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26 record(s) found

Two New isoquinoline alkaloids from the bark of Alphonsea cylindrica King and their antioxidant activity

Abstract

Two new isoquinoline alkaloids, iraqiine (1) and kareemine (2), along with five known alkaloids, muniranine (3), kinabaline (4), O-methylmoschatoline (5), atherospermidine (6) and N-methylouregidione (7), were purified from the dichloromethane crude extract of Alphonsea cylindrica bark. The structures of these compounds were elucidated through extensive 1D and 2D NMR, IR and LC–MS studies and comparison with previously reported data. Compounds (1–5 and 7) were tested for their antioxidant activity using in vitro DPPH radical scavenging assay, and 1, 3 and 4 showed the highest antioxidant activities with IC50 values of 48.77 ± 1.01, 44.51 ± 1.12 and 64.28 ± 0.93 μg/ml, respectively ..

Article Published 2019 5289 hits Limited

Content is king: Malaysian industry experts point of view on local content for mobile phones

Ariffin Shamsul Arrieya, Dyson Laurel Evelyn, McKenzie Darlene Hoskins,

Article Published 2012 2084 hits Available

Identification of major and minor allergens of Black Tiger Prawn (Penaeus monodon) and King Prawn (Penaeus latisulcatus)

Sahabudin Syuhaidah, Misnan Rosmilah, Mohammad Yadzir Zailatul Hani, Mohamad Jamaludin,

Abstract

Background: Prawns and shrimp are a frequent cause of seafood allergy mediated by IgE antibodies. Penaeus monodon and Penaeus latisulcatus, commonly known as black tiger prawn and king prawn, respectively, are among the most frequently consumed prawns in Malaysia. The aim of thi s study was to identify the IgE-binding proteins of these 2 prawn species. Methods: Raw and boiled prawn extracts were prepared and then resolved by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). IgE-immunoblotting was then performed using sera from patients with positive skin prick tests to the raw prawn extracts. Results: SDS-PAGE analysis of the raw extracts of both prawn species revealed 23 protein bands; the boiled extracts yielded fewer protein bands. The bands in the range of 40 to 100 kDa were sensitive to heat and therefore were not found in the boiled extracts. Immunoblot of raw extracts of black tiger prawns and king prawns yielded 14 and 11 IgE-binding proteins, respectively,.....

Article Published 2011 2156 hits Available

Cytotoxic and Xanthine Oxidase Inhibitory Activities of Chemical Constituents of Alphonsea cylindrica King

Yuhanis Mhd Bakri

Abstract

This study aimed to investigate the chemical constituents from Alphonsea cylindrica as well as their cytotoxic and xanthine oxidase inhibitory activities. The chemical compounds were isolated and purified by various chromatographic techniques and their structures were elucidated via modern spectroscopic techniques including NMR, MS, IR, UV and comparison with literature. A study on the barks of A. cylindrica has found eleven known compounds were identified as stigmasterol (1), isoursuline (2), cyathocaline (3), kinabaline (4), muniranine (5), isooncodine (6), iraqiine (7), O-methylmoschatoline (8), kareemine (9), atherospermidine (10) and N-methylouregidione (11). The cytotoxic effect of hexane, DCM and methanol of bark of A. cylindrica as well as the isolated compounds; 1, 2, 3, 4, 5, 7, 8, 9 and 10 were estimated on MCF-7 human breast cancer cells and isoursuline possessed the most potent inhibitory activity with IC50 value of 33 µg/ml. Eight compounds 1, 3, 4, 5, 6, 8, 10 and 11 di.....

Article Published 2019 1242 hits Available

Chemical composition of the essential oil of diospyros wallichii king & gamble (Ebenaceae)

Wan Mohd Nuzul Hakimi Wan Salleh

Abstract

The chemical composition of the essential oil from the leaves of Diospyros wallichii (Ebenaceae) growing in Malaysia was investigated for the first time. The essential oil was obtained by hydrodistillation and fully characterized by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). A total of 34 components (95.8%) were successfully identified in the essential oil which were characterized by high proportions of β-eudesmol (28.5%), caryophyllene oxide (9.5%), β-caryophyllene (7.2%), α-eudesmol (6.5%) and germacrene D (6.2%). ..

Article Published 2020 643 hits Available

Isolation of a morphinan alkaloid and a methoxybenzoic acid with the investigation on the antibacterial effect of alphonsea cylindrica king leaves

Tan, Siow-Ping

Abstract

Alphonsea cylindrica King belongs to the family Annonaceae, which is traditionally used to treat rheumatism, bruises, and edema. Investigation of its antibacterial properties was carried out on hexane and dichloromethane crude extracts using agar diffusion method and minimum inhibitory concentration against ESKAPE pathogens. Both extracts showed positive results in inhibiting E. faecium, S. aureus, and K. pneumoniae, while the dichloromethane extract showed further inhibition against P. aeruginosa. A morphinan alkaloid, O-methylpallidinine (1), along with a methoxybenzoic acid, isovanillic acid (2), were isolated from the dichloromethane leaf extract of the plant and elucidated via NMR spectroscopy, FTIR spectroscopy, UV-vis spectroscopy, and GC-MS, and compared with the reported data. Both compounds are reported for the first time from A. cylindrica, while O-methylpallidinine was isolated as natural product for the first time from the family Annonaceae. Both 1 and 2 showed low activit.....

