厚藤Ipomoea Pes-Caprae(L.) Sweet的化学成分研究(Ⅰ)

目的从厚藤(IpomoeaPes-Caprae(L.)Sweet)的乙酸乙酯提取物中分离到7个化合物。方法采用柱层析技术、经理化常数和波谱分析进行结构鉴定。结果它们分别是β-香树素(1)、12-ursen-3-ol(2)、β-谷甾醇(3)、豆甾醇(4)、α-菠甾醇(5)、异莨菪亭(6)和七叶内酯(7)。结论其中异莨菪亭和七叶内酯为首次从该植物中分离得到。

Nutritional Quality of Mixed Silage of Lablab purpureus and Sweet Sorghum

[ Objective ] The paper was to evaluate the fermentation quality of mixed silage of Lablab purpureus and sweet sorghum, and to find out the appropriate mixing ratio. [ Method] L. purpureus were mixed with sweet sorghum at different proportions, to identify the sensory character and quality of silage. [ Result] The nutrient content of mixed silage of L. purpureus and sweet sorghum at different proportions decreased significantly at 30 - 60 d, while no significant changes were observed after 60 d. Mixed silage of L. purpureu.s and sweet sorghum had the best effort at the proportion of 3：7 ; followed by the proportion of 5： 5. These two proportions significantly improved dry matter （DM） content and effectively alleviated the crude protein （CP） loss of raw materials; significantly improved the contents of crude fiber and crude ash; and significantly reduce ammonia nitrogen/total nitrogen （AT/TN）. [ Conclusion ] From the perspective of silage quality, the appropriate mixing ratio ofL. purpureus and sweet sorghum is 3：7 or 5：5.

Leaf Turgor Potential, Plant Growth and Photosynthesis in Organically Fertilized Sweet Corn

A greenhouse pot experiment was conducted using a complete random design with six replications. A pressure-volume curve analysis was employed to study the effects of organic fertilizers on plant water relations in sweet corn (Zea mays L. cv. Honey-bantam) in terms of leaf osmotic concentration (Cs), osmotic potentials at full turgid status (πFT) and at incipient plasmolysis (πIP), and of symplastic (ζsym) and apoplastic (ζapo) fractions in the tissue water compartment in relation to photosynthetic capacity (Pc) and dry mass accumulation. At the seedling stage (day 15), plants with chemical fertilizer treatments showed lower πFT, πIP and ζapo and higher Cs, ζsym and PC than those with organic fertilizer treatments. Compared to PC and relative growth, where values from day 15 to day 75 were first lower for organic treatments and then higher, ζsym and Cs values were similar, while πFT and πIP were opposite being higher then lower. Dry mass production with organic fertilizer was higher than or close to the chemical fertilizer treatments in the later growth stage (day 75), though dry mass production with chemical fertilizers was much higher in the early and middle growing stages (days 15 and 45). Increased photosynthesis and dry mass production in later growth stages due to organic fertilizers were associated with increased osmotic concentration in the tissue and the symplastic fraction of the tissue water compartment. These might favor stomatal opening and biochemical activities.

The Comparison of Sugar Components in the Developing Grains of Sweet Corn and Normal Corn

The sugar components and their dynamic variation in the developing grains of sweet corn(Zea mays L. seccharata Sturt)and normal corn (Zea mays L. indentata Sturt) were compared. There are WSP (water-soluble polysaccharides), sucrose, fructose, glucose, mannitol and sorbitol in both sweet corn and normal corn, but no maltose. Two components with different degrees of polymerization (D. P. N) were detected in the sweet corn; only one of them was detected in the normal corn 20 days after pollination. With the development of grains, the total soluble sugar content(TSS)in sweet corn increased, but in normal corn it decreased. The dynamic variation of WSP, sucrose, glucose, fructose, mannitol and sorbitol in sweet and normal corn grains are different. The contents of sugar components in the sweet corn grains are higher than that in the normal corn. Sweet corn accumulates less starch than normal corn.

