Extraction optimization study of flavonoids from Humulus lupulus / 中国中药杂志

<p><b>OBJECTIVE</b>To optimize extracting parameters of flavonoids from Humulus lupulus.</p><p><b>METHOD</b>Based on the single factors test on ethanol concentration, material and solvent ratio, extracting temperature and extracting time, orthogonal test was performed and the best combination was confirmed.</p><p><b>RESULT</b>With the optimized technology, the maximal extracting amount of flavonoids from H. lupulus was 78 mg x g(-1).</p><p><b>CONCLUSION</b>The optimal techniques obtained are 45% ethanol extracting at 60 degrees C with material and solvent ratio 1:25 for 90 min.</p>

Optimization of angiotensin I-converting enzyme (ACE) inhibition by rice dregs hydrolysates using response surface methodology / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Angiotensin I-converting enzyme (ACE) inhibitory peptides have been shown to have antihypertensive effects and have been utilized for physiologically functional foods and pharmaceuticals. The ACE inhibitory ability of a hydrolysate is determined by its peptide composition. However, the peptide composition of a hydrolysate depends on proteolytic enzyme and the hydrolysis conditions. In this study, the effect of process conditions on the ACE inhibitory activity of rice dregs hydrolyzed with a trypsin was investigated systematically using response surface methodology. It was shown that the ACE inhibitory activity of rice dregs hydrolysates could be controlled by regulation of five process conditions. Hydrolysis conditions for optimal ACE inhibition were defined using the response surface model of fractional factorial design (FFD), steepest ascent design, and central composite design (CCD).