Temporal and Spatial Distribution of Ulva.prolifera in the Yellow Sea and Influence of Typhoon “CHAN-HOM” in 2015

A recurrent floating green algae bloom was detected in the Yellow Sea since 2007.The Ulva.prolifera is non\|toxic,but the massive accumulations can result in significant environmental damage and cause economic loss to marine industries.In this study,the spatial and temporal patterns of Ulva.prolifera green tides were investigated in the Yellow Sea during 2015 using HJ\|1A/1B and MODIS satellite images by means of NDVI (normalized difference vegetation index)and artificial interpretation.The results showed：(1)A little Ulva.prolifera was discovered firstly in adjacent sea of Yancheng,Jiangsu province in early May with distribution area 0.831 km².Under the action of the southeast monsoon,Ulva.prolifera was gradually drifted to Shandong peninsula waters from south to north.The influential area and range reached a peak value with 1 752.756 km² in late June,and gradually subsided from July to August.And Ulva.prolifera about 38.791 km² was monitored in the South Bay of North Korea.In conclusion,Ulva.prolifera in the Yellow Sea in 2015 has experienced five major processes including “Occur\|Development\|Outbreak\|Recession\|Disappeared”.(2)Typhoon "CHAN\|HOM" certainly influenced the northward pathway of Ulva.prolifera and shifted towards the southwest,resulting in most of Ulva.prolifera moved to the east coast of Lianyungang,and speculated that minority Ulva.prolifera drifted to the South Bay of North Korea.(3)From the monitoring data,the spatial resolution between MODIS and ENVISAT (HJ\|1A / 1B)is difference significantly,250 m and 30 m respectively.A functional relation of the two data with monitoring area difference about 2.26 times was established to make up for the shortage of the environmental satellite (HJ\|1A/1B)images.      

南海条浒苔和裂片石莼的油脂提取及其脂肪酸分析

以南海条浒苔和裂片石莼为原料,用索氏提取器进行油脂提取,通过脂肪酸室温甲酯化,应用GC-MS联用技术对提取的油脂成分进行了分析。最佳提取条件为:乙醚作溶剂、提取温度40℃、提取时间6h。得到条浒苔10种脂肪酸成分,其中7种为不饱和脂肪酸,占油脂总量的45.54%;裂片石莼10种脂肪酸中有6种不饱和脂肪酸,占油脂总量的49.89%。     

酶法提取高品质浒苔膳食纤维工艺

以浒苔为原料,对浒苔膳食纤维提取和漂白工艺条件进行探讨;通过正交试验设计确定酶法提取膳食纤维和漂白的最佳条件。酶法提取膳食纤维的最佳条件,蛋白酶处理的温度为25℃、pH5、用酶量1%、时间为60min;α-淀粉酶处理的温度为30℃、pH6、用酶量0.1%、时间为20min;最佳漂白条件,漂白液浓度0.80%、pH6、漂白时间10min。在此条件下,提取率为40.22%、膨胀力为45.13mL/g、持水力为2171%。产品可作为高品质膳食纤维及理想的食品添加剂。     

Antioxidant properties of extract and fractions from Enteromorpha prolifera, a type of green seaweed

The ethanol extract and its solvent subfractions, partitioned by n-hexane (HX), chloroform (CF) and ethylacetate (EA), from Enteromorpha prolifera were measured for antioxidant activities, and a structural identification of the active compound was performed using spectroscopic techniques. The CF fraction showed the most potent 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl (OH) radical scavenging activities with strong reducing ability. The DPPH and hydroxyl radical scavenging capacities of the CF fraction were comparable to the capacities of the positive controls, BHA and α-tocopherol, at concentrations ranging from 0.25 to 1.0 mg/mL. However, little correlation (r² = 0.03–0.48) was observed between antioxidant activities and total phenolic contents of the extracts. Further fractionation and spectroscopic analysis of the CF fraction suggested that the strong antioxidant activity of the extracts from E. prolifera was because of a chlorophyll compound, pheophorbide a, rather than phenolic compounds.     

