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Current Issue 2019

  • Pages: 237-244 Vol-16 No-4

    SECONDARY METABOLITES IMPORTANCE IN ALTERNARIA ALTERNATA FUNGUS

    Corresponding Author

    Huda W. Hadi

    hudaalhyali85@gmail.com
  • Abstract

    Authors: Huda W. Hadi

    The Alternaria alternata is from high metabolically active fungi, thus its metabolic products are closely associated phytopathogenicity. Consequently, this phytopathogen causes economic losses in crops, vegetables and fruits. The plant diseases are associated with human and animal health because metabolic products are metabolized within the bodies of living organisms. Melanin has a great role in the fungal resistance to various harsh environmental conditions. Starting from these points, the following article tries to shed some light on some details about the biology, pathogenicity, morphological characteristics of this fungus, and important secreted metabolites towards its hosts.

    Keywords: Alternaria alternata; melanin; secondary metabolism; toxins; conidia.

  • Pages: 227-235 Vol-16 No-4

    SENSITIVITY AND SPECIFICITY OF CONVENTIONAL CULTURE, LIGHT MICROSCOPY, SEROLOGICAL AND MOLECULAR METHODS FOR IDENTIFYING Mycobacterium tuberculosis COMPLEX

    Corresponding Author

    Rawia F. Gamal

    atef_sadik@yahoo.com
  • Abstract

    Authors: Rawia F. Gamal , Abdel-Maksoud M., Hanan A. Nourel-Din, Wasfy M.O., El-Morsi A.A. and Sadik A.S.

    In this study, some different tools, i.e., conventional culture, light microscopy, serological and molecular methods were evaluated for their sensitivities to detect the Mycobacterium tuberculosis complex in forty specimens from animal and human sources. To achieve such goal 20 samples from each of raw milk, animal tissues, and human CSF were collected. Enzyme-linked immunosorbent assay (ELISA) was compared to conventional culture, light microscopy for its sensitivity and specificity to detect the presence of TB pathogen in these samples. Results showed that sensitivity and specificity of 10% &100% for IS6110-targed PCR, 30 and 90% for ELISA, 16.25% and 100% for conventional culturing and 17.5% and 87.0% for light microscopy were recorded. In other mean, the IS6110-targed PCR was relatively more useful in TB diagnosis followed by ELISA. Furthermore, the DNA fingerprinting of three standards TB strains using random amplified polymorphic of DNA-PCR (RAPD-PCR) was carried out in the hope of generating some DNA molecular marker for TB identification. RAPD-PCR finding showed some molecular DNA markers that could be very useful in the identification of tuberculosis strains.

    Keywords: M. tuberculosis complex, TB diagnosis, Light microscopy, ELISA, PCR, DNA fingerprinting, RAPD-PCR.

  • Pages: 219-226 Vol-16 No-4

    CHARACTERIZATION OF CARTENOID PIGMENTS FROM Sargassum polycystum AND ITS ASSOCIATED BACTERIA

    Corresponding Author

    Lia Kusmita

    lia_kusmita@yahoo.com
  • Abstract

    Authors: Lia Kusmita, Sri Achadi Nugraheni, Handung Nuryadi

    Several bacteria are capable to produce various carotenoid pigments, and they may become potential bioresources for pigment production. Bacteria produce pigments for various reasons and it plays an important role. They may help to protect their host from high exposure of UV-light. However, the ability of marine bacteria to produce natural pigments has been less studied. In this study, we tried to isolate and characterize marine pigment-producing bacteria of brown seaweed macroalgae, Sargassum polycystum from Teluk Awur, Jepara. Out of seven bacterial isolates, only one bacterium, SJ04, positively contains pigments. Pigments analysis using HPLC method showed that pigment composition was slightly different between host and associated bacterium. Pheophorbide a, Fucoxanthin, and ?-caroten were detected from S. polycystum as host, whereas Pheophorbide a, and Neoxanthin were detected from the associated bacteria (SJ04). For bacterium identification, molecular genetic approach based on 16S rRNA gene sequence showed that strain SJ04 was genetically closely related to Brachybacterium zhongshanense with 97.97% homology. The opportunity to realize a safe and environmentally friendly with low price , as well as opportunities to find new sources of pigments from bacteria.

    Keywords: Carotenoid pigments, Sargassum polycystum, 16S rRNA gene.

