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61.
The present study was conducted to evaluate the effects of astaxanthin (AST) against lipopolysaccharide (LPS)‐induced lymphocyte viability, ultrastructural lesions, apoptosis, oxidative stress and inflammatory responses in Channa argus. Lymphocytes exposed to more than 10 μg/ml LPS alone for 24 hr showed significantly decreased cell viability, elevated nitric oxide (NO) and malondialdehyde (MDA), lactate dehydrogenase (LDH) contents, and increased nuclear factor κB p65 (NF‐κB p65), myeloid differential protein‐88 (MyD88), tumour necrosis factor‐α (TNF‐α), interleukin‐1β (IL‐1β), interleukin‐8 (IL‐8), caspase‐3, caspase‐8 and caspase‐9 gene expression. LPS at a concentration of 10 μg/ml could induce oxidative stress and inflammatory responses in lymphocytes. The activities of antioxidant enzymes (catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD)) were significantly decreased after exposure to 10 μg/ml LPS. Besides, AST strikingly antagonized the LPS‐induced negative effects. AST significantly increased the expression of HSP70, HSP90, IκB‐α, and glucocorticoid receptor (GR) and decreased inflammatory responses. Further study showed that AST can activate GR signalling pathway and inhibit p65 phosphorylation. In addition, AST attenuated LPS‐induced apoptosis, mitochondrial swelling, degeneration and vacuolization. Collectively, these findings suggest that AST has protective roles in LPS‐induced cell damage via modulating GR activation in C. argus lymphocytes.  相似文献   
62.
以贵州草海自然水域捕获的新鲜小龙虾(Procambarus clarkii)为材料,采用单因素实验研究了提取溶液、料液比、提取温度、提取时间、提取次数对虾青素提取效果的影响,用分光光度法测定了草海小龙虾不同部位虾青素的含量。结果表明,以乙酸乙酯为提取溶液,料液比为1∶2(g∶mL),在60℃下提取2 h,重复提取两次,再此提取条件下虾壳中虾青素含量最高。在虾壳、虾肉和内脏三个部位中,虾壳中虾青素含量最高,虾肉和内脏中也含有少量虾青素,但是含量远低于虾壳中的含量,说明了小龙虾虾青素主要富集在虾壳中。  相似文献   
63.
Astaxanthin (AST) is a product made from marine organisms that has been used as an anti-cancer supplement. It reduces pontin expression and induces apoptosis in SKBR3, a breast cancer cell line. Using Western blotting and qRT-PCR analyses, this study revealed that in the T47D and BT20 breast cancer cell lines, AST inhibits expression of pontin and mutp53, as well as the Oct4 and Nanog cancer stem cell (CSC) stemness genes. In addition, we explored the mechanism by which AST eradicates breast cancer cells using pontin siRNAs. Pontin knockdown by pontin siRNA reduced proliferation, Oct4 and Nanog expression, colony and spheroid formation, and migration and invasion abilities in breast cancer cells. In addition, reductions in Oct4, Nanog, and mutp53 expression following rottlerin treatment confirmed the role of pontin in these cells. Therefore, pontin may play a central role in the regulation of CSC properties and in cell proliferation following AST treatment. Taken together, these findings demonstrate that AST can repress CSC stemness genes in breast cancer cells, which implies that AST therapy could be used to improve the efficacy of other anti-cancer therapies against breast cancer cells.  相似文献   
64.
Rainbow trout with an average initial weight of 160 g were fed during 42 days diets containing varied keto‐carotenoids astaxanthin (Ax)/canthaxanthin (Cx) ratio, as follows: Ax 100% : Cx 0%; Ax 75% : Cx 25%; Ax 50% : Cx 50%; Ax 25% : Cx 75% and Ax 0% : Cx 100%. Muscle colour and carotenoid muscle retention were studied. Colour parameter values for mixed astaxanthin–canthaxanthin‐fed fish were intermediate between those obtained for Ax 0% : Cx 100% fed fish group and for Ax 100% : Cx 0% fed fish group. Concerning muscle carotenoid retention, it has been observed that as the level of canthaxanthin in diet increased, the muscle total carotenoid retention decreased. In the mean time, as the level of canthaxanthin in diet increased, the muscle astaxanthin retention decreased while that of canthaxanthin increased. The results reported here provide further evidence of non‐beneficial effects in terms of muscle colour and muscle carotenoid retention of the use of varying dietary astaxanthin/canthaxanthin ratio for feeding rainbow trout compared to values obtained for astaxanthin‐only feed.  相似文献   
65.
