title: Pretreatment of garlic powder using sweep frequency ultrasound and single frequency countercurrent ultrasound: optimization and comparison for ACE inhibitory activities.
abstract: The sweep frequency ultrasound (SFU) and single frequency countercurrent ultrasound (SFCU) pretreatments were modeled and compared based on production of angiotensin I-converting enzyme (ACE) inhibitory peptides from garlic hydrolysates. Two mathematical models were developed to show the effect of each variable and their combinatorial interactions on ACE inhibitory activity. The optimum levels of the parameters in SFU were determined using uniform design, which revealed these as follows: total ultrasonic time 1.5 h, on-time of pulse 18 s and off-time of pulse 3 s. Under optimized conditions, the experimental values of SFU and SFCU were 65.88% and 67.78%, which agreed closely with the predicted values of 63.44% and 67.33%. The SFU and SFCU pretreatments both resulted in higher ACE inhibitory activity compared with untreated garlic (p<0.05). However, there were no significant differences in the ACE inhibitory activities and IC₅₀ values obtained from SFCU and SFU pretreatments under optimum conditions (p>0.05).
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, China; Jiangsu Provincial Key Laboratory for Physical Processing of Agricultural Products, Zhenjiang 212013, China. Electronic address: mhl@ujs.edu.cn.
authors.forename: Haile
authors.initials: H
authors.lastname: Ma
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, China; Jiangsu Provincial Key Laboratory for Physical Processing of Agricultural Products, Zhenjiang 212013, China.
authors.forename: Liurong
authors.initials: L
authors.lastname: Huang
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Peng
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, China; Jiangsu Provincial Key Laboratory for Physical Processing of Agricultural Products, Zhenjiang 212013, China.
authors.forename: Zhenbin
authors.initials: Z
authors.lastname: Wang
authors.affiliation: School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Qiaorong
authors.initials: Q
authors.lastname: Yang
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000737:chemistry* / Q000494:pharmacology*; D005737:Garlic / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology*; D011208:Powders; D014465:Ultrasonics / Q000379:methods*
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D010936:Plant Extracts; D011208:Powders
keywords: ACE inhibitory activity; Garlic; Single frequency countercurrent ultrasound; Sweep frequency ultrasound