Unfavorable fishy odour is an inevitable problem in aquatic products. In the present study, headspace solid-phase mi- croextraction gas chromatography mass spectrometry （HS-SPME-GC-MS） analysis of volatiles from unt...Unfavorable fishy odour is an inevitable problem in aquatic products. In the present study, headspace solid-phase mi- croextraction gas chromatography mass spectrometry （HS-SPME-GC-MS） analysis of volatiles from untreated samples and three deodorized samples （under the optimal conditions） ofPaphia undulata enzymatic hydrolysate revealed that the compounds contrib- uting to the distinctive odor were 1-octen-3-ol, n-hexanal, n-heptanal, 2,4-heptadienal, and 2,4-decadienal, whereas n-pentanal, n-octanal, n-octanol, benzaldehyde, 2-ethylfuran and 2-pentylfuran were the main contributors to the aromatic flavor. The deodoriz- ing effects of activated carbon （AC） adsorption, yeast extract （YE） masking and tea polyphenol （TP） treatment on a P. undulata en- zymatic hydrolysate were investigated using orthogonal experiments with sensory evaluation as the index. The following optimized deodorization conditions were obtained： AC adsorption （35 mg mL-1, 80℃, 40 rain）, YE masking （7 mgmL l, 45 ℃, 30 min） and TP treatment （0.4mgmL-l, 40℃, 50min）. AC adsorption effectively removed off-flavor volatile aldehydes and ketones. YE masking modified the odor profile by increasing the relative contents of aromatic compounds and decreasing the relative contents of aldehydes and ketones. The TP treatment was not effective in reducing the odor score, but it significantly reduced the relative content of alde- hydes while increasing that of alkanes. It is also notable that TP effectively suppressed trimethylamine （TMA） formation in a P. un- dulate hydrolysate solution for a period of 72 h.展开更多
P. textile is an important aquaculture species in China and is mainly distributed in Fujian, Guangdong, and Guangxi Provinces. In this study, an HSP20 c DNA designated Pt HSP20 was cloned from P. textile. The full-len...P. textile is an important aquaculture species in China and is mainly distributed in Fujian, Guangdong, and Guangxi Provinces. In this study, an HSP20 c DNA designated Pt HSP20 was cloned from P. textile. The full-length c DNA of Pt HSP20 is 1 090 bp long and contains a 5′ untranslated region(UTR) of 93 bp, a 3′ UTR of 475 bp, and an open reading frame(ORF) of 522 bp. The Pt HSP20 c DNA encodes 173 amino acid residues and has a molecular mass of 20.22 k Da and an isoelectric point of 6.2. Its predicted amino acid sequence shows that Pt HSP20 contains a typical α-crystallin domain(residues 77–171) and three polyadenylation signal-sequences at the C-terminus. According to an amino acid sequence alignment, Pt HSP20 shows moderate homology to other mollusk s HSPs. Pt HSP20 m RNA was present in all of the test tissues including the heart, digestive gland, adductor muscle, gonad, gill, and mantle, with the highest concentration found in the gonad. Under the stress of high temperature, the expression of Pt HSP20 m RNA was down-regulated in all of the tissues except the adductor muscle and gonad.展开更多
Low molecular weight peptide (LMWP) was prepared from clam Paphia undulate and its antiaging effect on D-galactose-induced acute aging in rats, aged Kunming mice, ultraviolet-exposed rats, and thermally injured rats w...Low molecular weight peptide (LMWP) was prepared from clam Paphia undulate and its antiaging effect on D-galactose-induced acute aging in rats, aged Kunming mice, ultraviolet-exposed rats, and thermally injured rats was investigated. P. undulate flesh was homogenized and digested using papain under optimal conditions, then subjected to Sephadex G-25 chromatography to isolate the LMWP. Administration of LMWP significantly reversed D-galactose-induced oxidative stress by increasing the activities of glutathione peroxidase (GPx) and catalase (CAT), and by decreasing the level of malondialdehyde (MDA). This process was accompanied by increased collagen synthesis. The LMWP prevented photoaging and promoted dermis recovery and remission of elastic fiber hyperplasia. Furthermore, treatment with the LMWP helped to regenerate elastic fibers and the collagen network, increased superoxide dismutase (SOD) in the serum and significantly decreased MDA. Thermal scald-induced inflammation and edema were also relieved by the LWMP, while wound healing in skin was promoted. These results suggest that the LMWP from P. undulate could serve as a new antiaging substance in cosmetics.展开更多
