The use of immobilized Candida antarctica lipase for simultaneous supercritical fluid extraction and in-situ methanolysis of cis-vaccenic acid in milkweed seeds

cis-Vaccenate was determined in milkweed (Ascelpias) seed employing supercritical fluid extraction (SFE) with in-situ enzymatic methanolysis. Candida antarctica lipase type B immobilized onto two different types of carrier materials—a hydrophobic polymer (Novozyme 435) and a silica-based material (NovoSample 40013)—was investigated. Several SFE parameters were investigated to find the optimal conditions, including extraction time, temperature, methanol concentration, and water level. It was shown that 90 min of dynamic extraction/reaction time was required, and that the optimal methanol and water concentrations differed for the two enzyme preparations studied. Overall, Novozyme 435 demonstrated the fastest reaction kinetics and consistently gave the highest vaccenate yields. The optimized methodology was applied on 15 species of milkweed seeds, giving an average recovery of 105±7% when compared to results obtained using a conventional methodology. The average relative standard deviations were 8% for the enzyme-based method and 4% for the reference method. The proposed methodology was faster, was less laborious, and consumed less organic solvent than the reference method. Hence, SFE with in-situ enzymatic methanolysis is a promising methodology for the analysis of FA in oilseeds.     

Practical nuclear magnetic resonance analysis of liquid oil in oilseeds: I factors affecting peak width

If proton nuclear magnetic resonance (NMR) spectra of single seeds can be improved, a rapid, low-cost method of screening seeds for oil composition could be developed for use as a selection tool in plant breeding. NMR spectroscopy was performed on single seeds of borage, flax, and canola to evaluate methods for improving spectra quality (narrowing peak widths and increasing signal-to-noise ratio) to a degree necessary to measure differences among seeds in a breeding program. Immersion of seeds in a variety of solvents, including deuterated chloroform, deuterated acetone, deuterated dimethyl sulfoxide (DMSO) and completely fluorinated hydrocarbons (FC-77), narrowed peaks obtained from seeds when compared with spectra from seeds analyzed in the absence of a solvent. Deuterated chloroform and FC-77 were free of interfering solvent proton peaks while deuterated acetone and deuterated DMSO contributed interfering peaks. The spectra of dehulled seeds had narrower peak widths than did seeds with hulls. Treatments that decreased seed oil viscosity failed to substantially narrow spectra peak widths of seeds. High magnetic field strength did not improve the spectral quality of seeds, as peak widths increased with field strength. Conversely, low field strength limited resolution of oil spectra. Although the 300 MHz spectrum of vegetable oil had greater resolution (narrower peaks) than the 60 MHz spectrum, spectra of seeds produced at 60 MHz had superior resolution to 300 MHz spectra.     

Low risks of toxicity from boron fertiliser in oilseed rape–rice rotations in southeast China

Yields in intensive rice (Oryza sativa L.) -based rotations in Asia are stagnating or declining because of decreasing nutrient availability and depletion of soil nutrient reserves. In the rape (Brassica napus L.)–rice–rice cropping rotation of southeast China, where boron (B) deficiency is widespread and B fertiliser is needed to correct it, our objective was to evaluate the risks of fertiliser-induced B toxicity in oilseed rape and in rice. Response of oilseed rape to B fertiliser application at rates up to 6.6 kg B ha-1 was studied in seven field experiments on three contrasting soils of Zhejiang province, alluvial, red and blue-purple soils. The effects of up to 3.3 kg B ha-1 in 1 year, 6.6 kg B ha-1 in 2 years or 9.9 kg B ha-1 in 3 years were studied on oilseed rape and the one or two rice crops grown immediately after rape in each annual crop rotation. Soils varied in initial hot CaCl2-extractable B in the 0–15-cm layer from 0.24 to 0.99 mg kg-1. At the stem elongation stage of oilseed rape, 3.3 kg B ha-1 depressed shoot dry matter on soils with low clay and organic matter content. However, the subsequent effects of high fertiliser B on seed yield were minimal even at 6.6 kg B ha-1. Moreover, the application of a total of 6.6 or 9.9 kg B ha-1 as successive annual applications of 3.3 kg B ha-1 to oilseed rape generally had no negative effect on seed yield of oilseed rape. The single exception was on a sandy alluvial soil where a total of 6.6 kg B ha-1 in 2 years slightly depressed seed yield of oilseed rape. Grain yields of rice crops grown in rotation after oilseed rape were unaffected by B applications up to 6.6 kg ha-1. The minimal effects of a total of 6.6 kg B ha-1 applied over 2 years on seed yield were consistent with the modest increase in hot CaCl2-extractable B levels. It is concluded that there is limited risk of B toxicity from the use of borax fertiliser at up to 4–8 times recommended rates in rape–rice cropping rotations in southeast China. The low risk of B toxicity can be attributed to the relatively high B removal in harvested seed, grain and stubble, the redistribution of fertiliser B by leaching in the 0–60 cm layer and to B sorption.     

