ABSTRACT
This article investigated the applicability of the near infrared spectroscopy (NIR) technology, combined with the least squares support vector machines (LS SVM) used for the quality monitoring of medicated leaven fermentation. First, near infrared spectra of 67 medicated leaven samples were obtained by near infrared spectroscopy system in the wavelength range of 400 2 500 nm, and then the protease and amylase activity were measured by Folin phenol method and DNS method. Thereafter, the LS SVM was employed to calibrate models. The Rc and Rp of protease in near infrared model were 0.975 and 0.938, respectively; The RMSEC and RMSEP were 5.297 and 9.795, respectively. The Rc and Rp of amylase in near infrared model were 0.987 and 0.973, respectively; The RMSEC and RMSEP were 7.215 and 6.864, respectively. This model has good prediction ability and is suitable for quality monitoring in medicated leaven fermentation process. The research achievement could lay a certain foundation for the near infrared spectral analysis technology applied in the field of traditional fermentation processing.
ABSTRACT
This study was aimed to optimize bio-solid bidirectional fermentation conditions of Trametes robiniophia Murr. for rhubarb. Sulphuric acid-phenol colorimetry, magnesium-methanol colorimetry, and HPLC were used in the content determination of polysaccharide, total anthraquinone, and 4 free anthraquinones. The drying rate and con-sumption rate were combined as indicators for the optimization of technical parameters such as medicinal dosage, temperature and amount of water. The results showed that when using 500 mL conical flask, the best fermentation conditions were medicinal dosage of 10 g, the temperature of 34℃, adding water of 120%. It was concluded that bidirectional fermentation of rhubarb increased the content of free anthraquinones. Among them, the content of chrysophanol with anti-oxidation effect increased significantly. The decreasing of combined anthraquinone can relieve the severe laxative effect of rhubarb.