The isolation and purification of the leaves of Kopsia singapurensisRidl. (Apocynaceae) revealed the presence of steroids, terpenes, and alkaloids. Stigmasterol 1 was isolated from the hexane crude extract of the leaves of this species. This phytochemical study involves extraction, separation by using various chromatographic methods and structural determination by spectroscopic technique such as IR, NMR including 1D-NMR (1H, 13C and DEPT), 2D-NMR (COSY, NOESY, HMQC/HSQC, and HMBC) and GCMS, involving also comparison with data from the literature..

5238 hits

In Malaysia, Alstonia spathulataBl. is locally known as pulai basong which distribute in peat forest. The separations of the chemical components from hexane crude extract (bark) of Alstonia spathulata were carried out using different chromatographic techniques (column chromatography and thin layer chromatography). One compound were isolated and identified as lupeol acetate (1). This compound have never been reported and isolated from this species. The structures of this compound were elucidated based on the basis of detailed 1D-NMR (1H, 13C and DEPT) and 2DNMR (COSY, HSQC, HMBC) spectroscopic analysis. The data analysis was also compared with the literature...

5043 hits

A phytochemical investigation of the bark of Alseodaphne peduncularis (Wall. Ex. Ness) Meissn (Lauraceae) has resulted in the isolation of a known aporphine alkaloid; boldine (1). The isolation and purification of the alkaloids were achieved using column chromatography (CC) and preparative thin layer chromatography (PTLC). The structural elucidation was performed by spectral methods mainly 1D and 2D NMR, IR, UV and MS, and in comparison with data from other literature...

5491 hits

Murraya koenigii (Rutaceae), locally known as curry leaf tree, is a medicinally important herb of Indian origin and now is widely distributed throughout southern Asia. The bark of Malayan Murraya koenigii was investigated for phytochemical content. The isolation of chemical constituents from its hexane extract was carried out by using various chromatographic techniques. Spectroscopic methods, including NMR, IR, UV, MS spectra data, were used for the structural characterization. Four C23-carbazole alkaloids were isolated..

2666 hits

A phytochemical study on the leaf extract of Alseodaphne corneri Kosterm involving extraction, separation by using various chromatographic methods and structural determination by spectroscopic technique such as ultraviolet spectra (UV), infrared spectra (IR), nuclear magnetic resonance (NMR) and mass spectra (MS) was carried out. The isolation and purification from the leaves of Alseodaphne corneri Kosterm yielded two aporphines: norlirioferine and lirioferine...

6067 hits

The flavonoid compound, quarcetin-3-O-rutinoside (1) has been isolated from n-BuOH extract of the fresh of Sao Pedro Petro of Tubers of Cassava (Manihot esculenta Crantz). The chemical structure of compound (1) was identified by spectroscopic data including UV, IR, NMR (1H, 13C, DEPT 135°, HMQC, HMBC, 1H1H COSY) and MS and by comparing with previously reported spectral data.  ..

1399 hits

[No abstract available]..

427 hits

Kajian bertujuan untuk mengenal pasti tahap tekanan kerja, tahap efikasi kendiri akademik dan tahap komitmen meneruskan pengajian dalam Program Pensiswazahan Guru (PPG) di Perlis. Kajian juga mengukur hubungan antara tekanan kerja dengan efikasi kendiri akademik serta mengenal pasti peramal-peramal bagi komitmen meneruskan pengajian. Seramai 150 orang guru telah dipilih secara rawak mudah. Data-data dikutip melalui borang soal selidik yang mengandungi instrumen tekanan kerja Teacher Stress Inventory oleh Fimian, instrumen efikasi kendiri akademik College Student Self Efficacy oleh Landry dan instrumen komitmen meneruskan pengajian yang dibangunkan sendiri oleh pengkaji. Darjah kebolehpercayaan bagi ketiga-tiga instrumen adalah 0.887, 0.861 dan 0.799. Analisis dibuat dengan menggunakan kaedah statistik deskriptif dan statistik inferens iaitu kolerasi Pearson dan regresi berganda Stepwise. Hasil menunjukkan bahawa tekanan kerja pada tahap sederhana (min = 3.1), efikasi kendiri akademik p.....

1315 hits

Semenjak Malaysia (dahulunya dikenali sebagai Tanah Melayu) mencapai kemerdekaan pada tahun 1957, bahasa Melayu telah diisytiharkan sebagai bahasa kebangsaan negara kita. Sebagai bahasa kebangsaan, bahasa Melayu memainkan peranan utama sebagai bahasa rasmi dalam segala urasan pentadbiran negara. Bukan itu sahaja, bahasa Melayu juga mempunyai peranan sebagai bahasa perpaduan, iaitu bahasa komunikasi yang digunakan untuk berhubung di antara mdividu pelbagai kaum di Malaysia. Peranan bahasa Melayu semakin berkembang sebagai bahasa yang dapat menyatupadukan masyarakat yang terdiri daripada pelbagai kumpulan etnik bukan sahaja di Semenanjung Malaysia, malah juga di Sabah dan Sarawak. Selang beberapa tahun kemudian apabila bahasa Melayu dinobatkan sebagai bahasa pengantar pendidikan dalam Akta Pelajaran 1961, kedudukan bahasa Melayu menjadi semakin mantap. Bahasa Melayu telah diangkat sebagai bahasa pengantar utama dalam sistem pendidikan negara yang melibatkan pendidikan di semua peringkat .....

3333 hits

The isolation and purification of the leaves extract of Alseodaphne corneri Kosterm yielded four alkaloids; norisocorydine 1, isocorydine 2, 2-norobamegine 3 and obamegine 4. This phytochemical study involves extraction, separation by using various chromatographic methods and structural determination by spectroscopic technique such as ultraviolet spectroscopy (UV), infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR) including 1D-NMR (1H, 13C and DEPT), 2D-NMR (COSY, NOESY, HMQC/HSQC, and HMBC) and mass spectrometry (MS). The IC50 value of antiplasmodial activity for isocorydine 2 and obamegine 4 are 0.50 μmolL-1 and 0.14 μmolL-1 respectively...

5546 hits