黄酮化合物对球形棕囊藻(Phaeocystis globosa)生长和光合活性的影响

EFFECTS OF FLAVONOIDS ON GROWTH AND PHOTOSYNTHETIC ACTIVITY OF PHAEOCYSTIS GLOBOSA

近年来,我国近岸海域赤潮暴发日益频繁,严重危害海洋生态环境、渔业及近海旅游业等海洋经济的发展,也给人类健康带来了威胁。本文研究了两种黄酮化合物槲皮素和杨梅素对我国赤潮暴发种球形棕囊藻生长的影响,并利用调制叶绿素荧光技术探究藻细胞光合作用PSⅡ反应中心光合活性对黄酮胁迫的响应。结果表明:槲皮素和杨梅素均能有效抑制球形棕囊藻的生长(半抑制浓度IC50,5d值分别为0.068和0.309mg/L);槲皮素(16.0mg/L)在第5天对藻细胞的抑制率达到最大(89.38%±0.42%),杨梅素(16.0mg/L)在第7天对藻细胞的抑制率达到最大(84.76%±1.82%);相较于杨梅素胁迫,球形棕囊藻的光合作用对槲皮素胁迫更敏感[0.20mg/L槲皮素胁迫7天后,最大光化学量子产量(Fv/Fm)、实际光化学量子产量(Yield)、最大相对电子传递速率(rETRmax)和光能利用效率(α)值分别降低18%、14%、24%和28%]。研究结果以期为赤潮暴发的防治技术提供基础的理论科学参考。

Red tides occur frequently in Chinese coastal waters,which seriously endangers the marine ecological environment and development of fisheries and offshore tourism,as well as brings a threat to human health.The effects of quercetin and myricetin on the growth of Phaeocystis globosa,a typical red tide organism in China were studied.And the response of algal photosynthetic activity(PSII reaction center)to the stress of flavonoid was also investigated by the state-of-the-art modulated chlorophyll fluorescence technique.Both quercetin and myricetin effectively inhibit the growth of Phaeocystis globosa(The IC50,5d values were 0.068 and 0.309mg/L,respectively);the inhibition rate of quercetin(16.0mg/L)on algae cells reached the highest(89.38%±0.42%)on the 5th day,while myricetin(16.0mg/L)on algae cells reached the highest(84.76%±1.82%)on the 7th day.Compared to myricetin,the photosynthesis of Phaeocystis globosa was more sensitive to quercetin.After 7 days treatment of 0.20mg/L quercetin,the maximum photochemistry quantum yield(Fv/Fm),actual photochemistry quantum yield(Yield),maximum relative electron transfer rate(rETRmax)and utilization efficiency of light energy(α)values of the algal cells were reduced by 18%,14%,24%and 28%,respectively.