Evaluation of Macroalgae Sulfated Polysaccharides on the Leishmania (L.) amazonensis Promastigote

The sulfated polysaccharides from Solieria filiformis (Sf), Botryocladia occidentalis (Bo), Caulerpa racemosa (Cr) and Gracilaria caudata (Gc) were extracted and extensively purified. These compounds were then subjected to in vitro assays to evaluate the inhibition of these polysaccharides on the growth of Leishmania (L.) amazonensis promastigotes. Under the same assay conditions, only three of the four sulfated polysaccharides were active against L. amazonensis, and the polysaccharide purified from Cr was the most potent (EC₅₀ value: 34.5 μg/mL). The polysaccharides derived from Bo and Sf demonstrated moderate anti-leishmanial activity (EC₅₀ values of 63.7 μg/mL and 137.4 μg/mL). In addition, we also performed in vitro cytotoxic assays toward peritoneal macrophages and J774 macrophages. For the in vitro cytotoxicity assay employing J774 cells, all of the sulfated polysaccharides decreased cell survival, with CC₅₀ values of 27.3 μg/mL, 49.3 μg/mL, 73.2 μg/mL, and 99.8 μg/mL for Bo, Cr, Gc, and Sf, respectively. However, none of the sulfated polysaccharides reduced the cell growth rate of the peritoneal macrophages. These results suggest that macroalgae contain compounds with various chemical properties that can control specific pathogens. According to our results, the assayed sulfated polysaccharides were able to modulate the growth rate and cell survival of Leishmania (L.) amazonensis promastigotes in in vitro assays, and these effects involved the interaction of the sulfated polysaccharides on the cell membrane of the parasites.     

食品通电加热中极板污染问题研究进展

在食品物料加工过程中,对比传统加热技术,通电加热技术有加热快速、高效、容易控制等诸多优点,但是在加热过程中,电极极板的污染制约着通电加热技术的发展。本文对通电加热极板污染的研究现状做了分析,并总结了加热过程中影响极板污染的各种因素,提出了目前存在的问题,并指出了该技术的研究方向。      

Linking the biology and ecology of key herbivorous unicornfish to fisheries management in the Pacific

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The Anti-Inflammatory Effect of Algae-Derived Lipid Extracts on Lipopolysaccharide (LPS)-Stimulated Human THP-1 Macrophages

Algae contain a number of anti-inflammatory bioactive compounds such as omega-3 polyunsaturated fatty acids (n-3 PUFA) and chlorophyll a, hence as dietary ingredients, their extracts may be effective in chronic inflammation-linked metabolic diseases such as cardiovascular disease. In this study, anti-inflammatory potential of lipid extracts from three red seaweeds (Porphyra dioica, Palmaria palmata and Chondrus crispus) and one microalga (Pavlova lutheri) were assessed in lipopolysaccharide (LPS)-stimulated human THP-1 macrophages. Extracts contained 34%–42% total fatty acids as n-3 PUFA and 5%–7% crude extract as pigments, including chlorophyll a, β-carotene and fucoxanthin. Pretreatment of the THP-1 cells with lipid extract from P. palmata inhibited production of the pro-inflammatory cytokines interleukin (IL)-6 (p < 0.05) and IL-8 (p < 0.05) while that of P. lutheri inhibited IL-6 (p < 0.01) production. Quantitative gene expression analysis of a panel of 92 genes linked to inflammatory signaling pathway revealed down-regulation of the expression of 14 pro-inflammatory genes (TLR1, TLR2, TLR4, TLR8, TRAF5, TRAF6, TNFSF18, IL6R, IL23, CCR1, CCR4, CCL17, STAT3, MAP3K1) by the lipid extracts. The lipid extracts effectively inhibited the LPS-induced pro-inflammatory signaling pathways mediated via toll-like receptors, chemokines and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling molecules. These results suggest that lipid extracts from P. lutheri, P. palmata, P. dioica and C. crispus can inhibit LPS-induced inflammatory pathways in human macrophages. Therefore, algal lipid extracts should be further explored as anti-inflammatory ingredients for chronic inflammation-linked metabolic diseases.     

