How to translate text using browser tools
1 February 2003 Photostabilization of an Entomopathogenic Fungus Using Composite Clay Matrices
Ephraim Cohen, Tammar Joseph, Frigita Kahana, Shlomo Magdassi
Author Affiliations +

To provide photostabilization for entomopathogenic fungi by anionic dyes, composite matrices based on clay–biopolymer combinations were prepared. In the first step, the negative surface charge of various clays (montmorillonite, attapulgite, bentonite and kaolinite) was reversed to positive by adsorption to the polycationic biopolymer chitosan. The second step involved adsorption of the toxicologically safe anionic dyes fast green (FG) and naphthol yellow S (NYS) to the clay complexes. Compared with cytotoxic photoprotectants like berberine, palmatine and acriflavine, the anionic dyes have no adverse effects up to a concentration of 1 M. In assays using various clay–chitosan–dye matrices and UV irradiation from a lamp source, it was evident that both FG and NYS provided considerable photostabilization for conidia of the entomopathogenic fungus Aschersonia spp. that served as a model biocontrol agent. Apparently, because of the light-dispersing property, bentonite and attapulgite per se provided significant photoprotection. All clay matrices containing FG provided a substantial photostabilization effect.

Ephraim Cohen, Tammar Joseph, Frigita Kahana, and Shlomo Magdassi "Photostabilization of an Entomopathogenic Fungus Using Composite Clay Matrices," Photochemistry and Photobiology 77(2), 180-185, (1 February 2003).<0180:POAEFU>2.0.CO;2
Received: 7 June 2002; Accepted: 1 November 2002; Published: 1 February 2003

This article is only available to subscribers.
It is not available for individual sale.

Get copyright permission
Back to Top