Utilization of Water Hyacinth (Eichhornia crassipes) as a Feasible Substrate for the Production of Single Cell Protein Using Saccharomyces cerevisiae (Baker's Yeast)

Purpose The main purpose of the research work relies on the bioconversion of water hyacinth (aquatic weed) leaves into a useful substrate for the production of single cell protein using Saccharomyces cerevisiae under fermentation process, which not only eliminate environmental degradation but also enhance the utilization rate of resource. The investigation further extends the possibility of manipulating antioxidant efficacy and aminoacid profiling of produced single cell protein whereby it can be used as a food or feed for its high protein content. Methods The nutritive parameters of water hyacinth were examined to determine their suitability as a low cost carbon substrate for SCP synthesis. By using the one-factor-at-time (OFAT) technique, the optimization of bioprocess variables was carried out to maximize SCP yield. To achieve the highest possible amount of biomass with high protein content, SCP was mass produced using a liquid state fermentation technique. The DPPH and total antioxidant assay was analyzed to determine the obtained SCP's antioxidant activity. Through the HPTLC aminoacid profiling technique, the essential amino acids present in the yeast biomass were evaluated. Results Maximum SCP yield (17.25 g/l) and protein content (38.43%) was achieved with optimized water hyacinth hydrolysate based medium when compared with unoptimized medium with SCP yield (12.48 g/l) and protein content (26.10%). Further, nucleic acid reduction treatment was undergone which apparently reduced the dry biomass (14.96 g/l) and protein content (36.27%) in SCP. The produced SCP also exhibited promising antioxidant potential with 42.34 mu g/ml total antioxidant and 95.26 mu g/ml scavenging activity. The HPTLC profile of SCP showed a considerable concentration of the important essential amino acids arginine (0.65 mg/g), valine (3.51 mg/g), threonine (2.59 mg/g), and tryptophan (3.69 mg/g). Conclusion Thus, the current study concluded that employing invasive aquatic weed (water hyacinth) as a cost-effective feedstock for the fermentation based production of SCP with increased biomass yield and protein content seems to be a promising circular bioeconomy approach.