Thesis Abstract

Abstract
The isolation of micrococcus from fermented ugba was conducted to study the microbial diversity present in this Nigerian indigenous food product. Ugba is a popular fermented oil bean seed snack consumed in Nigeria and other West African countries. Micrococcus species are known to be common inhabitants of fermented foods due to their ability to adapt to the harsh conditions prevalent during fermentation. In this study, samples of ugba were collected from local markets in Nigeria and processed in the laboratory for the isolation of micrococcus species. The samples were serially diluted and plated on nutrient agar plates followed by incubation at optimal conditions for bacterial growth. Colonies with characteristic morphological features of micrococcus, such as circular shape, creamy white color, and convex elevation, were selected for further analysis. Biochemical tests including catalase production, oxidase reaction, and Gram staining were performed to confirm the identity of the isolated colonies as micrococcus species. Molecular techniques such as polymerase chain reaction (PCR) and sequencing of the 16S rRNA gene were employed for accurate identification of the isolated micrococcus strains. The results revealed the presence of diverse micrococcus species in the fermented ugba samples, indicating the rich microbial community associated with this traditional food product. The study contributes to the understanding of the microbial composition of ugba and highlights the potential role of micrococcus species in the fermentation process. Furthermore, the isolated micrococcus strains could be further characterized for their probiotic properties and potential applications in food biotechnology. Overall, this research sheds light on the importance of studying the microbial diversity in traditional fermented foods like ugba and underscores the need for further investigations to explore the functional roles of microorganisms in food fermentation processes.

Thesis Overview

1.0   INTRODUCTION

Ugba also called ukpaka is a popular food delicacy in Nigeria especially among Ibo ethnic group. It is rich in protein and is obtained by a solid state fermentation of the seed of African oil bean tree (Pentaclethra macrophylla Benth). It is essential food item from various traditional ceremonies where it is mixed with slices of boiled stock fish (ugba and okpoloko). The natural fermentation of the seed which at present is still done at the house-hold level, renders the production nutritious, palatable and non-toxic (Enujiugha, 2002).

Its production, like many African fermented foods depends, entirely on mixed fermentation by microorganism from diverse source.

Some of these seeds have been exploited as soup bases such as Gbegiri from Vigna unguicuata (Akanbi, 1992). Others are fermented and used as condiments and seasonings such as okpei from Prosopis africana (Achi, 1992) and ogiri from Ricinus cummunis (Odunka, 1989). Another of such seeds is the African oil bean seed (Pentaclethra macrophylla Benth), a highly nutritious leguminous crop seed abundant in the rain forest areas of west and central Africa.

Pentaclethra macrophylla Benth is a large woody plant abundant in the rain forest areas of west and central Africa. It’s origin in Nigeria is believed to be around 1937 (Ladipo, 1984); where it is found in the South Nigeria, (Mbajunwa et al, 1998).

“Ugba” Pentaclethra macrophylla Benth belongs to the Family Leguminosae and sub-family microsoideae (Keay, 1989 and NFTA, 1995).

Ugba seeds are irregular and oval, they are flat, black and hard pods. It is composed of oil, protein and small amounts of carbohydrate (Obeta, 1982).

Production of Ugba is still on age old traditional family in the rural area. The fermentation depends on random inoculation of boiled slices of the oil bean seed by microorganism within he immediate environment. Earlier report attribute the sources of the micro-organism to the leaves used in packaging, human handling, container and utensils used in processing (Obeta, 1993, Odunfa & Oyeyiola, 1985).

A number of researches have been carried out to know what causes this fermentation, and was attributed to micro-organisms that are probably introduced through the air, water, and banana leaves. Organisms such as Micrococus roseus, Micrococcus luteus, Leuconostoc mesenteroides, Staphylococcus aureus, Staphylococcus epidermidis, Bacillus substilis, Bacillus megaterium and Bacillus circclans, E-Coli

Fermented African oil bean seed (ugba), has a high rate of susceptibility to microbial spoilage and therefore has a very short self life of 1-2 weeks (Enujiugha & Olajundoye, 2001).

Manifestation of food spoilage are many and vary typically resulting in an off smell, colour, taste and texture.

Reports by Mbajunwa (1998) Obeta, (1983) and Nwagu et al. (2010) indicates that micrococcus species do not play an active role during microbial fermentation of Ugba.

However, further work on spoilage association of ugba by Nwagu et al (2010) showed that the population of Micrococcus sp increased with increase in keeping time of ugba. This indicates the ability of micrococcus to thrive in the alkalophilic environment while constituting as a spoilage organism of ugba. This may be attributed to the ability of microorganism to produce amylase, lipase, or protease able to utilize protein, carbohydrate or lipid content of ugba as source of nutrition (Njoku et al., 1990).

Amylases are enzymes that breakdown starch or glycogen. The amylases can be derived from several sources such as plants, animals and microbes. The major advantage of using microorganisms for production of amylase is in economical bulk production capacity and microbes are also easy to manipulate to obtain enzymes of desired characteristics

1.1   Aims and Objectives

This work is aimed at the following;

a.           isolating micrococcus from fermented ugba

b.           producing amylase from the micrococcus from ugba