Co-Treatment of EFF and 1-MCP for Enhancing the Shelf-Life and Aroma Volatile Compounds of Oriental Sweet Melons(Cucumis melo var.makuwa Makino)

Compared to other melon types, oriental sweet melon （Cucumis melo var. makuwa Makino） is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of this experiment is to explore the effects of co- treatment of enhanced freshness formulation （EFF） and 1-methylcyclopropene （1-MCP） on physiological changes and the content of aroma volatile compounds introduced by them of two oriental sweet melon cultivars （Yumeiren and Tianbao） during storage. The melons were stored in incubators with temperature of 15~C and a relative humidity of 85% for 24 d during which fruit quality and related physiological index were measured. Compared to the control, both treatments delayed fruit weight loss rate and kept the fruit firmness, water content and soluble solids content. Ascorbate peroxidase （APX） and phenylalanine ammonia lyase （PAL） activities showed fluctuations in treated melons, while lipoxygenase （LOX） activity （P〈0.01） and malondialdehyde （MDA） content （P〈0.05） decreased compared to control. During the early stage of storage, alcohols and aldehydes were the main volatile compounds, and esters gradually increased during storage. Of all the esters, acetic esters were the main components, followed by oxalic acid esters and other esters. The total content of aroma volatile compounds, esters, alcohols and aldehydes of co-treated melons were all higher than those of 1-MCP treated and control melons. In addition, the aroma volatile peak of co-treated melons occurred later than that of 1-MCP treated and control melons. In summary, co-treatment of EFF and 1-MCP was more beneficial than 1-MCP treatment to delay ripening and senescence, maintain fruit quality, enhance shelf-life and improve levels of aroma volatile compounds.

Typical HPLC Chromatogram of Petroleum Ether in Abutilon indicum(L.) Sweet from Different Habitats

[Objectives] To study the typical HPLC chromatogram of petroleum ether in Abutilon indicum (L.) Sweet from different habitats, in order to provide experimental basis for the quality control of A. indicum and the spectrum-efficacy relationship of petroleum ether.[Methods] The HPLC chromatogram of petroleum ether was obtained using Agilent SB-C 18 (4.6 mm×250 mm, 5 μm) and acetine-0.1% phosphoric acid solution for gradient elution at temperature of 30 ℃, flow rate of 1.0 mL/min and detection wavelength of 205 nm.[Results] The typical HPLC chromatogram of petroleum ether in A. indicum was preliminarily established, with 12 characteristic peaks. It was verified by A. indicum from different habitats, characterized by reproducibility and stability.[Conclusions] Typical HPLC chromatogram provides a stable new method for the quality control of petroleum ether in A. indicum . This study provides experimental basis for further study on the medicinal parts of A. indicum .

Identification and Quantification of Allelochemicals from Selected Sweet Potato (<i>Ipomoea batatas</i>(L.) Lam.) Cultivars

Allelopathic compounds have the potential to inhibit the growth and development of other organisms in a diverse manner ranging from shifting nutrients and enhancing their growth to inflicting diseases. In addition, these compounds influence seedling growth and seed germination of various crops. The goal of this study was to identify and quantify different allelochemicals in various sweet potato cultivars through high-performance liquid chromatography techniques. Selected sweet potato slips (weight: 2.0 - 2.5 grams/slip) were propagated in separate glass tubes filled with 10.0 mL distilled water. Water extract from each glass tube was collected after 2, 4, and 6 weeks after transplanting (WAP) to identify and quantify allelochemical compounds by comparing their peaks with the retention time of standards. Results show that the concentration of allelochemicals in water extract was increased from 2 to 4 WAP but remained constant in the sixth week. Quantitative analysis revealed that the amount of chlorogenic acid was higher in all sweet potato cultivars compared to other allelochemicals. Some sweet potato cultivars, A5 and A39, exhibited higher allelopathy (18.28 - 19.37 ppm/slip) and reduced the height and biomass of Palmer amaranth the most due to the presence of increased concentration of combined allelochemicals, while other cultivars produced lesser allelochemicals (10.90 ppm/slip) and did not reduce the growth of the weed species. Allelopathic sweet potato cultivars high in chlorogenic acid production can effectively suppress Palmer amaranth with minimal dependence on chemicals to manage weeds and harmful pests under sustainable agricultural system.

