Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Jun 29;12(1):10945.
doi: 10.1038/s41598-022-15193-8.

Bioflocculant produced by Bacillus velezensis and its potential application in brewery wastewater treatment

Mayowa Agunbiade  1 , Babatunde Oladipo  2 , Adedeji Nelson Ademakinwa  3 , Oluyemi Awolusi  4 , Ibukun Modupe Adesiyan  5 , Oluwaseun Oyekola  2 , Olusola Ololade  6 , Abidemi Ojo  7
Affiliations

Bioflocculant produced by Bacillus velezensis and its potential application in brewery wastewater treatment

Mayowa Agunbiade et al. Sci Rep. .

Abstract

This study was designed to evaluate the potential of bioflocculant producing strains isolated from wastewater sludge. According to the Plackett-Burman design, the response surface revealed glucose, magnesium sulfate, and ammonium sulfate as critical media components of the nutritional source, whereas the central composite design affirmed an optimum concentration of the critical nutritional source as 16.0 g/l (glucose), 3.5 g/l magnesium sulfate heptahydrate (MgSO4.7H2O), and 1.6 g/l ammonium sulfate ( (NH4)2SO4), yielding an optimal flocculation activity of 96.8%. Fourier Transformer Infrared Spectroscopy (FTIR) analysis confirmed the presence of hydroxyl, carboxyl and methoxyl in the structure of the bioflocculant. Additionally, chemical analysis affirmed the presence of mainly a polysaccharide in the main backbone of the purified bioflocculant with no detection of protein. Energy Dispersive X-ray analysis affirmed the presence of chlorine, phosphorous, oxygen and chlorine as representatives of elemental composition. Thermogravimetric (TGA) analysis revealed over 60% weight was retained at a temperature range of 700 °C. The purified bioflocculant remarkably removed chemical oxygen demand, biological oxygen demand and turbidity in brewery wastewater. This study suggested that the bioflocculant might be an alternate candidate for wastewater treatment.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
Model adequacy plots of bioflocculation activity (a) predicted response vs experimental response; (b) normal plot of residuals; (c) residuals vs predicted, and (d) outlier t plot.
Figure 2
Figure 2
Surface plots of the influence of pertinent variables on the bioflocculation activity.
Figure 3
Figure 3
TGA/DTA analysis of purified bioflocculant.
Figure 4
Figure 4
FTIR spectrum of purified bioflocculant.
Figure 5
Figure 5
(a) SEM image and (b) EDX analysis of purified bioflocculant.
Figure 6
Figure 6
The effect of concentration on the treatment of brewery wastewater. The percentage of flocculating activities of different alphabetic letters differs significantly (p < 0.05).
See this image and copyright information in PMC

References

    1. Buthelezi S, Olaniran A, Pillay B. Turbidity and microbial load removal from river water using bioflocculants from indigenous bacteria isolated from wastewater in South Africa. Afr. J. Biotechnol. 2009;8:40.
    1. Prasertsan P, Dermlim W, Doelle H, Kennedy J. Screening, characterization and flocculating property of carbohydrate polymer from newly isolated Enterobacter cloacae WD7. Carbohydr. Polym. 2006;66:289–297. doi: 10.1016/j.carbpol.2006.03.011. - DOI
    1. Rudén C. Acrylamide and cancer risk—Expert risk assessments and the public debate. Food Chem. Toxicol. 2004;42:335–349. doi: 10.1016/j.fct.2003.10.017. - DOI - PubMed
    1. Agunbiade MO, Pohl CH, Ashafa AO. A review of the application of biofloccualnts in wastewater treatment. Pol. J. Environ. Stud. 2016;25:1–9. doi: 10.15244/pjoes/61063. - DOI
    1. You Y, et al. Use of waste fermenting liquor to produce bioflocculants with isolated strains. Int. J. Hydrogen Energy. 2008;33:3295–3301. doi: 10.1016/j.ijhydene.2008.03.049. - DOI

Supplementary concepts