The extensive outbreak of Sargassum horneri in China has not merely imposed a severe threat to the ecological environment and human life in coastal waters but also impeded the development of waterway transportation and the local economy. Consequently, we isolated polysaccharides from S. horneri, designated as SHP, and evaluated the antioxidant activity of SHP both in vitro and in vivo by investigating the effect of SHP on H2O2-induced African green monkey kidney cells (Vero cells) and zebrafish. The results demonstrated that SHP can enhance the activities of superoxide dismutase, catalase, and glutathione peroxidase in zebrafish. It also effectively inhibits micro malondialdehyde and ROS levels in Vero cells and zebrafish to mitigate the oxidative damage caused by H2O2, thereby achieving the protective effect of SHP on Vero cells and zebrafish. In conclusion, SHP holds the potential as a natural antioxidant. SHP can be contemplated for utilization as a natural antioxidant in the biomedical, cosmetic, and food industries, thereby alleviating the environmental stress caused by S. horneri and achieving resource utilization.

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为探究铜藻多糖（Sargassum horneri polysaccharides， SHP）对H 2 O 2 诱导的人角质形成细胞（HaCaT）氧化应激损伤的保护作用，测定了SHP对总抗氧化能力（T-AOC）、DPPH自由基、羟自由基（·OH）和超氧阴离子自由基（■）的清除作用，以评价SHP的体外抗氧化能力，并建立H 2 O 2 诱导HaCaT细胞氧化损伤模型；通过测定细胞存活率、细胞活性氧以及酶活，评价SHP对HaCaT细胞氧化损伤的保护作用。结果表明，当SHP体积浓度为1 mg/mL时，DPPH的清除率为68%、·OH清除能力65.48 U/mL；在SHP体积浓度为3 mg/mL时，■清除能力为84.86 U/mL，T-AOC为33.55。SHP能显著提高H 2 O 2 诱导氧化损伤的HaCaT细胞活力，其中经体积浓度为100 μg/mL SHP处理后，HaCaT细胞存活率由56.85%提高到80.57%，并且显著降低细胞内ROS水平，提高细胞内SOD活力，减少细胞内MDA的含量（P＜0.05）。因此，SHP对H 2 O 2 诱导的HaCaT细胞氧化应激损伤具有保护作用，SHP可作为一种天然的抗氧化剂在化妆品以及药妆品领域具有广阔的应用前景。

To develop a more comprehensive understanding of the efficacy of trans-vp28 gene Synechocystis sp. PCC6803 and its effect on white spot syndrome virus (WSSV), this study investigated the activities of several immune-related enzymes including acid phosphatase (ACP), alkaline phosphatase (AKP) and peroxidase (POD) in muscle and hepatopancreas of Penaeus vannamei, and conducted a more intuitive analysis from the perspective of histopathology. P. vannamei were orally fed trans-vp28 gene Synechocystis sp. PCC6803 for 10 days and then challenged with WSSV. The cumulative survival rate, activities of enzymes and the histopathology were determined. The results show that on the 7th day after challenge, the survival rate of the experimental group (i.e., challenged and fed mutant Synechocystis sp. cells) and the wild type group (i.e., challenged and fed wild type Synechocystis sp. cells) were 80.2% and 26.4%, respectively, while all shrimp in the positive control group (i.e., challenged, but no vaccination) died. There was no death in the negative control group (i.e., no vaccination or challenge). After immunization, the activities of ACP, AKP and POD in both tissues were the highest in the experimental group. After challenge, the final enzyme activities of the three enzymes in the experimental group were higher than those in the positive control group and the wild type group. The results of histopathology showed that muscle fibers in the negative control group were neatly arranged with numerous and evenly distributed nuclei, while muscle fibers in the positive control group and the wild type group were wavy. The nuclei of muscle fibers in the positive control group were also swollen and unevenly distributed. The nuclei of the muscle fibers in the experimental group were slightly clustered, and the muscle fibers were arranged neatly. In hepatopancreas samples, narrow cell gaps and regular nuclei were observed in the negative control group. The connective tissue and cell walls were severely damaged and the cells were degraded in the positive control group. However, although the connective tissue of the experimental group was slightly loose, the cells were orderly and the nuclei were arranged neatly. These results indicated that trans-vp28 gene Synechocystis sp. PCC6803 could improve the immunity of shrimp.

随着化妆品行业的迅猛发展以及人们对美的追求,天然温和、绿色安全的环境友好型化妆品已经成为广大消费者的诉求.消费者更青睐于以天然产物为基础的化妆品,而不是合成化学品.随着天然产物化学和海洋生物资源技术的迅速发展,藻类(包括大型藻和微藻)生物活性物质已得到了广泛的应用.许多研究已经证明藻类活性物质具有保湿补水、抗氧化、抗衰老、美白抗皱、抗菌消炎和日 光防护等功效.因此,从藻类中提取的生物活性物质在化妆品行业中具有潜在的应用价值.为此,本文将从藻类活性物质的生物学功能以及藻类在化妆品中的应用和绿色生物提取技术进行综述,以期为藻类生物活性物质在化妆品行业的研究开发提供参考.

White spot syndrome virus (WWSV) has become one of the most widespread causes of mortality in commercial shrimp farming. In the present study, we used PCR to determine the shrimp infectious dose 50% endpoint (SID 50 ml -1 ) of a Chinese isolate of WSSV in 5 different sizes of pathogen-free Litopenaeus vannamei inoculated intramuscularly. The lethal dose 50% endpoint (LD 50 ml -1 ) was also determined from the percentage of dead shrimp. The LD 50 ml -1 for 2, 4, 6, 8, and 10 cm shrimp were 10 4.68 , 10 5.7 , 10 6.70 , 10 7.75 , and 10 8.81 , respectively, and the SID 50 ml -1 were 10 4.68 , 10 5.70 , 10 6.90 , 10 7.75 , and 10 8.94 , respectively. There was no significant difference between the LD 50 ml -1 and SID 50 ml -1 for each shrimp size, which indicated that all infected shrimp died. The lethal and infectious titer decreased about 1 log 10 as shrimp size decreased 1 grade. These data clearly indicate that adult shrimp were more susceptible to WSSV than juvenile shrimp. The horizontal comparison showed that the amount of virus in the shrimp organs increased over the experimental period. The vertical comparison showed that virus quantity was lowest in the organs of 10 cm shrimp and highest in 2 cm shrimp, which indicates that the smaller shrimp had higher levels of viral replication. Hence, the optimal size for WSSV challenge in shrimp inoculated intramuscularly was 2 cm. The determination of virus titers in different sizes of shrimp represents a step towards creating strategies to reduce the negative impacts of WSSV in the aquaculture industry.