Abstract:A pond-based experiment was conducted from 26 April to 12 December 2012,in order to evaluate the effects of polyculture of freshwater mussel Hyriopsis cumingii in the ponds of silver carp Hypophthalmichthys molitrix and bighead carp Aristichthys nobilis,on water quality,plankton community and mussel growth performance.During the experiment period,four mussel densities were set up:fish monoculture pond(0/m³),low density mussel polyculture pond(0.8/m³),medium density mussel polyculture pond(1.0/m³)and high-density mussel polyculture pond(1.2/m³).The results revealed that water quality parameters(TP,PO₄-P,NH₃-N,NO₂-N and NO₃-N)of the ponds with mussels were significantly lower than the fish monoculture ponds.All water quality parameters of medium density mussel polyculture ponds were significantly lower than those of the other three ponds,except that its chemical oxygen demand(COD)and NH₃-N showed no significant difference with that of low density mussel polyculture ponds.The plankton densities in fish monoculture ponds were significantly higher than those of mussel polyculture pond.In mussel polyculture ponds,negative correlation was found between phytoplankton density and mussel culture density.Phytoplankton biomass of fish monoculture pond was significantly lower than that of mussel polyculture pond,while significantly lower than that of the low density museel polyculture pond.Phytoplankton biomass positively correlated with mussel density.The biomass of green algae and bare algae significantly increased in the polyculture mussel pond.the mussel survival rates were significantly higher in low density and medium density mussel polyculture ponds than that of high-density polyculture pond,but the values of mussel wet weight,shell length and shell width were the highest in the low density mussel polyculture pond.This study indicated that polyculture with freshwater mussel can effectively improve the water quality,control excess growth of harmful algae,accelerate the growth of chlorella and euglenophyta,increase the biomass of plankton,and improve survival and growth performance of the mussels.Finally,this study demonstrated that the optimal culture density of freshwater mussel in the ponds of silver and bighead carps was 1.0/m³.

Abstract:An enclosure experiment was conducted to evaluate the effect of co-culturing freshwater pearl mussel Hyriopsis cumingii in a fish polycultural system consisting of grass carp Ctenopharyngodon idellus,gibel carp Carassius auratus,silver carp Hypophthalmichthys molitrix and bighead carp Aristichthys nobilis on fish yield and water quality.Two treatments were examined.In treatment Ⅰ,polyculture of grass carp,gibel carp,silver carp and bighead carp was used.In treatment Ⅱ,the mussel was co-cultured in polycultural system of grass carp,gibel carp,silver carp and bighead carp used in treatment Ⅰ with a mussel-fish ratio of 1：1.The experiment lasted 78 days,during which water samples were collected regularly,and species composition and biomass of phytoplankton,primary productivity(P),community respiration(R),dissolved oxygen(DO),pH,sechii depth(SD),main ions(CO₃^2-,HCO₃^-,Cl^-,SO₄^2-,Ca²⁺,Mg²⁺,Na⁺+K⁺),total alkalinity,total hardness,ammonia(TAN),nitrite,nitrate,reactive phosphate,total nitrogen(TN),total phosphorus(TP),total organic carbon(TOC),chemical oxygen demand(COD_Mn),biological oxygen demand(BOD₅)were monitored.The results showed that co-culturing H.cumingii significantly decreased the Ca²⁺ concentration in the enclosures,but did not significantly affect the other water quality parameters,such as species composition and biomass of phytoplankton,diversity of phytoplankton(Shannon-Weaver's index,Margalef's index,Pielou's index),P,R,DO,pH,SD,CO₃^2-,HCO₃^-,Cl^-,SO₄^2-,Ca²⁺,Mg²⁺,Na⁺+K⁺,total alkalinity,total hardness,TAN,nitrite,nitrate,reactive phosphate,TN,TP,TOC,COD_Mn and BOD₅.Yields of grass carp,gibel carp and silver carp were relatively high,while production of bighead carp and accumulation of TN,TP,COD_Mn,BOD₅ and TOC were low in treatment Ⅱ,compared with treatment Ⅰ.Therefore,co-culturing the mussel in a fish polycultural system of grass carp,gibel carp,silver carp and bighead carp not only enhanced economic income of aquaculture practice,but also reduced the accumulation of nitrogen,phosphorus and organic matter.

