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

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.

Isolation of a Marine Bacterium and Application of Its Bioflocculant in Wastewater Treatment

“…Therefore, the removal the efficiency of the bioflocculant implies its potential industrial applicability. The results were in agreement with those obtained by Agunbiade et al [60] and Pathak et al [61], whereby the bioflocculants were efficient in removing pollutants in wastewater.…”

Water Quality Improvement by Wild Bacilli Isolated from Marine Environments

“…Only 5.25 (PM-1) and 6.00 (BC06) mg/L were found in this study, which was less than the standard BOD of aquaculture effluent (≤20 mg/L). The result of Bacilli species was similar to the result of B. velezensis, which showed 46% of BOD removal [32]. While isolated cellulolytic Bacillus had reduced BOD by 90% [33], another B. subtilis was 93% of BOD removal [37].…”

“…It might be because they have co-metabolism to degrade or trap the particle suspension in the water sample. The result was according to the study of B. velezensis that showed TSS removal of brewery wastewater for 55% [32]. In an aquaculture pond, the solid suspension will be overshadowed by light through water which affects the primary production process of water.…”

“…Another study reported the COD removal efficiency of B. velezensis in a very high load of COD concentration (4,000 mg/L). Authors suggested that B. velezensis can remove COD volume by about 55% [32]. In addition, a COD reduction above 90% of another Bacillus was described by [33] and mentioned B. subtilis had an 80% COD decrease [37].…”

A bioflocculant from Corynebacterium glutamicum and its application in acid mine wastewater treatment

“…The analysis of variance (ANOVA) for the quadratic model was summarized in Table 2. Similarly to the study of Agunbiade et al (2022), the model F-value of 99.09 indicated that the model was highly statistically significant at p < 0.0001. The lack of fit F-value and p-value was found to be 4.4 and 0.093, indicating that the suitability of the model to predict the variations.…”