Isolation, identification, and characterization of an Aspergillus niger bioflocculant-producing strain using potato starch wastewater as nutrilite and its application

Shengyan Pu; Hui Ma; Daili Deng; Shengyang Xue; Rongxin Zhu; Yan Zhou; Xingying Xiong

doi:10.1371/journal.pone.0190236

Isolation, identification, and characterization of an Aspergillus niger bioflocculant-producing strain using potato starch wastewater as nutrilite and its application

PLoS One. 2018 Jan 5;13(1):e0190236. doi: 10.1371/journal.pone.0190236. eCollection 2018.

Authors

Shengyan Pu^{1

2}, Hui Ma^{1

3}, Daili Deng¹, Shengyang Xue¹, Rongxin Zhu¹, Yan Zhou¹, Xingying Xiong¹

Affiliations

¹ State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Chengdu University of Technology), Chengdu, Sichuan, P.R. China.
² Department of Civil and Environment Engineering, The Hong Kong Polytechnic University, Hong Kong, P.R. China.
³ Department of Civil and Environment Engineering, Louisiana State University, Baton Rouge, Louisiana, United States of America.

Abstract

A bioflocculant (MBFA18) was produced by Aspergillus niger (A18) using potato starch wastewater (PSW) as nutrients. The cultivation processes and flocculating treatment for PSW purification were systematically studied. The flocculating rate of the MBFA 18 achieved 90.06% (kaolin clay) under the optimal cultivation condition (PSW with 5950 mg/L COD, 20 g/L glucose, 0.2 g/L urea and without phosphorus source addition and pH adjustment). Furthermore, effects of flocculant dosage, initial pH, coagulant aid (CaCl2) addition and sedimentation time on the PSW treatment were discussed and studied in detail. The optimum flocculation treatment conditions were determined according to the treatment efficiency, cost and flocculation conditions. During the PSW treatment, 2 mL/L bioflocculant (1.89 g/L) dosage and 0.5 mol/L coagulant aid addition were applied without pH adjustment and 91.15% COD and 60.22% turbidity removal rate could be achieved within 20 min. The comparative study between the bioflocculant and conventional chemical flocculants showed excellent flocculating efficiency of MBFA 18 with lower cost (4.7 yuan/t), which indicated that the bioflocculant MBFA 18 produced in PSW substrate has a great potential to be an alternative flocculant in PSW treatment.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aspergillus niger / isolation & purification*
Aspergillus niger / metabolism
Flocculation
Solanum tuberosum / metabolism*
Starch / metabolism*
Wastewater*

Substances

Waste Water
Starch

Grants and funding

This work was supported by the National Natural Science Foundation of China (41772264, 51408074 to SYP) and the Research Fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (SKLGP2017Z009 to SYP). Dr. S.Y. Pu is grateful for support from the Hong Kong Scholars Program (No. XJ2015005 and G-YZ80) and the Project Funded by China Postdoctoral Science Foundation (2015T80966). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.