  • Pages: 211-218 Vol-16 No-4

    SENSORY EVALUATION, ANTIOXIDANT, ANTIMICROBIAL ACTIVITIES AND COLOUR OF STRAWBERRY NECTAR ENRICHED WITH PRODIGIOSIN PIGMENT PRODUCED FROM SERRATIA MARCESCENS

    Corresponding Author

    Ali S. Salama

  • Abstract

    Authors: Ali S. Salama, Abbas O. Toliba, Behairy A. Akl

    This study was performed to evaluate the impact of natural red pigment (prodigiosin) extracted from local microorganism of Serratia marcescens as a natural colouring, antioxidant and antimicrobial agents in strawberry nectar. The local S. marcescens was identified by morphological, biochemical tests as well as sequencing a fragment of the 16S rDNA gene as new Egyptian strain namely S. marcescens A1A. The antioxidant scavenging of prodigiosin was examined by 2,2-diphenyl-1-picrylhydrazyl (DPPH). The antibacterial activity of prodigiosin was assayed against three bacterial indicators (B. cereus, Staph. aureus and E. coli) by measuring the inhibition zones using discdiffusion assay on Muller Hinton Agar. The results revealed that the free radical scavenging activity was increased in the prepared solutions with increasing the concentration of prodigiosin. The prodigiosin of S. marcescens A1A has prohibited the growth of tested bacteria effectively. On the other hand, the fortification of strawberry nectar with prodigiosin pigment improved the antimicrobial, antioxidant activities, colour, taste, clarity, thickness and overall acceptability of resulted products.

    Keywords: Serratia marcescens; Prodigiosin; Strawberry nectar; Antioxidant; Antibacterial agent.

  • Pages: 205-209 Vol-16 No-4

    PRODUCING OF PROBIOTICS MONTEREY CHEESE AND STUDY ITS CHEMICAL COMPOSITION

    Corresponding Author

    Sarmad Ghazi Al-Shawi

    sarmadghazi@yahoo.com
  • Abstract

    Authors: Sarmad Ghazi Al-Shawi, Haider Ibrahim Ali and Huda Mohammed Abd

    Chemical composition of three manufactured Monterey cheese (Control Monterey cheese (C), therapeutic Monterey cheese with the single probiotic strain (A) and therapeutic Monterey cheese with mixture probiotic strains (B)) by adding probiotics bacteria was studied at 0, 14, 28 and 42 days of ripening period. Moisture content decreased in all manufactured Monterey cheese (C, A and B) during the ripening period, protein and fat content increased after 42 days of ripening period and reached 23.41, 23.78 and 23.63% respectively for protein whilst 31.20, 31.03 and 30.43% for fat. Salt and ash content in manufactured monterey cheese by using a mixture of probiotics strains was higher than both manufactured monterey cheese with single probiotic strain and control product (without probiotics)

    Keywords: Probiotics, Monterey cheese, Chemical composition.

  • Pages: 195-203 Vol-16 No-4

    PHYSICO-CHEMICAL PROPERTIES OF PROPOLIS AND ITS APPLICATION AS A FOOD PRESERVATIVE IN FISH KOFTA

    Corresponding Author

    Abbas O. Toliba

    beso14omar@yahoo.com
  • Abstract

    Authors: Abbas O. Toliba, Ali Osman, Hanan El-Sayed

    In the current study, the local Egyptian and imported propolis were characterized. The effect of addition of local propolis at different levels (0.5, 1.0, and 1.5%) on the fish (Oreochromis niloticus) kofta shelf life and its quality during storage at 42C for twenty days was estimated. The dominant components found in all propolis samples were guaia-1(10)-en-11-ol (Bulnesol) ranging between 7.32 to 19.5%, guaiol 8.67 to 12.7%, pinostrobin chalcone, 6.66 to 12.2%, ?-curcumene 7.31 to 12.0% and ?-curcumene 4.07 to 8.73%. The highest element content was potassium followed by calcium, sodium and barium for local and imported propolis, respectively. The addition of local propolis to fish kofta had no negative effect regarding the sensory properties at the beginning of storage. It was clearly noticed that the addition of propolis to fish kofta decreased the malondialdehyde production, total counts of bacterial development, and increased the DPPH inhibition in the cold stored fish kofta. And also, the lowest color changes were observed in 1.5% sample followed by 1.0%, 0.5% and finally control. It could be noted that the addition of local propolis to fish kofta prolonged its shelf life.

    Keywords: Propolis, Nile tilapia, Kofta, shelf life, sensory properties