Abstract:The composition and diversity of bacterial community in Megalobrama amblycephala intensive rearing pond sediments were investigated by PCR-DGGE(denaturing gradient gel electrophoresis)and DNA sequencing technology.Sediments were collected at different depths(0-10 cm,10-20 cm,20-30 cm,30-40 cm)during non-feeding period.The structure feature displayed high levels in the richness of microbial communities(38)and Shannon-Wiener index(3.18).This represented that the Megalobrama amblycephala intensive rearing pond had a high microbial variety.The Shannon-Weiner index of the microbial community in the pelagic(0-10 cm,10-20 cm)(3.29,3.27)was slightly higher than that of the sub-bottom(20-30 cm)(3.17),and the index of the bottom(30-40 cm)was minimum(2.96),indicating the stability of the bacterial community structure.The microbial community structure showed a high degree of similarity(80%)at the pelagic(0-10 cm,10-20 cm)in different months,while the similarity between pelagic and bottom(20-30 cm,30-40 cm)was lower.Therefore,we could evaluate the sample space order through the similarity of the community structure.The diversity of microbial composition showed that the microflora in M.amblycephala intensive rearing period belonged to eight bacterial phyla:Proteobacteria 33.33%(β-,γ-,δ-Proteobacteria),Chloroflexi 19.05%,Bacteroidetes 14.29%,Cyanobacteria 9.52%,Acidobacteria 4.76%,Firmicutes 4.76%,Spirochaetes 9.52%,Nitrospirae 4.76%.The 16S rDNA clone library analysis indicated that there were lots of bacteria in the M.amblycephala intensive rearing pond sediments.The Proteobacteria which consisted mainly of δ-Proteobacteria was the dominant group in sediments.The results provided important information for selection of the beneficial bacteria and regulation of the micro-ecological environment in the M.amblycephala intensive rearing pond.

Abstract:This study was designed to determine the effects of dietary inositol on immune function of juvenile Wuchang bream(Megalobrama amblycephala)under ammonia stress.In trial,four hundred and fifty juvenile Wuchang bream with initial body weight of(3.40±0.07)g were randomly allocated to 6 groups(with 3 replicates)fed with purified diet containing inositol 0,101.2,202.3,404.8,809.1 and 1 616.4 mg/kg for 90 days.The results showed that,before ammonia stress,compared to the control group,Lym,C3,C4 and respiratory burst activity of fish fed diet 404.8 mg/kg inositol were significantly higher(P<0.05).Under ammonia stress for 12 hours,the WBC,RBC,Lym,HGB,C3 and C4 were significantly higher in the groups supplemented with 404.8 and 809.1 mg/kg inositol(P<0.05);respiratory burst activity was significantly higher than that of control(P<0.05);cortisol level was significantly decreased(P<0.05).Under ammonia stress for 72 hours,the WBC,RBC,Lym,HGB,C3 and respiratory burst activity fed diet 404.8 mg/kg inositol were significantly higher(P<0.05);cortisol level was significantly decreased(P<0.05);C4 levels was was significantly enhanced in the group supplemented with 809.1 mg/kg inositol(P<0.05).So,it is suggested that ingestion of a basal diet supplemented with inositol(404.8 mg/kg)can enhance immune function and resistance against ammonia stress of juvenile Wuchang bream.

Abstract:Indoor experiments were conducted to investigate the effect of constant light intensity on physiology and ecology characteristics of swimming crab(Portunus trituberculatus).The oxygen consumption rate(OCR),ammonia excretion rate(AER),O：N ratio,lactic acid(LD),energetic contents in hemolymph and respiratory enzyme activities including hexokinase(HK),pyruvate kinase(PK),succinate dehydrogenase(SDH)and lactate dehydrogenase(LDH)were tested in five constant light intensity treatments(0,200,800,1 500,3 500 lx).The main results were as follows:1.Light intensity influenced the OCR and AER significantly(P<0.05).The oxygen consumption rate of the crab under 200-1 500 lx was significantly higher than those of the crab under 0 lx and 3 500 lx(P<0.05).The ammonia excretion rate of the crab under 1 500 lx was significantly lower than others(P<0.05).2.Light intensity influenced total protein,but did not influence other energetic contents and O：N ratio significantly(P>0.05).Our results suggest that protein is used preferentially as energy source.3.Marked differences were found in LD(P<0.05).The LD in muscle of the crab under 1 500 lx was lowest.4.Different light intensity influenced different respiratory enzymes differently.Under 1 500 lx,the activity of HK and PK were at a high level.Glycolysis went faster and produced more energy.The activity of SDH was at a high level,while LDH was low.Aerobic metabolism was at a higher level,providing more energy for a continuous motion of crab The results revealed that light intensity affected respiratory metabolism,and the crab at 1 500 lx had higher metabolism while under less stress.So about 1 500 lx may be the better illumination condition of the crab culture industry.

