Page 83 - 《食品科学技术学报》2020年第4期

7 8 食品科学技术学报摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 2020 年 7 月

Recombination Expression and Enzymatic Characteristics of

Mono鄄 and Diacylglycerol Lipase PrLip

*
LIU Xiaohui,摇 LAN Dongming,摇 WANG Yonghua
(School of Food Science and Engineering, South China University of Technology,
Guangzhou 510641, China)

Abstract: Mono鄄 and diacylglycerol lipase is broadly applied due to its unique substrate specificity. In
this study, a putative mono鄄 and diacylglycerol lipase gene prlip was identified from the genome of a food
safety strain Penicillium roqueforti. The lipase PrLip was obtained by artificial synthesis strategy and
constitutively expressed in Pichia pastoris X33. The lipolytic activity in the broth supernatant reached
22郾 26 U/ mL after fermentation for 60 h at 30 益. The lipase PrLip was purified by anion exchange
chromatography with the purity greater than 90% . The optimal reaction temperature and pH of PrLip were
45 益 and 7郾 0, respectively, and its thermostable half鄄life at 40 益 was about 6 h. The lipase PrLip was
characterized as a mono鄄 and diacylglycerol lipase through hydrolysis and esterification. PrLip had a good
tolerance against temperature and resistance to most surfactants, which is promising for potential
application in industrial scale.
Keywords: mono鄄 and diacylglycerol lipase; Penicillium roqueforti; constitutive expression; Pichia
pastoris; enzymatic characteristic; temperature tolerance
(责任编辑:张逸群)
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Effects of Soybean Peptide on Sleep in Drosophila

1
1
1
YI Guofu ,摇 ZHANG Jian ,摇 LI He ,摇 LIU Xinqi 1,* ,摇 YIN Liduan 2
(1. Beijing Engineering and Technology Research Center of Food Additives/ Beijing Advanced
Innovation Center for Food Nutrition and Human Health / School of Food and Health,
Beijing Technology and Business University,Beijing 100048, China;
2. Yantai New Era Health Industry Co Ltd, Yantai 264006, China)

Abstract: To study the effect of soybean peptides (SBP) on sleep in Drosophila, SBP was prepared by
proteolytic separation of soybean. 20 days鄄old male Drosophilas melangogaster were selected and divided
into 4 groups. The basic medium was used as a blank control group, and three experimental groups were
cultured using basic medium containing 2, 4 and 8 mg / mL SBP, respectively. The sleep duration was
detected by the VideoTrack animal behavior analysis system, and the effects of SBP on circadian clock
genes ( per, tim, clk, cyc) of Drosophila brain, sleep related genes of rate鄄limiting enzymes of
neurotransmitter synthetase (gad, tph, gdh, hdc), and serotonin (5鄄HT) were analyzed. The results
showed that SBP had the best effect on prolongation of sleep in a dose dependent manner on the second
day of sleep monitoring. By stripping the head, the circadian clock genes ( per, tim, clk, cyc) and
neurotransmitter synthetase genes ( gad, tph, gdh, hdc) were analyzed. It was found that SBP
administration prolonged the sleep duration of Drosophila melanogaster by up鄄regulating the levels of tim
and tph and increasing the secretion of 5鄄HT in the brain.
Keywords: soybean peptide; Drosophila; circadian clock gene; neurotransmitter synthetase gene;
serotonin
(责任编辑:李摇 宁)