大豆异黄酮的抑菌作用

以从脱脂豆粕中提取的总大豆异黄酮为实验材料研究其抑菌作用,实验结果表明,大豆异黄酮对金黄色葡萄球菌、藤黄微球菌、腊状芽孢杆菌、短小芽孢杆菌、枯草芽孢杆菌、单增李氏菌、白色念珠菌、梨头霉菌和米曲霉均有明显的抑制作用,其最低抑细菌浓度(MIC)分别为0.03%、0.09%、0.02%、0.03%、0.03%、0.05%、0.05%、0.05%和0.05%,但对大肠杆菌和酿酒酵母无抑制作用.用本实验室开发的大豆异黄酮糖苷酶将提取的总大豆异黄酮进行酶解,并将酶解后的产物进行分离纯化,得到游离型的苷元.游离型苷元和结合型糖苷的抑菌结果显示,大豆异黄酮中具有抑菌活性的成分是其游离型的苷元.其热稳定性好,经121℃、30min湿热灭菌处理后仍具有较强的抗菌活性.     

甘蓝型油菜表皮蜡粉遗传规律及其抗逆效应研究

油菜表皮蜡粉是油菜抵御外界不利因素的屏障之一,对其开展研究有益于选育抗逆稳产的油菜品种,改进栽培技术。本研究以我们发现的光叶突变体DL22B077-1和有蜡粉野生型DL22B077-2为材料,通过杂交、回交和自交等手段研究了该性状的遗传规律,结果表明,突变体DL22B077-1的光叶性状受显性单基因控制。然后利用气相色谱法检测了突变体与野生型叶片和茎秆蜡粉含量及其组成,结果发现野生型叶片和茎秆表皮蜡粉含量分别为47.40μg/cm²和76.93μg/cm²,光叶突变体叶片和茎秆蜡粉含量分别为40.40μg/cm2和61.01μg/cm²,与野生型相比,分别减少14.77%和20.79%,差异均达到显著水平(P=0.05)。而且无论是光叶突变体还是野生型,叶片蜡粉含量均低于茎秆表皮含量,差异也达到显著水平(P=0.05)。蜡粉组成成分间的差异既存在于光叶与野生型间,也存在于植株的叶片与茎秆之间。光叶突变体与野生型间蜡粉成分总体上相似,但是4种成分差异显著,其中三种(正三十六烷、十六烷氧基硅烷和15-Triacontanon...     

蛋黄果水溶性多糖含量测定

采用苯酚-硫酸法,测定蛋黄果中水溶性多糖的含量。结果表明：蛋黄果水溶性多糖含量较高,且在5～95 μg/mL的范围内,样品的浓度与吸光度有良好的线性关系,线性回归方程Y＝0.009X－0.007 8(r＝0.999 3),加标回收率101.8% (n＝5,相对标准偏差＝1.59% ),蛋黄果水溶性多糖的平均含量为8.66%。     

9种生物农药对人参立枯病菌的室内毒力测定

为筛选出防治人参立枯病的有效药剂,采用菌丝生长速率法测定了9种生物农药对人参立枯病菌(Rhizoctonia solani)的室内抑菌效果。结果表明:50亿CFU/g多粘类芽孢杆菌WP对人参立枯病菌的室内抑菌效果最好,其EC50为5.12E-09 mg/L;另外,300亿/g内生芽孢杆菌WP、10亿活芽孢/g枯草芽孢杆菌WP、1000亿芽孢/g枯草芽孢杆菌WP和10%多抗霉素WP 4种生物农药对人参立枯病菌也表现出了较好的室内抑菌效果,EC50分别为0.0001、0.0017、0.0177和0.0260 mg/L。该研究筛选出了能有效抑制人参立枯病菌菌丝生长的生物农药,对人参立枯病的科学防治具有指导意义。     