Abstract:An 8-week feeding trial was conducted in a recirculated system to study the effect of dietary DHA to EPA ratios(0.64,0.97,1.18,1.59 and 1.91),with 0.74% n-3 HUFA and 8.3% lipid in dry feed,on growth performance,body composition and blood biological parameters in juvenile starry flounder,Platichthys stellatus.The results showed that:(1)fish weight gain rate(WGR),feed efficiency(FE),as well as protein efficiency ratio(PER)increased and then decreased with higher DHA/EPA values(P<0.05).Quadratic regression(y=-1.589 5x²+2.858 3x+45.184;R² =0.910 8,x=dietary DHA/EPA ratios,y=PRE)showed PRE decreases significantly beyond the DHA/EPA ratio of 0.90.Spleensomatic index(SSI)was enhanced by dietary DHA/EPA ratios and showed highest values of 0.12% in DHA/EPA ratio of 1.59,whereas hepatosomatic index(HSI)was decreased and then increased by dietary DHA/EPA ratios(P<0.05),with the lowest value being in DHA/EPA ratio of 1.18(2.85%).(2)Liver lipid was obviously decreased(from 13.44% to 8.60%)by dietary DHA/EPA ratios lower than 1.18,and then increased slightly.Quadratic analysis(y=5.199 6x²-15.652x+20.866;R²=0.634 8,x=dietary DHA/EPA ratios,y=liver lipid content)suggests the optimum DHA/EPA ratio is 1.51 based on liver lipid deposition.Liver and muscle EPA contents were reduced linearly,however,DHA contents as well as DHA/EPA ratios were elevated linearly by dietary DHA/EPA ratios.Exclusively,total content of n-3 HUFA in both tissues were unaffected by dietary treatments.(3)Among all serum physiological parameters,both total protein and globulin showed their highest values at the DHA/EPA ratio of 1.59,while fish fed diets with DHA/EPA ratios of 0.64,0.97 and 1.59 presented higher albumin content.Lysozyme(LSZ)reached the top in fish fed diet with dietary DHA/EPA ratio of 1.18.Alanine aminotransferase(ALT)remained unchanged when the dietary DHA/EPA ratios were lower than 1.91,while dietary DHA/EPA ratios higher than 1.18 increased the aspertate aminotransferase(AST)activities by about 65%(P<0.05).In conclusion,under the present experimental conditions,based on fish weight gain rate(WGR),quadratic regression analysis(y=-31.066x²+77.26x+76.541;R²=0.957 4,x=dietary DHA/EPA ratios,y=weight gain rate)shows that the optimum DHA/EPA ratio for juvenile starry flounder[initial body weight,(31.70±0.12)g]is 1.24.

Abstract:In order to get an evaluation of the nutritive values of five food animals,the nutrient composition was investigated for nauplii of Anemia,enriched Anemia,Calanus sinicus,Acanthomysis brevirostis and Ampithoe valida.The contents of moisture,ash,crude protein,crude fat,amino acids and fatty acids in those food animals were determined by adopting national standard method.The results showed as follows:the contents of moisture,ash,crude fat and crude protein in five food animals were 87.83% to 92.89%,1.69% to 4.12%(fresh),0.55% to 1.36%(fresh)and 4.25% to 8.74%(fresh)respectively.The highest contents of crude fat in nauplii of Anemia,and the highest crude protein content in A.brevirostis were observed in this study.Each food animal contained 20 amino acids,reasonable structure and rich in essential amino acids,which had a decreasing tendency in five food animals of amino acid contents and evaluation as A.brevirostis >nauplii of Anemia >enriched Anemia >C.sinicus >A.valida.All the food animals contained 23 fatty acids,and polyunsaturated fatty acid(PUFA)content was 23.21% to 41.03%, which had a decreasing tendency in in five food animals as C.sinicus >A.brevirostis >A.valida >nauplii of Anemia >enriched Anemia,(P>0.05).EPA and DHA were rarely detected in nauplii of Anemia,but C.sinicus,A.valida and A.brevirostis rich in EPA and DHA.In conclusion,the five food animals are rich in protein and fat,all meet the basic nutritional needs of animal feed,especially C.sinicus and A.brevirostis.

