The purpose of this work is to study the co-cultivation of Chlorella sp. and wastewater wild algae under different cultivation conditions （i.e. CO2, light intensity, cultivation time, and inoculation ratio） for enha...The purpose of this work is to study the co-cultivation of Chlorella sp. and wastewater wild algae under different cultivation conditions （i.e. CO2, light intensity, cultivation time, and inoculation ratio） for enhanced algal biomass and lipid productivity in wastewater medium using Response SuHhce Methodology （RSM）. The results show that mixed cultures ofd7llorella sp. and wastewater wild algae increase biomass and lipid yield. Additionally, findings indicate that CO2, light intensity and cultivation time significantly affect algal productivity. Furthcnnore, CO2 concentration and light intensity, and CO2 concentration and algal composition, have an interactive effect on biomass productivity. Under dii＂ferent cultivation conditions, the response of algal biomass, cell count, and lipid productlvlty ranges from2,5 to 10.2 mg/mL 1.1 × 10 to 8.2 × 10 cells/mL and 1.1 × 10^6 to 6.8 × 10^12 total fluorescent units/mL, respectively× The optimum conditions tbr simt, ltaneot, s biomass and lipid accumulation are 3.6% of CO2 （v/v）, 160 μmol/m^2/s of light intensity, 1×6/2.4 of inoculation ratio （wastewater-algae/Chlorella）, and 8.3 days of cultivation time. The optimal productivity is 9,8 （g/L） for dry biomass, 8.6 E ＋ 08 （cells/mL） for cell count, and 6.8 E ＋ 12 （Total FL units per mL） fbr lipid yield, achieving up to four times, eight times, and seven times higher productivity compared to non- optimized conditions. Provided is a supportive methodology to improve mixed algal culture for hioenergy feedstock generation and to optimize cultivation conditions in complex wastewater environments. This work is an important step tbrward in the development of sustainable large-scale algae cultivation for cost-efficient generation of biofuel.展开更多
By finding some important culture conditions as below, we succeeded in experimentally controlling the whole life history of a dioecious marine green alga, Bryopsis plumosa （Hudson） C. Agardh. In this study, we focus...By finding some important culture conditions as below, we succeeded in experimentally controlling the whole life history of a dioecious marine green alga, Bryopsis plumosa （Hudson） C. Agardh. In this study, we focused on the primary and secondary sex ratios （i.e. at inception and maturity） using these culture techniques. Gametogenesis was induced by culturing haploid gametophytes with Provasoli＇s enriched seawater （PES） medium under a 14：10 h light： dark cycle at 14 ℃. Formed zygotes grew into diploid sporophytes, which were cultured for 3 months with PES medium under a 14：10 h light ： nbsp;dark cycle at 18℃. Then they were transferred into Schreiber medium and cultured under a 10：14 h light： dark cycle at 22℃. Within 1 week, zoosporogenesis was observed. Zoospores were released within a couple of days. Each zoospore soon germinated and grew into a unisexual gametophyte. The primary sex ratio was examined in gametophytes that originated from a single sporophyte. The secondary sex ratio was studied in the field. Both were estimated as 1：1. Synchronized meiotic cell divisions might occur during zoosporogenesis dividing each sex-determining factor evenly among zoospores. Given the equal sex ratio at maturity, there seems to be no environmental factor that differentially affects the survival of male or female gametophytes in nature.展开更多
文摘The purpose of this work is to study the co-cultivation of Chlorella sp. and wastewater wild algae under different cultivation conditions （i.e. CO2, light intensity, cultivation time, and inoculation ratio） for enhanced algal biomass and lipid productivity in wastewater medium using Response SuHhce Methodology （RSM）. The results show that mixed cultures ofd7llorella sp. and wastewater wild algae increase biomass and lipid yield. Additionally, findings indicate that CO2, light intensity and cultivation time significantly affect algal productivity. Furthcnnore, CO2 concentration and light intensity, and CO2 concentration and algal composition, have an interactive effect on biomass productivity. Under dii＂ferent cultivation conditions, the response of algal biomass, cell count, and lipid productlvlty ranges from2,5 to 10.2 mg/mL 1.1 × 10 to 8.2 × 10 cells/mL and 1.1 × 10^6 to 6.8 × 10^12 total fluorescent units/mL, respectively× The optimum conditions tbr simt, ltaneot, s biomass and lipid accumulation are 3.6% of CO2 （v/v）, 160 μmol/m^2/s of light intensity, 1×6/2.4 of inoculation ratio （wastewater-algae/Chlorella）, and 8.3 days of cultivation time. The optimal productivity is 9,8 （g/L） for dry biomass, 8.6 E ＋ 08 （cells/mL） for cell count, and 6.8 E ＋ 12 （Total FL units per mL） fbr lipid yield, achieving up to four times, eight times, and seven times higher productivity compared to non- optimized conditions. Provided is a supportive methodology to improve mixed algal culture for hioenergy feedstock generation and to optimize cultivation conditions in complex wastewater environments. This work is an important step tbrward in the development of sustainable large-scale algae cultivation for cost-efficient generation of biofuel.
基金a grant-in-aid from the Ministry of Education, Culture and Science of Japan.
文摘By finding some important culture conditions as below, we succeeded in experimentally controlling the whole life history of a dioecious marine green alga, Bryopsis plumosa （Hudson） C. Agardh. In this study, we focused on the primary and secondary sex ratios （i.e. at inception and maturity） using these culture techniques. Gametogenesis was induced by culturing haploid gametophytes with Provasoli＇s enriched seawater （PES） medium under a 14：10 h light： dark cycle at 14 ℃. Formed zygotes grew into diploid sporophytes, which were cultured for 3 months with PES medium under a 14：10 h light ： nbsp;dark cycle at 18℃. Then they were transferred into Schreiber medium and cultured under a 10：14 h light： dark cycle at 22℃. Within 1 week, zoosporogenesis was observed. Zoospores were released within a couple of days. Each zoospore soon germinated and grew into a unisexual gametophyte. The primary sex ratio was examined in gametophytes that originated from a single sporophyte. The secondary sex ratio was studied in the field. Both were estimated as 1：1. Synchronized meiotic cell divisions might occur during zoosporogenesis dividing each sex-determining factor evenly among zoospores. Given the equal sex ratio at maturity, there seems to be no environmental factor that differentially affects the survival of male or female gametophytes in nature.
