| Home  | About ScienceAsia  | Publication charge  | Advertise with us  | Subscription for printed version  | Contact us  
Editorial Board
Journal Policy
Instructions for Authors
Online submission
Author Login
Reviewer Login
Volume 40 Number 5
Volume 40 Number 4
Volume 40 Number 3
Volume 40 Number 2
Volume 40 Number 1
Volume 39 Number 6
Earlier issues
Volume 34 Number 3 Volume 34 Number 4 Volume 35 Number 1

previous article next article

Research articles

ScienceAsia 34(2008): 371-376 |doi: 10.2306/scienceasia1513-1874.2008.34.371


Isoflavone content of rodent diets and its estrogenic effect on vaginal cornification in Pueraria mirifica-treated rats


Nontakorn Urasopona,b,c, Yuzuru Hamadad, Kazuo Asaokae, Ubon Poungmalic, Suchinda Malaivijitnondc,*

 
ABSTRACT:     Pueraria mirifica or White Kwao Krua has been extensively studied for its estrogenic effects on reproductive organs and bones using rodents as experimental animals. Commercial rodent diets are usually formulated with soybean products and therefore deliver a high dose of isoflavone phytoestrogens. Using high performance liquid chromatography, we determined the quantities of five major isoflavones (puerarin, daidzin, genistin, daidzein, and genistein) in five lots of standard rodent diets, a soybean-free diet, and two lots of P. mirifica `Wichai-III'. The concentrations of total isoflavones were 38.6–72.4 mg/100 g in the standard rodent diets, 6.1 mg/100 g in the soybean-free diet, and 123.2–157.3 mg/100 g in the P. mirifica. While absent in the rodent diets, puerarin accounted for about half of the isoflavone content in P. mirifica. The levels of genistein and genistin in P. mirifica were very low compared to the level found in the standard rodent diets. Given the same dose of 50 mg/kg BW/day of P. mirifica for 14 days, rats fed with standard rodent diet showed a significantly higher percentage of cornified cells than those fed with soybean-free diet. These findings suggest the potential presence of phytoestrogens in standard rodent diets and its liability to be a confounding factor in estrogenic or phytoestrogenic research.

Download PDF


a Biological Science Ph.D. Program, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
b Department of Animal Science, Faculty of Agriculture, Ubon Rajathanee University, Ubon Ratchathani 34190, Thailand
c Primate Research Unit, Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
d Section of Morphology, Primate Research Institute, Kyoto University, Inuyama, Aichi, 484-8506, Japan
e Department of Cellular and Molecular Biology, Primate Research Institute, Kyoto University, Inuyama, Aichi, 484-8506, Japan

* Corresponding author, E-mail: suchinda.m@chula.ac.th

Received 24 May 2008, Accepted 9 Oct 2008