TY - JOUR
T1 - Co-cultivation, metal stress and molasses
T2 - strategies to improving exopolymeric yield and metal removal efficacy
AU - Cheah, Caleb
AU - Cheow, Yuen Lin
AU - Ting, Adeline Su Yien
N1 - Funding Information:
The authors are grateful to the Malaysian Ministry of Education (MOE) for the funding under the FRGS grant scheme (FRGS/1/2018/STG03/MUSM/02/1). The authors also thank Monash University Malaysia for providing the resources and facilities to conduct the project.
Funding Information:
The authors are grateful to the Malaysian Ministry of Education (MOE) for the funding under the FRGS grant scheme (FRGS/1/2018/STG03/MUSM/02/1). The authors also thank Monash University Malaysia for providing the resources and facilities to conduct the project.
Publisher Copyright:
© 2022, The Author(s).
PY - 2022/1
Y1 - 2022/1
N2 - This study investigated and compared several improvement strategies to increase the yield and quality of exopolymeric substances (EPS) from Bacillus cereus. This includes co-culturing of B. cereus with Trichoderma asperellum, cultivation in media with metal (Zn) stress and supplementation with molasses. EPS is subsequently extracted from these different cultures and subjected to characterization and metal removal tests in single-metal systems (Cu, Pb, Zn, Cd, Cr). Results indicate that co-cultivation of B. cereus and T. asperellum produced EPS which have attributes differing from single cultivation. These changes were detected via functional group changes using Fourier-Transform Infrared Spectroscopy, as well as the increase in carbohydrate and protein content. However, the interaction of these two microbes were merely additive and did not result in improved EPS yield nor the subsequent metal removal efficacy in comparison to single cultivation (control). By contrast, supplementation of Zn (metal stress with 50 mg L− 1 Zn) improved EPS quality and metal removal, but decreased EPS yield. The application of 1% molasses was the only strategy demonstrating high yield and efficient metal removal. EPS quality and yield (0.45 mg mL− 1) and metal removal efficacy (Cu: 58%, Pb: 98%, Zn: 83%, Cd: 73%, Cr: 96%) were improved significantly. This study showed that among the three improvement strategies (co-cultivation, metal stress, molasses), supplementation with molasses was the most effective as it improved both yield and quality of EPS significantly, suggesting that this approach may be adopted for future production of bulk EPS for up-scaling of wastewater treatment.
AB - This study investigated and compared several improvement strategies to increase the yield and quality of exopolymeric substances (EPS) from Bacillus cereus. This includes co-culturing of B. cereus with Trichoderma asperellum, cultivation in media with metal (Zn) stress and supplementation with molasses. EPS is subsequently extracted from these different cultures and subjected to characterization and metal removal tests in single-metal systems (Cu, Pb, Zn, Cd, Cr). Results indicate that co-cultivation of B. cereus and T. asperellum produced EPS which have attributes differing from single cultivation. These changes were detected via functional group changes using Fourier-Transform Infrared Spectroscopy, as well as the increase in carbohydrate and protein content. However, the interaction of these two microbes were merely additive and did not result in improved EPS yield nor the subsequent metal removal efficacy in comparison to single cultivation (control). By contrast, supplementation of Zn (metal stress with 50 mg L− 1 Zn) improved EPS quality and metal removal, but decreased EPS yield. The application of 1% molasses was the only strategy demonstrating high yield and efficient metal removal. EPS quality and yield (0.45 mg mL− 1) and metal removal efficacy (Cu: 58%, Pb: 98%, Zn: 83%, Cd: 73%, Cr: 96%) were improved significantly. This study showed that among the three improvement strategies (co-cultivation, metal stress, molasses), supplementation with molasses was the most effective as it improved both yield and quality of EPS significantly, suggesting that this approach may be adopted for future production of bulk EPS for up-scaling of wastewater treatment.
KW - Biosorption
KW - Co-cultivation
KW - Exopolymeric substances
KW - Metal stress
KW - Molasses
KW - Wastewater treatment
UR - http://www.scopus.com/inward/record.url?scp=85123413478&partnerID=8YFLogxK
U2 - 10.1186/s42834-022-00121-2
DO - 10.1186/s42834-022-00121-2
M3 - Article
AN - SCOPUS:85123413478
VL - 32
JO - Sustainable Environment Research
JF - Sustainable Environment Research
SN - 2468-2039
IS - 1
M1 - 9
ER -