US EPA

7447038 

Journal Article 

Co-occurrence of microcystin- and geosmin-producing cyanobacteria in the Tri An Reservoir, a drinking-water supply in Vietnam 

Thanh-Luu Pham; Thi Hoang Yen Tran; Nghia Son Hoang; Xuan Quang Ngo; Thai Thanh Tran 

2020 

Yes 

Fundamental and Applied Limnology
ISSN: 1863-9135
EISSN: 2363-7110 

Gebruder Borntraeger Verlagsbuchhandlung 

193 

4 

299-311 

English 

10.1127/fal/2020/1296 

WOS:000543753800002 

The present study aimed to investigate the occurrence and distribution of microcystin-(MC) and ge-osmin-producing cyanobacteria in the Tri An Reservoir, a drinking-water supply in Southern Vietnam. The MC concentration was measured using high-performance liquid chromatography (HPLC). Geosmin production was screened using headspace solid-phase microextraction (HPME) and gas chromatography/mass spectrometry (GC/ MS). The ability of cyanobacteria to produce MC and geosmin was determined by the presence of two molecular markers: mcyA and geoA, respectively. A maximum MC concentration of 207.6 ± 14.2 µg g–1 dry weight (DW) was detected from an isolated Microcystis aeruginosa (Kützing) (strains TAMA1), and the maximum geosmin concentration of 114.2 ± 6.1 ng g–1 wet weight (WW) was detected from an isolated Dolichospermum circinale (Rabenhorst) (strains TADC4); MC and geosmin were also observed in water-bloom samples, with the highest concentrations being 463.6 ± 34.7 µg g–1 DW and 148.5 ± 9.8 ng g–1 WW, respectively. These results represent the first molecular evidence of the co-occurrence of MC-and geosmin-producing cyanobacteria in a drinking-water-supply reservoir in Vietnam. Given the success of the molecular techniques and chemical analysis used, we propose that multiplex polymerase chain reaction assays, HPLC, and HPME GC/MS can be reliable tools for investigating MC and geosmin in water-bloom and cyanobacterial samples. Further, we propose that they can be used to create early-warning systems for harmful secondary metabolites produced by cyanobacteria in drinking-water supplies. © 2020 E. Schweizerbart’sche Verlagsbuchhandlung, Stuttgart, Germany. 

taste and odor; off-flavor compound; earthy/muddy smell; cyanotoxin