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131.
Xiaolin Chen Shengfeng Yang Ronge Xing Huahua Yu Song Liu Pengcheng Li 《中国海洋大学学报(英文版)》2012,11(2):249-252
In this paper, studies were carried out to extract astaxanthin from discharged wastewater during the production of chitin and to reveal the scavenging effect of the obtained pigment on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. Different ratios of dichloromethane/methanol (V/V) were used to extract astaxanthin. When the ratio of dichloromethane/methanol was 2:8 and the ratio between the mixed organic solvent (dichloromethane/methanol, 2:8, V/V) and wastewater was 1:1, the highest yield of pigment was obtained (8.4 mg/ 50 mL). The concentration of free astaxanthin in the obtained pigment analyzed by HPLC was 30.02%. The obtained pigment possessed strong scavenging ability on DPPH radical and IC50 was 0.84mg/ml. 相似文献
132.
Spatial variability of summer and autumn phytoplankton community structure in Xiamen Western Bay based on pigment analysis 总被引:2,自引:0,他引:2
The spatial variations of phytoplankton community structure in the Xiamen Western Bay during the summer and autumn cruises in 2001 were investigated based on HPLC analysis of photosynthetic pigments in algal cells and CHEMTAX processing of pigment data.The Chl a concentration reached 18.9 μg/L in the summer and declined to 0.28-2.17 in the autumn,respectively,consistent with the observation of diatom blooms in June.Among the accessory pigments,fucoxanthin was consistently the most abundant,ranging from 0.172 to 8.46 μg/L,with the maximum concentrations in June.19'-hexfucoxanthin and alloxanthin were the other two abundant pigments in the summer and autumn.In addition,19'-butanoyloxyfucoxanthin or peridinin was also important in late autumn.Generally the biomass of all the phytoplankton or each group was higher in the inner part than the mouth of this bay,represented by Chl a.CHEMTAX processing revealed the dominance of diatoms with their contribution of 14.6%-52.5% to the total Chl a,but its importance decreased in the autumn.Cryptophytes and Haptophytes,with an average contribution of 16.9%-31.4% and 12.1%-26.3%,were the other two important groups,especially in the autumn.On the contrary,Dinoflagellates and Chlorophytes were the minor groups,but the former became important sporadically in the autumn.It was suggested that there was distinctive variation in both the phytoplankton community structure and biomass between summer and autumn in the Xiamen Western Bay and the latter was coupled to the changes in temperature and dissolved oxygen.However,the spatial variation of the phytoplankton community structure was not as clear as the trend in the biomass of phytoplankton among all the sites in this bay. 相似文献
133.
近2600年来内蒙古居延海湖泊沉积物的色素含量及环境意义 总被引:10,自引:0,他引:10
通过分析东居延海S1探坑剖面色素含量,结合碳酸盐、介形类化石、腐殖酸、磁化率及化学元素等多环境指标分析结果,探讨该区近 2 6 0 0年来环境气候波动特点。研究区气候变化大致经历几个阶段:温暖湿润(2 6 5 0~ 2 5 6 0aB.P.)→湖泊菱缩,气候偏干暖 (2 5 6 0~ 2 36 0aB.P.)→暖湿气候背景下湖泊的扩张 (2 36 0~2 1 2 0aB.P.)→冷湿向冷干转换,湖泊由大湖开始菱缩 (2 1 2 0~ 1 6 0 0aB.P.)→气候暖湿,湖泊再次扩张,(1 6 0 0~ 6 5 0aB.P.)→湖泊由扩张到菱缩,气候由冷湿向暖干变化 (6 5 0aB.P.-至今 )。同时尝试把色素与其它指标的结合作为指示湖泊古初始生产力的有效性,以及识别沉积记录有关人类活动的可能性。 相似文献
134.
An 82 cm core was collected from Qinghai Lake in the Qinghai-Xizang Plateau, China and sectioned in intervals of 1 cm for
analysis of pigments (i. e. chlorophyll derivatives, carotenoids, myxoxanthophyll, oscillaxanthin) and210Pb.210Pb dating was used to establish the chronological sequence. The concentrations of myxoxanthophyll and oscillaxanthin from
the cyanophytes increase with temperature. There are four peak values at 0–14 cm (present−1891a), 25 cm (1786a), 45 cm (1581a),
60 cm (1416a) representing four warm and low water level periods during the past 700 years. This was confirmed by the high
concentration of carbonate and ∂13C in these stages. In these 700 years, there were also 4 periods of cold wet climate and high water level as indicated by
the tree ring index and high value of native chlorophyll and high, variable CD/TC ratios.
The project was supported by the Loess and Quaternary Research Lab, Academia Sinica. 相似文献
135.