人工鱼礁和大型海藻对许氏平鲉和大泷六线鱼幼鱼的诱集作用

为了探究大型海藻和人工鱼礁对鱼类的诱集作用,依据崂山湾人工鱼礁区游泳动物和大型海藻调查结果,以海黍子、孔石莼、带形蜈蚣藻、石花菜和小珊瑚藻5种优势藻类,许氏平鲉和大泷六线鱼2种优势鱼类以及人工鱼礁模型为研究对象,于室内实验水槽观察了许氏平鲉和大泷六线鱼幼鱼在海藻和模型礁中的行为反应和分布。结果显示,水槽中未投放模型礁和海藻时,实验鱼密集出现在水槽边缘区(A9),分布率分别为75.71%±7.79%和73.63%±4.41%。放入模型礁和海藻丛后,许氏平鲉和大泷六线鱼出现短暂的排斥反应,然后迅速聚集其中;2种鱼对带形蜈蚣藻的响应时间最短[(12.75~21.00)s],对模型礁的响应时间最长[(66.50~151.25)s];带形蜈蚣藻聚集许氏平鲉用时最短[(151.50±8.14)s],海黍子聚集大泷六线鱼用时最短[(56.00±2.53)s];大泷六线鱼对模型礁的聚集时间为(216.25±5.59)s,远低于许氏平鲉(1343.50±5.38)s;2种鱼在模型礁中的停留时间远长于海藻丛,且大泷六线鱼的停留时间(211.85±7.96)s长于许氏平鲉(199.75±16.82)s。海藻丛和模型礁对2种岩礁性幼鱼的诱集效果明显,实验区幼鱼的分布率由未投放模型礁和海藻前的0.91%~8.78%上升到4.21%~31.42%;高密度带形蜈蚣藻和海黍子的诱集效果最好,对许氏平鲉和大泷六线鱼的聚集率分别达到30.42%±1.14%和31.42%±1.74%,而低密度小珊瑚藻的诱集作用不明显。     

人工鱼礁材料添加物碳封存能力及其对褶牡蛎(Ostrea plicatula)固碳量的影响

本研究将农渔废弃物(花生秸秆和海湾扇贝壳)作为鱼礁材料添加物,利用礁体自身碳封存增加人工鱼礁碳汇潜能的可行性,并通过研究礁体附着生物的变化特征,探讨礁体材料添加物对人工鱼礁生态系统生物固碳的影响.结果显示,实验海区礁体附着生物的优势种为褶牡蛎(Ostrea plicatula Gmelin),添加了花生秸秆和海湾扇贝壳的人工鱼礁并未显著增加褶牡蛎的附着量(P＞0.05).通过对添加物礁体自身碳封存量的计算,海湾扇贝壳添加物单位实验礁的最小碳封存量为104.13kg,最大碳封存量为260.32kg;花生秸秆添加物单位实验礁的最小碳封存量为296.28kg,最大碳封存量为740.70 kg;实验礁体添加物的总碳封存量达2802.87 kg.以此估算,如将实验所在的66.67 hm2礁区已投放的圆管型混凝土礁材料加入添加物,以海湾扇贝壳替代率为10％计算,至少可完成52040.00 kg碳的封存,以花生秸秆替代率为25％计算,礁体自身的碳封存量可达370350.00kg.     

Distribution of benthic communities in the fjord‐like Bathurst Channel ecosystem,south‐western Tasmania,a globally anomalous estuarine protected area

• 1. Benthic assemblages in the fjord‐like Bathurst Channel estuarine system, south‐western Tasmania, vary over horizontal scales of 1–5 km and vertical scales of 1–10 m. Multivariate analysis indicated a total of eight major assemblages that characterize different sections and depths of the channel.
• 2. Because tannins in the low‐salinity surface water layer block light, foliose algae reach 5 m depth in the marine western region but do not penetrate below 1 m in the east. By contrast, sessile invertebrates are most abundant below 5 m depth in the west and below 2 m in the east. Deeper assemblages are unlikely to be continuous with assemblages in deeper waters off the Tasmanian coast as they are highly constrained by depth within particular sections of the estuary.
• 3. While the species composition of the Bathurst Channel biota is most similar to that found elsewhere in Tasmania, the structural character of the biota in terms of major taxonomic groups is more closely allied to that found in fjords of south‐western Chile and south‐western New Zealand. These three regions all possess wilderness settings, high rainfall that is channelled through estuaries as a low‐salinity surface layer, deep‐water emergence of fauna, rapid change in biotic communities over short horizontal and vertical distances, and high levels of local endemism. They also include some of the most threatened aquatic ecosystems on earth due to increasing human activity from a near pristine base, and the potentially catastrophic impacts of climate change. Copyright © 2009 John Wiley & Sons, Ltd.

