Studies On The Chemical Constituents And The Processing Procedures Of Malt

The germinated ripe fruits of Hordeum vulgare L. (family Gramineae) were called malt or germinated barley. Malt has been used for promoting digestion and inducing lactation in traditional Chinese medicine. Raw malt, torrefied malt and ustulate malt are the three kinds of malt products available in Chinese crude drug market. In this paper, we studied the chemical constituents of malt and the best processing methods for torrefied malt and ustulate malt. At the same time, a method for the quantitative analysis of tricin in raw malt and processed malts by HPLC was established.14 Compounds were isolated from the 95% and 70% ethanol extracts of raw malt by repeated c.c. on silica gel and recrystallization. On the basis of spectral data analysis and physicochemical evidence, 12 of them were identified as N-benzoyl-phenylalanine -2-benzoylamino-3-phenyl propyl ester (1), tricin (2), α-glyceryl monopalmitate (3), tianshic acid (4), (E, E)-9-oxooctadeca-10,12-dienoic acid (5), azelaic acid (6), adenosine (7) , 5-hydroxylmethyl furfural (8), nicotinic acid (9), 7-oxositosterol (10), β-sitosterol (11) and daucosterol (12). All the compounds were newly isolated from malt and, compound 1 and 4 were obtained from the genus Hordeum for the first time.The content of total flavonoids in malt was determined by spectrophotometric method. And the best processing methods for torrefied malt and ustulate malt were achieved as well, which should be meaningful to the quality control of TCM malt.The contents of tricin in barley, raw malt, torrefied malt and ustulate malt were determined by HPLC. Results showed that the content of tricin in barley increased 1.8 folds after sprouting. And the content of tricin in processed malt products increased significantly. Compared with raw malt, the contents of tricin in torrefied malt and ustulate malt increased 0.2 and 0.6 times respectively. These research results showed that the changes of chemical constituents of malt caused by different processed procedures might lead to the changes of its bioactivity.