Abstract:In this study,in order to explore a new method and formation mechanism of inducing androgenesis haploid,Paramisgurnus dabryanus was treated only by cold-shock without egg inactivation to induce androgenesis haploid,and the early development,chromosome number and cytology observation of embryos were analyzed.Results were as follows:early development of the embryos showed that the hatching rate of the 0 ℃ and 3 ℃ groups was 0.83% and 57.42% respectively,which was significantly different(P<0.05),and all of them showed haploid syndrome.Ploidy idenfication showed that the chromosome number of the 0 ℃ group ranged from 18 to 27,haploid rate was 81.40%,and the chromosome number of the 3 ℃ group ranged from 20 to 30,haploid rate was 68.97%.Cytology observation of the split embryo showed:in the 3 ℃ group,60 min after fertilization,egg nucleus and the second polar body were on the embryo surface,and were about to eliminate together.In conclusion,P.dabryanus androgenesis haploid could be successfully induced when treated at 3 ℃ for 60 min,and the cytology mechnism may be that the nucleus and the second polar body were spawned together.Results of this study not only enriched the theory of fish sex control,but also provided new way for the all-male production.

Abstract:Based on the monthly samples caught by bottom trawls in the Beibu Gulf of the South China Sea from November 2008 to September 2009,the biological information and stomach contents were collected for analysis of feeding habits.The stable isotope analysis was also used to study the prey category,trophic level and ontogenetic feeding habits of P.edita.The results showed that P.edita preyed widely in the Beibu Gulf,including twenty-three species such as small pelagic and bottom fishes,benthic crustacean,cephalopoda and so on.Among them,fishes account for 79.74%.The dominant fish prey was Bregmaceros macclellandii which appeared every month,comprising 58.38% of total food weight.Crustacean and cephalopoda account for 10.86% and 6.97%.The trophic shift was found in P.edita according to the index of relative importance(IRI%).Those P.edita whose standard length ranged from 30 mm to 59 mm mainly feed on small zooplankton,while those with standard length greater than or equal to 60 mm mainly feed on large forage fish and benthic invertebrates(shrimps,crabs,and cephalopodas).The average repletion index significantly changed with the standard length(P<0.05),so did the gonad maturity index(P<0.05).The vacuity coefficient also significantly changed with the standard length(P<0.05),but there was no significant difference in gonad maturity alteration.The nitrogen stable isotope ratios were from 12.009×10^-3 to 16.007×10^-3.The trophic levels of P.edita calculated from δ¹⁵N did not differ notably with the standard length and month shift.The average trophic level was calculated by prey weight percentage and δ¹⁵N and it was 3.1 and 3.7,respectively.

Abstract:The swimming crab,Portunus trituberculatus,is a commercially important fisheries resource and mariculture species in East Asian countries.Female crab with fully developed ovary is considered as the highly nutritious seafood.Therefore,the decline in natural stock and increase in market demands have driven substantial aquaculture interests for this crab species since 1990's.However,our previous studies have shown pond-reared females generally have poor ovarian development and lower nutrition value compared to wild females,which leads to low percentage of high quality females with fully developed ovaries from pond culture of P.trituberculatus.Fattening with high quality live food,such as trash fish and clam,has proven to be an effective practice for the improvement of crab ovarian development and nutritional composition.Unfortunately,to date,optimal fattening period is unclear for female P.trituberculatus.The present study was conducted to investigate the effects of fattening period on ovarian development and nutritional quality of female swimming crab by fattening culture and biochemical analysis.The results showed that gonadosomatic index(GSI)increased significantly during the 90-day fattening period while the trend of "low-high-low" was found in muscular yield and total edible yield.The highest total edible yield(more than 42%)was in the females fattened for 30-60 days.Fattening period did not affect the proximate composition of muscle,but the highest protein,lipid and carbohydrate contents,together with the lowest moisture contents in ovary and hepatopancreas,were found in the females with 60 days fattening.The cholesterol percentage(%total lipids)in ovary and hepatopancreas decreased significantly during the course of 0-60 days fattening while phospholipids levels of ovary and hepatopancreas increased significantly during 60-90 days fattening.For the different edible parts,hepatopancreas had the highest triacyglycerol levels.As for the fatty acid composition,the increasing trend was found in mono-unsaturated fatty acids(MUFA)for ovary and hepatopancreas while the trend of "high-low-high" was found in poly-unsaturated fatty acids(PUFA)and highly unsaturated fatty acids(HUFA).Muscle contained significant higher percentage of HUFA than ovary and hepatopancreas.Total amino acids(TAA)of ovary increased dramatically during the early period of fattening while the contents of three sweet amino acids gradually increased during the process of 90-day-fattening.Essential amino acid scores(EAAS)of ovary and muscle were greater than 100 for all essential amino acids(EAA)after females fattened for 60-90 days,which indicated no limited amino acid was found in ovary and muscle.For fattening females,EAA/TAA ratios of ovary and muscle were close to or higher than FAO/WHO/UNU recommended values for healthy food.In conclusion,the fattening would not only improve the total edible yield,but also optimize the nutritional values for female P.trituberculatus.Our results suggested the appropriate fattening period was approximately 60 days for pond-reared females post puberty molting.Those results would not only provide valuable information for the future culture and fattening of female P.trituberculatus,but also facilitate the further study on the nutritional regulation of female quality.

