Open AccessON THE USE OF FROTH FLOTATION IN THE RECOVERY OF Bacillus sphaericus SPORES
Author(s) -
E.M.M.M. Rios,
Carlos Edison Lopes,
Francisca Pessôa de França
Publication year - 1997
Publication title -
brazilian journal of chemical engineering/brazilian journal of chemical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.313
H-Index - 52
eISSN - 1678-4383
pISSN - 0104-6632
DOI - 10.1590/s0104-66321997000200004
Subject(s) - bacillus sphaericus , spore , larvicide , chemistry , population , food science , biology , botany , bacillales , larva , bacteria , bacillus subtilis , aedes aegypti , genetics , demography , sociology
Abstract - The recovery of Bacillus sphaericus strain 2362 spores from fermented medium by batch flotation was tested under different conditions. Flotation kinetic studies were performed at 800 rpm and 3 l air/min. The pH values were adjusted at the following set of values: 5.0, 7.0 and 9.0. The results showed that the spore removal rate is influenced by the pH value. At pH equal to 5.0 we observe an adverse effect on the spore concentrate obtention. In this situation the maximum value of the concentration factor was 1.4 when the recuperation percentage was 99%. At pH equal to 7.0 the concentration factor reached the highest value, 7.0, but the recuperation percentage stayed around 96%. Field experiments with the floated material demonstrated that its larvicide activity was sufficient to keep a Culex quinquefasciatus larvae population under control at in a breeding site, during 3 months with 2 application