Accelerator-based analytical technique in the study of some anti-diabetic medicinal plants of Nigeria

Abstract

Diabetes mellitus, a clinical syndrome characterized by hyperglycemia due to deficiency of insulin, is a disease involving the endocrine pancreas and causes considerable morbidity and mortality in the world. In Nigeria, many plants, especially those implicated in herbal recipes for the treatment of diabetes, have not been screened for their elemental constituents while information on phytochemistry of some of them is not available. There is therefore the need to document these constituents as some of these plants are becoming increasingly important as herbal drugs or food additives. The accelerator-based technique PIXE, using the 1.8 MeV collimated proton beam from the 2.5 MV AN 2000 Van de Graaff accelerator at INFN, LNL, Legnaro (Padova) Italy, was employed in the determination of the elemental constituents of these anti-diabetic medicinal plants. Leaves of Gardenia ternifolia, Caesalpina pulcherrima, Solemostenon monostachys, whole plant of Momordica charantia and leaf and stem bark of Hunteria umbellata could be taken as vegetables, neutraceuticals, food additives and supplements in the management of diabetes. However, Hexabolus monopetalus root should be used under prescription.

Introduction

One of the most dangerous and life threatening diseases in the world today, involving the pancreas, is Diabetes mellitus [1]. It is a clinical syndrome characterized by high levels of glucose in blood and urine due to absolute or relative insulin insufficiency in the body as well as its resistance, and hence a wasting disease [2]. The intimidating record of its prevalence in the world today and the increase in morbidity and mortality rates calls for an urgent attention from the health professionals, policy makers and executioners in tackling this disease. In 1997/98, the World Health Organization (WHO) estimated that 130 million people around the world have diabetes while 300 millions are expected to be diabetic by the year 2025 [2]. In Nigeria, a country with the largest population in Africa, a national prevalence of 2.2% and a trend of a significant increase in prevalence with age was reported in 1998 [3]. Many plants used in herbal recipes for the treatment of diabetes in Nigeria, have been documented [4] while pharmacological reports on some of them have confirmed this activity [5]. Information on their chemical and elemental constituents is generally lacking [4]. Nevertheless, they are becoming more relevant as herbal drugs owing to the increase in their use as antioxidants, neutraceuticals, food additives and supplements. The elements do not always occur singly in plants but are usually associated with organic molecules. However, whichever way they are taken either as infusion, decoction, powder or food, they must undergo metabolism/catabolism which makes these elements available to human body. Some of these plants, listed in Table 1 and collected in their natural habitats from different locations in Nigeria were investigated for their elemental constituents using particle-induced X-ray emission, PIXE. The information generated will be useful for their safe consumption and as additional data for their monographs in the proposed National Pharmacopoeia.