Biotreatment of Melanoidin-Containing Distillery Spent Wash Effluent by Free and Immobilized Aspergillus oryzae MTCC 7691

Water Air Soil Pollut (2013) 224:1755 DOI 10.1007/s11270-013-1755-2

Biotreatment of Melanoidin-Containing Distillery Spent Wash Effluent by Free and Immobilized Aspergillus oryzae MTCC 7691

M. N. Chavan & N. D. Dandi & M. V. Kulkarni &

A. B. Chaudhari

Received: 15 March 2013 /Accepted: 16 September 2013 /Published online: 3 October 2013 # Springer Science+Business Media Dordrecht 2013

Abstract A total of three fungal isolates from samples collected at spent wash disposal area were screened for their ability to degrade melanoidin. Distillery molasses spent wash was decolorized, and its chemical oxygen demand (COD) was reduced in immobilized fungal bioreactor (IFB) in the absence of carbon and nitrogen source using fungal mycelia of Aspergillus oryzae MTCC 7691. Fungal mycelia immobilized on baggase packed in a glass column under a batch-wise mode (1) effected removal of 75.710.12 % color, 51.00.13 % biological oxygen demand (BOD), 86.192.56 % COD, and49.00.12 % phenolic pigments of distillery spent wash up

to 25 days at 30 C, while free fungal mycelia resulted in removal of 63.10.16 % color, 27.740.14 % BOD,76.211.62 % COD, and 37.320.17 % phenolic pigments of distillery spent wash using shake flask, (2) manganese peroxidase (MnP) activity was highest (1.55 0.01 U ml1 min1) in immobilized fungi, followed by lignin peroxidase (0.650.01 U ml1 min1) and laccase activity (0.90.01 CU ml1 min1), (3) accumulative MnP activity was highly correlated with (r=0.9216) spent wash decolorization and (r=0.7282) reduction of phenolic pigments, suggesting the presence of MnP activities in bioremediation of spent wash and (4) degradation of spent wash was confirmed by high-performance thin layer chromatography and gas chromatographymass spectrometry analysis. Measurement of chlorophyll a content of Chlorella species cultivated on treated spent wash effluent obtained from immobilized fungal bioreactor was5.160.71 g ml1 compared with 1.3060.017 g ml1 obtained with untreated spent wash. Thus, this work may provide a reasonable alternative for cost-effective bioremediation of distillery spent wash using immobilized A. oryzae on baggase fibers.

Keywords Aspergillus oryzae MTCC 7691 . Bagasse . Bioreactor . Decolorization . GC-MS . Immobilization

1 Introduction

The steep increase in the demand for alcohol in the world market as a basic chemical commodity promoted its extensive production by cane-molasses-based distilleries.

M. N. Chavan and N. D. Dandi contributed equally to this study as first authors