Phenolic Inhibitors of α-Amylase and Trypsin Enzymes by Extracts From Pears, Lentils, and Cocoa

Inhibition of α-amylase and trypsin by phenolic extracts of various fruit and vegetable foodstuffs (pears [Pyrus communis], lentils [Lens esculenta], and cocoa beans [Theobroma cacao]) was studied. An appropriate methodology for determining the percentage of inhibition of each enzyme was developed. A concomitant study carried out using standard substances (gallic acid, (+)-catechin, tannic acid, and condensed tannins) showed that polymeric phenols were more potent inhibitors than the simple forms, all of them having different behaviors towards the enzymes, depending on their chemical characteristics. The inhibitory potency of the extracts varied according to the phenolic composition of each and was intermediate between that of the simple and that of the more complex phenolic compounds. Inhibition of α-amylase by the phenolic extracts (at equal concentrations) was of the same order of magnitude, even though the phenolic nature and content in the three foodstuffs differed substantially. In contrast, in the case of trypsin, the lentil and cocoa extracts displayed inhibition 10 times greater than that of the pear extract.

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Effects of cocoa clones and fermentation times on physical and chemical characteristics of cocoa beans (Theobroma cacao L.)

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/528/1/012079 ◽

2019 ◽

Vol 528 ◽

pp. 012079

Author(s):

A Assa ◽

Rosniati ◽

M R Yunus

Keyword(s):

Theobroma Cacao ◽

Chemical Characteristics ◽

Cocoa Beans ◽

Physical And Chemical Characteristics ◽

Physical And Chemical ◽

Theobroma Cacao L

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Comparison of the Potency of 8-L-Arginine, 8-D-Arginine and 8-D-Homoarginine Vasopressin Analogs with Substituted Phenylalanine in Position 2

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19941439 ◽

1994 ◽

Vol 59 (6) ◽

pp. 1439-1450 ◽

Cited By ~ 2

Author(s):

Miroslava Žertová ◽

Jiřina Slaninová ◽

Zdenko Procházka

Keyword(s):

Amino Acid ◽

Solid Phase Synthesis ◽

Solid Phase ◽

Basic Amino Acid ◽

The Other ◽

Side Chain ◽

Inhibitory Potency ◽

Phase Synthesis ◽

Other Hand ◽

Order Of Magnitude

An analysis of the uterotonic potencies of all analogs having substituted L- or D-tyrosine or -phenylalanine in position 2 and L-arginine, D-arginine or D-homoarginine in position 8 was made. The series of analogs already published was completed by the solid phase synthesis of ten new analogs having L- or D-Phe, L- or D-Phe(2-Et), L- or D-Phe(2,4,6-triMe) or D-Tyr(Me) in position 2 and either L- or D-arginine in position 8. All newly synthesized analogs were found to be uterotonic inhibitors. Deamination increases both the agonistic and antagonistic potency. In the case of phenylalanine analogs the change of configuration from L to D in position 2 enhances the uterotonic inhibition for more than 1 order of magnitude. The L to D change in position 8 enhances the inhibitory potency negligibly. Prolongation of the side chain of the D-basic amino acid in position 8 seems to decrease slightly the inhibitory potency if there is L-substituted amino acid in position 2. On the other hand there is a tendency to the increase of the inhibitory potency if there is D-substituted amino acid in position 2.

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