芥菜型油菜重组自交系群体重要品质性状的遗传分析

本研究调查了一个包含139个芥菜型油菜重组自交系群体的脂肪酸(硬脂酸、油酸、亚油酸、亚麻酸、芥酸)和硫甙含量,相关性分析显示,芥酸与其它脂肪酸间均呈极显著负相关,而除芥酸外的其它脂肪酸间则呈极显著正相关.品质性状均表现出较高广义遗传力,其中芥酸和硫甙的遗传力超过90％,硬脂酸和亚油酸的遗传力在80％～90％之间,而亚油酸和亚麻酸的遗传力在70％～80％之间.主成分分析获得2个分别能解释64.9％和16.4％的变异因子,散点图将全部139个株系分成群Ⅰ、群Ⅱ和4个散落的株系,聚类分析对于此群体品质性状的遗传和特异材料的筛选有一定参考价值.     

茎瘤芥的芥子油苷组分及含量的品种间差异

 为了探讨茎瘤芥（Brassica juncea var. tumida Tsen et Lee）芥子油苷组分和含量在品种和器官间的差异,以4个品种为材料,在现蕾期分根、瘤状茎、功能叶和花蕾取样,用高效液相色谱法（HPLC）测定了芥子油苷组分及其含量。在不同品种和器官中均检测到9种芥子油苷,其中脂肪族芥子油苷4种（2–丙烯基芥子油苷、3–丁烯基芥子油苷、1–甲基丙基芥子油苷和1–甲基丁基芥子油苷）,吲哚族芥子油苷4种（4–羟基吲哚–3–甲基芥子油苷、吲哚–3–甲基芥子油苷、4–甲氧吲哚–3–甲基芥子油苷和1–甲氧吲哚–3–甲基芥子油苷）,芳香族芥子油苷1种（2–苯基乙基芥子油苷）。4个品种根、瘤状茎、功能叶、花蕾中总芥子油苷含量依次为13.632 ~ 20.155、25.916 ~ 36.487、63.715 ~ 96.259和89.764 ~ 129.763 μmol · g^-1 DW;根中芥子油苷以2–苯基乙基芥子油苷和2–丙烯基芥子油苷含量为主,分别占根中芥子油苷总量的34.99% ~ 61.87%和13.54% ~ 47.53%;瘤状茎、功能叶和花蕾中均以2–丙烯基芥子油苷为主,分别占瘤状茎、功能叶和花蕾总芥子油苷含量的81.38% ~ 93.04%、85.45% ~ 95.99%和88.60% ~ 95.18%。茎瘤芥根、瘤状茎、功能叶和花蕾中多数芥子油苷组分的含量在品种间存在显著或极显著差异。     

大白菜中硫代葡萄糖苷的鉴定及含量分析

 以129份大白菜 [Brassca campestris L.ssp.pekinensis（Lour.）Olsson] DH系为材料,采用HPLC法,对不同季节生长的大白菜叶片中硫苷的组分和含量进行了研究。在129份材料中均检测到8种硫苷成分,包含3种脂肪族硫苷,4种吲哚族硫苷和1种芳香族硫苷。主成分分析表明脂肪族硫苷3–丁烯基硫苷（NAP）、4–戊烯基硫苷（GBN）和2–羟基–3–丁烯基硫苷（PRO）是大白菜硫苷的主要组分,占总硫苷含量的60%。筛选出了6份高硫苷含量的材料。联合方差分析结果表明,脂肪族硫苷NAP、GBN和PRO在不同品种间差异极显著;某些吲哚族硫苷受环境影响较大,在不同的季节间差异显著;芳香族硫苷2–苯乙基硫苷（NAS）的含量在季节和季节 × 品种间差异显著。不同硫苷间的积累存在相互影响, NAP与GBN、NAP和GBN与总硫苷在两个年份中均呈极显著正相关。     

