Study On The Properties Of Soluble Algal Products

The emerging of microalgae culture technology offers the possibility to produce biofuelby wholesale. However, the soluble algal products(SAP) have uncertain effect on algal growth,which may restrict the reuse of culture medium. Scenedesmus sp. LX1and Haematococcuspluvislis were chosen to study the growth characteristic and the production rate of solublealgal products measured by DOC. The influence of soluble algal products on alga growth wasalso tested. What’s more, we investigated the culture condition influences on the productionrate of soluble algal products.The results indicated that Haematococcus pluvialis had the similar specific growth rateas Scenedesmus sp. LX1. The properties of SAP have the obvious differences between species.Algae dencity became stable at the stationary phase, while SAP increased rapidly. We’d betterto harvest algal at this phase.SAP secreted by S.LX1could inhibit its growth through all the growth period, theinhibition effect increase with the increasing of SAP dencity. However, the inhibition effectof the secretions of Haematococcus pluvislis was not decreased with the decreasing of SAPdencity.The effect of environmental factors on the SAP production rate of S.LX1were studied.Temperature had little effect on growth, however high temperature decreased the productionrate of SAP. Illumination intensity had enhancing effect on growth and restraining theproduction rate of SAP. Alkali conditions had enhancing effect on growth, besides extremealkali and acid conditions enhancing the production rate of SAP. Inoculum density had littleeffect on both growth and the production rate of SAP. Initial concentration of TN/TP hadgreat effect on specific growth rate and the production rate of SAP. The specific growth rateand the production rate of SAP increased under high density of nutrient element. so does theabsorbing rate of TN/TP by Scenedesmus sp. LX1.