Background:The Streptomyces are considered the most important bacterial source for bioactive compounds production including natural antibiotics. Objective: This study focused on analysis of these products to characterize the most active substances which may contain new antibiotics. Materials and methods: Samples with the highest antibacterial activities (21, M5, N- and D-) were chosen from a previous study after secondary screening for the intracellular (biomass) extract which showed more antagonism efficiency than that observed in extracellular crude extract.Gas chromatography – mass spectroscopy (GC-MS) was preformed to detect the structure of the compounds in intracellular crude extracts in these isolates. Results: The GC-MS analysis showed a total of 49 peaks observed in 4 isolates, isolate M5=14 peaks, isolate D=11peaks, isolate N= 20 peaks and isolate 21= 4peaks. Isolate D-, which showed the highest zone of inhibition in secondary screening than that in other isolates, is associated with the most prevalence active compounds like the Decane derivatives, in addition to Triadimenol; Azetidine, 1-(1,1-dimethylethyl)-3-methyl; Hexanoic acid, 2-ethyl-, 2-ethylhexyl ester and 3,3,7,7-Tetramethyl-1,5-diazabicyclo(3.3.0)octane. While isolate 21, has less peaks in comparing with the other samples, with great occurrence in components: 1-Dimethylaminohexane with molecular formula C8H19N and molecular weight 129 and Propamocarb with molecular formula C9H20N2O2 and molecular weight 188, in addition to many volatile organic compounds. The greatest components of isolate M5 were Triadimenol and 3,3,7,7-Tetramethyl-1,5-diazabicyclo(3.3.0)octane, in addition to the presence of Decane derivatives; amine compounds and Vitamin E. Isolate N- showed a great occurrence with components Triadimenol and Azetidine, 1-(1,1-dimethylethyl)-3-methyl-with a molecular formula C8H17N and with a molecular weight 127; also the presence of an important component Hexanoic acid, 2-methyl- with the molecular formula C7H14O2 and with molecular weight 103 which has been considered as an essential component of muramycin antibiotic; compounds which contain  Benzene ring. Conclusion: The most prominent compounds detected in the selected isolates by using GC-MS technique were Decane derivatives and Triadimenol.

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Contribution/Originality: This study contributes to develop the efficient green chemistry methods which have investigated synthesis of metal nanoparticles

This study was aimed to isolate and identify the fungus  Trichophyton  violaceum  from human  skin  specimens  and evaluate the  activity of  antibacterial  and  plant  essential oils. The results showed of direct microscopy by using KOH examination and morphological identification, nine samples from skin were positive in KOH test. Microscopical examination appeared that colonies of T. violaceum were coarse with abundant aerial mycelium on SDA, growth rates 6-8cm/14 days.  The color changes with age from white in the middle to brownish yellow at the edges which was more intense on the reverse side.  Susceptibility test to antibacterial showed that 100% of T.Violaceum T2 isolate was resistant to TE (Tetracycline), AK (Amikacin), CTX (Cefotaxime), CFM (Cefixime), CIP (Ciprofloxacin), ERY (Erythromycin) and STR (Streptomycin). Also results showed that all plant essential oils at different concentrations significantly inhibit growth of T. violaceum T2. However,  the  peppermint  oil,  Myrrh  oil,   Cardamom oil,  Chamomile oil  and  Castor oil  at  highest concentration (25mg / ml) caused highest reduction of mycelia growth (100%) followed by Olive oil (67.3%)  and Clove oil (64%) at the same  concentration,  compared with the control  treatment.  

This study aimed to evaluate efficiency of the bioproduct of the bacterium B. licheniformis to degrade aflatoxin B1 produced by A. flavus. Results showed that 11 isolates belonging to the genus Aspergillus spp. Five isolates diagnosed as A. flavus and 5 isolates as A. niger. Colonies were identified by morphological characteristics, colony characterized of A. flavus were Yellow -Green color on PDA medium. The bacterium B. licheniformis is highly effective in inhibiting the fungus A. flavus p3 in the culture medium. Percentage of inhibition zone reached 85% caused by the fungus A. flavus compared with the control. The medium Aspergillus flavus parasiticus agar (AFPA) was used to test the ability of A. flavus for aflatoxin production. A. flavus varied in producing aflatoxin. Results revealed that the three isolates P2, P3 and P7 are aflatoxin producers, but P6 and P11 can't produce aflatoxin. On the other hand, results showed variation in A. flavus isolates in producing the aflatoxin. The isolate (P3) was more produce able of aflatoxin. Moreover, Results showed aflatoxin B1 after the treatment with the fungus A. flavus, recorded 32µg/kg, compared to treatment with B. licheniformis + A. flavus and the control treatment.