International Journal of Food Science and Nutrition Engineering 2015, 5(1): 53-58
DOI: 10.5923/j.food.20150501.07
Effects of IP6 and Sweet Potato (Ipomoea batatas) Phytate
on Serum, Liver and Faecal Lipids in Rats
Lowell L. Dilworth
1,*
, Felix O. Omoruyi
2
, Helen N. Asemota
3
1
Department of Pathology, The University of the West Indies Mona Campus, Kingston, Jamaica
2
Department of Basic Medical Sciences, The University of the West Indies Mona Campus, Kingston, Jamaica
3
The Biotechnology Centre, The University of the West Indies Mona Campus, Kingston, Jamaica
Abstract Dyslipidemia is associated with coronary heart disease. It is known that phytate supplementation
reduceshepatic triglyceride and cholesterol concentrations in rats. Here, we investigated the effects of sweet potato phytate
extract or IP6 on liver, serum and faecal lipid levels as well as intestinal lipase activity in rats fed zinc deficient of zinc
sufficient diets. There were significant increases in intestinal lipase activity in the test group fed diets supplemented with
sweet potato phytate extract only, compared to other groups. Conversely, faecal triglyceride concentrations were significantly
reduced in this group compared to other test groups. Faecal cholesterol output was significantly increased in rats fed diets
supplemented with phytate extract only compared to other groups. Total serum lipids did not vary among the groups,
however, significantincreases in both serum triglyceride and HDL concentrations were observed in test animals compared to
control groups. Liver phospholipid concentrations were found to be significantly higher in animals that consumed zinc
supplemented diets compared to those on zinc deficient diets. Phytates may induce hypolipidemia by upregulating intestinal
lipase activity resulting in increased faecal cholesterol output and reduced serum lipid levels. Increased serum HDL
concentration in rats fed phytate suggests that this supplement may possess cardioprotective properties.
Keywords Lipids, IP6, Phytic acid, Rats, Sweet potato
1. Introduction
Disruptions in normal metabolic processes oftentimes
result in metabolic consequences in which dyslipidemia
may be a commonly observed event. Dyslipidemia may also
exist on its own as a result of genetic abnormalities
identified and grouped under the Fredrickson’s
classification, or may develop as a complication of an
already existing pathology for example diabetes mellitus.
The recognized association of dyslipidemia with coronary
heart disease has prompted research in the area with much
attention focusing on pathogenesis and treatment. While
statins remain the drugs of choice in some countries, other
research geared towards developing alternative treatment
regimens is ongoing. IP6, sometimes referred to as phytate,
is a naturally occurring compound which has shown
promise in treating dyslipidemia. Research shows that
phytate supplementation reduces hepatic triglyceride and
cholesterol concentrations in rats [1].
Other research shows that phytate supplementation
lowers serum and liver lipid levels but the effects on
triacylglycerol levels were minimal [2]. While phytates are
* Corresponding author:
lowell.dilworth02@uwimona.edu.jm (Lowell L. Dilworth)
Published online at http://journal.sapub.org/food
Copyright © 2015 Scientific & Academic Publishing. All Rights Reserved
predominantly known for their antioxidant, anticancer and
hypoglycemic properties, other studies are needed to
ascertain the mechanisms by which they are able to control
dyslipidemia [3] [4]. Phytates are known chelators of
divalent minerals, but it is theorized that they may also bind
to specific enzymes or enzyme bi-products thereby
affecting the rate of removal of these products from the
gastrointestinal tract. This might be a potential mechanism
by which serum lipids can be modulated by phytates and
this warrantsfurther investigations.
Tuber crops including yams, potato and cassava are
widely consumed throughout the tropics. It is however
thought that sweet potato while highly nutritious, is
underutilized as seen by its reduced consumptioncompared
to other tuber crops. This project therefore sought to
highlight some properties of a bioactive compound found in
sweet potato with a long term view of increasingcultivation
and consumption of the crop. Once accepted into
mainstream, it can serve as a cheap highly nutritious source
of food for millions in the developing world. In addition, it
may also be exploited for health benefits since this crop is a
reservoir for a myriad of bioactive compounds that may
possess beneficial nutraceutical properties. Keeping all this
into consideration, the aim of the present study was to
assess lipid metabolism in rats fed diets containing 5% IP6
or crude sweet potato phytate extract containing 5% phytate
in order to assess the effects of these compounds in the pure