Decolorization of molasses wastewater by yeast strain, Issatchenkia orientalis No. SF9-246.
Among 2,402 strains of yeast isolated from various sources in Thailand, a strain No. SF9-246 identified as Issatchenkia orientalis, showed the highest potential for use in decolorization of molasses wastewater. In a malt extract-glucose-peptone broth (MYGP) culture containing melanoidin pigment (MP) at 30 degrees C a 60.2% decolorization was obtained within 7 days. The strain appeared to enhance both MP-degradation and MP-adsorption. The strain showed MP, chemical oxygen demand (COD) and biological oxygen demand (BOD(5)) removal efficiencies of 91.2%, 80.0% and 77.4%, respectively from anaerobic-treated molasses wastewater solution (T-MWW), collected from an anaerobic pond. The wastewater contained 2.5% glucose, 0.1% NH(4)Cl, and 0.1% KH(2)PO(4). The pH was adjusted to 5.0 at 30 degrees C for 7 days batch type culture system. The strain showed almost constant decolorization yield of 75-80% over 7 days in a periodical feeding system of 10% fresh T-MWW with the culture system. The strain provided a constant decolorization yield about 70% during 3 replacement cycles. Gel filtration chromatography showed that larger molecular weight fraction of MP solution was rapidly removed, while the smaller molecular weight fraction remained in the effluent.
Tondee
Tusanee
T
Department of Environmental Technology, School of Energy, Environment and Materials, King Mongkut's University of Technology Thonburi (KMUTT), Thonkru, Bangmod, Bangkok 10140, Thailand.
Sirianuntapiboon
Suntud
S
Ohmomo
Sadahiro
S
D001203:Ascomycota / Q000378:metabolism; D005505:Food Coloring Agents / Q000032:analysis; D007220:Industrial Waste; D008965:Molasses; D010101:Oxygen Consumption; D011108:Polymers / Q000032:analysis*; D014865:Waste Disposal, Fluid; D018508:Water Purification
D005505:Food Coloring Agents; D007220:Industrial Waste; D011108:Polymers; C011908:melanoidin polymers