腈吡螨酯对扁豆二斑叶螨的田间药效及安全性评价

二斑叶螨是扁豆主要害虫之一,发生较重时可降低扁豆产量和品质。本研究评价了30%腈吡螨酯悬浮剂对扁豆二斑叶螨的田间药效及其对扁豆的安全性。田间使用有效成分量67.5、90、112.5 g/hm2,药后1 d三地的田间防效66.5%~85.9%、药后3 d 82.1%~92.3%、药后7 d 86.9%~95.2%、药后14 d 80.9%~96.1%,能有效防控扁豆二斑叶螨,具有较好的速效性和良好的持效性。作物安全性试验表明30%腈吡螨酯悬浮剂对扁豆安全。建议登记30%腈吡螨酯悬浮剂防治扁豆二斑叶螨,推荐使用有效成分量67.5~112.5 g/hm^(2)(制剂量15~25 mL/667m^(2)),于二斑叶螨发生初期施药1次。

子粒镉低积累型甜糯玉米材料的筛选

为筛选出在不同土壤镉(Cd)浓度胁迫下子粒Cd低积累型的甜糯玉米(Zea mays L.)材料,以45份甜糯玉米材料为对象,采用盆栽试验,设置2个土壤添加外源Cd处理,即C1(1.3 mg/kg)和C2(3.2 mg/kg),以不额外添加Cd为对照(CK),对甜糯玉米材料子粒Cd的积累差异进行研究。结果表明,甜糯玉米子粒Cd含量随土壤中Cd浓度的增加而增加,且在材料间存在极显著差异(P<0.01)。不同Cd浓度下,所有甜糯玉米材料子粒Cd的富集系数均小于1。聚类分析发现,有15份材料在不同Cd浓度下均表现出子粒低积累特性,其中S18、S29、S30、S36和S44这5份材料子粒的Cd含量在不同处理下均小于食品安全国家标准的0.1 mg/kg,说明这5份材料可作为子粒Cd低积累型亲本材料,为甜糯玉米Cd安全品种的培育提供种质资源。

油菜—富硒水稻—富硒甘薯轮作对土壤养分及甘薯的影响

为掌握油菜—富硒水稻—富硒甘薯轮作种植模式(T)与传统冬闲—水稻—甘薯种植模式(CK)的差异,特开展种植试验,分析甘薯收获后土壤pH值、有机质、全氮、碱解氮、速效钾、交换性钙、有效锌和有效硼的含量,甘薯可溶性糖、维生素C含量,以及大米和甘薯的硒元素含量。结果表明,与CK相比,T处理的土壤肥力和甘薯品质明显提升,其中0~20 cm土壤的有机质、全氮、碱解氮、速效钾、交换性钙、有效锌和有效硼分别提升21.8%、3.2%、5.4%、28.4%、34.6%、42.5%、300.0%,20~40 cm土壤则分别提高22.8%、5.6%、14.0%、32.6%、38.0%、104.4%、325.0%;甘薯总糖、维生素C含量分别提高125.09%、16.34%。另外,通过施用富硒肥,T处理的大米和甘薯硒元素含量分别达到0.14、0.15 mg/kg。因此,油菜—富硒水稻—富硒甘薯轮作种植模式(T)可实现油菜绿肥还田及水稻、甘薯秸秆还田,达到改良土壤、提升甘薯品质的目标。

米根霉发酵甘薯淀粉制备L-乳酸研究

以米根霉AS3.819的诱变株为菌种,甘薯淀粉为碳源,在摇瓶发酵工艺的基础上,利用10L发酵罐对该菌株产L-乳酸进行研究,探索出10L罐最适发酵条件为:装液量40%,搅拌转速400～650r/min,通气流量0.5～0.6L/(L·min),溶氧≥88%,温度32℃,pH5.0～5.5,消泡剂添加量0.1%左右。罐发酵结果得到L-乳酸累积浓度为99.54g/L,对原淀粉的转化率达77%,最高生物量7.2g/L,发酵周期70h。

