Fungal Contaminants in Some Deteriorated Food items of Bihar, India: A Survey.

Gazala Tabassum, Chandan Kumar, Choudhary Sharfuddin, Reena Mohanka and Rashmi Komal. Plant Pathology and Microbiology Laboratory, Depertment of Botany.

Patna University. Patna. India.

Email: gazalaarshad@gmail.com

ABSTRACT—A study of fungal diversity on the cooked food viz; boiled rice, chapati, dal, chicken and mixed vegetables were done during July 2007 to February 2008. The samples were collected in sterile polythene bags and brought to the laboratory for further investigation.The pure culture of isolated fungi were developed on Potato Dextrose Agar, Czapek and Richard medium having 6.5 pH level. A diverse array of fungal colony were observed on the food surface. The pure cultures of isolated fungi were incubated on different media for 5 to 7 days at a temperature ranging 27+20C. The isolated mycoflora were identified by comparing microphotographs with authentic manuals of fungi. However, many fungi were observed during the variable climatic condition in course of investigation, but the most prominent were the members of class Ascomycetes and a few from class Phycomycetes and class Deuteromycetes. The deterioration of the food quality was expected, due to the saprophytic nature of mycoflora.

I.

Food provides us a source of energy needed for work and for various chemical reactions i.e., growth processes for repair of injured or worn-out cells, and for reproduction. Food spoilage leads to heavy economic loss in the production phase or in the consumption phase. Factors regulating the microbial growth are pH, moisture content, oxidation- reduction potential, nutrient content, antimicrobial constituents, biological structures as well as the extrinsic parameters.These are storage environment properties affecting the foods and microbes viz; temperature of storage, relative humidity of environment and presence and

concentration of gases in the environment (1,2,3). Spoilage caused by microbes is very sudden, reflecting the exponential nature of growth as is its metabolism. In the present investigation, during July 2007 to February 2008 fungal diversity was estimated on some common food consumed in Bihar, India. For that, five food samples were considered viz; chapati, dal, boiled rice, chicken, and mixed vegetables. In India, especially in Bihar and other developing states lots of people die or become ill due to food quality deterioration. There is lack of proper food storage systems, due to properly refrigeration, improper cooking, polluted water, use of dirty utensils, hot climate, which mean presence of factors that are suitable for fungal growth in food, results in food spoilage. Mycological analysis of food products yields many diverse types of fungi. The extent of contamination is influenced by the prevalence in the environment.

II. MATERIALS AND

The infected home made food samples were collected in sterilized polyethene bags during July 2007 to February 2008 and brought to the laboratory for isolation, identification and characterization. Three different culture medium were prepared viz; Potato-Dextrose-Agar medium, Czapek medium, Richard medium having pH 6.5 and was found suitable for growth and sporulation of many fungi. The isolation of mycoflora and its pure culture were performed in antiseptic condition. Three replica of each petri plates of pure culture were incubated at 27+20C for a period of 5 to 7 days. The slides were prepared with the help of cotton blue, lactophenol. The prepared slides were observed under the high magnification of microscope and were identified by comparing, with the help of authentic manuals of fungi.

168

INTRODUCTION

METHODSKeywords Mycoflora; Media; Saprophytic and, Pure culture. -

2011 2nd International Conference on Biotechnology and Food Science IPCBEE vol.7 (2011) © (2011) IACSIT Press, Singapore

Pure culture and microscopic photographs of fungi isolated from food.

III. RESULTS AND

The growth of microorganisms were affected by intrinsic parameters which are plant and animal tissues that are inherent part.The moisture content must generally be above 0.7 aw (ratio of the vapour pressure of the products to that of pure water or equilibrium relative humidity as a percentage). Molds can begin growing when moisture exceeds about 12% (4).

The mycofloras which were isolated from different types of foods in different seasons, most of them were found to be saprophytic in nature and belonged to the class ascomycetes. Although some of them belongs to class deuteromycetes and zygomycetes.

It was observed in boiled rice, medium of food contained more complex fats and carbohydrates which is an excellent growth medium that prompted the growth of various diverse types of mycoflora. Among the most abundantly found species the prominent are Aspergillus flavus , Aspergillus niger, Aspergillus fumigatus, Aspergillus clavate, Aspergillus ochraceus (5,6,7).

So far the diversity of mycoflora in Chapati is concerned; undoubtedly it is the member of ascomycotina which contributed the maximum. The result was in consonance with (8,9) where Aspergillus species were of significance presence. Next to Aspergillus was found another member i.e., Penicillium (10). Species of Fusarium was also found (11).

