Pharmacognosy Magazine

ORIGINAL ARTICLE
Year
: 2017  |  Volume : 13  |  Issue : 49  |  Page : 102--114

The inhibition of hepatic and renal glucuronidation of p-Nitrophenol and 4-Methylumbelliferone by oil palm empty fruit bunch lignin and its main oxidation compounds


Norliyana Mohamad Salleh1, Sabariah Ismail1, Mohamad Nasir Mohamad Ibrahim2 
1 Centre for Drug Research, Universiti Sains Malaysia, Penang; Centre for Herbal Standardization, Sains@USM, Bayan Lepas, Penang, Malaysia
2 School of Chemical Sciences, Universiti Sains Malaysia, Penang, Malaysia

Correspondence Address:
Dr. Sabariah Ismail
Centre for Drug Research, Universiti Sains Malaysia, Penang
Malaysia

Background: In order to develop oil palm empty fruit bunch (EFB) lignin as a nutraceutical and health supplement, the investigation of its potential in interacting with other drugs via inhibition of drug-metabolizing enzymes (DMEs) would ensure product safety. Objective: The study was aimed to investigate the in vitro effect of oil palm EFB lignin and its main oxidation compounds on phase II DME UDP-glucuronosyltransferases (UGTs) in rat liver and kidney microsomes. Materials and Methods: The p-nitrophenol (p-NP) and 4-methylumbelliferone (4-MU) were employed as probe substrates in glucuronidation assays. The effect of soda oil palm EFB lignin on Vmax, Km, CLint, Ki, and mode of inhibition of 4-MU glucuronidation in RLM was also determined. Results: The inhibitory potency of oil palm EFB lignin for both p-NP and 4-MU glucuronidation in rat liver microsome (RLM) and rat kidneys microsomes (RKM) was found to be in the rank order of soda > kraft > organosolv. However, the inhibitory potency of its main oxidation compounds were in the rank order of vanillin > syringaldehyde > p-hydroxybenzaldehyde. Soda oil palm EFB lignin exhibited mixed-type inhibition against 4-MU glucuronidation in RLM, showing the change in apparent Vmax and with only a minor effect on Km compared with control. Conclusions: The findings showed that effect of oil palm EFB lignin on both p-NP and 4-MU glucuronidation in RLM and RKM was enhanced by the presence of vanillin as well as flavonoids. Kinetic study showed that soda oil palm EFB lignin exhibited strong inhibition on UGT activity in RLM with mixed-type inhibition mode. Abbreviations used: p-NP: p-Nitrophenol, 4-MU: 4-Methylumbelliferone, EFB: Empty fruit bunch, DME: Drug-metabolizing enzymes, UGT: UDP-glucuronosyltransferase, Vmax: Maximal reaction velocity, Km: Michaelis-Menten constant, CLint: Intrinsic clearance, Ki: Dissociation constant of an inhibitor enzyme complex, 4-MUG: 4-Methylumbelliferone glucuronide, DMSO: Dimethyl sulfoxide, IC50: Half maximal inhibitory concentration, p-NPG: p-Nitrophenol glucuronide, RKM: Rat kidneys microsomes, RLM: Rat liver microsome, UDPGA: UDP-glucuronic acid, TCA: trichloroacetic acid, MPA: mycophenolic acid


How to cite this article:
Salleh NM, Ismail S, Ibrahim MN. The inhibition of hepatic and renal glucuronidation of p-Nitrophenol and 4-Methylumbelliferone by oil palm empty fruit bunch lignin and its main oxidation compounds.Phcog Mag 2017;13:102-114


How to cite this URL:
Salleh NM, Ismail S, Ibrahim MN. The inhibition of hepatic and renal glucuronidation of p-Nitrophenol and 4-Methylumbelliferone by oil palm empty fruit bunch lignin and its main oxidation compounds. Phcog Mag [serial online] 2017 [cited 2019 Jul 15 ];13:102-114
Available from: http://www.phcog.com/article.asp?issn=0973-1296;year=2017;volume=13;issue=49;spage=102;epage=114;aulast=Salleh;type=0