The extraction of pigments from fresh <Emphasis Type="Italic">Laminaria japonica</Emphasis>

The pigments in Laminariajaponica was extracted with six organic solvents and analyzed in spectroscopy analysis. The extractions conditions were screened by an orthogonal test and the quantity of extracted pigments was determined spectroscopically. The results show that： （1） among the six organic solvents, acetone was the most effective one for the extraction; （2） the optimum extraction conditions were as follows： the ratio of S/M （solvent volume/ material weight） was 30 ml/g; fresh seaweed was extracted 2 times in 2 h; （3） the average total content of pigments was 1.85 mg/g （calculated with dry L. japonica）.     

Gaussian decomposition and component pigment spectral analysis of phytoplankton absorption spectra

The absorption spectrum of phytoplankton is an important bio-optical parameter for ocean color hyperspectral remote sensing;its magnitude and shape can be aff ected considerably by pigment composition and concentration. We conducted Gaussian decomposition to the absorption spectra of phytoplankton pigment and studied the spectral components of the phytoplankton, in which the package effect was investigated using pigment concentration data and phytoplankton absorption spectra. The decomposition results were compared with the corresponding concentrations of the five main pigment groups (chlorophylls a , b , and c , photo-synthetic carotenoids (PSC), and photo-protective carotenoids (PPC)). The results indicate that the majority of residual errors in the Gaussian decomposition are <0.001 m^-1 , and R 2 of the power regression between characteristic bands and HPLC pigment concentrations (except for chlorophyll b) was 0.65 or greater for surface water samples at autumn cruise. In addition, we determined a strong predictive capability for chlorophylls a , c , PPC, and PSC. We also tested the estimation of pigment concentrations from the empirical specific absorption coeffi cient of pigment composition. The empirical decomposition showed that the Ficek model was the closest to the original spectra with the smallest residual errors.The pigment decomposition results and HPLC measurements of pigment concentration are in a high consistency as the scatter plots are distributed largely near the 1:1 line in spite of prominent seasonal variations. The Wozniak model showed a better fit than the Ficek model for Ch1 a , and the median relative error was small. The pigment component information estimated from the phytoplankton absorption spectra can help better remote sensing of hyperspectral ocean color that related to the changes in phytoplankton communities and varieties.     

Depth influence on biochemical performance and thallus size of the red alga Gelidium corneum

Recent declines in the foundation species Gelidium corneum (Hudson) J.V. Lamouroux in pristine coastal stretches of the Southeastern Bay of Biscay have been documented in which individuals showed a high bleaching incidence. Among the potential factorsthat may be responsible for these changes in G. corneum abundance, it has been suggested that high levels of irradiance may be imposing stressful environmental conditions for shallow populations. Given that light is reduced exponentially as depth increases, in this investigation we examined the influence of depth on the stress of G. corneum by comparing the performance of several biochemical parameters and thallus size in plants collected at three different depths. The results revealed that plants growing in shallow waters showed lower antioxidant activity, lower concentrations of photosynthetic pigments (Chl‐a, total carotenoids, phycoerythrin), lower internal nitrogen levels (higher C:N ratio) and shorter thallus lengths than those living in deeper waters. Some of these results may be an expression of photoacclimation, but the low antioxidant activity and total carotenoid concentration detected in plants living in shallow waters suggest that the photoprotective mechanisms of G. corneum may have failed to offset photodamage. If so, our findings support previous studies that suggest that recent changes in solar radiation are partially responsible for G. corneum declines. Nevertheless, given that the metabolic performance of macroalgae is determined by the inter‐play of irradiance with other factors, including temperature and nutrient availability, further research is needed to reach a better understanding of the factors causing stress in G. corneum.     

高通量测序技术揭示印度尼西亚北苏拉威西岛一株色素异常澄黄滨珊瑚特异的共生微生物群落

细菌性疾病对珊瑚的健康影响造成了很大影响,而致病菌与珊瑚疾病之间的对应性还不明朗。色素异常现象是野外澄黄滨珊瑚一种常见的不健康状态。我们采用Illumina 16s rRNA基因高通量测序技术比较分析了健康和色素异常澄黄滨珊瑚共生细菌的群落组成差异。色素异常澄黄滨珊瑚共生细菌的多样性明显高于健康澄黄滨珊瑚,同时两种珊瑚的共生细菌群落组成也有很大差异。一些特定的细菌类群在澄黄滨珊瑚共生细菌中的比例很高,推测这些细菌种类可能是导致澄黄滨珊瑚色素异常的“罪魁祸首”。     