甜玉米穗位叶面积QTL定位

选用穗位叶面积有显著差异的超甜玉米（Zea mays L.）自交系T4和T19为亲本配制杂交组合，以232个单株的F2群体为作图群体，构建了一张包含77个位点全长868.7 cM的玉米SSR标记遗传连锁图谱，标记间的平均间距为11.28 cM。在F2群体中用复合区间作图法在玉米全基因组上检测穗位叶面积QTL，共检测到4个与甜玉米穗位叶面积相关QTL，分别位于玉米第4、5、9染色体上，可解释5.98%~11.12%的表型变异。这一结果将加快高产、耐密和抗倒伏甜玉米育种进程，实现玉米的分子标记辅助选择育种。

米根霉发酵甘薯淀粉制备L-乳酸的最适条件

以米根霉AS.3.819的诱变株为菌种、甘薯淀粉为碳源,对其摇瓶发酵生产L-乳酸工艺进行研究。结果表明,采用不同质量分数的液化甘薯淀粉、(NH4)2SO4、KH2PO4、ZnSO4·7HO2及MgSO4·7HO2作为发酵培养基组分,在温度为32℃和发酵时间为60h的条件下,L-乳酸质量浓度最大可以达到125g/L,糖转化率达到92.60%。

甘薯叶绿体rbcL基因的克隆与序列分析

根据烟草、水稻和菠菜叶绿体的全基因组序列设计引物,以甘薯的叶绿体基因组DNA为模板,PCR扩增包含甘薯叶绿体rbcL完整基因(GenBank登录号为AY942199)在内的一段序列。序列分析表明:此片段的全长为1627bp,包括1443bp的编码区序列在内,推测编码480个氨基酸,同时构建了此片段的限制性酶切图谱。相似性比较显示,此基因编码区序列与烟草、菠菜、小麦、水稻、玉米、矮牵牛、紫花苜蓿、拟南芥、莨菪、葡萄以及甜菜的rbcL基因核苷酸的同源性为85%～98%,氨基酸的同源性为92%～95%。

低糖马齿苋紫薯酱加工工艺优化及其产品品质评价

为了满足消费者对口味多样化、健康饮食的需求,开发一种低糖、零防腐剂的新型复合果酱的科学配方和先进制造方法。以富含人体健康功能因子的马齿苋和紫薯为主要原料,通过单因素实验和正交试验优化了马齿苋紫薯酱的配方,并对最终产品及其贮藏期间的营养物质、理化和卫生指标进行了测定。结果表明,低糖马齿苋紫薯酱的最佳配方为:马齿苋茎叶汁紫薯块根浆质量比为5:5,柠檬酸添加量为0.3%,山梨糖醇添加量为25%,增稠剂添加量为0.4%。按此配方制得的马齿苋紫薯酱色泽呈紫红色,酱体均匀,口感细腻,酸甜适中,具有马齿苋和紫薯特有的香味,感官评分为90.5±0.4分。最终产品的可溶性固形物为42.32%±1.43%,总糖为13.41±0.52 g/100 g,pH3.61±0.18,粗蛋白为0.83±0.08 g/100 g,VC为3.77±0.11 mg/100 g,黄酮为4.18±0.10 mg/g,多酚为2.05±0.13 mg/g,花青素为37.27±0.84 mg/100 g,以上理化指标及卫生指标均达到果酱类的国家标准。马齿苋紫薯酱对DPPH自由基的IC50值为7.071 mg/mL,表明该酱具有一定的抗氧化活性。马齿苋紫薯酱分别在25℃和37℃条件下贮藏1个月后,感官评分及各营养成分均有一定程度下降,菌落总数有所增加,但仍符合果酱国家标准。本项研究结果可为马齿苋和紫薯的精深加工及马齿苋紫薯酱的标准化生产提供参考依据。

