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Australian Journal of Basic and Applied Sciences
Australian Journal of Basic and Applied Sciences
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Abstract: |
Dates palm (Phoenix dactylifera L). always play an important role in the economic,
nutrition and social lives in the Arab countries. Date fruits are one of the most storage products. Fungi
are a source of fruits rot, produce mycotoxins and reduce the economic values of date fruits. Different
fungi, belongs to various fungal species were isolated from the collected date fruit samples at zero
time, one and two months later using dilution plate method on PDA medium at 28± 2 ºC with 12h
light/dark rhythm. The most identified fungi were Aspergillus spp. (A. niger, A. flavus, A. ficuum, A.
japonicus, A. phoenicis, A. terreus and A. caesilleus), Cladosporium sp. (C. cladosporioides),
Penicillium spp. (P. chrysogenum, P. brevi-compactum, P. digitatum, P. duclauxi, P. frequantans, P.
spinulesum, P. purpurogenum, P. uriticae and Penicillium sp.), Fusarium spp. (F. oxysporium and F.
moniliforme), Mucor spp. (M. hiemalis & M. racemosus) and Chalaropsis sp. (C. state). A. niger was
the most detected fungus, while, C. cladosporioides was the lowest detected one. Samples stored at
room temperature contained higher levels of contaminated fungi than those stored under cooling
conditions (1.19 x104 and 0.58 x104 colonies/g dates, respectively). Deglet variety contained higher
load of the isolated fungi and Asabei El-Arose was the lower one (1.07 x104 and 0.67 x104 colonies/g
dates, respectively). Levels of isolated fungi differed among the different regions tested. Hot air and
pasteurization (hot water) treatments of Deglate and Elak varieties reduced the number of contaminated
fungi (1.17, 1.17, 3.00, and 1.17 x104 colonies/g dates, respectively), compared to untreated control
(12.5 and 7.84 x104 colonies/g dates). Washing date fruits with sterile water decreased numbers of
fungal load (6.00 and 2.33 x104 colonies/g dates). Carnation oil was the most effective one on
inhibition growth (18.37 %) of tested fungal followed by ginger oil (57.14%), while olive oil was the
lowest one (74.46%). Penicillium spp. was the most sensitive one (23.37%), followed by C. state
(53.75%), while, A.flavus was the lowest one (65.17%). Carnation oil treatment reduced fungal load
on date whereas the lowest number was detected on both var. tested followed by ginger oil (0.04x104,
and 0.29x104 colonies/g dates respectively), compared to sodium benzwate (0.13x104 colonies/g dates)
water treatment and untreated control (0.34 and 4.67 00x104 colonies/gm dates).
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