Cultivation Of Spirulina In Soy Sauce Wastewater And Analysis Of Its Nutritional Components

Soy sauce is a common condiment.With the pursuit of flavor diversification,the output of soy sauce increases year by year,and the resulting soy sauce wastewater also increases.As a kind of organic wastewater with high concentration and high chroma,the treatment method of soy sauce wastewater involves the combination of physical,chemical and biological processes,which makes the treatment cost higher.In order to make the soy sauce wastewater better utilized,this paper takes the Spirulina Sm-4 and soy sauce wastewater as the research object.The soy sauce wastewater is used to replace the traditional medium for the cultivation of Sm-4.By measuring the content of the nutrients of Sm-4,the effect of soy sauce wastewater on the growth and the change of its nutrient composition is studied.Meanwhile,the other high added value components of Sm-4 were determined and the potential of its subsequent utilization was analyzed.The main conclusions are as follows:The culture of Spirulina Sm-4 in soy sauce wastewater resource shows that:there are more carbon containing organic matter and nitrogen and phosphorus in soy sauce wastewater which can be absorbed and utilized by microalgae,and it can be considered that soy sauce wastewater is basically non poisonous,which indicates that soy sauce wastewater has potential for microalgae culture;Sm-4 showed good adaptability to the appropriate amount of soy sauce wastewater,and there was no growth stagnation period,but 25% of the replacement ratio was the most suitable.Under this condition,the growth rate of Sm-4 was obviously accelerated,and the highest biomass of each group was 2.71 g/l,and it was found that Sm-4 could not survive in 100% soy sauce wastewater.The analysis and Research on the basic nutrient components of Spirulina Sm-4from soy sauce wastewater showed that: soy sauce wastewater had a positive effect on the synthesis of Sm-4 pigment,which made the content of chlorophyll a and carotenoid increased significantly,and both of them were positively related to the proportion of soy sauce wastewater;When the replacement ratio of soy sauce wastewater was 25%,the content and purity of Sm-4 protein and phycocyanin were not significantly different from that of the control group,but the content of oil and polysaccharide was significantly different,but when the replacement ratio was 50%and 75%,the content of each substance was significantly different;The absorption and fluorescence spectra of Sm-4 pigment and phycocyanin showed that there was no significant difference between 25% Sm-4 and Zarrouk control group.However,when the ratio of soy sauce wastewater reached 50% and 75%,the light density value corresponding to the characteristic absorption peaks in the absorption spectrum decreased,and the fluorescence intensity in the fluorescence spectrum decreased.The analysis and Research on the high added value components of Spirulina Sm-4 from soy sauce wastewater resource showed tha:t when the replacement ratio of soy sauce wastewater was 25%,the synthesis of vitamin C in Sm-4 was inhibited,but the synthesis of vitamin E was promoted;At the same time,the content of malondialdehyde and catalase activity fluctuated slightly in Sm-4,but the activity of total superoxide dismutase was increased,and the total antioxidant capacity was improved slightly;The content of calcium,magnesium and zinc in Sm-4.was increased obviously by soy sauce wastewater,while the content of iron and potassium decreased slightly,while the content of sodium decreased obviously.