Tyrosinase Inhibitor Fatty Ester and a Quinoline Alkaloid from Skimmia laureola

2005 ◽  
Vol 60 (11) ◽  
pp. 1186-1191 ◽  
Author(s):  
Nighat Sultana ◽  
Tariq H. Khan ◽  

Aerial parts of Skimmia laureola yielded a new tyrosinase inhibitor fatty ester, (+)-skimmidiol (1), and a new alkaloid ribaliprenylene (2). The configuration at C-3’ in 1 was established by Horeau’s procedure. Compound 1 was screened for its enzyme inhibitory activity against tyrosinase (E.C.1.14.18.1), exhibiting activity with IC50 51.25±1.10165 μM.

2016 ◽  
Vol 11 (5) ◽  
pp. 1934578X1601100 ◽  
Author(s):  
Tran Minh Hoi ◽  
Tran Van Thai ◽  
Chu Thi Thu Ha ◽  
Ha Thi Van Anh ◽  
Phan Xuan Binh Minh ◽  
...  

One new flavonol diglycoside, 4′,5-dihydroxy-3,3′,7-trimethoxyflavone 4′- O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside (1), and two known compounds (2–3) were isolated from the methanol extract of Anoectochilus annamensis Aver. aerial parts. The effects were evaluated of all isolated compounds (1–3) on LPS-induced production of the inflammatory mediator nitric oxide (NO) by RAW264.7 cells. 4′,5-Dihydroxy-3,3′,7-trimethoxyflavone (2) was the most active while the addition of a rutinoside at C-4′ (compound 1) decreased the inhibitory activity. This is the first report on the chemical composition and biological activity of A annamensis.


2013 ◽  
Vol 8 (3) ◽  
pp. 1934578X1300800
Author(s):  
Buket Bozkurt Sarikaya ◽  
Strahil Berkov ◽  
Jaume Bastida ◽  
Gulen Irem Kaya ◽  
Mustafa Ali Onur ◽  
...  

A GC-MS analysis of alkaloids in the aerial parts and bulbs of Galanthus x valentinei nothosubsp. subplicatus was performed for the first time. Totally, twenty-six alkaloids were identified, of which tazettine and galanthindole were the major ones. Acetylcholinesterase inhibitory activity of the alkaloidal extracts was determined using modified in vitro Ellman's method. Significant anticholinesterase activity was observed in the tested samples (bulbs: IC50 = 21.3 μg/mL, aerial parts: IC50 = 16.3 μg/mL).


2010 ◽  
Vol 5 (11) ◽  
pp. 1934578X1000501 ◽  
Author(s):  
Lucie Cahlíková ◽  
Lubomír Opletal ◽  
Milan Kurfürst ◽  
Kateřina Macáková ◽  
Andrea Kulhánková ◽  
...  

The roots and aerial parts of Chelidonium majus L. were extracted with EtOH and fractionated using CHCl3 and EtOH. Repeated column chromatography, preparative TLC and crystallization led to the isolation of five isoquinoline alkaloids, stylopine (3), chelidonine (4), homochelidonine (5), protopine (6), and allocryptopine (7), along with two isolation artifacts 6-ethoxydihydrosanguinarine (1) and 6-ethoxydihydrochelerythrine (2). All isolated compounds were tested for human blood acetylcholinesterase (HuAChE) and human plasma butyrylcholinesterase (HuBuChE) inhibitory activity. The isolation artifacts exhibited the highest activity against HuAChE and HuBuChE with IC50 values of 0.83 ± 0.04 μM and 4.20 ± 0.19 μM for 6-ethoxydihydrochelerythrine and 3.25 ± 0.24 μM and 4.51 ± 0.31 μM for 6-ethoxydihydrosanguinarine. The most active of the naturally-occurring alkaloids was chelidonine, which inhibited both HuAChE and HuBuChE in a dose-dependent manner with IC50 values of 26.8 ± 1.2 μM and 31.9 ± 1.4 μM, respectively.


Planta Medica ◽  
2019 ◽  
Vol 85 (11/12) ◽  
pp. 941-946 ◽  
Author(s):  
Ilias Stefanis ◽  
Dimitra Hadjipavlou-Litina ◽  
Anna-Rita Bilia ◽  
Anastasia Karioti

AbstractTargeted isolation based on a combination of NMR and HPLC-PDA-MS of a dichloromethane extract of Thymus vulgaris Varico 3 aerial parts afforded one new p-cymene dimer, 6,3′,4′-trihydroxy-5,5′-diisopropyl-2,2′-dimethylbiphenyl (1), together with two known p-cymene derivatives (2 and 3), as well as five known compounds, namely, thymol (4), oleanolic acid (5), ursolic acid (6), cirsimaritin (7), and xanthomicrol (8). The structural elucidation of all compounds was performed by spectroscopic analyses, including 1D and 2D NMR, and HRESIMS experiments. The biphenyls were assayed for their inhibitory activity on tyrosinase. Compounds 2 and 3 showed negligible activity on tyrosinase, while compound 1 effectively inhibited the enzyme with 35% (± 0.3) inhibitory activity, higher than the inhibition of the reference compound kojic acid (18.6 ± 0.02).


