ISOLATION AND IDENTIFICATION OF RHIZOPUS FROM DECAYING BREAD

ABSTRACT

The Isolation and Identification of Rhizopus       from a Decaying Bread were conducted.  The black mould used in the practical was collected from bread.  It is allowed to stay in moist environment or at room temperature for 2 to 3 days.  The mould is then inoculated in the nutrient egar (N.A.) incubated and was isolated and view under the microscope for cultural characteristics.

In the experiment a mass of soft, closely woven white, silky threads was observed.  In the microscope examination, non-deptate masses of round black spores, rhizoid.  This characterized by Rhizopus SP.

In conclusion, since foodstuff from which the mould is isolated is bread, Rhizopus SP which is more prominent in bread than in any other foodstuff.

TABLE OF CONTENTS

Title page

Certification

Dedication

Acknowledgement

Abstract

Table of contents

CHAPTER   ONE

INTRODUCTION

1.1     Aim and Objectives

1.2     Hypothesis

1.3     Statement of Problem

1.4     Significance of Study

1.5     Limitation of the Study

CHAPTER   TWO

2.1     Composition of Bread and It’s Requirement

2.2     Source of Contamination

2.3     Rhizopus as a spoilage Organism

2.4     Physiological Characteristic of Rhizopus

2.5     Myeotoxins

2.6     Preservative

CHAPTER   THREE

METHODOLOGY

3.1     Sample Collection

3.2     Direction for Method of preparation of the Medium

3.3     Isolation Method

3.4     Method of Identification

CHAPTER   FOUR

GENERAL MORPHOLOGY

4.1     general Morphology of Rhizopus

4.2     Mode of Life

4.3     Reproduction of Rhizopus

CHPATER   FIVE

RESULT

5.1     Table I

5.2            Table II

CHAPTER   SIX

CONCLUSION AND RECOMMENDATION

6.1     Conclusion

6.2     Recommendation

          REFERENCES

CHAPTER   ONE

INTRODUCTION

Rhizopus nigricans belongs to a group of fungi known as the “black moulds”.  It is also known commonly as the “read mould” because if grows freely on moist, state bread.  It appears as a delicate black mass.  It is a common mould, which is widespread in occurrence.  Rhizopus forms a mass of soft, closely woven white silky threads.  This mass, which is known as a mycelium is the vegetative part of the Fungs.  Each silky thread like structure is a hypha.  The ‘mycelium grows not only on the surface of the bread but into it as well.   The bread is known as the substrate. 

The mycelium consists of three sorts of hyphae.  These three sorts of hyphae as stolons which grow horizontally on the substrate (bread), rhizoid or root like hyphae which arise at points where the stolons come into contact with the substrate and sport-angiophores.  The rhizoids are much branched hyphae which penetrate into the substrate.  They are able to digest and absorb organic food.  The sporangiophores are erect unbranched hyphae arising from the stolons at the same points where rhizoids are formal. 

They grow vertically upwards and give rise to the reproductive structures called sporangia.  (Sargini et al, 1979).

The common bread mould (Rhizopus) finds new bakery items by means of air-born spores.  Once the baked good is invaded, it won’t be long before black sporangia full of spores are formed.  Rhizopus stolonifera (black mould) causes the black bread mould that forms cottony masses on the surface of moist