BIOAVAILABILITY OF PHYTOCHEMICALS FROM NATURAL PRODUCTS, FOOD AND FOOD SUPPLEMENTS: IMPROVEMENT OF THE PHARMACOKINETICS BY DRUG DELIVERY SYSTEMS

Tembe Estella Fokunang, Mbong Annih Grace, Manju Evelyn Bih, Lem Edith, Dobgima John Fonmboh, Ngo Valery Ngo6, Ngum Samuel, Ben Enoluomen Ehigiator, Lovet Benyella Fokunang, Zelinjo N. Igweze, Tih Pius Muffih and Charles Ntungwen Fokunang*

ABSTRACT

The there is a global strong interest to improve the therapeutic value of drugs through the improvement of bioavailability of many active compounds. The co-administration of active pharmaceutical agents from natural products with improved absorption activities has gained great interest in oral drug delivery. Many phytochemicals from medicinal plants have shown their capacity to improve the bioavailability of co-administered drugs by inhibiting efflux pumps or oxidative metabolism, and influencing the intestinal brush border membrane. Some of these known natural bioactive compounds include quercitine, genistein, glycyrrhizin, nitrile glycosides, sinomenine, piperine, naringin, and many others under study. The status of human nutrition also constitutes an important determinant of the quality of life, morbidity, and mortality. With an increase in nutraceutical potential of foods and food supplement, supported by the claims of health benefits, researchers have strong advocacy awareness and accountability for regulatory compliance of the therapeutic and toxicologic effect of phytochemicals, nutritional supplements and foods. To address the challenges of safety and quality of phytochemicals, an understanding of bioavailability of these products becomes evident. For a better increasing understanding of nutraceuticals, it is important to have an increased understanding of nutrition and therefore physicians, allied health practitioners, patients, and public health policy makers have more sensitization to better understand the basis for efficacy and safety of nutritional supplements and foods. Novel delivery systems that modulate the pharmacokinetics of existing drugs, such as nanoparticles, cyclodextrins, niosomes, liposomes, could be exploited to enhance the delivery of bioactive compounds and enhanced bioavailability at target sites. This review gives an insight into bioavailability in natural products phytochemicals as one of the factors that can enhance significantly the pharmacokinetic profile of a drug. This paper discusses the improvement of drug bioavailability exhibited by natural compounds from plants, some of the delivery approaches that have already made an impact by either delivering a drug to target tissue or increasing its bioavailability by many fold changes.

Keywords: Bioavailability, phytochemicals, pharmacokinetics, natural products, food, toxicology, microbiome, dietary intake, metabolism.