Catalase is an important antioxidant protein that can protect organisms against various forms of oxidative damage by eliminating hydrogen peroxide. In this study, the catalase c DNA of Paphia textile（Pt CAT） was clo...Catalase is an important antioxidant protein that can protect organisms against various forms of oxidative damage by eliminating hydrogen peroxide. In this study, the catalase c DNA of Paphia textile（Pt CAT） was cloned using RTPCR and rapid amplification of c DNA ends（RACE）. Pt CAT is 1 921 bp long and consists of a 5′-UTR of 50 bp, a 3′-UTR of 349 bp, and an ORF of 1 542 bp that encodes 513 amino acids with a molecular weight of 58.4 k D and an estimated isoelectric point of 8.2. Sequence alignment indicated that Pt CAT contained a highly conserved catalytic signature motif（^（61）FNRERIPERVVHAKGAG^（77））, a proximal heme-ligand signature sequence（^（352）RLFSYSDP^（359））, and three catalytic amino acid residues（H^（72）, N^（145）, and Y^（356））. Pt CAT also contains two putative N-glycosylation sites（^（34）NKT^（36） and ^（437）NFT^（439）） and a peroxisome-targeting signal（^（511）AQL^（513））. Furthermore, Pt CAT shares 53%–88% identity and 29%–89% similarity with other catalase amino acid sequences. Pt CAT m RNA was present in all tested organs, including the heart, digestive gland, adductor muscle, gonad, gill, and mantle, but its expression was highest in the digestive gland. High-temperature-induced stress produced two expression patterns of Pt CAT m RNA： first, an initial up-regulation followed by a down-regulation in the heart, digestive gland, and gonad and, second, consistent down-regulation in all other organs. These results demonstrate that Pt CAT is a typical member of the catalase family and might be involved in the responses to harmful environmental factors.展开更多
Increasingly,exogenous stressors such as pathogen infections,variable water conditions,and pollution are resulting in high mortality of Paphia undulata,deleteriously affecting the quality of clam harvests.The foot is ...Increasingly,exogenous stressors such as pathogen infections,variable water conditions,and pollution are resulting in high mortality of Paphia undulata,deleteriously affecting the quality of clam harvests.The foot is a burrowing organ in clams.Physical damage and constant contact with the external environment cause the foot to be highly sensitive to pathogen invasion and water condition variation.In the present study,the foot tissue transcriptome was analyzed to identify genes involved in immune and stress responses.The P.undulata transcriptome included 5 286 668 078 bp reads generated by Illumina Hiseq 2000 sequencing and were assembled into 1 785 226 contigs by de novo method.The contigs were clustered into 99 339 transcripts and further grouped into 60 201 unigenes.Of them,22 260 unigenes were successfully annotated using public databases.Twelve genes that were response to immune and stress were identified with abundant expression levels,including heat shock protein 70,cold shock protein,complement C3,cathepsin L,ubiquitin carboxyl-terminal hydrolase L5,and translationally controlled tumor protein.Furthermore,566 unigenes were found homologous to genes involved in the immune response systems of pathogen discrimination,signal transduction,and immune effector,such as lectins,toll-like receptors,complement pathway,toll-like receptor signaling pathway,heat shock proteins,antioxidant enzymes,lysozymes,and mucins,indicating that P.undulata could have a complete set of innate immune mechanisms.In addition,4 270 microsatellite markers(SSRs)were identified from 60 201 unigenes,of which trinucleotide repeats were most abundant and 16 SSRs were tested to be polymorphic.The present study provides a new insight into innate immunity and stress response mechanisms in P.undulata.展开更多
Substrate is an important abiotic factor for burrowing shellfish,as it not only provides them with shelter,but also impose significant effect on their physiological metabolism.However,the physiological responses of bu...Substrate is an important abiotic factor for burrowing shellfish,as it not only provides them with shelter,but also impose significant effect on their physiological metabolism.However,the physiological responses of burrowing clams within various substrates get less attention due to difficulty in carrying out physiological tests in buried conditions.Consequently,this study investigated the burrowing behavior,feeding physiology and energy budget of Paphia undulata,which is an important aquaculture bivalve species in south China.The clams were exposed to mud and sand substrates with variable physical properties in the laboratory,to determine the suitable substrate conditions for this species.The results showed that the percentage of burrowing clams,digging index,burrowing time,burrowing depth and scope for growth(SFG)were higher in mud substrates with≥40%water content.Likewise,burrowing percentage,digging index,and burrowing depths were higher in substrates with≤40%sand content.Moreover,the burrowing depth had significant effect on the feeding physiology and SFG of P.undulata as clams burrowed at 6.3±1.8 cm had higher clearance rates and SFG as compared to other buried depths.This study further revealed that low water content in the sediment inhibited physiological performances of P.undulata by impairing feeding or absorption,hence reducing the SFG.In conclusion,mud substrate with≥40%water content or with≤40%sand content is suitable for proper burrowing and growth of P.undulata.Our findings therefore provide fundamental knowledge that will be applicable in the improvement of bottom aquaculture and conservation of P.undulata.展开更多