It was observed that Chickens are the most perishable foods, because of its chemical composition. It contains water

75.5%, protein 18.0%, Fat2 %, soluble non- protein substances 3.0%, carbohydrate and inorganic substance as well as traces of glycolytic intermediates, traces metals, vitamins (12). Here, the major fungal contaminants found belonged to ascomycetes which were followed by deuteromycetes (13). Vegetables usually having chemical composition of carbohydrates, proteins, lipids, like fatty acids, fatty acid esters, phospholipids, glycolipids, vitamins, and minerals like Sodium, Potassium, Calcium, Magnesium, Manganese, Iron etc. and water. In the mixed vegetables the members of ascomycetes and deuteromycetes together have been found in abundance which comprised the species Alternaria alternata, Cladosporium herbarum holded a significant position. Similarly the species of Fusarium viz; Fusarium graminearum, Fusarium moniliforme showed a remarkable presence. After the deuteromycetes there were the members of zygomycetes found in which the order mucorales consisting of genera Rhizopus, Mucor. The species Mucor hiemalis and Rhizopus oryzae had been found in different seasons. However Syncephalastrum species being a member of same order were found to be very rare. Another member of zygomycetes was also found. Absidia species also showed their almost negligible presence. In the month of May and June, Aspergillus glaucus, Aspergillus flavus, Aspergillus niger, Aspergillus clavate were observed which was also accompanied by the species of Penicillium. Members of Penicillium generally grew over a wider range of temperatures than those of genus Aspergillus. Whereas Aspergillus flavus is the predominant species found on all

169

DISCUSSION

food commodities (14,15). The expected food spoilage is due to fungal enzymes secreted by bringing about the change in certain food components.

REFERENCES [1] M. O. Moss. The environmental factors controlling mycotoxin

production. In: Mycotoxins and Animal Foods, J. E. Smith and R. S. Henderson (Eds.) CRC Press. Boca Raton, Florida. 1991.

[2] K. H. Ominski., R. R. Marquardt, R. N. Sinha and D. Abramson. Ecological aspects of growth and mycotoxin production by storage fungi. Pp. 287-312. In J. D. Miller and H. L. Trenholms (Eds.). Mycotoxin in Grain: Compounds other than Aflatoxin. Eagon Press, St. Paul. Minnesota. 1994.

[3] D. M. Wilson and D. Abramson. Mycotoxin. Pp. 341-391. In D. B. Sauer (Ed.). Storage of Cereal Grains and Their Products. American Association of Cereal Chemists. Inc., St. Paul, Minnesota. 1992.

[4] L. W. Whitlow and W. M. Hagler, Jr. Mycotoxins in feeds. Feedstuffs 76(38): 66-76. 2004.

[5] Y. Ueno and I. Ueno. Isolation and acute toxicity of citreoviridin, a neurotoxic mycotoxin of Penicillium citreoviride Biourge. Jpn J Exp Med 42: 91-105. 1972.

[6] M. Eskola., P. Parikka., A. Rizzo. Trichothecenes, ochratoxin A and zearalenone contamination and Fusarium infection in Finnish cereal samples in 1998. Food Addit. Contam. 18, 707-718. 2001.

[7] Mikio Yamazaki, Yukio Maebayashi and Komei Miyaki. Production of Ochratoxin A by Aspergillus ochraceus Isolated in Japan from Moldy Rice. Applied Microbiology., Vol. 20, No. 3: 452-454. 1970.

[8] P. M. Scott. Aflatoxins. Pp. 22-24. In P. M. Scott, H. L. Trenholm and M. D. Sutton (Eds.). Mycotoxins: A Canadian Perspective. NRCC Publication No. 22848. National Research Council of Canada, Ottawa. 1985.

[9] R. F. Vesonder and B. W. Horn. Sterigmatocystin in dairy cattle feed contamination with Asp. v. Appl. Environ Microbiol 49: 234-235. 1985.

[10] John L. Richard, Glenn A. Bennett, P. F. Ross, P. E. Nelson. Analysis of Naturally occurring Mycotoxins in Feedstuffs and Food. J Anim Sci. 71: 2563-2574. 1993.

[11] Mc Mullen, M., R. Jones, and D. Gallenberg. Scab of wheat and barley: A re-emerging disease of devastating impact. Plant Dis 81: 1340-1348. 1997.

[12] R. A. Lawrie. Meat Science (1st. Ed.). Pergamon Press, New York. 1966.

[13] Federico Laich, Francisco Fierro and Juan F. Martin. Isolation of Penicillium nalgiovense strains impaired in penicillin production by disruption of the pcbAB gene and application starters on cured meat products. Mycological Research. 107. 6: 717-726. 2002.

[14] G. A. Payne., W. M. Hagler, Jr, and C. R. Adkins. Aflatoxin accumulation in inoculated ears of field-grown maize. Plant Dis 72: 422-424. 1988.

[15] G. A. Payne, and M. P. Brown. Genetics and physiology of aflatoxin biosynthesis. Ann Rev Phytopathol 36: 329-362. 1999.

170