富营养化湖泊水体中藻蓝蛋白提取方法的对比

藻蓝蛋白是蓝藻的指示型色素,目前还没有标准的提取方法,特别是萃取剂的选择品种较多,对测量结果影响较大.分别以室内培养的铜绿微囊藻和巢湖夏季野生蓝藻为提取对象,运用液氮反复冻融法破碎蓝藻细胞,分别以Asolctin-CHAPS缓冲液(AC)、磷酸盐缓冲液(PBS)和Tris-HCl缓冲液来提取藻蓝蛋白,通过分光光度法分析提取液的吸收光谱、藻蓝蛋白浓度以及藻蓝蛋白浓度与叶绿素a浓度的相关性,比较3种缓冲液的提取效果.结果显示:3种缓冲液提取的藻蓝蛋白提取液在620 nm处都出现了藻蓝蛋白的特征吸收峰,但AC缓冲液和PBS缓冲液提取效率明显高于Tris-HCl缓冲液.另外,虽然AC缓冲液提取效率最高,但其成本昂贵、配制过程复杂且不易控制、难保存,不适宜大规模地推广应用;而PBS缓冲液的提取效率略低于AC缓冲液,但其配制方便快捷,更适合于大规模湖泊水质监测的要求,因此推荐PBS缓冲液作为常用的藻蓝蛋白提取液.     

南极普里兹湾临近海域夏季纽鳃樽对浮游植物的摄食研究

于 1 998年 1 2月至 1 999年 1月南极夏季 ,对南大洋普里兹湾临近海域主要被囊类纽鳃樽的数量密度分布进行了现场调查 ,同时于 - 3站对纽鳃樽对浮游植物的摄食率利用肠道色索法和颗粒递减法进行了现场研究。调查结果表明 ,纽鳃樽主要分布于调查海区的浮冰区北部边缘及其以北的开阔水域。在密集区其数量密度高达 2 795ind..1 0 0 0 m- 3,浮冰区几乎没有发现。 - 3站现场摄食实验结果显示 ,纽鳃樽个体肠道色素含量变化范围为 0 .1 4～ 1 .2 7μg.ind.- 1,平均为0 .98μg.ind.- 1。肠道色素法测得的纽鳃樽对浮游植物的摄食率为 7.9μg.ind.- 1d- 1,滤水率为2 81 ind.- 1d- 1。颗粒递减法测得纽鳃樽滤水率为 1 5.3± 4.61 ind.- 1d- 1,比肠道色素法所得结果偏低。虽然由此推算纽鳃樽群体的日摄食量只占浮游植物现存量的 0 .8% ,但是对于初级生产力却有一定的摄食压力 ( 72 .2 % )。     

硅藻与色素在古环境演化研究中的意义——以固城湖为例

根据固圾湖ＧＳ１孔沉积物中硅藻的丰度与组合、色素的含量与有关参数,并结合孢粉、有机碳等分析数据,较详细地讨论了从晚冰期到全新世中期（１５．３￣６．０ｋａＢ．Ｐ．）固城湖地区古气候古环境演化的过程。同时尝试把硅藻与色素的结合作为度量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。文中还专门论述了全新世纪初期海相硅藻出现的层位特点与背景,并与太湖作了比较,这一现象对重新认识长江三角洲地     

RSM方法用于产红色素发酵培养基优化

用RSM方法对黄杆菌属产红色素菌株S-9801(Flavobacterium sp.)的培养基进行了优化.首先用部分重复因子实验对培养基组分蛋白胨、酵母粉、葡萄糖及NaCl浓度对菌株产红色素的影响进行评价,找出主要影响因子为葡萄糖和NaCl浓度.两者均为正影响,其他组分对色素含量的影响不显著.第二步用最陡爬坡路径逼近最大响应区域.最后用中心组合设计及响应面分析确定主要影响因子的最佳浓度.菌株在优化培养基中培养较初始培养基色素含量提高320%.     

糖蜜酒精废液中色素提取工艺的研究

研究了用膜分离技术从糖蜜酒精废液中提取焦糖色素的方法，实验证明，运用该方法色素总回收率为78.18%。通过对提取的色素性质的详细研究，认为回收色素已达到GB8871-2001标准要求，可供开发和利用。     

Recovery of astaxanthin from discharged wastewater during the production of chitin

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.