To assess the effects of dietary astaxanthin on the growth and body colour of red discus fish (Symphysodon spp.), synthetic astaxanthin was added into the basal diet (beef heart hamburger) with the levels of 0 (control diet), 50, 100, 200, 300 and 400 mg kg?1 respectively. The six experimental diets were fed to discus fish with an initial body weight of 10.3 ± 0.8 g for 8 weeks. The results showed that the supplementation of 50–200 mg kg?1 astaxanthin had no significant effects on growth performance of discus fish, but the high supplementation of astaxanthin (300 or 400 mg kg?1) significantly reduced the weight gain and increased the feed coefficient ratio (< 0.05). After 4 or 8 weeks of feeding, the L* (lightness) values in astaxanthin‐supplemented groups were significantly lower, while a* (redness), b* (yellowness) and skin astaxanthin contents were significantly higher than the control group (< 0.05). When the astaxanthin supplementation reached 200 mg kg?1, skin redness and astaxanthin contents remained relatively stable. When b* was relatively stable, the supplemental astaxanthin was 300 (4 weeks) and 50 mg kg?1 (8 weeks) respectively. With the supplemental astaxanthin increasing, the astaxanthin retention rate significantly decreased and hepatic total antioxidant capacity was strengthened. The dietary astaxanthin also significantly increased the reduced glutathione level (< 0.05) when the astaxanthin inclusion was higher than 50 mg kg?1. The above results showed that dietary astaxanthin could effectively improve the skin pigmentation of red discus fish in 4 weeks and the supplementation level was suggested to be 200 mg kg?1.  相似文献   
66.
The aim of this work was to evaluate the effects of Haematococcus pluvialis (H. pluvialis) (carotenoid source) and H. pluvialis plus soy lecithin on development, carotenoid content, and pigmentation of shrimp (Litopenaeus vannamei). One hundred and eighty shrimps (7.8 g) were divided in six tanks (n = 30) and fed with control food, H. pluvialis, and H. pluvialis plus soy lecithin for 2 weeks. Carotenoids were extracted with acetone and quantified by UV–vis spectrophotometry, and astaxanthin was determined by high‐performance liquid chromatography. Colour was analysed by colorimetry. Lecithin/H. pluvialis group presented higher survival rate (100%) when compared to control group (93.3%). Haematococcus pluvialis and lecithin/H. pluvialis groups presented higher red‐like colour (a* 16.4 and 19.9) than control (a* 20.6). Lecithin/H. pluvialis group presented higher carotenoids content (8.2 mg kg?1 muscle, 26.8 mg kg?1 exoskeleton) and astaxanthin (8.5 mg kg?1 muscle, 23.3 mg kg?1 exoskeleton) than control (carotenoids: 4.2 mg kg?1 muscle, 12.3 mg kg?1 exoskeleton; astaxanthin: 3.2 mg kg?1 muscle, 8.1 mg kg?1 exoskeleton). Feeding with 60 ppm carotenoids (from H. pluvialis) during 2 weeks was sufficient for favouring red‐like pigmentation in shrimp, and lecithin increased astaxanthin content only in exoskeleton.  相似文献   
67.
