A rapid in situ transesterification process of sunflower oil with methanol assisted by diethoxymethane (DEM) is described in this article. DEM served as both extraction solvent and reaction promoter in the process. The effects of moisture content of sunflower seeds, catalyst category, molar ratio of catalyst/oil, molar ratio of methanol/oil, molar ratio of DEM/oil, reaction time, reaction temperature, and agitation speed on the in situ transesterification were investigated. The most important factors which influenced the crude biodiesel yield, free fatty acid (FFA) content, and fatty acid methyl ester (FAME) purity were the molar ratio of DEM/oil, molar ratio of catalyst/oil, and molar ratio of catalyst/oil, respectively. An empirical model of the rapid in situ transesterification process was established and used to determine the optimal reaction conditions. When the in situ transesterification was carried out at the molar ratio of catalyst/oil of 0.5:1, the molar ratio of methanol/oil of 101.39:1, the molar ratio of DEM/oil of 57.85:1, the agitation speed of 150 rpm, and reaction temperature of 20 °C, a product containing 97.7% FAME and 0.74% FFA was obtained within 13 min.

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At appropriate concentrations, polyamines promoted the callus growth and echinacoside content of Cistanche deserticola while Ag + increased the content of echinacoside and acteoside. In a 20-day culture period, when putrescine (25 lM) and Ag + (10 lM) were added on day 8 and day 16, respectively, the echinacoside production (1.7 g l -1 ) and acteoside production (0.4 g l -1 ) reached the maximum, which were 1.4-fold and 1.5-fold of those in single putrescine treatment, 1.6-fold and 1.4-fold of those in single Ag + treatment, respectively. Exogenous putrescine enhanced cell viability and antioxidant enzyme activity markedly, so increased the final biomass. Ag + addition increased H 2 O 2 content and phenylalanine ammonia-lyase activity significantly which led to higher echinacoside and acteoside contents.