Our study investigated preservation Undulate venus (</span></span><span><span><span style="font-family:""><i></span></span></span><span><sp...Our study investigated preservation Undulate venus (</span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:"">)</span></span></span><span><span><span style="font-family:""> by canning via three treatments </span></span></span><span><span><span style="font-family:"">that </span></span></span><span><span><span style="font-family:"">are canned raw, canned smoked and canned cooked as a healthy product with high nutritional value. Results<span> </span>reported that edible meat of </span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:""> was free from Cu, Pb and Cd as a result of washing process. There was significantly (p < 0.05) higher in moisture content of canned raw compared with other tow treatments </span></span></span><span><span><span style="font-family:"">of </span></span></span><span><span><span style="font-family:"">canned smoked and canned cooked of </span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:"">, and there was significantly reduction of protein content (p < 0.05) in tow treatments </span></span></span><span><span><span style="font-family:"">of </span></span></span><span><span><span style="font-family:"">canned smoked and canned cooked compared with the canned raw. Significant different (p < 0.05) in fat content </span></span></span><span><span><span style="font-family:"">w</span></span></span><span><span><span style="font-family:"">as canned raw < canned smoked < canned cooked. On the other side</span></span></span><span><span><span style="font-family:"">,</span></span></span><span><span><span style="font-family:""> the three treatments of canned shellfish </span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:"">had significant differen</span></span></span><span><span><span style="font-family:"">ce</span></span></span><span><span><span style="font-family:""> (p < 0.05) in content of ash and carbohydrates content. Canned smoked of shellfish </span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:""> showed the lowest value of pH. All treatments of canned shellfish<span> </span></span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:""> were rich in minerals where canned raw treatment was higher in Ca, Fe, Zn, Mg, and Mn. While canned smoked had minerals content lower than canned raw. Lightness (L*) had slightly differen</span></span></span><span><span><span style="font-family:"">ce</span></span></span><span><span><span style="font-family:""> between all treatments </span></span></span><span><span><span style="font-family:"">of </span></span></span><span><span><span style="font-family:"">canned shellfish </span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia</span></i></span></span><span><span><i><span style="font-family:""> <span>undulate</span></span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:"">. Reduction on lightness and redness was noticed at the same time in all treatments of canned shellfish<span> </span></span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia</span></i></span></span><span><span><span style="font-family:""> <i>undulate</i></span></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:"">,</span></span></span><span><span><span style="font-family:""> canned raw had</span></span></span><span><span><span style="font-family:""> the </span></span></span><span><span><span style="font-family:"">highest value of lightness (L*), and redness (a*). Canned smoked had the highest value of hardness followed by canned raw then canned cook. Slightly significant difference (p < 0.05) was noticed between three treatments in sensory properties, data showed that all panelists prefer</span></span></span><span><span><span style="font-family:"">red</span></span></span><span><span><span style="font-family:""> canned cooked than raw canned and canned smoked, degree of canned cooked was excellent.展开更多