Abstract:Acute viral necrosis virus(AVNV)was reported as the causative agent responsible for summer mass mortality of adult Zhikong scallop(Chlamys farreri),which is widely cultured along northern China coast.In this study,the open reading frame(ORF)86 of AVNV was successfully amplified based on the specific primers designed according to the complete genome sequences of AVNV.The gene encoded by ORF86 in AVNV was named IAP-86 in this study,since the homology of ORF 86 was firstly identified as encoding inhibitor of apoptosis protein(IAP)in baculovirus.We subcloned the amplified PCR fragments of IAP-86 into the prokaryotic expression vector pET32a(+),and obtained the recombinant plasmid pET32a-IAP86 through the linking of IAP-86 gene to pET32a(+)plasmid.Then the recombinant plasmids were transformed into E.coil BL21(DE3)strain and expressed under the induction of IPTG.The SDS-PAGE analysis showed that the molecular mass of the induced recombinant protein was about 40 ku.The expressed protein was verified through the Western-blotting and mass spectrometry analysis.Then the recombinant protein was purified with Co²⁺ purification column and marked with FITC.We found IAP-86 could combine with the nucleus and the cytoplasm and inhibit the apoptosis of blood lymphocyte cell of C.farreri through coincubation of them.The cell apoptosis was inhibited by the recombinant of IAP-86 according to the result of apoptosis experiment,and the rate of apoptosis inhibition was about 7%.IAP-86 was successfully expressed through the prokaryotic expression system in our study,and the expressed protein was found to be able to inhibit cell apoptosis of blood lymphocyte of C.farreri.These results provide theoretical and experimental basis for studying the infection mechanism of AVNV.

Abstract:In order to elucidate the mechanism of desiccation-stress adaptability in Sargassum thunbergii,the molecular responsive process under desiccation stress was studied on the level of gene expression using the RNA-seq technology.A total of 17 532 085 and 14 479 820 clean reads were obtained in the control group CO1 and in the treatment group DR2(3 h desiccation stress)respectively,and 20 966 and 20 588 genes were detected in CO1 and DR2,respectively.A total of 476 genes were expressed differently between CO1 and DR2,among which 135(28.36%)and 341(71.64%)were respectively up-and down-regulated expressed in DR2 compared to CO1.Gene Ontology(GO)enrichment analysis assigned the 476 differently expressed genes(DEG)to 915 GO terms,among which 143 GO terms containing the up-regulated genes while 860 GO terms containing down-regulated genes.Pathway enrichment analysis showed 104 pathways were enriched.The up-regulated genes were involved in 10 pathways,whereas the down-regulated gens were involved in 101 pathways.The DEGs code the Hsp family,antioxidant enzyme system,protein synthesis,process and degradation related factors and so on.The above results indicated that the response process to desiccation stress in S.thunbergii was complex,involving many metabolic pathways and signal transduction pathways.