在育肥饲料中添加虾青素会影响中华绒螫蟹肠道及鳃内的可培养优势菌群以及机体的免疫力,本实验旨在探讨饲料中虾青素含量及养殖水体对其肠道和鳃部菌群的影响。采用不同虾青素含量的饲料(0.00、26.60、41.62、81.37和75.35 mg/kg,分别对应饲料1#~5#)对雄性中华绒螫蟹进行育肥70 d后,利用基础培养基和选择性培养基对其肠道、鳃及养殖水体中的细菌进行传统分离和纯化,所得菌株进行16S rRNA测序,再进行同源性分析后做系统进化树。结果发现,在分离获得的106株细菌(登录号:KU570293~KU570368,KU570370,KU570372~KU570383,KU601302~KU6013 16,KU720553)中,92株为优势菌株,其中,肠道、鳃部和水体各29、32和31株。肠道中的可培养优势细菌属于柠檬酸杆菌属、假单胞菌属和气单胞菌属;而鳃中可培养优势细菌属于柠檬酸杆菌属、芽孢杆菌属、假单胞菌属和气单胞菌属;养殖水体中可培养优势细菌属于芽孢杆菌属、气单胞菌属、柠檬酸杆菌属、假单胞菌属和黄杆菌属。饲料2#组肠道中可培养细菌总数最高(1.06×10~8cfu/g);饲料5#肠道中的潜在致病菌数量最低,但其可培养细菌总数显著高于其他饲料组;饲料3#组肠道和鳃中潜在致病菌数量相对较高。研究表明,饲料中添加不同含量的虾青素能够显著影响雄性中华绒螫蟹肠道和鳃中的菌群构成,但对水体中可培养细菌数量无显著影响。本研究首次对投喂不同含量虾青素饲料的育肥期雄性中华绒螫蟹肠道、鳃及养殖水体可培养的优势细菌数量和组成进行分析,探究了饲料中虾青素含量以及养殖水体与蟹肠道内可培养细菌之间的联系,为中华绒螫蟹营养免疫和菌群调控提供了理论基础。  相似文献   
68.
正交试验优化天然虾青素的提取工艺研究   总被引:2,自引:1,他引:1  
徐竞 《南方水产》2008,4(2):69-74
研究了负压空化法提取虾壳中虾青素的各项工艺条件对虾青素提取效果的影响,通过正交试验确定了负压空化法提取最佳工艺参数为提取溶剂是浓度80%的乙醇溶液,提取时间为35min,料液比为1:20,通气量为0.2m^3·h^-1。同时将负压空化法与常用破壁提取方法的提取效果和效率进行了比较,综合结果表明,负压空化法优越于其它方法,是一种能够适应工业生产的新型提取方法。  相似文献   
69.
虾青素对日本沼虾血细胞密度及吞噬活力的影响   总被引:1,自引:0,他引:1  
从雨生红球藻粉中提取虾青素,以60mg/kg的浓度添加到日本沼虾(Macrobrachium nipponemis)的配合饵料中,在实验室条件下饲养三周,研究虾青素对日本沼虾血淋巴密度及吞噬活力(吞噬百分比和吞噬指教)的影响。结果显示添加虾青素组的日本沼虾不论是血细胞密度还是吞噬活力都显著高于对照组,表明虾膏素可显著提高日本沼虾的免疫力。  相似文献   
70.
The deposition of natural, optically active, astaxanthin fatty acid esters in rainbow trout ( Oncorhynchus mykiss ) was studied. Mono-esterified and di-esterified (3 S ,3' S ) astaxanthin were purified from the green microalga Haematococcus pluvialis and incorporated into extruded diets and compared with diets containing synthetic racemic astaxanthin (Carophyll Pink) and a total carotenoid extract from the alga. All sources of astaxanthin achieved >4 mg kg−1 in the white muscle after 6 weeks feeding. No significant difference ( P  > 0.05) between the deposition of astaxanthin or total carotenoid for the different diets was observed. Other xanthophylls, namely lutein, zeaxanthin and idoxanthin were found in the white muscle of rainbow trout fed all diets and together accounted for 10–14% of total carotenoid. Astaxanthin was deposited in the white muscle in the stereochemical form administered in the diet, i.e. racemic astaxanthin for Carophyll Pink and ˜100% (3 S ,3' S )-astaxanthin for the algal sources. In contrast, epimerization of (3 S ,3' S ) astaxanthin from the alga was observed for the astaxanthin esters deposited in the skin of rainbow trout, with a ratio close to 1.0:2.0:1.0 (3 S ,3' S :3 R ,3' S :3 R ,3' R ).  相似文献   
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