Isolation and characterization of bioactive sucrose esters from tobacco plant (Nicotiana tabacum L. var. viscaya)

Date

10-2001

Degree

Bachelor of Science in Chemistry

Adviser/Committee Chair

Evelyn B. Rodriguez

Abstract

Rubis, Jesirene del Rosario, University of the Philippines Los Banos. October 2001. Isolation and Characterization of Bioactive Sucrose Esters front Tobacco Plant [Nicotiana tabacum L. var. Viscaya].

Adviser: Dr. Evelyn B. Rodriguez

The polar leaf surface chemicals of young tobacco plant were isolated by dipping the leaves in 70 % isopropyl alcohol and partitioning the concentrated isopropyl alcohol extract between 1:1 80 % aqueous methanol (Me011) — hexanes. The Me0I-I extract was fractionated by open column chromatography using silica gel 60 and gradient elution. Four major fractions (SE III, SE V, SE VI and SE IX) were obtained, which on IR spectroscopic and qualitative chemical analyses proved to be sucrose esters. The other major isolate was a large amount (13.7 g out of 3 kg leaves) of a mixture of crystalline organic acids.

The sucrose esters and the mixture of organic acids were subjected to the golden apple snail (Pomacea canaliculata) contact toxicity assay, the radish (Raphanus sativus) seed germination inhibition assay (petri dish method), and aphid (Aphis gossypii Glover) contact toxicity assay. Results of the snail contact toxicity assay showed that all sucrose ester fractions caused 100.0 % mortality at 250 ppm. However, the most active was SE III, which caused 100.0 % mortality even at 30 ppm. On the other hand, the mixture of organic acids caused 100.0 % mortality only at a high concentration of 2000 ppm. The radish seed germination assay revealed that at 1000 ppm, all sucrose ester fractions and the mixture of organic acids highly inhibited seed germination, allowing only 4.4 % to 16.6 % germination after 48 hours. At 250 ppm, SE V was the most toxic towards aphids, causing 88.5% mortality at 1000 ppm In comparison, the mixture of organic acids caused only 28.3 % aphid mortality at the same concentration.

Language

English

Location

UPLB Main Library Special Collections Section (USCS)

Call Number

Thesis

Document Type

Thesis

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