菜籽饼硫代葡萄糖苷降解产物对猪、鸡、鸭甲状腺的影响

饲喂含20％菜籽饼饲粮(硫代葡萄糖苷的含量为0.252％)引起猪、鸡和鸭的甲状腺肿大和甲状腺滤泡腔增大及滤泡上皮细胞轻度增生。三种动物的甲状腺虽都有明显的代偿性反应,但代偿能力和反应形式各不相同:猪血清三碘甲状腺原氨酸(T_3)水平升高137％(P<0.01),甲状腺素(T_4)水平则降低39％(P<0.01),甲状腺肿大118％(P<0.01),而鸡血清T_3水平与对照组无明显差异(P>0.05),T_4则高于对照组25％(P<0.05),甲状腺肿大49％(P<0.01);鸭血清T_3和T_4水平均与对照组基本一致(P>0.05),但甲状腺肿大192％(P<0.01)。     

Selenium Accumulation and Biochemical Composition of Brassica Grains Grown in Selenate- or Selenite-Treated Alkaline Sandy Loam Soil

In a greenhouse experiment, Brassica plants were grown in an alkaline sandy loam soil treated with different levels of selenate selenium (Se) or selenite Se ranging from 0 to 4 mg Se kg^?1. Plants grown in Se-treated soil were stressed at an early stage of pod setting and produced fewer pods per plant. Selenium accumulation increased by 2- to 35-fold in shoots, 3- to 19-fold in roots, and 2- to 57-fold in grains. Selenium accumulation in grains resulted in significant increases in contents of reducing sugars, starch, glucosinolate, and free and sulfur-containing amino acids and a decrease in lipid content. Selenium accumulation significantly increased the proportions of different lipid classes such as glycolipids, sterols, and free fatty acids whereas triacylglyceride content showed the reverse trend. Oil extracted from Brassica grains grown in the seleniferous region contained Se within safe limits and thus is safe for human consumption.     

萝卜芥子油苷组分及含量的分析

 采用HPLC-MS联用分析法,对‘心里美’萝卜（Raphanus sativus L.）芽、叶片以及肉质根中芥子油苷的组分与含量进行了鉴定和分析。结果表明,萝卜芽、叶片和根的芥子油苷组分相同,均检测出8种芥子油苷,其中脂肪族芥子油苷5种（4-甲基亚磺酰基-3-丁烯基芥子油苷、2-羟基-3-丁烯基芥子油苷、乙基芥子油苷、4-甲硫基-3-丁烯基芥子油苷和6-庚烯基芥子油苷）,吲哚族芥子油苷3种（1-甲氧吲哚基-3-甲基芥子油苷、吲哚基-3-甲基芥子油苷和4-羟基吲哚基-3-甲基芥子油苷）。芥子油苷含量在萝卜芽、叶片和肉质根中差异很大,肉质根中芥子油苷的总含量高于萝卜芽和叶片。在肉质根和芽中,4-甲硫基-3-丁烯基芥子油苷是主要的芥子油苷,分别占芥子油苷总含量的75.5%和71.5%;而在叶片中,吲哚基-3-甲基芥子油苷是主要芥子油苷,占芥子油苷总含量的57.1%。     

Factors Influencing Glucoraphanin and Sulforaphane Formation in Brassica Plants: AReview

Sulforaphane is a type of sulfur-containing isothiocyanates hydrolyzed from glucosinolates by myrosinase found in Brassica plants. Sulforaphane is a naturally occurring inducer of phase II enzymes in human and animal bodies to detoxify cancer-causing chemicals. Glucoraphanin is the precursor of sulforaphane and its content is greatly influenced by plant species and genotype, plant organs, pre-harvest factors, and post-harvest processing, thus sulforaphane formation is also directly influenced. Here, we review the formation mechanism of sulforaphane and the factors influencing sulforaphane formation. In the end, the future directions are also discussed.     

拟南芥硫代葡糖苷酶基因TGG1的克隆、表达和酶学特性

本研究克隆拟南芥硫代葡糖苷酶基因TGG1,利用毕氏酵母表达。重组蛋白用镍亲和柱纯化,获得高纯度芥子酶。重组蛋白分子量78 kD,与天然TGG1分子量接近,为糖基化蛋白。TGG1信号肽在酵母中具有分泌功能,约25%芥子酶分泌到培养基中。TGG1重组蛋白具有广泛的pH适应性,最适反应温度40℃左右。其活性被低浓度维生素C激活,被高浓度维生素C抑制。用Hanes plot方法计算TGG1重组蛋白以Sinigrin为底物时,Km为65μmol/L,最大反应速率Vmax=3.28μmol.min-1.mg-1。