芦笋-杏鲍菇发酵型饮料制备与组分检测

为了提升芦笋的利用价值,以芦笋作为液体培养基,杏鲍菇作为菌种,研究芦笋-杏鲍菇发酵型饮料制备工艺,采用单因素试验和响应面法确定最佳稳定剂配比和调味剂含量.采用水提醇沉法提取发酵型饮料中的多糖,并用苯酚-硫酸法测定其总多糖含量,最后采用高效液相色谱法检测饮料中营养成分.结果显示:经单因素和正交试验得出最佳稳定剂添加量为黄...     

Clonal propagation of mulberry (Morus indica L. cultivar M-5) through in vitro culture of nodal explants

A high frequency of sprouting (80.0%) and shoot differentiation was observed in the primary cultures of nodal explants of Morus indica L. cultivar M-5 on MS medium supplemented with 2,4-D (0.3 mg/l). In vitro proliferated shoots were multiplied rapidly by culture of shoot tips on MS medium with BAP (0.5 and 1.0 mg/l) which produced the greatest multiple shoot formation. Multiplication was also achieved by culture of shoot tips on MS medium with BAP (4.0 mg/l) and GA₃ (0.05 mg/l) which facilitated the elongation of shoots followed by sprouting of axillary buds of in vitro grown shoots. A high frequency of rooting (86.7%) with development of healthy roots was observed from shoots cultured on medium with 2,4-D (1.0 mg/l). Plants with well developed roots were transferred to soil with a survival frequency of 80%.     

Efficient production of transgenic plants using the bar gene for herbicide resistance in sweetpotato

Efficient production of transgenic sweetpotato (Ipomoea batatas (L.) Lam.) plants using the bar gene for herbicide resistance was achieved through the use of embryogenic suspension cultures and Agrobacterium tumefaciens-mediated transformation. Cell aggregates from embryogenic suspension cultures of sweetpotato cv. Lizixiang were cocultivated with A. tumefaciens strain EHA 105 harboring a binary vector pCAMBIA3300 with the bar gene and uidA gene. Selection culture was conducted using 0.5 mg/l PPT. A total of 1431 plants were produced from the inoculated 870 cell aggregates via somatic embryogenesis. GUS assay and PCR analysis of the regenerated plants randomly sampled showed that 86.5% of the regenerated plants were transgenic plants. Stable integration of the bar gene into the genome of transgenic plants was confirmed by Southern blot analysis and transgene expression was demonstrated by Northern blot analysis. The copy number of integrated bar gene ranged from 1 to 3. Transgenic plants exhibited functional expression of the bar gene by in vivo assay for herbicide resistance. This study also provides a simple and efficient transformation system of sweetpotato based on the use of bar gene as a selectable marker gene, which can be combined with other agronomically important genes for the improvement of sweetpotato.