Bioassay Guided Isolation Of Antitermite Compounds From The Bark Of Rhizophora Apiculata

Serbuk kulit kayu Rhizophora apiculata pada mulanya diekstrak dengan petroleum eter (PE) dan metanol. Ekstrak metanol dalam bentuk larutan akueus telah diekstrak semula ke dalam pecahan kloroform (CE), etil asetat (EE) dan n-butanol (BE). Pengasingan berpandukan ujian makmal (ASTM D3345-74) telah...

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Bibliographic Details
Main Author: Kong , Nein Hing
Format: Thesis
Language:English
Published: 2009
Subjects:
Online Access:http://eprints.usm.my/41274/1/Kong_Nein_Hing.pdf
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Summary:Serbuk kulit kayu Rhizophora apiculata pada mulanya diekstrak dengan petroleum eter (PE) dan metanol. Ekstrak metanol dalam bentuk larutan akueus telah diekstrak semula ke dalam pecahan kloroform (CE), etil asetat (EE) dan n-butanol (BE). Pengasingan berpandukan ujian makmal (ASTM D3345-74) telah dijalankan dengan mempertimbangkan kehilangan berat kayu minimum (LWL). Aktiviti anti anai-anainya (ATA) adalah EE>CE>PE>BE, LWLEE = 10.54% pada 500 ppm. Secara perbandingan, kawalan telah haus dimakan. Fraksi-fraksi EE menunjukkan ATA dalam turutan F2>F3>F1, LWLF2 = 5.53%. Analisis kimia dan spektroskopi menentukan asid fenolik adalah komponen aktif dalam EE. Fraksi F2 seterusnya diekstrak dengan kaedah asid-bes (pH ~3) dan hasilnya dikromatografkan. Sifat-sifat kimia dan biologi tidak berubah selepas pemisahan dan ATAnya adalah F2AII>F2AIII>(F2R≈F2AI), LWLF2AII, F2AIII = 6.86, 9.12%. The powdered bark of Rhizophora apiculata was initially extracted with petroleum ether (PE) and methanol. The aqueous methanol extract was re-extracted into chloroform (CE), ethyl acetate (EE) and n-butanol (BE). Bioassay (ASTM D3345-74) guided fractionation was carried out on the basis of the least wood loss (LWL). The anti-termite activity (ATA) was in the order of EE>CE>PE>BE, LWLEE = 10.54% at 500 ppm. In contrast, controls were severely damaged. Fractions of EE showed ATA in the order of F2>F3>F1, LWLF2 = 5.53%. Chemical and spectral studies proposed that the active compounds in EE were of phenolic acids. Fraction F2 was then partitioned into aqueous and organic layers at pH ~3 and the organic residue was subjected to chromatographic separation. The chemical and biological properties of the F2 fractions were not altered and the ATA sequence was F2AII>F2AIII>(F2R≈F2AI), LWLF2AII, F2AIII = 6.86, 9.12%.