油料冷态压榨过程中油脂流速模型

油料直筒式压榨制油时,始终与榨筒相互作用,同时受到轴向挤压和侧向限制产生破裂,直至其细胞中的油脂逐渐被挤压出来,油料被压实形成饼。针对该制油过程,通过简化假设建立了一维压榨模型,并对油料微元进行受力分析;利用固结理论,分析了油料高度及压榨系数对孔隙流体压力的影响,建立了压榨过程中流体流速模型。结果表明:压榨过程中同一时刻的流速取决于保压压力σ_0、压缩系数α_v和压榨系数C_v;同时,一定范围内保压时间越长,收集的油脂总量越多。     

胺苯磺隆作用特性及其应用

作者自１９９１～１９９７年对油菜田超高效除草剂胺苯磺隆进行了大量的室内和田间试验研究。说明了胺苯磺隆在各种不同条件下的除草效果、安全性、残留以及对后茬作物的影响。并对胺苯磺隆的应用技术以及应用中出现的问题进行了分析。通过对胺苯磺隆的应用研究,作者还对长持效除草剂的试验推广和科学管理进行了探讨。     

Effects of low-vacuum helium cold plasma treatment on seed germination,plant growth and yield of oilseed rape

The effects of low-vacuum helium cold plasma treatment on the seed germination,plant growth and yield of oilseed rape(Brassica napus L.cv.Zhongshuang 9) were investigated.Seeds were exposed to low-vacuum helium cold plasma ranging from 0–120 W for 15 s.Cold plasma increased the germination,plant growth and yield of oilseed rape,and the treatment of 100 W provided the best result.The germination rate,germination and vigor indices,and uniformity of emergence were improved by cold plasma treatment.Cold plasma raised the relative conductivity and water uptake,and reduced the apparent contact angle.The characteristics of plant growth,including plant height,stem diameter,dry weights of shoot and root at the seedling,bolting and flowering stages were increased by the cold plasma treatment.Yield components,including pod numbers per plant and 1000 seed weights were increased by the cold plasma treatment.Furthermore,the yield per plant increased by 28.20%.These results suggest that cold plasma treatment has the potential to improve the yield of oilseed rape through the enhancement of permeability,wettability and capacity of water uptake of the seeds,seed germination and plant growth.     

我国油菜生产布局时空演变及影响因素分析

为进一步优化我国油菜生产布局,基于生产集中度指数、生产规模指数、空间重心分析、产地集中度系数等数据模型对21世纪以来我国油菜生产布局时空演变及影响因素进行分析。结果表明：进入21世纪以来,我国油菜主产省基本无变化,但受各省不同产业定位的影响,四川、湖南、重庆、云南油菜生产集中度指数逐年上升,安徽、江苏、浙江逐年下降;油菜产业扶持政策的陆续实施推动南方地区油菜生产规模自2007年逐渐上升,北方对应下降,东、中、西三部及七大产区不同的区位特性导致国内油菜生产在空间布局上总体呈现“东减、中稳、西移”的特征;油菜籽产量及油菜播种面积空间重心则由中部逐渐向西南迁移;油菜产地集中度系数总体呈波动上升的趋势,即油菜生产趋向于主产地。受自然环境、产业模式、政策扶持、科技创新等综合影响,我国油菜产业的区位优势更加明显,空间布局日益优化。建议通过长江流域油菜优势产业带建设、油脂加工企业政策扶持、北方盐碱地开发、南方冬闲田扩种及油菜多功能开发利用等措施进一步提升我国油菜产业国际竞争力。     

突飞猛进的中国油脂工业

中国粮油学会油脂专业分会成立于1985年10月5日,学会成立20年来,中国的油脂工业得到了突飞猛进的发展.从我国油脂、油料生产与消费的快速增长、油脂工业的总体发展水平、市场上琳琅满目的食用油脂产品、大型化油厂建设、油料资源综合利用、油脂机械装备水平、油脂科研和教育等7个方面分别对学会成立20年来,在促进我国油脂科技进步、油脂工业整体水平的提高方面所做的贡献进行了全面而客观的回顾,并对2004年油脂工业的发展特点进行了分析,展望了我国油脂工业的美好前景.     

甘蓝型油菜表皮特异硫蛋白(ESP)的序列分析及其诱导表达

为了揭示植物激素及环境胁迫对甘蓝型油菜(Brassica napus)表皮特异硫蛋白(ESP)表达的影响,以中双9号品种为材料,采用同源克隆法获得一编码甘蓝型油菜表皮特异硫蛋白(BnESP)的cDNA,序列分析表明其编码蛋白BnESP含有343个氨基酸,与青花菜(Brassica napus)ESP有99%的相似性,与拟南芥腈特异性蛋白、类黑芥子酶结合蛋白、茉莉酸诱导蛋白有较高的同源性。荧光定量RT-PCR分析显示,甲基茉莉酸和机械伤害快速激活BnESP的表达,苯丙噻重氮和核盘菌(Sclerotinia sclerotiorum)抑制其表达。研究证明BnESP是茉莉酸诱导蛋白,可能在水杨酸和茉莉酸信号的互作及油菜对S. sclerotiorum的反应网络中起作用。