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Mycoflora of sun-dried
sweet potato (Ipomoea batatas L.) slices in Benin
City, Nigeria
F.I. Okungbowa* and M.
Osagie
Department
of Botany, University of Benin, P. M. B. 1154, Benin City,
Nigeria.
*Corresponding author. E-mail:
fiokun2002@yahoo.com.
Tel.: 234-8055376204.
Accepted 30
April, 2009 |
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A study was carried out to isolate and quantify the fungi
present in sun-dried sweet potato slices in Benin City,
Nigeria. Potato tubers were peeled, washed, sliced and
sun-dried for 30 days. Oven-dried slices served as control.
Meteorological data were obtained for the period of study.
Fungal colonies on slices were counted with the aid of a
hand lens and the average number of colonies calculated. The
relative density of each fungus was determined by plating on
potato dextrose agar and incubating for 7 days at ±28°C.
Fungi were isolated and identified and colony forming unit (cfu)
determined. Results revealed 12 fungal species, whereas the
control had no fungal growth. Isolated fungi were
Botryodiplodia theobromae, Rhizopus stolonifer, Mucor mucedo,
Aspergillus niger, A. fumigatus, A. flavus and
Penicillium digitatum in May (relative density =
5.5-29.4%). A. ochraceus, Curvularia sp. and
Neurospora sitophila were isolated in June in addition
to the above fungi (relative density = 2.1 - 23.2%). Eight
fungi were isolated in July (relative density = 2.6 -
26.8%). The cfu ranged from 2.8 x 106 - 11.6 x 106
in May, 1.9 x 106 - 9.1 x 106 in June
to 4.1 x 106 - 11.3 x 106 in July.
Other means of drying such as tunnel dryers (operated at 60
- 70°C) and drum-drying are recommended.
Key
words:
Fungi, sun-drying, sweet potato. |
