ANTIMICROBIAL EFFECT OF ETHANOLIC EXTRACT OF PAWPAW LEAVE ON SOME MICROOGANISMS

ANTIMICROBIAL EFFECT OF ETHANOLIC EXTRACT OF PAWPAW LEAVE ON SOME MICROOGANISMS

CHAPTER ONE

1.0     Introduction

The importance of herbs in the management of human ailments cannot be over emphasized. It is clear that the plant kingdom harbours an inexhaustible source of active ingredients invaluable in the management of many intractable diseases. The active components of herbal remedies have the advantage of being combined with other substances that appear to be inactive. However, these complementary components give the plant as a whole a safety and efficiency much superior to that of its isolated and pure active components (Ahmad, 2011).

There is no plant that does not have medicinal value. The active components are normally extracted from all plant structures, but the concentrations of these components vary from structure to structure. However, parts known to contain the highest concentration of the principles are preferred to therapeutic purposes and it can either be the leaves, stems, barks, roots, bulks, corms, rhizomes, woods, flowers, fruits or the seeds (Kafaru, 2014). Some of the active principles singly or in combination inhibit greatly the life processes of microbes, especially the disease causing ones. They do this by binding their protein molecules, acting as chelating agents (selective binding polyvalent metal ions so that the latter loses its biological activities), altering their biochemical systems, preventing utilization of available interests to the microorganisms, other causes inflammation analysis of microbial cells (Garrod et al., 2015).

The bitter taste, pungent and repulsive smell in some plants; have been found to have repressive ability over the metabolic activities of a wide range of microorganisms. Sofowora, (2012) defined medicinal plants as a plant in which one or more of the organs contains substances that can be used for therapeutic purposes or which it precursors for the manufacturing of drugs are useful for disease therapy. The use of medicinal plants predates the introduction of antibiotics and other modern drugs into the African continent. Since medicinal plants do not merely save people from feeling pain but also permit them to emerge unscathed, then they deserve investigation. The active components in these medicinal attribute are expected to be inimical to the growth of at least some microorganisms especially the disease causing ones e.g. Escherichia coli, Staphylococcus aureus, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa etc. therefore, many studies and researches had been done on the antimicrobial properties of many plants but for this study, the leaf of Carica papaya will be discussed.

The papaya, CaricapapayaLinn, is a member of the family Caricaceae joined with the Passifloraceae and it is a distinctive source of possibly useful compounds with diverse constitutions and properties (Krishna et al., 2008). Papaya exists in three sexual forms: male, female and hermaphrodite. Papaya flowers are born on inflorescences which emerge in the axils of the leaves. Female flowers are held close against the stem as single flowers or in the group of 2 to 3 (Chay-Prove et al., 2020).

Each part of papaya tree has its own economic worth when grown on a business scale (Krishna et al., 2008). The plant parts are found to have some properties like analgesic, amebicide, antibacterial, cardiotonic, cholagogue, digestive, emenagogue, febrifuge, hypotensive, laxative, pectoral, stomachic, and vermifuge properties (Afolayan, 2013). Even though the active components are usually obtained from all parts of the plant, the concentration of these components vary from structure to structure. However, parts known to have the highest concentration are ideal for therapeutic purposes and it can either be the leaves, stem, barks, roots, bulks, corms, rhizomes, woods, flowers, fruits, and the seeds (Kafaru, 2014).

Aim of the study

The aim of this study is to determine the antimicrobial effect of ethanolic extract of pawpaw leave on some microorganism.

1. Objectives of the study
2. To determine the minimum inhibitory concentration of some selected microorganism
3. To determine minimum bactericidal concentration of the extract.