Physiological Characteristics of Nitzschia hantzschia in Response to Nitrobenzene Stress

This study was conducted to investigate the effects of different mass concentrations of nitrobeneze on the growth, soluble sugar content, soluble protein content, chlorophyll a content and algal cell conductivity of Nitzschia hantzschia. The results showed that as the concentration of nitrobenzene increased, the growth of N. hantzschia was inhibited, and the algal culture liquids gradually changed from dark yellow to light yellow after 5 d of treatment;the soluble sugar content increased after 2 d;and the soluble protein content of the 100 mg/L nitrobenzene treatment group was 89.1% of the control group on day 1, which was the lowest value, and then showed a gradual upward trend. The low-mass concentration of nitrobenzene promoted the chlorophyll a content of algal cells, the medium and high mass concentrations had an inhibitory effect, and the chlorophyll a content of the 50 mg/L treatment gradually recovered after 3 d. The electrical conductivity of algal cells gradually increased with the increase of the mass concentration of nitrobenzene. The electrical conductivity gradually recovered after 3 d of the low mass concentration treatment, while the high mass concentration harmed the algae cells, causing N. hantzschia to gradually die.