Experiments of ultrasonic-associated extraction and hot water extraction of water soluble polysaccharides from defatted Korean pine （Pinus koraiensis） were conducted in Northeast Forestry University, Harbin, China. ...
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Experiments of ultrasonic-associated extraction and hot water extraction of water soluble polysaccharides from defatted Korean pine （Pinus koraiensis） were conducted in Northeast Forestry University, Harbin, China. The factors affecting extraction yield and content, such as extracting temperature, extracting time, the ratio of water to defatted kernel and concentration of ethanol were analyzed under specific condition. The optimal extracting parameters for ultrasound-associated extraction were determined as the ultrasonic temperature 70℃, the ratio of defatted kernel to water 1：20, the extracting time 40 min, and ethanol concentration 80%. Under such extraction conditions, the yield of water soluble polysaccharide was 3.65% and the average content of polysaccharide was 45.38% in the raw polysaccharides which gained in the experiment. Both extraction yield and content of polysaccharides extracted with ultrasound-associated extraction were higher than that with hot water extraction. The study demonstrates that ultrasound is a reliable and extremely effective tool for the fast extraction of water soluble polysaccharide of Korean pine kernel.
UGPase gene related with wood cellulose synthesis was transferred into C. acuminata using the method of Agrobacte- rium-mediated genetic transformation, and an efficient transformation system was developed for C. acum...
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UGPase gene related with wood cellulose synthesis was transferred into C. acuminata using the method of Agrobacte- rium-mediated genetic transformation, and an efficient transformation system was developed for C. acuminata on the basis of evaluations of several factors affecting Agrobacterium-mediated DNA transfer rate. The highest transformation rate was achieved when pre-cultttred leaf explants were infected with an Agrobacterium culture corresponding to OD600 （0.5） for 10 min, and cultured on explant regeneration medium for three days. The results of Southern hybridization showed that genomic DNA of the kanamycin-resistant shoots to an UGPase gene probe substantiated the integration of the transgene. Transformation efficiency （6%） was achieved under the optimized transformation procedure, This system should facilitate the introduction of important useful genes into C, acuminata.
A study was conducted to investigate the effects of high temperature on variations of alkaloid metabolism in C. roseus seedlings in Key Laboratory of Forest Plant Ecology, Northeast Forestry University, Heilongiang, C...
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A study was conducted to investigate the effects of high temperature on variations of alkaloid metabolism in C. roseus seedlings in Key Laboratory of Forest Plant Ecology, Northeast Forestry University, Heilongiang, China. 60-day-old C. roseus seedlings with 3-4 pairs of leaves were incubated in chambers with temperature of 30℃ and 40℃for short-term heat shock experiment and 20℃, 25℃ and 35℃ for long-term experiment. The contents of vindoline, catharanthine, vinblastine and vincristine in C. roseus leaves and root were checked at different temperatures in short term （1-6 h） and long term （1-16 d）. Results showed that under short-term heat shock, the contents of vindoline, catharanthine and vinblastine in leaves of the seedlings were higher at 40℃ than at 30℃, but after 6 h treatment, the contents of vindoline and catharanthine under the two temperatures came to the same level. Catharanthine was exclusively distributed in C. roseus roots and its content was increased by 40% after two hours incubation at 40℃, while increased slowly at 30℃ incubation and reached the highest value at 6 h. In the Long-term experiment, concentrations of monomeric alkaloids catharanthine and vindoline were higher at 20℃ than at 25℃ and had a sharp increase under the condition of 35℃. While for dimeric alkaloid, it showed that the higher the temperature, the earlier the peak value of vinblastine content appears. Vincristine had a continuous enhancement and attained 0.027 mg.g^-1 at 16th day under 35℃ condition which was higher than those in the other conditions. It was concluded that high temperature could promote the accumulation of different alkaloids in C. roseus and the accumulation characteristic is highly related to treatment time.
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