Pusat Pengajian Sains Kajihayat - Monograf

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    Heavy Metal Concentrations In Bukit Merah Reservoir And Human Health Risk Due To Fish Consumption
    (2022-06)
    Che Abdullah, Mohd Ilman
    The freshwater ecosystem, such as Bukit Merah Reservoir (BMR), plays an important role ecologically and economically to the local population. The contamination of heavy metals in the surface sediment of BMR may cause adverse effects on the living biota in the reservoir and ultimately affect humans' health. This study's objectives were to evaluate the spatial distribution of heavy metals in the surface sediment of BMR and assess the ecological index assessment. This study also investigated the bioaccumulation of heavy metals in different parts of eight fish species found in the BMR and the health risk assessment for humans. A total of 30 surface sediment samples were collected and the physicochemical parameters of both water and surface sediments were also measured. The results showed that, the descending order of mean concentrations of heavy metals in the surface sediments of BMR was Fe > Mn > Pb > Zn > Cr > As > Cu > Ni. High accumulation of heavy metals was found in the southern part of the lake, where anthropogenic activities were predominant. In summary, the accumulation and enrichment of heavy metals in the surface sediment of BMR were due to anthropogenic factors such as plantations, logging, sand mining and discharges from fisherman piers.
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    Perlakuan Agresif Ikan Tilapia Merah, Oreocromis Sp.
    (Universiti Sains Malaysia, 1993-04)
    Sa'aid, Hafizah Besar
    Kesan nisbah seks yang berlainan ke atas frekuensi perlakuan agresif dan perlakuan pembiakan ikan tilapia merah, Oreochromis sp. dikaji. Tiada pemerhatian ke atas perlakuan pembiakan boleh dilakukan kerana ikan tidak menunjukkan apa-apa perlakuan pembiakan semasa kaJian dijalankan.
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    Kajian morfologi dan anatomi organ-organ ramenta, anter dan ovari.
    (Pusat Pengajian Sains Kajihayat, Universiti Sains Malaysia, 1996-03)
    Salleh, Muhammad Amin
    dan bunga berdasarkan morfologi dan anatomi. Kajian morfologi ke atas keratan memanjang bunga R. hasse/tii Suringar ini, didapati terdapat struk"tur-struk1.Ur seperti tiub perigon, cuping perigon (petal), diafragma dan kolum turus tengah yang menyokong bahagian-bahagian seperti unjuranunjuran (processes), anter dan ovari. Ramenta pula didapati pada permukaan sebelah da1am diafragma.- l\.fanakala tingkap (window) didapati pada pennukaan cuping perigon, di luar dan dalam ( berdekatan bukaan_ ) diafragma. Pemerhatian melalui mikroskop cahaya bagi sel-sel apek dan tangkai ramenta menWljukkan ia dari jenis parenkima. Pernerhatian anter melalui mikroskop cahaya dan mikroskop elektron pens~ menWljukkan terdapat bijirin debunga di dalam mikrosporangium. Bijirin debunga yang paling matang berbentuk bulat dan licin pada anter peringkat bunga. Manaka1a kajian rnelalui mikroskop cahaya dan mikroskop elel1ron penskanan bagi ovari mentmjukkan terdapat rongga-rongga ovari yang rnengandungi sei-sel gametik dan megaspora pada tunas-tunas dan bunga.
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    Identification and mechanism of anti-Helicobacter pylori alkaloid from Derris trifoliata
    (2011)
    Abd Manaf, Uyub
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    Sulaiman, Shaida Fariza
    Thin layer chromatography on chloroform extract of Derris trifoliata using a so lvent combination of Toluene:Ethyl pcetate: Diethylamine (7: 2: 1) gave five fra ctions and three of them were identified as alkaloids based on the development of brown colour after reacting with Dragendorff's reagent and fluorescing blue and green under UV scan, By column chromatography, these 3 fractions were reevaluated for their action against H. pylori and 13 other pathogen ic bacteria, Two fractions were found to specifica lly inhibit H. pylori wh ile the th ird fraction inhibited 6 other pathogenic bacteria tested and H. pylori, albeit weaker, Two fractions (F1 and F2) were found to specifically inhibit H. pylori wh ile the third fraction (F3) was not specific as it inhbited not only H. pylori but 6 other pathogenic bacteria tested albeit weaker. Toxicity test using brine shrimp assay revealed that LC50 for F1, F2 , F3 and chloroform crude extractwas 8.8 IJg/ml, 966,5 IJg/ml, 60A IJg/ml and 1,1 IJg/ml repectively, suggesting F2 was less toxic with LC50 va lue very close to the limit set at 1000 ug/ml. Batch cu lture and electron microscopic studies revealed that F2 transformed spira ls cells into coccoids as well as directly ki lled them, There was no obvious morphological changes and the action of the compound cou ld probably be inhibition of processes inside the cell. F2 was also tested against 45 clinica l H. pylori isolates to determine its MIC90, This parameter was also determined concurrently for metronidazole, tetracycline and amoxycillin, antibiotics which are commonly used against H, pylori, Ninety-six percent (43/45) of the isolates were metronidazole resistance (MIC>8IJg/ml) wh ich undermines success of treatment in tropica l countries, Although MIC90 for F2 was higher (8-16ug/ml) compared to amoxycillin (0 .24-0A8IJg/ml), it was lower compared to metronidazole (>40lJg/ml) and tetracycline(16-32 IJg/ml), Infact F2 killed all the metronidazole-resistance isolates at 32 IJg/ml, while amoxycillin, tetracycline and metronidazole at the highest concentration used(1 .92, 128, 40 IJg/ml) on ly killed 95%, 95% and 5% of the isolates respectively, F2 was further fractionated into two components, A and B. Both these separated components were still inhibitory again st H. pylori, with B slightly more active based on inhibition zone diameter, LC-MS stud ies revealed that both components were mixtures of several compounds. One major sharp peak at 1.64-2 ,50 min retention time was present in the A component and probable designation was "diphenoxine" based on NIST USA Idatabase. We have no information on the exact identity of F2
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    Impact on environmental assets: The increase of Aedes mosquito populations and the epidemiological implication of dengue viruses.
    (2016)
    Wan Musthapa, Wan Fatma Zuharah
    The aftermath of the flood catastrophe in December 2014 has set up Kelantan as a potential hotbed for mosquito vector distribution and the diseases associated with it. Standing water and poor hygiene practice after flood could provide expansion of mosquito breeding ground, especially Aedes mosquitoes, thus amplifying arbovirus transmission associated with Aedes.