Article Published 2021 1698 hits Available

Keberkesanan pembelajaran inovatif secara atas talian di Universiti Pendidikan Sultan Idris Tanjong Malim Perak, Malaysia

Hong, Betty King Ching

Abstract

Perubahan pola pembelajaran pada masa ini secara besar-besaran di semua peringkat pendidikan akibat pandemik COVID-19. Kajian ini telah dijalankan bagi tujuan untuk mengenal pasti sama ada berkesan atau tidak terhadap pembelajaran inovatif secara atas talian dalam mahasiswa dan mahasiswi sem 7 bagi program Ijazah Sarjana Muda Pendidikan (Pendidikan Jasmani) Dengan Kepujian di Universiti Pendidikan Sultan Idris, Perak. Reka bentuk kajian ini adalah kuantitatif dan soal selidik diedarkan secara rawak melalui Google Form kepada sampel kajian yang dipilih berdasarkan Krejcie dan Morgan (1970) iaitu memerlukan sekurang-sekurang 52 sampel untuk menjawab daripada 59 populasi sampel. Nilai pekali kesahan bagi soal selidik ini ialah 1.00 dan nilai kebolehpercayaan ialah 0.77. Soal selidik ini mengandungi 35 soalan yang terdiri daripada 5 bahagian yang berbeza. Microsoft Excel digunakan untuk mengumpul data dan menganalisis data bagi mengira min, sisihan piawai, frekuensi dan peratusa.....

Final Year Project Published 2023 2703 hits Available

Acetylcholinesterase activity of crude extracts and flavonoids from Artocarpus anisophyllus Miq. and Artocarpus lowii King

Siti Awanis Abdullah

Abstract

A flavonoids-rich extract and seven flavonoids from the leaves and heartwoods of A. anisophyllus Miq. and A. lowii King were investigated for their inhibitory effects against acetylcholinesterase enzyme. The flavonoids were fully characterized spectroscopically as artocarpin (1), isobavachalcone (2), pyranocycloartobiloxanthone A (3), 5,7-dihydroxy-4'-methoxy-6-prenylflavanone (4), 5-hydroxy-7,8-(2,2-dimethylchromano)-4'-methoxy-flavanone (5) 4',5-dihydroxy-6,7-(2,2-dimethylpyrano)-2'-methoxy-8-γ,γ-dimethylallylflavone (6) and 2',4'-dihydroxy-3,4-(2",2"-dimethylchromeno)-3'-prenyldihydrochalcone (7). Acetylcholinesterase inhibitory activity of the samples was determined using TLC plate with bioactivity staining based on the Ellman’s method. Pyranocycloartobiloxanthone A (3) exhibited an excellent inhibitory activity with detection limit at 7.81 μg/mL...

Article Published 2022 595 hits Available

Teaching Arabic for medical professionals (A book published by King Saud University-1997) (Survey, analytical and evaluative study)

Muhammad,Mutasim Yousuf Mustafa

Abstract

This research paper comes in three parts, the first of which deals with the emergence of language teaching (any language) for specific purposes, the justification of that emergence, the terminology that appears in the folds of this research paper, the difference between teaching Arabic language for specific purposes and teaching it for general purposes, and authorship literature in the field of teaching Arabic for specific purposes. The second part of these parts analyzes the book (Arabic for medical professionals) issued by King Saud University 1997.As for the last part. It discusses the evaluation of the book in the light of the conceptual frameworks of writing books for teaching languages for specific purpose. The research paper ends up with its findings and recommendations. Keywords: Medical professionals - Specific purpose – Teaching- Terminology- Literature..

Article Published 2022 510 hits Available

Chemical composition and anticholinesterase inhibitory activity of essential oils from Magnolia villosa (Miq.) H.Keng. and Magnolia maingayi King. Leaves

Wan Mohd Nuzul Hakimi W Salleh

Abstract

This study aimed to investigate the chemical compositions of the leaf essential oils of Magnolia villosa (Miq.) H. Keng. and M. maingayi King. growing in Malaysia. The leaf essential oils were obtained by hydrodistillation and fully characterized by gas chromatography and gas chromatography-mass spectrometry. Analysis of M. villosa and M. maingayi leaf essential oils resulted in 96.4% and 98.7% of the total essential oil, respectively. The main components of M. villosa leaf essential oil were ?-caryophyllene (32.8%) and ?-humulene (8.8%), while in M. maingayi leaf essential oil gave ?-elemene (27.4%), ?-caryophyllene (16.4%), and (E)-nerolidol (14.4%). Anticholinesterase inhibitory activity was also evaluated using acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory assays. M. villosa leaf essential oil revealed a moderate inhibitory effect on AChE (percentage inhibition, I%: 62.5%) and BChE (I%: 74.8%) at a concentration of 1,000 ?g/mL. In conclusion, the leaf esse.....

Article Published 2023 379 hits Available

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