Although one of the major users of flocculants are water and wastewater treatment industries, flocculants are also used in various food industries. The chemical flocculants are preferred widely in these industries due to low production cost and fast production ability. However, the negative effects of the chemical flocculants should not be neglected to gain the economic benefits only. Therefore, the researchers are working to discover efficient and economical flocculants from biological sources. Several attempts have been made and are still being made to extract or produce bioflocculants from natural sources such as plants, bacteria, fungi, yeast, algae, etc. The review revealed that significant amount of work have been done in the past, in search of bioflocculant. However, commercially viable bioflocculants are yet to be marketed widely. With the advent of new biotechnologies and advances in genetic engineering, the researchers are hopeful to discover or develop commercially viable, safe and environmentfriendly bioflocculants.
Optimization of the process conditions of mixed culture of bacidiomycete fungi for improved protein enrichment of fruit peels is necessary to ease replication and scale-up processes. Sixday fermentation period and temperature of 32°C were optimum for elevated protein synthesis and enzyme activities (78.99 units/ml for α-amylase and 0.36 units/ml for cellulase). A highly significant quadratic model obtained from Face Centered Central Composite Design (FCCCD) described the process optimization. Linear effect of pH and inoculum size were significant (p < 0.05) while pH and moisture content (MC) interact significantly. 70.2% MC, pH 5.4 and 6.1% inoculum were the optimum level for a maximum crude protein synthesis of 198.77 mg/g. The crude protein contained essential and non-essential amino acid at a comparable level with other bioprocessed materials that are currently used as animal feed supplement.
Media components such as wheat flour, MgSO4 and particle size were screened by Placket Burman design (PBD) while the operating range was fixed by one-factor-at-a-time method (OFAT), primarily for the enrichment of cassava peels as animal feed. Optimization of the selected media components was carried out using Face–Centered Central Composite Design (FCCCD) of the Response Surface Methodology (RSM) and the responses were measured in term of protein and lignin contents. Statistical analysis of the result showed that the quadratic term of wheat flour and the interaction between wheat flour and particle size were highly significant (P