|
Enhancement
of microalgal production through bacterial mineralization of ethylene glycol
M.
Kishi1*, M. Kawai1, K. Tsuchiya2, M. Koyama3,
N. Nagao4 and T. Toda1
1Graduate School of
Engineering, Soka University, Hachioji, Tokyo 192-8577, Japan
2Center for
Regional Environmental Research, National Institute of Environmental Studies,
Tsukuba, Ibaraki 305-0053, Japan
3School of
Environment and Society, Tokyo Institute of Technology, Meguro, Tokyo
152-8550, Japan
4Laboratory of
Marine Biotechnology, Institute of Bioscience, Universiti Putra Malaysia,
43400 Serdang, Selangor Darul Ehsan, Malaysia
*Corresponding
Author E-mail: masa-kishi@soka.gr.jp
|
|
Key
words
Algal-bacterial consortium
Bacterial mineralization
Chlorella fusca
Ethylene glycol
Monoculture
Publication Data
Paper received : 09.06.2017
Revised received : 19.09.2017
Re-revised received :
25.11.2017
Accepted : 28.12.2017
|
Abstract
Aim: In this study,
ethylene glycol was supplied to an algal-bacterial consortium to investigate
the effect of bacterial mineralization of ethylene glycol on algal growth. ?
Methodology: Batch cultures of
bacteria and Chlorella fusca monocultures, as well as algal-bacterial
consortium were fed with 14,000 mg l-1 of ethylene glycol and
incubated in one liter glass bottles at 25?C with light intensity of 300 ?mol
m-2 s-1 in a 12 hr-light:12 hr-dark cycle. A
monoculture of C. fusca without ethylene glycol was also cultured
under similar conditions to test algal growth inhibition.?
Results: In the
consortium, there was more than 2-fold increase in the maximum algal specific
growth rate and a 1.3-fold increase in the maximum bacterial specific growth
rate. Furthermore, the maximum ethylene glycol removal efficiency by
consortium was 89%, while those by bacteria monoculture was 31%.? No apparent
removal of ethylene glycol by the C. fusca monoculture was observed.
Interpretation: The enhancement
of microbial growth rates and ethylene glycol degradation in consortium
compared to monocultures indicates that symbiotic relationship between algae
and bacteria enhanced oxygen and CO2 exchange between them, as a
result promoting growth and ethylene glycol degradation.? This study
demonstrated the possibility of an algal-bacterial system for the production
of microalgal biomass by feeding organic wastes, such as ethylene
glycol-containing wastewater.
|
|
Copyright
? 2018 Triveni Enterprises. All rights reserved. No part of the Journal can
be reproduced in any form without prior permission. Responsibility
regarding the authenticity of the data, and the acceptability of the
conclusions enforced or derived, rest completely with the author(s).
|