Glucosinolates in alugbati (Basella alba Linn. var. rubra)

Date of Publication

2016

Document Type

Master's Thesis

Degree Name

Master of Science in Chemistry

College

College of Science

Department/Unit

Chemistry

Thesis Adviser

Marissa G. Noel

Defense Panel Chair

Nancy Lazaro-Llanos

Defense Panel Member

Rosario Sagum
Emmanuel V. Garcia

Abstract/Summary

Cancer is currently the third leading cause of mortality in the Philippines. This non-communicable disease is presumed to be lifestyle related and health experts agree that one excellent way for prevention is the consumption of vegetables. From a previous work, it was found that the red stem variety of alugbati (Basella alba Linn. var. rubra) contains glucosinolates sulfur-containing glucosides known for the anticancer activities of some of its hydrolysis products. Another research found that alugbati extracts exhibited cytotoxicity on MCF7 cell lines. These evidences became the provocation for further investigation.

Six previously identified glucosinolates in alugbati were subjected to MS/MS analysis for a more thorough investigation. Nominal masses of the six desulfoglucosinolates were detected and assessed using Index of Hydrogen Deficiency (IHD) and the Nitrogen rule. Five of the six desulfoglucosinolates Sinigrin, mercaptomethyl, glucocheirolin 6-O-sinapoyl-b-D-thioglucoside, benzyl-sulfonylpropenyl and butenyl-thio-heptene were further investigated by proposing possible fragmentation sites and inspecting isotopic distributions.

The development of an optimum procedure for the hydrolysis and extraction was deemed necessary as the objective was to deliver a relatively high yield of desired hydrolysis products which could aid in succeeding chemical analyses and biological assays. Quantitative analysis of total isothiocyanates and their conjugates was done by v carrying cyclocondensation reactions with 1,2-benzenedithiol. The optimum hydrolysis procedure developed was hydrolysis of freeze-dried alugbati using water for 30 minutes, with exogenous enzyme and 1 mL 0.25 mM ascorbic acid. The optimum extraction procedure formulated was a one-time extraction of the alugbatiwater mixture with DCM for 30 minutes. Additionally, qualitative analysis using GCMS provided indirect evidences of the presence of isothiocyanates from alugbati extracts as the cyclocondensation product 1,3-benzodithiole-2-thione was detected.

In order to determine the genotoxicity of alugbati extracts, Comet assay was employed on MCF7 cell lines incubated with alugbati juice and hydrolysate. Alugbati juice (AJ) and hydrolysate (AH), both in DMSO, formed pronounced comet tails indicating that DNA damage had occurred. No significant difference was found between the genotoxic effects of juice and hydrolysate attributable to the possibility of hydrolysis also taking place during the juice extraction. Evidence is also given to indicate that compounds which may be causing DNA damage are more soluble in DMSO than in water. Overall, the findings for this research support those obtained in the preliminary studies on alugbati glucosinolates and affirm significant chemotherapeutic properties of extracts of the plant.

Abstract Format

html

Language

English

Format

Electronic

Accession Number

CDTG006935

Shelf Location

Archives, The Learning Commons, 12F Henry Sy Sr. Hall

Physical Description

1 computer disc ; 4 3/4 in.

Keywords

Glucosinolates; Medicinal plants--Philippines

Upload Full Text

wf_no

This document is currently not available here.

Share

COinS