防治胡椒瘟病生物农药筛选及其盆栽药效试验

胡椒瘟病是危害中国胡椒产业的首要病害,目前主要依赖使用化学农药防治,筛选应用生物农药是减少化学农药用量的有效途径。本文通过室内毒力测定和室外盆栽药效试验,测定了5种生物农药对胡椒瘟病的防治效果。结果表明:室内毒力测定木霉菌WP、枯草芽孢杆菌WP和Z菌株发酵液对胡椒瘟病病原菌的抑菌效果好且敏感性高,EC50分别为0.49、0.78、1.13μg/m L;盆栽药效试验Z菌株发酵液和枯草芽孢杆菌WP对胡椒瘟病防效最好,平均防效分别为83%和82%,芽孢杆菌/淡紫拟青霉WP的防效次之,平均防效为69%。综合来看,Z菌株发酵液和枯草芽孢杆菌WP对胡椒瘟病具有很好防效,具备良好的绿色防控潜力。     

7株拮抗菌的鉴定及其对香蕉炭疽病的防治作用

为了收集利用香蕉炭疽病的生防菌资源和评价拮抗菌的防病能力,通过培养性状与形态特征观察、生理生化反应和16S r RNA序列特征分析等方法对筛选到的7株拮抗菌进行鉴定,并对其防病作用进行了初步测试。结果表明:菌株Bb7802、Bb7304、Bb7202、Bb7108、Bb7004和Bb5911为短短芽孢杆菌,菌株Bc6301为蜡状芽孢杆菌。人工接种结果表明,菌株Bc6301对香蕉炭疽病的防效最高,为45.94%,其余6株拮抗菌的防效在22.35%~43.29%。     

贵州主栽杧果品种果实品质及香气成分分析

为了解贵州主栽杧果品种的果实品质特性,分析了‘金煌杧’‘贵妃杧’‘玉文杧’‘桂七杧’‘红玉杧’5个主栽杧果品种果实的12个品质指标和香气成分。结果表明：5个杧果品种的平均单果重在380~898 g,果形指数在1.60~2.14,可食率72.10%~77.74%,水分含量82.06%~85.10%,总灰分含量1.30%~1.70%,粗纤维含量在0.90%~1.10%,可溶性糖含量在7.75~13.90 g/100 g,可溶性固形物含量在11.05%~17.10%,总酸含量在0.120~0.233 g/100 g,维生素C含量在0.0018~0.0073 g/100 g,糖酸比在40.26~123.88,固酸比在61.30~153.39;5个杧果品种共检测出50种香气成分,以萜烯类化合物为主;‘金煌杧’‘贵妃杧’‘玉文杧’‘桂七杧’‘红玉杧’分别检测出香气组分14种、14种、21种、21种、16种,其中萜烯类化合物的含量分别达56.34%、73.95%、82.47%、97.32%、64.16%。5个杧果品种的香味均以松木香味为主,略带青香、苹果香和柠檬香等香味。     

两季贡菊花生理生化指标及活性成分测定

研究了黄山贡菊的两季花突变种基本的形态学特征,并采用可见光分光光度计、紫外分光光度计、毛细管电泳等方法对其生理生化指标和活性成分进行了测定。结果显示,叶片及茎中可溶性糖的含量分别为3.00和3.65μg/m g,可溶性蛋白的含量分别为2.08和0.57μg/m g,总叶绿素的含量为0.52 m g/g。逆境处理后,游离脯氨酸和丙二醛的含量分别达到106.90和12.18μm o l/g。叶片组织提取的酶液中过氧化物酶的活性为8.73 u/g(组织),过氧化氢酶最大酶活为36.5 u/g.m in。商品干花中,总黄酮的含量为5.17 m g/g;挥发油常温下为蓝绿色,得率为0.36%;绿原酸的含量为0.57 m g/g。     

海南产木薯茎和叶挥发油的化学成分及其生物活性(英文)

为研究木薯茎和叶的挥发油成分,采用气相色谱-质谱(GC-MS)联用方法对其化学成分进行分析,鉴定了茎的挥发油中25个成分和叶挥发油中22个成分,分别占总挥发油含量的83.53%和83.46%。其中茎挥发油主要成分为棕榈酸(31.39%)、油酸(8.94%)、亚油酸(5.57%),叶挥发油主要成分为棕榈酸(16.85%)、植醇(15.02%)、异植醇(11.21%)。用滤纸片琼脂扩散法测定茎和叶挥发油的抗金黄色葡萄球菌活性和抗耐甲氧西林金黄色葡萄球菌(MASA)活性,结果表明:茎的挥发油具有抗金黄色葡萄球菌活性;叶的挥发油具有抗MASA活性。细胞毒活性结果表明,茎的挥发油对人慢性髓原白血病细胞K562有显著细胞毒活性,其IC50值为7.0μg/mL。     

