Optimization and product characteristics of cyanobacteria-based plant growth stimulants by acid and thermal hydrolysis
This study utilized cyanobacteria as a raw material,subjecting it to acid-thermal hydrolysis.The optimal hydrolysis conditions for cyanobacteria were analyzed,and the safety of applying cyanobacteria-based plant stimulants to soil was evaluated using Pij、Igeo、RI and human exposure health risk assessment.Results demonstrated that using 2％oxalic acid for hydrolysis,exploiting the chelation effect of oxalic acid on heavy metals,and further adjusting the pH to 0.8 with sulfuric acid while maintaining a 24-hour hydrolysis constituted the optimal acid-thermal hydrolysis conditions to minimize environmental risks associated with cyanobacteria-based plant stimulants.The Pij、Igeo、RI of cyanobacteria-based plant stimulants prepared under various conditions indicated negligible risks,absence of pollution,and low-risk levels,respectively.Moreover,the calculated human carcinogenic and non-carcinogenic risks associated with plant stimulants were found to be below the safety thresholds of 10-6 and 1.In addition,using a semi-continuous acid-thermal hydrolysis system to enhance the concentration of beneficial substances in cyanobacteria-based plant growth stimulants,it was observed that after 3～4cycles of hydrolysis enrichment,the levels of nutrients(N,P,and K)in the plant growth stimulants stabilized at 3942,290.45,and 421.7mg/kg,respectively.Furthermore,2-(5H)-furanone and pyrrole compounds,classified as bio-stimulants,continued to accumulate in the plant growth stimulants,reaching levels of 29.5646 and 11.261mg/kg,respectively.These substances can effectively promote plant growth and inhibit pathogens.Moreover,alkaloids and phenolic compounds,considered as allelopathic substances,were degraded during hydrolysis,and subsequently alleviating the inhibitory effects on plant growth.
万方数据
维普
