Antimicrobial Analysis And Phytochemical Of Mangifera Indica And Carica Papaya Leaves

1.0 Introduction

1.1 Background To The Study

It is a known fact that in order for a plant to protect itself, it produces some chemicals which can also protect humans against diseases. As many as over 4000 different phytochemicals having potential to affect diseases such as cancer, stroke or metabolic system are in existence today (Arts and Hollman, 2005). Phytochemicals are chemical compounds that naturally occur in plants which are responsible for many attributes of the plants such as smell, taste, colour and other organoleptic properties of the plant. They are classified into curative (or nutritive) such as alkaloid, saponnins, tannins, flavonoids, phenols, glycosides, isoflavones, cartenoids, sulfides, and non-curative (or non- nutritive) such as cyanide, oxalates, terpenes, terpenoids. Though some phytochemicals may have their biological significance because of their established essential nutritional values, however many have been considered as potential drugs because of their therapeutic potentials (Levin et al., 1979). Plants with such phytochemicals are regarded as medicinal plant because they have similar properties as conventional pharmaceutical drugs. The local use of natural plants as primary health remedies, due to their pharmacological properties is quite common. In many part of the world especially in West Africa plant extracts are still widely used in the treatment of malaria and other ailments (World Health Organization, 2002). As a matter of fact, every plant is medicinal on the basis of the contents of their phytochemicals, hence pharmaceutical industries rely heavily on their therapeutic purpose so as to be used as precursors for drug synthesis (Bouayed et al., 2007).

This is because every plant has medicinal value based on the active compounds that can be extracted from its part such as leaves, stems, barks, roots, bulks, rhizomes, woods, flowers, fruits or the seeds for therapeutic purposes. Most phytochemicals such as sulfides (in onions, leeks, and garlic), carotenoid (in carrots), flavonoids (in fruits, vegetables), polyphenols (in tea, grapes) have antioxidant activity and protect our cells oxidative damage and reduce the risk of developing certain types of cancer. Some exhibit hormonal actions such as isoflavones (in soy) which imitate human estrogen and help to reduce menopausal symptoms. Some also stimulate enzyme such as indoles (in cabbages) which makes the estrogen less effective and reduces the risk of breast cancer. Caspacin (in hot pepper) protects DNA from carcinogens while allicin (in garlic) has anti bacteria properties (Manach, 2004).

Alkaloids are naturally occurring organic bases which contain a pyridine ring, invoke a bitter taste and are used in making anti- malaria, hypertension and anti-cancer drugs (Manske, 2009; Kittakoop et al., 2014).Flavonoids have 15-carbon skeleton which consists of two phenyl ring and heterocyclic ring and are known for their anti- inflammatory and anti-allergic effects (Yamamoto and Gaynor, 2001). Glycosides are molecules in which sugars are bound to another functional group via a glycosidic bond (either O- or S-). Digitalis glycosides have served as cardiac drugs in case of heart failure (Brito-Arias and Marco, 2007). Phenols are a class of aromatic organic compound which possess antiseptic properties and may be used as disinfectant (Amorati and Valgimidi, (2012). Saponnin are plant glycosides which serve as anti-feedant and protects plants against microbes and fungi. Some plant saponin aids in nutrient absorption and digestion (Francis, et al., 2002). Steroids are polycyclic compounds which have alkanol functional group and they include cholesterol, the sex hormones (Desmond and Gribaldo, 2009).Tannin refers are phenolic compounds characterized by their ability to precipitate proteins, amino acids and alkaloids. They protect the plant from predation perhaps as pesticides and regulate its growth and helps in the ripening of fruits (Drabble and Nierenstein, 2001).

An antimicrobial is an agent either kills microorganisms or inhibits their growth but causes little or no damage to the host. Antimicrobial therapy refers to the use of antimicrobial medicines to treat infection while antimicrobial prophylaxis refers to the use of antimicrobial medicines to prevent infection (Amyes 1996).

