Studies on the microorganisms associated with spoilt carrots obtained from Ose Market, Onitsha, Nigeria were carried out using standard cultural techniques. Nutrient agar, sabouraud dextrose agar and Eosin methylene blue agar were the growth media for the isolation of the heterotrophic bacteria, fungi and coliforms. The bacteria were identified as Serratia marcescens, Escherichia coli and Corynebacterium bovis while the fungi was identified on the basis of their colonial and microscopic characteristics as Penicillium digitatum, Rhizopus stolonifer, Aspergillus niger and Alternaria alternata. Escherichia coli was predominantly isolated among the bacterial isolates (50%) while Aspergillus niger occurred most frequently than the other fungal species (40%). These organisms may have been introduced to the carrots during growth, harvesting, handling, storage and distribution. The presence of the organisms is a public health risk because of the diseases known to be caused by them. It is therefore imperative that adequate hygienic practices must be put in place during the storage and handling of carrots. Spoilt carrots must also not be consumed as they contain a teaming population of bacteria and fungi, some of which are pathogenic to humans.

Vegetables are considered as leafy out-growth of plants or plant shoots used as food. These include those plants or plant parts used in different ways such as in soup or served integral as part of main meal [1]. They can also be regarded as the edible components of plants, which include leaves, stalks, roots, tubers, bulbs, flowers and seeds [2]. They are important protective foods and are highly beneficial for the maintenance of health and prevention of diseases [2]. They offer the most rapid and lowest cost method of providing adequate supplies of vitamins, minerals, and fibers. These ingredients are essential for proper function of the body [2]. The incidence of microorganisms in vegetables may be expected to reflect the microbiological condition of the raw products at the time of processing [3]. These vegetables are frequently consumed without being exposed to those processes that reliably eliminate pathogens. Many viruses, bacteria and protozoans on vegetables which can cause food poisoning are derived from human faeces [3]. Certain fungi such as Aspergillus, Fusarium and Penicillum are commonly occurring filamentous fungi found in vegetables and their growth may result in production of mycotoxins, which can cause a variety of illnesses in humans, from allergic response to immune suppression and cancer [3].

Carrot (Dacus carota) is a root vegetable which contains the important biological active compound carotenoid [4]. It is one of the major vegetable crops cultivated worldwide and is susceptible to microbial spoilage. The consumption of carrots in Nigeria has increased tremendously in the recent years due to increased awareness of its health importance [2]. Local utilization of carrots is limited to direct unprocessed eating either wholly or as salads. It is estimated that 20% of carrots harvested for human consumption are lost through microbial spoilage, though other factors such as enzymatic spoilage and insect attacks are also implicated.

Deterioration of foods generally is attributed to two main causes which are natural degradation due to activities of enzymes and growth of microorganisms (bacteria, molds and yeasts). These microorganisms can result in useful products through their activities particularly during fermentation of foods such as wine and cheese. The negative effects of these microbial activities result in decay, rotting of food and food poisoning hence the basis of microbial food spoilage occurs when these microorganisms release their own enzymes into the foods and absorb the nutrients thereby changing the physical and chemical states of the foods thus lowering the nutritional value. Bacteria and fungi may also produce waste products which act as poisons or toxins, thus causing the renowned ill-effects (Bakri et al., 2010).

Carrot also has several industrial applications due to the proteolytic enzyme called papain hence their use in the production of chewing gums, tenderizing meat and drug preparation for various digestive ailments and for the treatment of gangrenous wounds as well as in the textile and cosmetics industries (Kochhar, 1986; Villegas, 1997). Biochemically, its leaves and fruits are good sources of several proteins and alkaloids with application to pharmaceutical, food, industries, e.t.c. (El Moussaoui et al., 2001). The seed is used to expel worms and the flower may be taken in an infusion to induce menstruation (Duke, 1984 and Oduola et al., 1986). Increasing interest in medicinal herbs has increased scientific scrutiny of their therapeutic potentials and safety thereby providing physicians with data to help patients make wise decisions about their use (“O”Hara et al., 1998).

The primary agents of microbial spoilage are bacteria and molds [5]. These organisms can be introduced to the crop during growth in the field, during harvesting and post-harvest handling or during storage and distribution [6]. Many of these organisms are pathogenic and have been known to cause diseases in humans and animals; therefore it is imperative that the microorganisms associated with the spoilage of this vegetable in the biological environment characteristic of Nigeria are known. Thus in this work, the microorganisms associated with spoilt carrots obtained from Ose Market Onitsha, Anambra State, Nigeria, were isolated, characterized and identified.

Carrot is a useful plant with nutritional, medicinal and health benefits. In spite of all these benefits, the plant is besieged by lots of pathogens both in the field and post-harvest diseases and these diseases result in yield losses thus making its valuable components unavailable. The carrot farm in Covenant University is particularly useful as a source of raw materials for the production of some patented products. This farm is however, infested with pathogens on fruits, stems, and leaves resulting in huge yield losses making the desired raw materials unavailable.

• To isolate the microorganisms associated with the rot diseases of fruits, stems and leaves of carrot

• To identify and characterize the isolated microorganisms.

• To determine the pathogenicity of the isolated microorganisms for carrot.

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