Abstract:Three growth models,Logistic,Gompertz and von Bertalanffy,were used as the candidates for fitting the growth model of eight morphometric traits of Portunus trituberculatus "Zhongning No.1" at six months,including body weight,body length,full carapace width,carapace width,body height,meropodit length of the claw,fixed finger length of claw and meropodit length of the first peraeopod.The paper aimed to establish the optimum growth equation of morphometric traits and study the growth regulation of it.Growth parameters embraced in foregoing models were estimated by Levenberg-Marquardt iteration method.Results showed that Logistic model is the best model to describe the growth of body weight of P.trituberculatus,with squared multiple correlation coefficient R² reaching 0.999.However,the other morphometric traits were best confirmed by von Bertalanffy model,and the squared multiple correlation coefficient R² ranged from 0.990 to 0.994.All optimum growth models of varying morphometric traits was significant(ANOVA,P<0.01).The growth limits computed by optimum growth models were,body weight 231.44 g,body length 84.45 mm,full carapace width 164.44 mm,carapace width 128.47 mm,body height 43.69 mm,and meropodit length of the claw 59.96 mm,fixed finger length of claw 90.89 mm,meropodit length of the first peraeopod 37.20 mm.What's more,the fast growth intervals and growth inflection points of varying morphometric traits were:body weight 2.14-3.91 months and 3.02 months,body length 0-2.05 months and 0.87 months,full carapace width 0-2.14 months and 0.93 months,carapace width 0-2.07 months and 0.94 months,body height 0-2.14 months and 1.04 months,meropodit length of the claw 0-2.3 months and 1.09 months,fixed finger length of claw 0-2.35 months and 1.11 months,and meropodit length of the first peraeopod 0-2.12 months and 0.98 months.The growth rate,the growth acceleration,the relative growth rate and the absolute growth rate were different among varying morphometric traits.In short,the process of body weight trait growth conformed to the characteristic of "slow-fast-slow",the other morphometric traits are "fast-slow".The above results can provide some references for the selective breeding and production of P.trituberculatus "Zhongning No.1".

Abstract:In order to study the selectivity of Scomberomorus niphonius gillnet mesh systematically,four different meshes of 110,115,120 and 125 mm were tested during fishing operation from April to May 2013.Selectivity model curves and body shape coefficients were used to analyze the mesh selectivity.Results showed that ①The gillnet tested had good selectivity,the dominant species were Scomberomorus niphonius and Sebastes fuscescens with IRI values of 18 626.8 and 2 740.1,respectively.②Gamma model obtained the best goodness-of-fit with the selectivity model curves among the common models tested.③The formulae describing the relationship between mesh size(α)and fork length(l)or body weight(W)were α=0.092 7l and α=4.59W^1/3,respectively.④The formula describing the relationship between mesh size and maximum perimeter of body section(S)was α=0.224S-5.37.⑤The optimum meshes for catching 3-4 ages of S.niphonius were estimated to be 120.4 and 121.5 mm respectively by Gamma selective curve and the afore-mentioned formulae.The optimum meshes for different ages of S.niphonius were also calculated based on the historical fishing data.

Abstract:In the present study,we investigated how temperature stress affected gene expressions of sea cucumber Apostichopus japonicas.Major yolk protein(MYP)gene was selected as a candidate indicator from our former pilot screening study on cold-resistant genes.Two isoforms of MYP namely,MYP1 and MYP2,were both involved,to enhance the reliability of inferences drawn by the current study.Temporal expression features of the two MYPs were surveyed for nine developmental stages(fertilized egg,blastula,gastrula,early auricularia,auricularia,late auricularia,doliolaria,pentactula,juvenile)via RT-PCR.Tissue distribution for adult A.japonicas was studied for seven tissues(respiratory tree,coelomocyte,intestine,muscle,body wall,testis,ovary).Expression profiles of the two MYPs corresponding to a long-term High/Low temperature treatment and a temporal acute cold shock treatment were investigated respectively,with intestine as the target tissue.The two MYPs presented similarities for temporal expression and tissue distribution:gradually enhanced expression from doliolarias stage to juvenile stage;and tissue-ubiquitous(but not in coelomic fluid)expression with greatest abundance in intestine.Interestingly,although the expressions of MYP presented a negative linear relationship with the constant environmental temperature(six times higher for 4 ℃ compared to 20 ℃),a sharp cold shock treatment significantly suppressed them.

Abstract:This article describes astaxanthin production methods and the latest research progress of the biological activity.It summarizes the current industry processing and techniques,such as the extraction from aquatic byproducts,pluvialis algae and Phaffia yeast.Haematococcus pluvialis is the most ideal biogenetic derivation because of the highest natural astaxanthin.Astaxanthin biological activity and applications,such as anti—oxidation,anti—inflammatory,anti—infective,anti—tumor,anti—fatigue,prevention of osteoporosis were also introduced.Pharmacology and toxicology study shows that astaxanthin not only can be used as the bait additives in aquatic farming,but also has a wide application in food,drugs,cosmetics,and high value nutritional health products,so it has great market potential.Finally,the article made summary and outlook of using H.pluvialis to produce astaxathin,which has great meanings for the further study of H.pluvialis.