2013 ◽  
Vol 68 (3-4) ◽  
pp. 118-124 ◽  
Author(s):  
Buket Bozkurt Sarikaya ◽  
Nehir Unver Somer ◽  
Gulen Irem Kaya ◽  
Mustafa Ali Onur ◽  
Jaume Bastida ◽  
...  

GC-MS (gas chromatography-mass spectrometry) analyses of alkaloids in the aerial parts and bulbs of Galanthus rizehensis Stern (Amaryllidaceae), collected during two different vegetation periods, was performed. Twenty three alkaloids were identified in four different alkaloid extracts. Acetylcholinesterase (AChE) inhibitory activities of the alkaloid extracts were tested. Both the highest alkaloid diversity and the most potent inhibitory activity (IC50 12.94 μg/ml) were obtained in extracts from the bulbs of G. rizehensis collected during the fruiting period.


2013 ◽  
Vol 8 (12) ◽  
pp. 1934578X1300801
Author(s):  
Mitsuru Satoh ◽  
Yoshio Satoh ◽  
Yasuhiro Anzai ◽  
Daisuke Ajisawa ◽  
Keiichi Matsuzaki ◽  
...  

Two new humulene-type sesquiterpenes, named hyptishumulene I (1) and II (2), have been isolated, together with eight known compounds, a humulene-type sesquiterpene (3), a monoterpene (4) and six abietane-type diterpenoids (5–10) from the aerial parts of Hyptis incana (Labiatae). The cytotoxic activity of the isolated compounds against mouse leukemia cells (L1210) was examined. The abietane-type diterpenoids (5–10) showed rather potent growth inhibitory activity (IC50<15 μM), while the new humulene-type compounds (1 and 2) exhibited moderate activity (IC50>50 μM).


Fitoterapia ◽  
2014 ◽  
Vol 99 ◽  
pp. 1-6 ◽  
Author(s):  
Jian Chen ◽  
Sven Mangelinckx ◽  
Li Ma ◽  
Zhengtao Wang ◽  
Weilin Li ◽  
...  

2013 ◽  
Vol 27 (10) ◽  
pp. 896-899 ◽  
Author(s):  
Parisa Sarkhail ◽  
Pantea Sarkheil ◽  
Farahnaz Khalighi-Sigaroodi ◽  
Abbas Shafiee ◽  
Naser Ostad

ChemInform ◽  
2012 ◽  
Vol 43 (9) ◽  
pp. no-no
Author(s):  
Pham Thanh Ky ◽  
Pham Tuan Anh ◽  
Phan Van Kiem ◽  
Chau Van Minh ◽  
Nguyen Xuan Nhiem ◽  
...  

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Muhammad Gazali

Seaweeds are marine macro algae that can be found attach to the bottom shallow coastal waters with subsrate as attached media. There are three major groups of seaweeds namely brown algae (Phaeophyta), red (Rhodophyta) and green (Chlorophyta). Sargassum sp is one of brown algae which mostly found in the Lhok Bubon Coastal West of Aceh. Recently, exploration of marine macroalgae as bioactive sources was investigated. Seaweed contains bioactive compound which can serve as a defense from ultraviolet radiation that caused hyperpigmentation effect. The aiming of this study is to analyse the tyrosinase inhibitory activity of Sargassum sp extract from Lhok Bubon Coastal Area, West of Aceh. The results shown that the methanol extract of Sargassum sp possess phytochemical properties such as fenol, alkaloid and triterpenoid. Tyrosinase inhibitory activity of Sargassum sp methanol extract  is the best extract which can be inhibit  monophenolase with  IC50 : 1111.49 µg/ml and IC50 = 1582.31 µg/ml in diphenolase pathway with kojic acid as positive control. Moreover, etyl asetate and n-hexane extract have no activity of tyrosinase inhibitor. Therefore, new finding of tyrosinase inhibitor agent from marine macroalgae Sargassum sp give the fruitfull information for cosmeceutical industry.Keywords : Lhok Bubon, Brown Algae, Sargassum sp, Tyrosinase Inhibitor


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