Paphia textile is an economically important bivalve cultured in southeastern China.The feet,as the main edible part of P.textile,vary in color from white to orange.Previous studies have suggested that the orange feet ...Paphia textile is an economically important bivalve cultured in southeastern China.The feet,as the main edible part of P.textile,vary in color from white to orange.Previous studies have suggested that the orange feet of P.textile contain higher levels of carotenoids than the white feet,but the kinds of carotenoids are not known.The pigments identified in this study can facilitate further analysis of their underlying molecular mechanism and enable the breeding of P.textile with high carotenoid content.The pigments were extracted from the orange feet of P.textile by an acetone extraction method,and then,the extracted pigments were analyzed by liquid chromatography-mass spectrometry(LC-MS).Moreover,the MS analysis was carried out with an electrospray ionization(ESI)source in the positive(ESI+)and negative(ESI-)ion modes.A total of 47 substances were detected,including 9 terpenoids,7 amino acids and peptides,13 lipids,9 organic acids,2 types of vitamin A and 7 other substances.Furthermore,β-doradecin(3’-hydroxy-3,4-diketo-β-carotene)was identified as the main pigment in the feet.This is the first report of the presence ofβ-doradecin,a type of carotenoid,in bivalves.展开更多
The Heat shock proteins(HSPs)are a group of molecular chaperones that play a crucial role in cell response to various stresses.A full-length cDNA of the heat shock protein 90(PuHsp90)was cloned and sequenced from the ...The Heat shock proteins(HSPs)are a group of molecular chaperones that play a crucial role in cell response to various stresses.A full-length cDNA of the heat shock protein 90(PuHsp90)was cloned and sequenced from the clam Paphia undulata.Phylogenetic analysis revealed that PuHsp90 grouped with the Hsp90 from other metazoan species.Expression of PuHsp90 was highly detected in the gonad,followed by digest gland,gills and heart but was found poorly expressed in mantle,adductor muscle and hemocytes.After a heat shock stress at 32℃up-regulation of PuHsp90 was detected in the mantle,adductor muscle,gills and hemocytes.Maximal expression levels occurred at 4 h after the heat shock and up-regulation is indicative of protein denaturation and of an increase in energy consumption.In contrast after the heat shock,PuHsp90 was continuously down-regulated in the digestive gland and in the gonad suggesting modifications of the biochemical pathways and energy budgets involved in the synthesis of other protein,such as catalase and of other Hsp proteins.These results reveal that PuHsp90 may play an important role in the clam response to a temperature stress.展开更多
基金supported by the Public Science and Technology Research Funds Projects of Ocean (No.201305018)the National Key Technology Research and Development Program for the 12th Five-Year Plan (No.2012BAD33B10)+3 种基金the National Natural Science Foundation of Guangdong, China (Nos. 2014A 030310351 and 2014A030310338)the Innovative Development of Marine Economy Regional Demonstration Projects of Guangdong (Nos.SZHY2012-B01-004 and GD2013-B03-001)the Science and Technology Planning Project of Guangdong Province, China (Nos.2013B 090800002 and 2015B090904003)the National Science Foundation for Young Scientists of China (No.31101271)
文摘Unfavorable fishy odour is an inevitable problem in aquatic products. In the present study, headspace solid-phase mi- croextraction gas chromatography mass spectrometry （HS-SPME-GC-MS） analysis of volatiles from untreated samples and three deodorized samples （under the optimal conditions） ofPaphia undulata enzymatic hydrolysate revealed that the compounds contrib- uting to the distinctive odor were 1-octen-3-ol, n-hexanal, n-heptanal, 2,4-heptadienal, and 2,4-decadienal, whereas n-pentanal, n-octanal, n-octanol, benzaldehyde, 2-ethylfuran and 2-pentylfuran were the main contributors to the aromatic flavor. The deodoriz- ing effects of activated carbon （AC） adsorption, yeast extract （YE） masking and tea polyphenol （TP） treatment on a P. undulata en- zymatic hydrolysate were investigated using orthogonal experiments with sensory evaluation as the index. The following optimized deodorization conditions were obtained： AC adsorption （35 mg mL-1, 80℃, 40 rain）, YE masking （7 mgmL l, 45 ℃, 30 min） and TP treatment （0.4mgmL-l, 40℃, 50min）. AC adsorption effectively removed off-flavor volatile aldehydes and ketones. YE masking modified the odor profile by increasing the relative contents of aromatic compounds and decreasing the relative contents of aldehydes and ketones. The TP treatment was not effective in reducing the odor score, but it significantly reduced the relative content of alde- hydes while increasing that of alkanes. It is also notable that TP effectively suppressed trimethylamine （TMA） formation in a P. un- dulate hydrolysate solution for a period of 72 h.
