Antioxidant Flavonols and Phenolic Compounds from Atraphaxis frutescens and Their Inhibitory Activities against Insect Phenoloxidase and Mushroom Tyrosinase

2016 ◽  
Vol 79 (12) ◽  
pp. 3065-3071 ◽  
Author(s):  
Batsukh Odonbayar ◽  
Toshihiro Murata ◽  
Javzan Batkhuu ◽  
Kosho Yasunaga ◽  
Rina Goto ◽  
...  
Medicines ◽  
2019 ◽  
Vol 6 (4) ◽  
pp. 113 ◽  
Author(s):  
Amina Ibrahim Dirar ◽  
Mikiyo Wada ◽  
Takashi Watanabe ◽  
Hari Prasad Devkota

Background: Blepharis linariifolia Pers. (Family: Acanthaceae) is used in traditional medicines as a general tonic and for the treatment of various health problems in Sudan. The main aim of this study was to isolate and identify the major chemical constituents from the aerial parts of B. linariifolia and evaluate their bioactivities. Methods: The dried aerial parts of the plant were extracted successively with 100% acetone and 50% acetone, and thereafter the combined extract was subjected to repeated column chromatography to isolate the main components. Free radical scavenging activity was evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical method, and in vitro enzyme inhibitory activities against α-glucosidase, pancreatic lipase, and mushroom tyrosinase were evaluated. Results: From the detailed chemical analysis, verbascoside (1), vanillic acid (2), apigenin (3), and 6″-O-p-coumaroylprunin (4), were isolated and their structures were identified on the basis of their nuclear magnetic resonance (NMR) spectral data. Among the isolated compounds, verbascoside (1) showed the most potent free radical scavenging activity (IC50 = 22.03 ± 0.04 μM). Apigenin (3) and 6″-O-p-coumaroylprunin (4) showed promising inhibitory activities against all tested enzymes. Apigenin (3) showed the most potent inhibitory activity against α-glucosidase and tyrosinase (IC50 = 34.73 ± 1.78 μM and 23.14 ± 1.83 μM, respectively), whereas 6″-O-p-coumaroylprunin (4) showed potent inhibition for lipase (IC50 = 2.25 ± 0.17 μM). Conclusions: Four phenolic compounds were isolated and identified from B. linariifolia acetone extract, which are reported for the first time from this plant. All compounds showed good DPPH free radical scavenging activities, with verbascoside (1) being the most potent. Apigenin (3) was the most active as α-glucosidase and mushroom tyrosinase inhibitor, while 6″-O-p-coumaroylprunin (4) showed potent inhibitory activity for pancreatic lipase.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Elisa Di Stefano ◽  
Apollinaire Tsopmo ◽  
Teresa Oliviero ◽  
Vincenzo Fogliano ◽  
Chibuike C. Udenigwe

Abstract Type 2 diabetes mellitus (T2DM) is a leading cause of death globally. T2DM patients experience glucose intolerance, and inhibitors of dipeptidyl peptidase IV (DPP-IV) and α-glucosidase are used as drugs for T2DM management. DPP-IV and α-glucosidase inhibitors are also naturally contained in foods, but their potency can be affected by the food matrix and processing methods. In this study, germination and solid-state fermentation (SSF) were used to alter pulse seed microstructures, to convert compounds into more bioactive forms, and to improve their bioaccessibility. Germination substantially modified the seed microstructure, protein digestibility, contents and profiles of phenolic compounds in all the pulses. It also increased DPP-IV and α-glucosidase inhibitory activities in chickpeas, faba beans and yellow peas. Compared to germination, SSF with Lactobacillus plantarum changed the content and the profile of phenolic compounds mainly in yellow peas and green lentils because of greater disruption of the seed cell wall. In the same pulses, heat treatment and SSF of flour increased DPP-IV and α-glucosidase inhibitory activities. The results of this study suggest that germination and SSF with L. plantarum are effective and simple methods for modulating phenolic and protein profiles of common pulses and improve the action on DPP-IV and α-glucosidase.


2020 ◽  
Vol 35 ◽  
pp. 28-36 ◽  
Author(s):  
Marie Schmitt ◽  
Abdulmagid Alabdul Magid ◽  
Jane Hubert ◽  
Nicolas Etique ◽  
Laurent Duca ◽  
...  