Investigation of nickel(II) biosorption on Enteromorpha prolifera: optimization using response surface analysis

In this study, the biosorption of nickel(II) ions on Enteromorpha prolifera, a green algae, was investigated in a batch system. The single and combined effects of operating parameters such as initial pH, temperature, initial metal ion concentration and biosorbent concentration on the biosorption of nickel(II) ions on E. prolifera were analyzed using response surface methodology (RSM). The optimum biosorption conditions were determined as initial pH 4.3, temperature 27 degrees C, biosorbent concentration 1.2 g/L and initial nickel(II) ion concentration 100 mg/L. At optimum biosorption conditions, the biosorption capacity of E. prolifera for nickel(II) ions was found to be 36.8 mg/g after 120 min biosorption. The Langmuir and Freundlich isotherm models were applied to the equilibrium data and defined very well both isotherm models. The monolayer coverage capacity of E. prolifera for nickel(II) ions was found as 65.7 mg/g. In order to examine the rate limiting step of nickel(II) biosorption, such as the mass transfer and chemical reaction kinetics, the intraparticle diffusion model, external diffusion model and the pseudo second order kinetic model were tested with the experimental data. It was found that for both contributes to the actual biosorption process. The pseudo second order kinetic model described the nickel(II) biosorption process with a good fitting.     

常规荧光法与同步荧光法用于浒苔叶绿素a测定的比较研究

选用N,N-二甲基甲酰胺(DMF)作为浒苔叶绿素a的萃取剂,使用常规荧光法和同步荧光法对浒苔叶绿素a的测定进行了比较研究。结果显示,DMF作为萃取剂与传统的丙酮溶剂相比,具有提取时间短、效率高、操作简便等优点;常规荧光法和同步荧光法均可用于浒苔叶绿素a测定,测定结果无显著性差异;对青岛四个站点的20组浒苔样本叶绿素a进行比测分析的结果是,常规荧光法检测的浒苔叶绿素a含量分布为4.38～9.35mg/g;同步荧光法检测的浒苔叶绿素a含量分布为4.53～8.74mg/g。     

浒苔对营养性肥胖小鼠减肥功能的研究

目的:研究浒苔对营养性肥胖小鼠的减肥作用。方法:用营养饲料建立肥胖模型,造模成功小鼠分为模型组,浒苔高、中、低剂量组和阳性对照组。模型组小鼠喂以基础饲料并灌胃清水,浒苔高、中、低剂量组分别喂以添加质量分数30%、20%、10%浒苔的基础饲料并灌胃清水,阳性对照组喂以基础饲料并灌胃50mg/(100g.d)(以体质量计)的左旋肉碱。49d后眼球取血,测定小鼠体质量、Lee,s指数、脂肪系数及血清总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)含量和丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)活性。结果:高、中、低剂量浒苔及左旋肉碱均能有效降低雌性与雄性营养性肥胖小鼠体质量、Lee,s指数、脂肪系数及血清TC、TG、LDL-C含量和ALT、AST活性,升高HDL-C含量和HDL-C含量/T C含量。结论:浒苔具有良好的减肥功能,其机理可能是抑制脂肪生成、调节血脂、保护肝功能。     

缘管浒苔中粗多糖脱色方法的研究

青岛海域缘管浒苔提取的粗多糖中色素含量比较高,用活性炭、双氧水、ADS-7树脂进行脱色。通过单因素试验法确定了脱色的最佳方法,证明活性炭脱色效果最好。设计活性炭脱色正交试验,确定了活性炭的质量分数为6%,温度为35℃,脱色时间为40min时为最佳脱色工艺。     

浒苔多糖的结构、制备与降解研究进展

浒苔多糖作为浒苔的主要功能成分,具有多种生物活性,如免疫调节、抗氧化、抗肿瘤、降血脂等。但是由于其分子量较大,浒苔多糖具有溶解性差、生物利用率低等缺陷,这极大地限制了浒苔多糖资源的高值化开发和利用。浒苔多糖降解后得到的低分子量产物,在保持了多糖的多种生物活性的基础上,大大提升了其溶解性、生物利用度等,因而浒苔多糖降解产物的制备与活性研究已成为海洋生物资源开发研究领域的热点。目前,浒苔寡糖的制备主要是通过对浒苔多糖的降解实现的,主要方法包括化学降解法、物理降解法和酶降解法等。该研究综述了浒苔多糖的化学组成、结构、提取和纯化方法,并对浒苔多糖降解产物的制备方法和活性等进展进行了总结和展望,以期为浒苔多糖及其降解产物的研究提供理论基础,为推动海洋藻类多糖资源的高值化利用和开发提供参考。