Effect of glucose and incubation temperature on metabolically active Lactobacillus plantarum from dadih in removing microcystin-LR.
Lactobacillus plantarum strains IS-10506 and IS-20506 isolated from Indonesian traditional fermented milk, dadih, were screened for their ability to remove the cyanobacterial toxin microcystin-LR (MC-LR) from aqueous solution (100 microg/L) at 22 and 37 degrees C. The objective was to study the main environmental factors influencing the metabolic activity of L. plantarum in MC-LR removal. Residual MC-LR was quantified using HPLC. Non-viable cells inactivated by boiling or acid showed only low MC-LR removal (<23 %). Viable L. plantarum strain IS-10506 at pH 7, at 22 and 37 degrees C was able to remove MC-LR, 64% and 43%, respectively, after 30 h. Strain IS-20506 at pH 7, at 22 and 37 degrees C removed 92% and 45 %, respectively, after 30 h. At 37 degrees C, the removal of MC-LR was lower than at 22 degrees C. Supplementation with glucose (1%, 2%, and 3%, w/v) resulted in faster and higher removal of MC-LR at 37 degrees C, while at 22 degrees C it did not improve MC-LR removal. In the presence of 1 % glucose, IS-10506 and IS-20506 demonstrated significantly the most efficient removal of 80% and 65% of applied MC-LR, after 25 and 20 h, respectively, at pH 7, 37 degrees C. Viable cells as well as active metabolism play important roles in removing MC-LR. This finding offers new and economical tools for decontaminating microcystin containing water.
Surono
I S
IS
Southeast Asian Ministers of Education Organization-Tropical Medicine and Public Health Network, Regional Center For Community Nutrition, University of Indonesia, 6 Salemba Raya, Jakarta 10430, Indonesia. waspodo@indo.net.id
Collado
M C
MC
Salminen
S
S
Meriluoto
J
J
D000704:Analysis of Variance; D002851:Chromatography, High Pressure Liquid; D004791:Enzyme Inhibitors / Q000378:metabolism*; D005947:Glucose / Q000494:pharmacology*; D007185:Incubators; D048191:Lactiplantibacillus plantarum / Q000187:drug effects* / Q000378:metabolism*; D008387:Marine Toxins; D052998:Microcystins / Q000378:metabolism*; D013549:Sweetening Agents / Q000494:pharmacology*; D018508:Water Purification / Q000379:methods
D004791:Enzyme Inhibitors; D008387:Marine Toxins; D052998:Microcystins; D013549:Sweetening Agents; C057862:cyanoginosin LR; D005947:Glucose