In formulation of animal feed, plant materials are used because they contain phytochemicals which can serve as antibiotic to the animals. Hence there is need to investigate common plants which are easily available, cheap, renewable and nutritive source of material as feed supplements. Mangiferaindica and Carica papaya being edible they have been reported along with the roots and leaves to be of medicinal value (Fowomola, 2010). Mangifera indica also known as mango whose chemical constituent include pharmacologically active hydroxyl- atedxanthone C-glycoside which is extracted from the leaves and bark (Jonathan, 1993) and allergenic urushiols which is extracted from the fruit peel (Cuadra, Pablo, 2007). These phytochemicals are useful as anti-diuretic, anti-diarrheal, anti-emetic and cardiac herb (Gordon, 2012). On the other hand, Carica papaya and is one of species in the genus Carica of the plant family Caricaceae. Papaya leaves are made into tea Fowomola, as a treatment for malaria (Titanji, et al., 2008).

1.2 Statement Of Problem

Continuous spread of infectious diseases is a major apprehension for health institutions, pharmaceutical companies and government thinktanks all over the world. Failure of treatment, particularly with the current escalating trends of multi-drug resistance (MDR) to the available modern drugs or antibiotics among emerging and re-emerging bacterial pathogens leads to serious risks [1]. Prior to this century, medical practitioners whether allopath (medical doctors), homeopaths, naturopaths, herbalists or shamans had to know the plants in their areas and how to use them since many of their drugs were derived from plants [2–5]. Around 1900, 80% of the drugs were derived from plants, however, in the decades that followed, the development of synthetic drugs from petroleum products caused a sharp decline in the pre-eminence of drugs from live plant sources [6–8]. However, with the recent trend of high percentage resistance of microorganisms to the present day antibiotics, efforts have been intensified by researchers towards a search for more sources of antimicrobial agents [1,9].

Mangifera indica is commonly called mango (English), manako (Hawai‘i), manggo’am (Fiji), tharyetthi (Myanmar), mangot, mangue or manguier (French), aam, am or amb (Hindi), bobbiemanja, kanjannamanja, magg, manggaboomormanja (Dutch), mamung (Thailand), manga or mango (Spanish), manga (Portuguese), manga, mempelamorampelam (Malaysia), manggaor mempelamn (Indonesia), mangobaum (German), paho (Philippines) and xoài (Vietnam), mongoro (Yoruba, Nigeria), mangolo (Igbo, Nigeria) and mangoro (Hausa, Nigeria). The fruits are eaten and used in the production of juice and wine. Traditionally, the mango plant has medicinal applications.Mango extract has been reported to have anti malaria effect by Tsabang et al [10] and was found to display in vitro activity against Plasmodium falciparum [11].

The leaves of M. indicahave also been reported to possess antibacterial activity [12]. Ojewole [13] reported the anti-inflammatory, analgesic and hypoglycemic effects of M. indica stem-bark aqueous extract. Doughari and Manzara [12] also affirm that both acetone and methanol extracts inhibited the growth of gram positive bacteria, with acetone extract exerting more activities on all the gram positive bacteria with zone of inhibition between 15 – 16 mm, and a gram negative bacterium Salmonella typhi (14 mm) at 250 mg/ml. Stem bark of M. indica showed significant antibacterial and antifungal activities against Streptococcus pneumoniae, Enterobacter aerogenes, Klebsiella pneumoniae and Candida albicans with MIC of 0.08 mg/ml [14]. Mangifera indica contains alkaloids and glycosides which are of great importance pharmacologically. Certain aliphatic constituents such as coumarin, mangiferin, sequiterpinenoids, triterpinoids and phenolics have also been reported from the stem barks of different cultivars of M. indica [15]. It is believed that the presence of these phytochemicals confers on Mangifera indica, its medicinal ability. Studies have shown that aqueous and ethanolic herbal extracts show less toxicity in animal models than NHaxane, acetone, ethanol and other solvents [1]. This study therefore investigated and revalidated the phytochemical and antimicrobial properties of aqueous and ethanolic extracts of Magniferaindica.

1.3 Aim And Objectives

The major aim of this work therefore was to determine the phytochemicals and antimicrobial agents present in Mangifera indica and Carica papaya. The phytochemical analysis are carried out first qualitatively and then quantitativ.