黄曲霉发酵薯干粉水解液生产L－苹果酸

经选育和诱变得到一株产苹果酸的黄曲霉菌ＴＨ５００７，通过发酵条件的优化，以薯干粉的水解液为主要原料，发酵５ｄＬ－苹果酸可达到６％左右。在总酸中苹果酸含量平均达７２％以上，杂有机酸主要是柠檬酸，延胡索酸的含量在０．０２％以下。补糖发酵比分批发酵产酸性能更佳。

番荔枝中一个SWEET家族基因的克隆与表达分析

以番荔枝不同组织样品为材料,通过基因文库筛选,利用RT-PCR技术克隆出1个1227 bp的基因,命名为AT-SWEET16-1,该基因编码408个氨基酸,该氨基酸序列在N端以α螺旋形成THB结构域。生物信息学分析结果表明,该蛋白分子量为44.8 kDa,等电点为8.87。进化分析结果发现其与海枣(Phoenix dactylifera)相类聚。qRT-PCR分析结果表明,该基因在植株的根、茎、嫩叶、老叶、花蕾、花苞、幼果、成熟果中均有表达,AT-SWEET16-1基因在不同组织中的表达量依次是:成熟果>茎>根>花蕾>幼果>老叶>嫩叶;该基因在不同果实发育阶段中的表达情况为:在果实不同发育阶段,果柄中的表达量最高,果肉、果皮中则相对较低,种子中最低;但果实成熟期该基因在果柄、果肉中的表达量最高。原位杂交实验观察发现,基因表达位置为果柄韧皮部、果肉细胞膜间,结合基因表达分析结果,预示该基因在植株糖分积累与转运等方面起到一定的作用。

不同西洋梨品种果实糖酸组分及含量分析

为了给梨果实综合评价及产业品种结构调整提供理论依据,以烟台市十个代表性果园三个西洋梨品种(‘巴梨’‘三季梨’和‘红茄梨’)为研究对象,采用高效液相色谱法(HPLC)测定果实中可溶性糖和有机酸的组分及含量。研究结果表明:在三个西洋梨品种中,总糖含量和甜度值最高的是‘红茄梨’,‘三季梨’次之,‘巴梨’的总糖含量最少;三种西洋梨成熟果实可溶性糖积累以葡萄糖和果糖为主,可溶性糖含量由高到低为葡萄糖>果糖>山梨醇>蔗糖;另外,三种西洋梨果实总酸含量差异不显著,有机酸积累以柠檬酸和苹果酸为主,这两种酸占有机酸总量的90%左右;‘红茄梨’甜酸比和糖酸比最高,显著高于‘巴梨’,与‘三季梨’差异不显著。综上所述,‘红茄梨’糖酸风味优异,可作为烟台地区西洋梨产业结构调整的备选推广品种。

米根霉Fp-6利用红薯发酵生产L-乳酸

以高产淀粉的优质红薯品种为原料,采用生产菌株米根霉Fp-6研究不同的红薯预处理方式对高光学纯度L-乳酸发酵的影响,并进行了50 L发酵罐放大试验。结果表明:用制备的红薯淀粉为原料,产酸和发酵周期均与以玉米淀粉为原料相同。当红薯液化液中的有机N含量高于0.25 g/L时,产乳酸量和糖转化率明显下降,副产物富马酸和甘油浓度明显增加,菌体量显著增加。无机N对发酵产酸有促进作用。用去除红薯中部分有机N的液化液进行发酵,在50 L罐中其产乳酸量达91.3 g/L,糖转化率为81.28%,发酵周期48 h。

米根霉薯渣固态发酵产L(+)-乳酸的研究

以甘薯渣为原料,对米根霉PW352固态发酵产L(+)-乳酸的发酵条件进行了研究。采用单因素试验、均匀设计、正交设计等方法确定最优固态发酵培养基组成为:干薯渣10g/250ml三角瓶、(NH4)2SO41. 5%、MgSO40. 2%、Zn SO40. 05%、MnCl20. 05%、葡萄糖0. 5%、吐温80 0. 05%,在接种量为1. 0×107个孢子/10g干培养基、湿度70%、中和剂碳酸钙30%、36℃条件下,发酵72h产L(+)-乳酸达38. 36(±0. 51)%(w/w),对淀粉糖的转化率为62. 5%。