Pusat Penyelidikan Dadah dan Ubat-Ubatan - Tesis
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- PublicationChemical Constituents And Cytotoxocity Of The Stem Bark Calophyllum Lanigerum Var. Austrocoriaceum (Whitemore) P. F. Stevens And Calophyllum Andersonii P. F. Stevens(2024-04)Mokhtar, NorishaPlants from the genus Calophyllum, have gained the interest of phytochemists due to the exciting new discoveries of its bioactive constituents. Phytoconstituents such as coumarins, chromanones, xanthones, and triterpenoids are frequently discovered phytochemical groups in this genus. These phytochemicals proven to possess potential pharmacological importance that are essential for scientists to subject it in pharmacotherapeutic applications in treating targeted diseases. For example, used for pharmacotherapeutic purpose in treating HIV, cancer, and inflammatory related diseases. In this study, the stem bark of Calophyllum lanigerum and Calophyllum andersonii were investigated by extracting, isolating, and characterising the possible phytochemicals that present and assessing their cytotoxic activity, respectively. Five phenolics and two triterpenoids have been isolated from the stem bark of C. lanigerum. The phenolic compounds were identified as caloteysmannic acid (A), isocalolongic acid (B), calolongic acid (C), euxanthone (D), calanone (E), and two common triterpenoids, friedelin (F) and stigmasterol (G). Meanwhile, calanone (E) and its constitutional isomer, isocalanone (H) together with soulattrolide (I) and friedelin (F) were isolated from the stem bark of C. andersonii. Chromanone acids (Compounds A and B) were reported for the first time in C. lanigerum in Sarawak region. The chemical structures of these isolated compounds were elucidated using detailed spectroscopic techniques including NMR (1D, 2D), MS, UV-Vis, FTIR. Extracts (n- xxi hexane, chloroform, ethyl acetate) and compounds (A, B, E, and H) from both Calophyllum species were subjected for their cytotoxicity against HeLa Chang liver (human cervix carcinoma) and HL-7702 (human normal liver) cell lines. Only ethyl acetate extract from C. lanigerum exhibited promising cytotoxicity, with IC50 value of 34.13 ± 3.82 μg/mL, while n-hexane and chloroform extracts showed moderate cytotoxicity against Hela Chang liver cell line [IC50: 93.84 ± 9.35 μg/mL and 81.33 ± 2.41 μg/mL, respectively]. The observed cytotoxic effects of the ethyl acetate extract suggest its potential for further development as an anticancer agent.
- PublicationPhytochemical Studies And Cytotoxicity Assessment Of Stem Bark Extracts From Calophyllum Macrocarpum Hook. F. And Calophyllum Recurvatum P. F. Stevens(2024-04)Firouz, Noor SyarafanaNumerous Calophyllum sp. have long been valued widely in Asian traditional medicine especially in Malaysia. The modern natural product-based research on the genus Calophyllum has further revealed a variety of biological functions exhibited by these plants, such as inhibition of HIV, antioxidant, and cytotoxicity. Species from the genus Calophyllum are also abundant in phenolic compounds especially xanthones and coumarins. However, Calophyllum macrocarpum and Calophyllum recurvatum are among the species that still need more scientific documentation on the phytochemistry and pharmacological aspects. In this research project, the stem bark of Calophyllum macrocarpum and Calophyllum recurvatum were being subjected for phytochemical investigation, which led to the isolation of various phytochemicals such as xanthones and coumarins. Extensive chromatographic separations and purifications on the stem bark of C. macrocarpum (n-hexane and chloroform extracts) resulted in isolation of prenylated xanthones; ananixanthone (1), trapezifolixanthone (2), 8-deoxygartanin (3), as well as triterpenoid; stigmasterol (4) and friedelin (5). Furthermore, thwaitesixanthone (6), teysmanone A (7), soulattrolide (8), calanone (9), as well as friedelin (5) were successfully being isolated from the stem bark of C. recurvatum (n-hexane and chloroform extracts).
