruit storage quality and antioxidant activity but also restrained the production and accumulation of malondialdehyde in jujube. Chitosan treatment delayed decreases in secondary metabolites and superoxide dismutase and catalase activity. Pullulan coatings performed better in terms of proanthocyanidin and cyclic adenosine monophosphate (cAMP). We also used TOPSIS to evaluate the preservation effect of different film coatings and found 2% CaCl₂ to be the best treatment for jujube, followed by 1% chitosan and 1% pullulan. Based on the appropriate materials and concentration of the film coatings, edible coatings have the potential to retain the quality and antioxidant capacity of the Chinese jujube cv. Dongzao.     

Research advances in bioactive components and health benefits of jujube (Ziziphus jujuba Mill.) fruit

Jujube(Ziziphus jujuba Mill.), a highly nutritious and functional fruit, is reported to have various health benefits and has been extensively planted worldwide, especially in China. Many studies have shown that bioactive components derived from jujube fruit have significant nutritional and potential biological effects. In this paper, the latest progress in research on major bioactive compounds obtained from jujube is reviewed, and the potential biological functions of jujube fruit resources are discussed. As a dietary supplement, jujube fruit is well recognized as a healthy food which contains a variety of bioactive substances, such as polysaccharides, polyphenols, amino acids, nucleotides, fatty acids, dietary fiber, alkaloids, and other nutrients. These nutrients and non-nutritive phytochemicals obtained from jujube fruit have physiological functions including anticancer, antioxidant, anti-inflammatory, anti-hyperlipidemic, anti-hyperglycemic, immunoregulatory, neuroprotective, sedative,and antiviral functions. Of note is that new constituents, including alkaloids, dietary fiber, and other bioactive substances, as well as the antiviral, hypoglycemic, lipid-lowering, and neuroprotective effects of jujube fruit, are systematically reviewed here for the first time. Meanwhile, problems affecting the exploitation of jujube fruit resources are discussed and further research directions proposed. Therefore, this review provides a useful bibliography for the future development of jujube-based products and the utilization of jujube nutritional components in functional foods.     

Effects of Edible Coatings on Quality and Antioxidant Activity of Zizyphus Jujuba Miller cv. Dongzao During Storage

The development of edible coatings has been lauded with respect to their safety and effectiveness.In this study,we researched the effects of edible coatings(2%CaCl_2,1%chitosan and 1%pullulan) on the nutrient content and antioxidant abilities of jujube(Zizyphus jujuba Miller cv.Dongzao).Using the new analysis technique for order of preference by similarity to ideal solution(TOPSIS),we evaluated the effects of these coatings.Compared with the control fruit group,test results showed that coating treatment significantly delayed fruit senescence.Specifically,CaCl_2 treatment not only maintained fruit storage quality and antioxidant activity but also restrained the production and accumulation of malondialdehyde in jujube.Chitosan treatment delayed decreases in secondary metabolites and superoxide dismutase and catalase activity.Pullulan coatings performed better in terms of proanthocyanidin and cyclic adenosine monophosphate(cAMP).We also used TOPSIS to evaluate the preservation effect of different film coatings and found 2%CaCl_2 to be the best treatment for jujube,followed by 1%chitosan and 1%pullulan.Based on the appropriate materials and concentration of the film coatings,edible coatings have the potential to retain the quality and antioxidant capacity of the Chinese jujube cv.Dongzao.     

Phenolic profile of jujube fruit subjected to gut microbiota fermentation and its antioxidant potential against ethyl carbamate-induced oxidative damage