     

黄斑篮子鱼(Siganus oramin)对北方养殖网箱网衣附着藻类的生物清除作用

高温季节网衣附着藻类的大量附着是北方网箱养殖产业面临的主要问题之一,生物清除策略是解决这一问题的有效手段.本研究利用黄斑篮子鱼(Siganus oramin)作为网衣附着藻类生物清除的工具种,于2015年6-11月,采用室内实验和现场观测相结合的方法,系统研究了桑沟湾楮岛海域网箱养殖区不同水层网衣附着藻类生物量的月际变化、黄斑篮子鱼对优势藻类的摄食能力及对网衣藻类的清除效果.结果显示,同一月份不同深度附着藻类生物量的日均增长量有一定差异,且不同水层在8月7日-9月14日时间段内的藻类附着日均增长量均显著高于其他月份(P＜0.01),各个月份海头红(Plocamium telfairiae)均为该区域的优势种类.构建了适温条件下黄斑篮子鱼对海头红的碳收支方程:100摄入碳=11.69生长碳+10.82粪便碳+6.06排泄碳+71.43代谢碳.初始体重为(1.44±0.61)g的黄斑篮子鱼经过152 d的养殖,平均体重达到(45.38±4.22)g,日均增重0.26 g.海区网箱内有无黄斑篮子鱼的对比实验显示,其对不同月份网衣附着藻类的清除率在80.28％-90.15％之间.研究表明,黄斑篮子鱼对网衣附着藻类有较高的清除效率,可以作为清除网衣附着生物的工具种.     

Exploring the Potential of Icelandic Seaweeds Extracts Produced by Aqueous Pulsed Electric Fields-Assisted Extraction for Cosmetic Applications

A growing concern for overall health is driving a global market of natural ingredients not only in the food industry but also in the cosmetic field. In this study, a screening on potential cosmetic applications of aqueous extracts from three Icelandic seaweeds produced by pulsed electric fields (PEF) was performed. Produced extracts by PEF from Ulva lactuca, Alaria esculenta and Palmaria palmata were compared with the traditional hot water extraction in terms of polyphenol, flavonoid and carbohydrate content. Moreover, antioxidant properties and enzymatic inhibitory activities were evaluated by using in vitro assays. PEF exhibited similar results to the traditional method, showing several advantages such as its non-thermal nature and shorter extraction time. Amongst the three Icelandic species, Alaria esculenta showed the highest content of phenolic (mean value 8869.7 µg GAE/g dw) and flavonoid (mean value 12,098.7 µg QE/g dw) compounds, also exhibiting the highest antioxidant capacities. Moreover, Alaria esculenta extracts exhibited excellent anti-enzymatic activities (76.9, 72.8, 93.0 and 100% for collagenase, elastase, tyrosinase and hyaluronidase, respectively) for their use in skin whitening and anti-aging products. Thus, our preliminary study suggests that Icelandic Alaria esculenta-based extracts produced by PEF could be used as potential ingredients for natural cosmetic and cosmeceutical formulations.     

附着生物对栉孔扇贝生长及存活的影响

对荣成市桑沟湾崖头养殖场扇贝养殖笼上附着生物的种类组成、消长规律、附着生物量的季节变化以及附着生物对扇贝生长存活的影响方面进行了调查研究。结果表明：扇贝养殖笼上附着生物的种类主要有海鞘(玻璃海鞘、柄海鞘、史氏菊海鞘、紫拟菊海鞘)、水螅(主要是鲍枝螅)、多管藻、海绵等;8月份附着生物总生物量达到最高峰,9月份开始逐渐下降;倒笼次数对栉孔扇贝的生长有较大影响：在实验养殖期中,每月倒笼1次组的体重增长最快,但死亡率最高;综合个体、体重增长以及死亡率来看。以每2个月倒换网笼1次、高温季节不倒笼为最佳。