- PublicationPhytochemistry Of Calophyllum Havilandii P.F. Stevens And Calophyllum Lowei Planch. & Triana And Their Biological Activities(2024-07)Zailan, Ahmad Alif DanialPlants from the genus Calophyllum (Calophyllaceae) is a treasure trove of various interesting phytochemicals with impressive structural diversity. These phytochemical constituents were often discovered as derivatives in the classes of phenolics, such as xanthones, coumarins, chromanones, phloroglucinols, and flavonoids. Many of them are proven to exhibit wide range of pharmacological as well as biological activities, such as cytotoxic, anti-viral, anti-inflammatory, and anti-microbial. In this study, the process of extraction, isolation, and characterization of phytochemicals were conducted on the stem bark of two endemic Malaysian Calophyllum species from Sarawak, namely Calophyllum havilandii and Calophyllum lowei. All of the isolated phytochemicals were characterized and elucidated using extensive spectroscopic techniques such as MS, IR, UV, and NMR.
- PublicationSatu Kajian Ke Atas Penglibatan Remaja Dalam Masalah Penyalahgunaan Dadah Dan Ketum (Mitragyna Speciosa) Di Malaysia(2024-09)Suhaimi, Mohd Aizuddin AzuanNational Anti-Drug Agency (AADK) found most of the newly detected adolescent drug users were engaged in unsafe sexual behaviours and abusing ketum (Mitragyna speciosa) in the country. While they remain unapproachable and given the paucity of studies involving them, this mixed-method, cross-sectional study aims to investigate the risky sexual behaviours and motives of ketum use. A total of 80 adolescents (age between 13 and 19 years) who were undergoing mandatory drug rehabilitation under Section 6 of the Drug Dependants (Treatment and Rehabilitation) Act of 1983 were recruited through purposive sampling from two formal rehabilitation centres (PUSPEN). All the study data was collected with a self-administered, semi-structured questionnaire, while 21 respondents also participated in the in-depth, face-to-face interviews. Majority were males (70%, n=56/80), only 24 respondents were females. Most Malays (96%, n=77/80), while the samples mean age was 18.2 years (SD=1.40). Sixty-three percent (n=50/80) used methamphetamine only, and the samples mean duration of drug use was 3.15 years (SD=1.5). Sixty-nine percent had engaged in sex previously. High-risk sexual behaviours include having unprotected sex (11%), sex with more than one person (84%), and sex under the influence of drugs (94%). About 44% of the sample had intimate partners who use drugs. Most respondents (64%) were aware of the advantages of safe sex and were familiar with HIV transmission modes (74%). Results from multivariate logistic analysis indicate that females had significantly higher odds of engaging in unprotected sex and having intimate partners who use drugs, whereas, males were, however, more likely to have sex under the influence of drugs.
- PublicationDiscovery Of New Potential Pyrido[2,3-D]Pyrimidin-7-One Based Cdk4 Inhibitors Using Molecular Modelling Approaches(2023-02)Al Attraqchi, Omar Husham AhmedCyclin-dependent kinases (CDKs) are a class of regulatory enzymes that modulate various biochemical properties of the cell such as cell division. Different CDK enzymes have been shown to be promising biological targets for combating different types of cancer. In particular, the CDK4 enzyme has been observed to be overexpressed in several types of cancer including breast cancer. The usage of small-drug molecules that inhibits the activity of the CDK4 enzyme has proved to be clinically valid approach. However, currently available solutions suffer from various limitations such as insufficient activity. Among the most notable inhibitors of the CDK4 enzyme are the compounds based on the pyrido[2,3-d]pyrimidin-7-one scaffold. In this study, computer-aided drug design (CADD) methods including ligand-based and structure-based methods have been applied on the compounds derived from this scaffold. The applied CADD methods revealed the correlation of the physicochemical properties with the activity and gave insights into the binding process. The used ligand-based CADD methods included quantitative structure-activity relationship (QSAR) and pharmacophore modeling.