乙酰化蛋黄果多糖及其抗氧化活性研究

蛋黄果（Lucuma nervosa A. DC）乙酰化修饰多糖的抗氧活性优于未修饰多糖,通过分析乙酰化蛋黄果多糖的乙酰化度、红外光谱和形貌特征,阐明引起抗氧活性提升的原因。试验采用超声波辅助法提取蛋黄果果肉粗多糖,用三氯乙酸法除去蛋白质得到多糖。选取3份0.50 g多糖加入20% NaOH溶液溶解,分别加入1、3、5 mL乙酸酐,得到3种取代度（0.237±0.05、0.275±0.07、0.228±0.04）的乙酰化蛋黄果果肉多糖,评价其清除DPPH自由基、OH自由基和ABTS自由基的能力。结果表明,乙酸酐添加量由少到多时,蛋黄果多糖乙酰基取代度先显著升高,后趋于平缓下降。乙酰化蛋黄果多糖的红外光谱显示了3417 cm^-1（-OH）、2950 cm^-1（-CH）处的伸缩振动和1636 cm^-1处的（-OH）转动振动,1738 cm^-1处出现酯基C=O的伸缩振动吸收峰,表明乙酰化已经成功接入。扫描电镜结果显示,未经乙酰化的蛋黄果多糖表面相对光滑平整,呈片状结构;乙酰化修饰多糖分子间交联增强,构象发生了变化,变为表面形状不规则,出现很多空隙且表面粗糙。3种乙酰化蛋黄果多糖中DHG-Ac2（3 mL醋酐）清除效果最好,在浓度1.0 mg/mL时,DPPH清除能力、ABTS自由基清除率、OH自由基清除率分别为91.37%、58.73%、56.36%,分别高于蛋黄果多糖10.0%、43.7%、25.3%。这是引入的乙酰基能活化多糖链中的异头碳,使多糖的供氢能力提升,继而提升乙酰化蛋黄果多糖的抗氧化作用。本研究为海南产蛋黄果多糖的深入开发与抗氧化应用提供了基础研究数据。     

7种黄檀属植物心材挥发油的成分分析及其抗菌活性

为了研究7种黄檀属（Dalbergia L.）植物心材的挥发性成分及其抗菌活性,采用水蒸气蒸馏法提取黄檀属植物心材的挥发性成分,气相色谱-质谱联用技术（GC-MS）对其化学成分进行分析;采用滤纸片琼脂扩散法测定挥发性成分的抗菌活性。结果表明,两粤黄檀检出9种成分,占总含量的98.93%;斜叶黄檀检出6种成分,占总含量的91.80%;交趾黄檀检出13种成分,占总含量的86.23%;海南黄檀检出9种成分,占总含量的94.86%;降香黄檀检出8种成分,占总含量的97.38%;东京黄檀检出8种成分,占总含量的97.72%;白沙黄檀检出23种成分,占总含量的79.45%。两粤黄檀和斜叶黄檀相对百分含量最大的成分为榄香素,分别为83.38%和73.03%;交趾黄檀中相对百分含量最大的成分为美迪紫檀素,为27.72%;海南黄檀中相对百分含量最大的成分为亚油酸,为42.80%;降香黄檀和东京黄檀中相对百分含量最大的成分为(7R,10S)-2,6,10-三甲基-7,10-环氧-2,11-十二碳-6-醇及其同分异构体,二者之和分别为60.37%和53.23%;白沙黄檀中已鉴定出且相对百分含量较大的成分为榄香素,为7.81%。黄檀属植物心材挥发性成分主要有苯丙素类、倍半萜类、黄酮类、脂肪酸类和甾体等,黄檀属植物心材的挥发性成分均对金黄色葡萄球菌具有抑制作用,部分挥发油对不同的农业病原菌具有一定的抑制作用。本研究为黄檀属植物的资源保护和开发利用提供了科学依据。     