2015 ◽  
Vol 19 ◽  
pp. 174-181 ◽  
Author(s):  
Ping Hu ◽  
Dahong Li ◽  
Kaibo Wang ◽  
Hao Wang ◽  
Zihou Wang ◽  
...  

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Ping Jiang ◽  
Jia Xiong ◽  
Fei Wang ◽  
Mary H. Grace ◽  
Mary Ann Lila ◽  
...  

This study evaluated the inhibitory effects of different extracts and fractions from Eucalyptus. grandis × urophylla bark (EB) against α-glucosidase and α-amylase enzyme activities. The ethyl acetate extract (EB-E) showed the highest activity among others. Seven fractions were derived from EB-E; among them EB-E-7 showed the highest significant inhibition of both enzymes, with IC50 of 1.40±0.18 and 1.72±0.12 μg/mL, respectively. EB-E and its active fraction EB-E-7 showed highest contents of total phenolics: 178.79±4.68 and 920.4±5.46 mg GAEag−1, respectively. HPLC-MS analysis of EB-E-7 revealed the presence of ellagic acid, quercetin-glucuronide, quercetin-3-α-rhamnopyranoside, and ellagic acid rhamnoside as major compounds, together with smaller concentrations of myricetin-rhamnoside, isorhamnetin-hexoside, myricetin-3-α-arabinofuranoside, and isorhamnetin. Therefore, the phenolic compounds from Eucalyptus grandis × E. urograndis bark potently inhibited α-amylase and α-glucosidase activity, having potential in prevention of hyperglycemia.


2017 ◽  
Vol 27 (4) ◽  
pp. 480-487 ◽  
Author(s):  
Prachyaporn Inthongkaew ◽  
Nutputsorn Chatsumpun ◽  
Chonlakan Supasuteekul ◽  
Tharita Kitisripanya ◽  
Waraporn Putalun ◽  
...  

2021 ◽  
Vol 15 (4) ◽  
pp. 254-260
Author(s):  
Penghua Shu ◽  
Yamin Li ◽  
Yuehui Luo ◽  
Shujing Cai ◽  
Yingying Fei ◽  
...  

A phytochemical study on the flowers of Cercis glabra ‘Spring-1’ led to the isolation and identification of twelve compounds, including one new compound named as 1-O-α-l-rhamnosyl-(E)-phytol (1) and eleven known compounds. Their structures were elucidated based on physical data analysis, including HR-ESI-MS, NMR, UV, IR, and acid hydrolysis. All compounds were screened for in vitro antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl method. Compounds 4 and 5 exhibited obvious DPPH radical scavenging activities. All the isolates were tested for their inhibitory effects on mushroom tyrosinase, and compounds 6, 7, 10 and 11 showed moderate tyrosinase inhibitory activities.


Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
F Namjooyan ◽  
H Moosavi ◽  
A Jahangiri ◽  
M Azemi

Antioxidants ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 247 ◽  
Author(s):  
Teerapat Rodboon ◽  
Seiji Okada ◽  
Prasit Suwannalert

The anti-melanogenic bioactivities of phytophenolic compounds have been well recognized. Riceberry rice contains a rich source of phenolic compounds that act as melanin inhibitors through their antioxidant and anti-tyrosinase properties. Germination has been shown to be an effective process to improve targeted phenolic compounds. In this study, germinated riceberry rice extract was tested for antioxidant activity. Total phenolic content was determined while the tyrosinase inhibitory effect was screened by the in vitro mushroom tyrosinase assay. Cytotoxicity of germinated riceberry rice extract was investigated in B16 cells before evaluating its activities on cellular tyrosinase, melanogenesis, melanin excretion, morphological appearance, and cellular oxidants. Germinated riceberry rice extract showed increased potency of antioxidants and was also twice as effective for mushroom tyrosinase inhibition when compared with ungerminated riceberry rice extract. In B16 cells, the extract inhibited cellular tyrosinase, melanogenesis, and cellular oxidants in a dose-dependent manner when compared with untreated cells. Germinated riceberry rice extract also displayed an effect on B16 cells morphology by reducing the number of melanin- containing cells and their dendriticity. Additionally, the germination of riceberry rice dominantly enhanced two phenolic acids, protocatechuic acid and vanillic acid, which have the potential for antioxidant-associated hyperpigmentation control. Thus, the restricted germination of riceberry rice tended to promote protocatechuic acid and vanillic acid, which dominantly displayed antioxidants and tyrosinase-related melanogenic inhibition.


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