The development of a biosensor for the detection of PS II herbicides using green microalgae

A PS II biosensor was developed using intact green algae of Chlorophyta. The biosensor was based on the ability of some herbicides (PS II herbicides) residue to inhibit the binding niche of primary electron donor/acceptor of Photosystem II, plastoquinone B (Os) at 01 heterodimer protein, causing an...

Full description

Saved in:

Bibliographic Details
Main Author:	Maizatul Suriza Mohamed
Format:	Thesis
Language:	English English
Published:	2006
Subjects:	R858-859.7 Computer applications to medicine Medical informatics
Online Access:	https://eprints.ums.edu.my/id/eprint/10111/1/24%20PAGES.pdf https://eprints.ums.edu.my/id/eprint/10111/2/FULLTEXT.pdf
Tags:	Add Tag No Tags, Be the first to tag this record!

id	my-ums-ep.10111
record_format	uketd_dc
spelling	my-ums-ep.101112024-02-15T02:14:58Z The development of a biosensor for the detection of PS II herbicides using green microalgae 2006 Maizatul Suriza Mohamed R858-859.7 Computer applications to medicine. Medical informatics A PS II biosensor was developed using intact green algae of Chlorophyta. The biosensor was based on the ability of some herbicides (PS II herbicides) residue to inhibit the binding niche of primary electron donor/acceptor of Photosystem II, plastoquinone B (Os) at 01 heterodimer protein, causing an increase of the chlorophyll fluorescence. Herbicideinduced chlorophyll-a fluorescence was correlated with the corresponding herbicide concentration to obtain a standard calibration curve for herbicide detection. The fluorescence yield was expressed as a rate of the fluorescence increase calculated mathematically from fitted curve of herbicide-induced fluorescence data using SigmaPlot and CurveFit Expert software. The fluorescence was recorded using a TD-700 fluorometer from Turner Design, USA. Six freshwater microalgae isolated from a lake near Likas Bay, Kola Kinabalu, Sabah were examined; Chlorella sp., Pediastrum sp., Kirchneriel/a sp., Coe/astrum sp., Scenedesmus dimorphus, and Selenastrum sp. Of all the species examined, Scenedesmus dimorphus was found to be the most suitable algae as a biosensor based on the following criteria; (1) highest growth rate, (2) easy to culture and maintain purity, and (3) sensitivity to low concentration of herbicide. Effects of culture age, temperature, solvents, sample matrix and pre-incubation of sample were examined to optimize the biosensor. Cell suspension at 14- days was found to be the best algal age especially when using Scenedesmus dimorphus. The correlations between fluorescence yields (expressed as the rate of fluorescence, {3) and concentration (a) of diuron, propanil and bromaci/ were a = 10A ((log {3- 0.536)/1.08), a = 10''-((log {3- 0. 3893 )/1. 1119) and a = 1 0"((log {3 - 0. 1678)/0. 7084), respectively. The detection range of diuron, propanil and bromacil were 1x1U3 mM - 1mM, 1x10-1 mM - 1 x101 mM and 1x10-1 mM - 1 x1a2 mM, respectively. The lowest detectable concentration of the biosensor was approximately 1 x 1 o-3 mM (2.33x1a2 μg/L), for diuron, 1x10-1 mM (2. 18x1a3 μg/L) for propanil and 1x1a1 mM (2.61x1d3 μg/L) bromacil. The biosensor can be used as an early warning system at present and offers a potential rapid, cheap and fast method for PS II herbicides detection in the future. 2006 Thesis https://eprints.ums.edu.my/id/eprint/10111/ https://eprints.ums.edu.my/id/eprint/10111/1/24%20PAGES.pdf text en public https://eprints.ums.edu.my/id/eprint/10111/2/FULLTEXT.pdf text en validuser masters Universiti Malaysia Sabah School of Science and Technology
institution	Universiti Malaysia Sabah
collection	UMS Institutional Repository
language	English English
topic	R858-859.7 Computer applications to medicine Medical informatics
spellingShingle	R858-859.7 Computer applications to medicine Medical informatics Maizatul Suriza Mohamed The development of a biosensor for the detection of PS II herbicides using green microalgae
description	A PS II biosensor was developed using intact green algae of Chlorophyta. The biosensor was based on the ability of some herbicides (PS II herbicides) residue to inhibit the binding niche of primary electron donor/acceptor of Photosystem II, plastoquinone B (Os) at 01 heterodimer protein, causing an increase of the chlorophyll fluorescence. Herbicideinduced chlorophyll-a fluorescence was correlated with the corresponding herbicide concentration to obtain a standard calibration curve for herbicide detection. The fluorescence yield was expressed as a rate of the fluorescence increase calculated mathematically from fitted curve of herbicide-induced fluorescence data using SigmaPlot and CurveFit Expert software. The fluorescence was recorded using a TD-700 fluorometer from Turner Design, USA. Six freshwater microalgae isolated from a lake near Likas Bay, Kola Kinabalu, Sabah were examined; Chlorella sp., Pediastrum sp., Kirchneriel/a sp., Coe/astrum sp., Scenedesmus dimorphus, and Selenastrum sp. Of all the species examined, Scenedesmus dimorphus was found to be the most suitable algae as a biosensor based on the following criteria; (1) highest growth rate, (2) easy to culture and maintain purity, and (3) sensitivity to low concentration of herbicide. Effects of culture age, temperature, solvents, sample matrix and pre-incubation of sample were examined to optimize the biosensor. Cell suspension at 14- days was found to be the best algal age especially when using Scenedesmus dimorphus. The correlations between fluorescence yields (expressed as the rate of fluorescence, {3) and concentration (a) of diuron, propanil and bromaci/ were a = 10A ((log {3- 0.536)/1.08), a = 10''-((log {3- 0. 3893 )/1. 1119) and a = 1 0"((log {3 - 0. 1678)/0. 7084), respectively. The detection range of diuron, propanil and bromacil were 1x1U3 mM - 1mM, 1x10-1 mM - 1 x101 mM and 1x10-1 mM - 1 x1a2 mM, respectively. The lowest detectable concentration of the biosensor was approximately 1 x 1 o-3 mM (2.33x1a2 μg/L), for diuron, 1x10-1 mM (2. 18x1a3 μg/L) for propanil and 1x1a1 mM (2.61x1d3 μg/L) bromacil. The biosensor can be used as an early warning system at present and offers a potential rapid, cheap and fast method for PS II herbicides detection in the future.
format	Thesis
qualification_level	Master's degree
author	Maizatul Suriza Mohamed
author_facet	Maizatul Suriza Mohamed
author_sort	Maizatul Suriza Mohamed
title	The development of a biosensor for the detection of PS II herbicides using green microalgae
title_short	The development of a biosensor for the detection of PS II herbicides using green microalgae
title_full	The development of a biosensor for the detection of PS II herbicides using green microalgae
title_fullStr	The development of a biosensor for the detection of PS II herbicides using green microalgae
title_full_unstemmed	The development of a biosensor for the detection of PS II herbicides using green microalgae
title_sort	development of a biosensor for the detection of ps ii herbicides using green microalgae
granting_institution	Universiti Malaysia Sabah
granting_department	School of Science and Technology
publishDate	2006
url	https://eprints.ums.edu.my/id/eprint/10111/1/24%20PAGES.pdf https://eprints.ums.edu.my/id/eprint/10111/2/FULLTEXT.pdf
_version_	1794022670654767104

The development of a biosensor for the detection of PS II herbicides using green microalgae

Similar Items