The Use of Chitosan for Flocculation Recovery of Bacillus Biomass Grown on Dairy and Wine Industry Effluents (original) (raw)

Efficiency of chitosans applied for flocculation of different bacteria

Water research, 2002

Three types of well-characterized chitosans of different composition were applied to flocculate 8 different bacterial species. The aim of this study was to relate chitosan structure and flocculation characteristic to general bacterial characteristics such as the cell surface charge and hydrophobicity. Large differences in the flocculation efficiency of chitosan were found between different bacterial suspensions, both regarding the effective chitosan concentrations and the optimal type of chitosan. However, no correlation was observed between general surface characteristics of bacteria and flocculation by chitosan of different composition. It may be concluded that purely electrostatic interactions did not play a dominant role in flocculation of Gram-negative bacteria in this study. The presence of GlcNAc residues had clearly beneficial effects on flocculation in such cases.

Microbial reductions and physical characterization of chitosan flocs when using chitosan acetate as a cloth filter aid in water treatment

PLOS ONE, 2022

The World Health Organization (WHO) estimates 2.1 billion people lack access to safely managed water. Cloth filtration is often employed in rural and developing communities of South Asia for point-of-use water treatment, but bacteria and viruses are too small for efficient removal by this filtration method. Chitosan is a biodegradable, cationic, organic polymer derived from the chemical treatment of chitin that acts as a coagulant and flocculant of contaminant of microbes and other particles in water, thereby facilitating filtration of microbes. This research 1) evaluated the use of chitosan acetate as a pre-treatment coagulation-flocculation process followed by cloth filtration for microbial reductions and 2) assessed floc particle size under three stirring conditions. E. coli KO11 bacteria and MS2 coliphage virus removals were quantified using culture-based methods. Chitosan acetate coagulation-flocculation pre-treatment of water, followed by cloth filtration, met or exceeded the ...

Dairy and Wine Industry Effluents as Alternative Media for the Production of Bacillus-Based Biocontrol Agents

Bioengineering

Food industry effluents represent one of the major concerns when it comes to environmental impact; hence, their valorization through different chemical and biological routes has been suggested as a possible solution. The vast amount of organic and inorganic nutrients present in food industry effluents makes them suitable substrates for microbial growth. This study suggests two valorization routes for whey as dairy industry effluent and flotation wastewater from the wine industry through microbial conversion to biocontrol agents as value-added products. Cultivations of the biocontrol strain Bacillus sp. BioSol021 were performed in a 16 L bioreactor to monitor the bioprocess course and investigate bioprocess kinetics in terms of microbial growth, sugar substrate consumption and surfactin synthesis, as an antimicrobial lipopeptide. The produced biocontrol agents showed high levels of biocontrol activity against mycotoxigenic strains of Aspergillus flavus, followed by a significant redu...

Influence of Effluent Type on the Performance of Chitosan as a Coagulant

2014

The use of chitosan as a bio-polymeric coagulant has continued to attract interest in water treatment due to its biodegradability and non-toxicity. Its ability to treat effluents of high organic content has been investigated in some food processing industries. The focus of the present study is to compare results of the use of chitosan in the treatment of effluent from a Sugar Processing Plant (SPP), with those obtained from the treatment of wastewater from a Milk Processing Plant (MPP) and from a Brewery Processing Plant (BPP), in order to determine the influence of effluent type on the impurities removal efficiency. The treatment of the MPP provided the best removal efficiency (99% suspended solids removal and 70% COD removal) in comparison to the SPP (98% suspended solids removal and 11% COD removal) and BPP (95% suspended solids removal and 50% COD removal). The optimum pH value varied as a function of the type of effluent with BPP= 4.5, SPP = 4.5 and MPP =7. The results indicate...