Objective: To evaluate the composition of bioactive substances and the antioxidant effects of jujube fruit under gut microbiota fermentation(GMF), and the inhibitory effect on cytotoxicity caused by ethyl carbamate(EC). Methods: Changes in the contents of flavonoids, polyphenols, total sugars, and reducing sugars of jujube fruit after GMF(0, 2, 6, 12, 24, and 48 h)were determined. The oxidation resistance of fermented jujube fruits(from 0 to 48 h fermentation) was evaluated using in vitro2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate)(ABTS) and ferric reducing antioxidant power(FRAP) assays. Inhibitory effects of 48 h-fermented jujube fruit at various concentrations(0.25, 0.50, 1.00, and 2.00 mg/m L) on EC-treated toxicity and DNA damage of Caco-2 cells were estimated using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2 H-tetrazolium bromide(MTT)and nuclear staining assays, respectively. Effects of different concentrations of jujube fruit on EC-treated Caco-2 cells' intracellular reactive oxygen species(ROS), glutathione(GSH) levels, and mitochondrial membrane potential(MMP) were also evaluated. Results: Jujube fruit has rich bioactive components after GMF and shows strong antioxidant capacity. Fermented jujube fruit can inhibit the cytotoxicity and DNA damage of Caco-2 cells caused by EC and reduce intracellular ROS generation, as well as restoring GSH and MMP. Conclusions: Fermented jujube fruit extracts produced by GMF still contain biologically active substances which retain biological activity and antioxidation capabilities.     

施锌对沙田柚果实品质的影响

锌是沙田柚生长过程中的不可缺少的微量元素之一,梅州市果园多为红壤、黄壤,土层深厚而瘦瘠,是锌缺乏土壤。在田间生长条件下,研究了施锌对沙田柚果实含酸量、维生素C含量和可溶性固形物含量的影响。结果表明:施用锌肥可增加柚果可溶性固形物,降低含酸量,较明显地提高其糖酸比,并增加维生素C的含量,从而提高柚果品质。     

三门峡黄河滩地土壤特性分析

本文对三门峡黄河滩地土壤进行了吸湿水含量、酸碱度、有效氮、有效磷和有机质含量分析。研究结果表明:河滩地种植黄豆可以改良土壤质地,调节PH值,增加土壤有效氮、有效磷和有机质含量,提高土壤肥力。     

Application of a chitosan coating as a carrier for natamycin to maintain the storage quality of ground cherry (<Emphasis Type="Italic">Physalis pubescens</Emphasis> L.)

Ground cherry (Physalis pubescens L.) is a kind of berry fruit favored by consumers in China; however, this fruit is particularly vulnerable to physiological senescence and pathogen attack during the traditional cold storage period. In order to maintain storage quality, a 1.5% (w/w) chitosan (CS) water solution containing 50 mg/L of natamycin (NA) was introduced. After all treatments were completed, the fruit was stored at 0 °C and sampled every 10 d. At each sampling date, the following tests were performed: mold and yeast analyses; enzyme activity and content analyses which included superoxide dismutase (SOD), ascorbate peroxidase (APX), and malondialdehyde (MDA); and color analysis. In addition, a sensory evaluation was carried out for quality assessment at the end of the storage period. The results showed that the application of a chitosan coating combined with natamycin (CSNA) enhanced the activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX), reduced the physiological rate of senescence, and inhibited pathogen attack. Thus, CSNA treatment can maintain ground cherries at an acceptable level of storage quality for 50 d.     

武夷山不同土地利用方式对其土壤养分的影响

通过对武夷山进行实地考察,选取了竹林（坳头）,杉木林（桐木关西侧）,茶园（挂墩）3个不同土地利用方式下的土壤剖面,并通过室内理化分析实验,测定剖面土壤的有机质总量、全氮含量及其机械组成,研究土地利用方式对其土壤养分的影响.通过实地考察和室内理化分析实验,得到以下主要结论：（1）竹林、杉木林和茶园的土壤机械组成以壤质土为主;（2）茶园、杉木林、竹林的土壤黏粒含量差别不大;（3）在A层中,不同土地利用方式下土壤有机质含量大小顺序为竹林〉茶园〉杉木林;而在B层中,土壤有机含量大小顺序为竹林〉杉木林〉茶园;（4）在A层中,不同土地利用下土壤全氮含量大小顺序为竹林〉茶园〉杉木林;而在B层中,土壤全氮含量大小顺序为竹林〉杉木林〉茶园;（5）土地利用方式影响着土壤的养分含量,不同的土地利用对土壤养分有着不同的影响.