膨爆预处理对三种菜籽油品质及挥发性风味成分的影响

本文以甘蓝型、白菜型和芥菜型三种油菜籽为原料，探究了油菜籽经过膨爆预处理后菜籽油的品质及挥发性风味成分的变化。研究结果表明，膨爆预处理后甘蓝型、白菜型和芥菜型三种菜籽油的酸值和过氧化值均显著增加（P＜0.05），分别增加了0.25、0.49、0.39 mg KOH/g和0.20、0.18、0.18 mmol/kg，均在国际食品法典规定的范围内；三种菜籽油的氧化诱导时间均显著增加（P＜0.05），分别增加了17.32、10.06和13.99 h。膨爆预处理对三种菜籽油的脂肪酸组成无显著影响。膨爆预处理后，甘蓝型、白菜型和芥菜型三种菜籽油中苯乙腈、3-甲基巴豆腈、5-己烯腈等含硫化合物含量、杂环类物质以及氧化挥发物的种类和含量均显著增加（P＜0.05），杂环类物质和氧化挥发物中分别是以吡嗪类和醛类物质为主。     

番石榴叶挥发油的抗菌性及优化提取研究

分别由酸疮痂链霉菌（Streptomyces acidiscabies, SA）、茄科雷尔氏菌（Ralstonia solanacearum, RS）和胡萝卜软腐欧文氏菌（Erwinia carotovora subsp. carotovora Borgey, ECCB）引起的植物疮痂病、青枯病、软腐病是农作物生产中常见多发的细菌病害。番石榴叶挥发油由多种活性物质组成，具有广谱抗微生物活性。本研究旨在提取并配置番石榴叶挥发油抗菌液，针对酸疮痂链霉菌、茄科雷尔氏菌、胡萝卜软腐欧文氏菌等3种病原菌进行挥发油的抗性研究，为农作物病害生物防治储备资源。采用添加锂盐结合微波辅助水蒸馏法提取番石榴叶挥发油，通过滤纸片扩散法和最小抑制浓度（MIC）评价了番石榴叶挥发油对3种供试菌株的抗菌效果，单因素结合响应面试验优化提取工艺，采用气相色谱-质谱联用技术（GC-MS）测定番石榴叶挥发油的化学成分。结果表明：番石榴叶挥发油对酸疮痂链霉菌、茄科雷尔氏菌、胡萝卜软腐欧文氏菌均表现出良好的抑制效果，抑菌圈直径范围为20.57～23.24 mm，抑菌率均达到60%以上，MIC值分别为3.13、1.56、3.13...     

Novel seed oil types of Ethiopian mustard with high levels of polyunsaturated fatty acids

Oils rich in polyunsaturated fatty acids linoleic acid and linolenic acid have important industrial applications, both as drying oils in the manufacture of paints and coatings as well as in formulation of pharmaceuticals and nutraceuticals. However, no oil types with high levels of polyunsaturation have been developed so far in Brassica oilseed crops. The objective of the present research was to select for high levels of linoleic acid and linolenic acid in Ethiopian mustard (Brassica carinata A. Braun). Selection started from the F₃ (S₀) seed generation of crosses involving the high oleic acid, high erucic acid line N2-3591, the low linolenic, high erucic acid line HF-186, and the zero erucic acid line 25X-1. The analysis of individual S₀ seeds showed ranges of variation with maximum levels of 68.9% linoleic acid and 36.4% linolenic acid. Selection for increased levels of linoleic acid resulted in a S_1:2 high linoleic acid line BC-HL that showed average linoleic acid contents of 62.5%, 58.3%, and 59.6%, respectively in three contrasting environments, compared to 47.8%, 45.8%, and 52.1%, respectively in a high linoleic acid check line. Selection for increased levels of linolenic acid resulted in a S_1:2 high linolenic acid line BC-HLN that showed average linolenic acid contents of 27.1%, 25.8%, and 26.3%, respectively in the mentioned environments, compared to 23.9%, 21.2%, and 19.4%, respectively in a high linolenic acid check line. Both lines developed in the present research possess novel fatty acid profiles not available so far in Brassica oilseed crops and they may contribute to broaden the potential of Brassica oils for industrial applications.     

