Project Materials

ISOLATION AND IDENTIFICATION OF BACTERIA FROM FOOD VENDORS AND SOME VEGETABLE AVAILABLE (A Case Study Of Ogbete Market Enugu)

ABSTRACT

Food safety is an essential component of food quality. A total of 25 street food samples (jollof rice, egwusi soup, ugu, water leaf, and green) were purchased at random from five different sellers in Enugu’s Ogbete Main Market. The samples were transferred to the lab on ice. The samples were bacteriologically examined using the pour plate technique and subculture. Pour plate procedures were used by serially diluting the sample, then selecting the first and final tubes and pipetting 1ml of each sample into a Nutrient agar plate. The plate was then incubated for 24 hours at 37oC before being checked for growth. Bacterial agar was used for subculture. All of the food samples tested showed bacterial growth ranging from 1.0 X 105 to 3.0 X 106 cfu/ml. Ninety percent of the examined meals had bacterial counts over the permissible limits (104 cfu/ml), whereas 10% had levels below (<104 cfu/ml). Six bacterial species were identified from the foods tested. Staphylococcus aureus, Bacillus cereus, Vibrio, Salmonella, Escherichia coli, and Shigella spp. More than one pathogenic microorganism was isolated from jollof rice and water leaf. The findings demonstrated that street meals have the potential to transmit food-borne illnesses, necessitating the development of realistic methods for street food safety.

Chapter one

Introduction

Bacteria are a type of microbe that lacks a distinct nuclear membrane (making them more primitive than animal and plant cells) and has a cell wall with a specific makeup. Most bacteria are unicellular; their cells might be spherical (coccu), rod-shaped (bacillus), spiral (spirillum), comma-shaped (vibrio), or corkscrew-shaped (spierocheate). They typically range in size from 0.5 to 5 um. Elizabeth and Martin, 2003.

Food is any material that humans or animals consume or drink, or that plants absorb to sustain life and growth. Food is any material taken to provide nutritional support to the body, which is often of plant or animal origin.

(Ezeronye. 2007). Food is composed of chemical substances that heterophilic living things eat in order to carry out metabolic processes.

They are also compounds that, when given into the digestive system in normal circumstances, aid in growth, repair, and energy production. (Ezeronye. 2007). Foods are categorised into six important nutrients: protein, carbohydrates, vitamins and minerals, fats and oils, and water.

PROTEIN is an organic substance composed of carbon, hydrogen, oxygen, and nitrogen (sulphur and phosphorus may also be present). The protein molecule is a complex structure composed of one or more amino acid chains connected together by peptide bonds.

Proteins are essential constituents of the body; they form the structural material of muscles, tissues, organs, and so on, and they are also important as function regulators, such as enzymes and hormones.

Proteins are synthesised in the body from their constituent amino acids, which are obtained through protein digestion in the diet.

CARBOHYDRATE: – One of a vast group of chemicals, including sugar and starch, that include carbon, hydrogen, and oxygen and have the general formula CX (H2O). Y- Carbohydrates are a significant source of energy since they are produced by plants and received by animals through eating, and they are one of the three major components of food.

Carbohydrates are broken down in the body into glucose, which can be used for energy production. Excess carbohydrate that the body does not immediately require is stored in the liver and muscles as glycogen.

Carbohydrates are key structural components in plants (for example, cellulose) as well as storage products (most often starch). Elizabeth and Martin, 2003.

VITAMIN: Any of a set of nutrients necessary in very small amounts for proper growth and development; they cannot be synthesised by the body and hence must be obtained from diet.

Vitamins are classified into two groups based on whether they are soluble in water or fat. Vitamin C belongs to the water-soluble group, while vitamins A, D, E, and K are fat-soluble.

A lack of sufficient amounts of any of the vitamins in the diet causes particular vitamin deficiency disease (Elizabeth and Martin 2003).

FAT:- A substance that comprises one or more fatty acids (in the form of triglycerides) and is the primary form in which the body stores energy (in adipose tissue). It also acts as an insulator beneath the skin (in the subcutaneous tissue) and around specific organs (including the kidney).

Fat is one of the three primary components of food; it is required in the diet to provide an appropriate amount of vital fatty acids and to facilitate the efficient absorption of fat-soluble vitamins from the intestine. Obesity is the result of excessive fat buildup in the body. Elizabeth and Martin, 2003.

A vendor is someone who sells something (en.wikipedia.org/wiki/vendor). According to the World Health Organisation (WHO), food-borne diseases, the majority of which are of microbial origin, are one of the most common problems in the modern world, accounting for roughly one-third of all deaths worldwide.

Infectious conditions with negative consequences can reduce economic productivity. Most local markets have poor sanitary conditions, and the environment is heavily contaminated and filled with spoilage and pathogenic flora, which is most likely the source of contamination of food items sold by these vendors. (Oweghe et al. 2001).

Poor sanitary conditions in a food environment are known to promote the growth of pathogenic organisms (Egeonu, 2002). Bacillus cereus and Staphylococcus aureus have been reported to grow to oxygenic levels in food at 300 degrees Celsius (Egeonu, 2003).

As a result, microbiological analysis of foods and food contact surfaces can provide information on the raw food’s quality as well as the sanitary circumstances under which it is processed (Michael et al; 2004).

Microorganisms exist throughout the kitchen and can readily move around by attaching themselves to humans, food, and equipment.

Bacteria can transfer from equipment to food that has not been thoroughly cleaned and sanitised before being used to create another dish. Examination of ingested food and its wholesomeness.

This implies that food for human consumption should be pure and free of contamination, particularly from pathogenic and rotting microorganisms.

Failure to ensure the safety and wholesomeness of the foods consumed by the public may result in illness. To keep microorganism contamination to a minimal and ensure good product shelf life, raw materials should be monitored and analysed on a regular basis.

Controlling the spread of food-borne pathogens is crucial for food service facilities. Surfaces such as bench tops and tables can harbour bacteria from contact with people, raw foods, dirty equipment, or cartons stored on the floor. If the bench tops are not thoroughly cleaned, any food on them will be contaminated with bacteria (Kamil, 2005).

1.1 AIM

The general goal of this research is to test chosen items offered by vendors in Ogbete’s main market, Enugu, for bacterial contamination.

OBJECTIVES

1. Isolate and identify bacterial species responsible for food contamination.

2. Determine the microbial load of the isolated bacteria.

3. Determine the public health implications of consuming such foods.