Comparative advantages of chemical compositions of specific edible vegetable oils

As important supplementary to major edible oils, comparative chemical advantages of minor edible oils decide their development and usage. In this study, chemical composition of 13 kinds of specific edible vegetable oils were investigated. The comparative advantages of chemical compositions of these edible oils were obtained as follows: (1) camellia, tiger nut and almond oil were rich in oleic acid, the contents of which accounted for 79.43%, 69.16% and 66.26%, respectively; (2) safflower oil contained the highest content of linoleic acid (76.69%), followed by grape seed (66.85%) and walnut oil (57.30%); (3) perilla seed, siritch, peony seed and herbaceous peony seed oil were rich in α-linolenic acid (59.61%, 43.74%, 40.83% and 30.84%, respectively); (4) the total phytosterol contents of these oils ranged from 91.46 mg/100 ​g (camellia oil) to 506.46 mg/100 ​g (siritch oil); and (5) The best source of tocopherols was sacha inchi oil (122.74 mg/100 ​g), followed by perilla seed oil (55.89 mg/100 ​g), peony seed oil (53.73 mg/100 ​g) and herbaceous peony seed oil (47.17 mg/100 ​g). The comparative advantages of these specific edible oils indicated that they possess the high potential nutritional values and health care functions.     

白千层精油的化学成分与抑菌活性研究

研究白千层精油的化学成分及其对植物病原真菌的抑菌活性,为环境友好型农药的研发及白千层的综合应用提供理论依据。采用气相色谱-质谱（GC-MS）联用技术分析了白千层精油的化学成分,并用菌丝生长速率法测定了白千层精油对4种植物病原真菌的抑菌活性。从白千层精油中分离鉴定出74种化学成分,占总含量的97.28%,其主要化学成分是左旋-α-蒎烯（2.07%）、β-月桂烯（1.05%）、1,8-桉叶素（67.29%）、萜品烯（2.52%）、芳樟醇（2.36%）、α-松油醇（7.93%）和(+)-g-桉叶油醇（1.26%）等。进一步研究表明,白千层精油在5.0~10.0 μL/mL浓度范围对立枯丝核菌菌丝生长抑制率为100%;处理2 d时,白千层精油在2.5~10.0 μL/mL浓度下对小孢拟盘多毛孢菌、水稻稻瘟病菌和香蕉枯萎病菌的菌丝生长抑制率达71.59%以上,其抑菌作用均随着处理浓度的增加而增强,随着白千层精油处理时间的延长,对3种植物病原菌表现出较好的持效性。白千层精油对立枯丝核菌、小孢拟盘多毛孢菌、水稻稻瘟病菌和香蕉枯萎病菌均具有较强的抑菌活性,在农用抗菌剂应用中有较好的应用潜力。     

Proximate composition, extraction, characterization and comparative assessment of coconut (Cocos nucifera) and melon (Colocynthis citrullus) seeds and seed oils

Proximate composition, extraction, characterization and comparative assessment of Cocos nucifera and Colocynthis citrullus seeds and seed oils were evaluated in this work using standard analytical techniques. The results showed the percentage (%) moisture, crude fibre, ash, crude protein, lipids and total carbohydrate contents of the seeds as 7.51 and 4.27, 7.70 and 5.51, 1.02 and 2.94, 10.57 and 11.67, 47.80 and 50.42 and 32.84 and 29.47 while the calorific values were 553.99 and 567.32 Kcal/100 g for C. nucifera and C. citrullus, respectively. The two seed oils were odourless and at room temperature (30 degrees C) liquids, with a pale yellow to yellowish colouration. Lipid indices of the seed oils indicated the Acid Values (AV) as 2.06-6.36 mg NaOH g(-1) and 2.99-6.17 mg NaOH g(-1), Free Fatty Acids (FFA) as 1.03-3.18 and 1.49-3.09%, Saponification Values (SV) as 252.44-257.59 and 196.82-201.03 mg KOH g(-1), Iodine Values (IV) as 9.73-10.99 and 110.93-111.46 mg of I2 g(-1) of oil and Peroxide Values (PV) as 0.21-0.21 and 1.53-2.72 mg O2 kg(-1) for soxhlet-mechanical extracted C. nucifera and C. citrullus seed oils, respectively. The studied characteristics of the oil extracts in most cases compared favourably with most conventional vegetable oils sold in the Nigeria markets; however, there were some observed levels of significant differences in the values at p < or = 0.05. These results suggest that the seeds examined may be nutritionally potent and also viable sources of seed oils judging by their oil yield. The data also showed that the seed oils were edible inferring from their low AV and their corresponding low FFA contents. Industrially, the results revealed the seed oils to have great potentials in soap manufacturing industries because of their high SV. They were also shown to be non-drying due to their low IV which also suggested that the oils contain few unsaturated bonds and therefore have low susceptibility to oxidative rancidity and deterioration as confirmed by their low PV which also serves as indicators of the presence or high levels of anti-oxidants in the oils.     

Composition and physical properties of cress (Lepidium sativum L.) and field pennycress (Thlaspi arvense L.) oils

The fatty acid profiles and tocopherol and phytosterol contents of crude oils of cress (Lepidium sativum L.) and field pennycress (Thlaspi arvense L.) are reported, along with yields from the corresponding seeds. The physical properties of these oils were also determined, which included oxidative stability, kinematic viscosity, viscosity index, low temperature fluidity, specific gravity, acid value, lubricity, and iodine value. The oil content of dried cress and field pennycress seeds was 22.7 and 29.0 wt%, respectively. The primary fatty acids found in cress oil were oleic (30.6 wt%) and linolenic acids (29.3 wt%), whereas field pennycress oil was principally composed of erucic (32.8 wt%) and linoleic (22.4 wt%) acids. Cress oil contained high concentrations of γ- (1422 ppm) and δ- (356 ppm) tocopherols, whereas α-tocopherol (714 ppm) was the primary tocopherol discovered in field pennycress oil. The overall tocopherol concentrations of cress and field pennycress oils were 1799 and 851 ppm, respectively. The primary phytosterols elucidated in cress and field pennycress oils were sitosterol and campesterol, with avenasterol also present in significant quantity in cress oil. The total phytosterol concentration in cress oil (14.41 mg/g) was greater than that in field pennycress (8.55 mg/g) oil. Field pennycress oil exhibited excellent low temperature fluidity, whereas cress oil was more stable to oxidation and over a range of temperatures displayed lower kinematic viscosities as well as a higher viscosity index. The acid and iodine values of field pennycress oil were lower than those for cress oil, but both oils had excellent lubrication properties.     

顶空固相微萃取-气相色谱-质谱联用法分析鸡骨香叶挥发性成分

采用顶空固相微萃取-气相色谱-质谱联用法（HS-SPME-GC-MS）研究了鸡骨香叶的挥发性成分,在优化HS-SPME萃取条件的基础上,通过GC-MS从鸡骨香叶中鉴定了54个主要组分,并采用峰面积归一化法测定了各成分的相对含量,主要为反-2-己烯醛（38.62%）、芳樟醇（11.96%）、石竹烯（11.10%）、反-橙花叔醇（6.78%）和β-榄香烯（3.67%）等。其中,醛类化合物占40.37%,烯萜类化合物占36.03%,醇类化合物占21.90%,以及少量的酮类和酯类化合物。     

Seed oils rich in linolenic acid as renewable feedstock for environment-friendly crosslinkers in powder coatings

In the work described, seed oils rich in linolenic acid were used for the synthesis of aliphatic oxiranes. The oils studied were linseed (Linum usitatissimum) oil, Canadian linseed oil and the oil of Lallemantia iberica. The oils contained 54.1, 60.2 and 68.0% of linolenic acid, respectively, and showed high theoretical iodine values of 211, 226 and 236 g/hg. Unsaturations in the oils were used to introduce epoxides by epoxidation with in situ generated peroxyacetic acid. The epoxidized oils, showing high percentages of oxirane oxygen (9.4, 10.0 and 10.7%), were applied as crosslinkers in powder-coating formulations. The major advantage of these types of crosslinkers is that they are neither toxic nor mutagenic, in contrast with the widely applied synthetic triglycidyl isocyanurate (TGIC) crosslinkers. However, two potential problems exist when aliphatic oxiranes are compared with conventional TGIC systems. A decrease in glass transition temperature (T_g) of the powder formulation and a higher degree of yellowing of the coating are often observed. In this paper the effects of using oils containing high linolenic acid contents on the yellowing of the coating and the T_g of the powder, are studied. It appeared that aliphatic oxiranes are suitable as environment-friendly crosslinkers in powder-coating systems.