基金Supported by the Research Council of Norway(No.229572/F11)the Foundation for the Innovation Research Team of Jimei University(No.2010A02)the Chinese Students’ Innovation and Business Training Program
文摘P. textile is an important aquaculture species in China and is mainly distributed in Fujian, Guangdong, and Guangxi Provinces. In this study, an HSP20 c DNA designated Pt HSP20 was cloned from P. textile. The full-length c DNA of Pt HSP20 is 1 090 bp long and contains a 5′ untranslated region(UTR) of 93 bp, a 3′ UTR of 475 bp, and an open reading frame(ORF) of 522 bp. The Pt HSP20 c DNA encodes 173 amino acid residues and has a molecular mass of 20.22 k Da and an isoelectric point of 6.2. Its predicted amino acid sequence shows that Pt HSP20 contains a typical α-crystallin domain(residues 77–171) and three polyadenylation signal-sequences at the C-terminus. According to an amino acid sequence alignment, Pt HSP20 shows moderate homology to other mollusk s HSPs. Pt HSP20 m RNA was present in all of the test tissues including the heart, digestive gland, adductor muscle, gonad, gill, and mantle, with the highest concentration found in the gonad. Under the stress of high temperature, the expression of Pt HSP20 m RNA was down-regulated in all of the tissues except the adductor muscle and gonad.
基金Supported by the Knowledge Innovation Program of Chinese Academy of Sciences(No.KZCX2-EW-Q214)the Comprehensive Strategic Cooperation Programs between Guangdong Province and Chinese Academy of Sciences(Nos.2011A090100008,2009B091300018,2010B090300027)the Marine Fisheries Technology Promotion Special Program of Guangdong Province,China(No.A2009009-035(a))
文摘Low molecular weight peptide (LMWP) was prepared from clam Paphia undulate and its antiaging effect on D-galactose-induced acute aging in rats, aged Kunming mice, ultraviolet-exposed rats, and thermally injured rats was investigated. P. undulate flesh was homogenized and digested using papain under optimal conditions, then subjected to Sephadex G-25 chromatography to isolate the LMWP. Administration of LMWP significantly reversed D-galactose-induced oxidative stress by increasing the activities of glutathione peroxidase (GPx) and catalase (CAT), and by decreasing the level of malondialdehyde (MDA). This process was accompanied by increased collagen synthesis. The LMWP prevented photoaging and promoted dermis recovery and remission of elastic fiber hyperplasia. Furthermore, treatment with the LMWP helped to regenerate elastic fibers and the collagen network, increased superoxide dismutase (SOD) in the serum and significantly decreased MDA. Thermal scald-induced inflammation and edema were also relieved by the LWMP, while wound healing in skin was promoted. These results suggest that the LMWP from P. undulate could serve as a new antiaging substance in cosmetics.
基金The National Natural Science Foundation of China under contract No.31172397the New Century Excellent Talents of Fujian Province University under contract No.JA14167the Open Research Fund Program of Fujian Provincial Key Laboratory of Marine Fishery Resources and Eco-environment under contract No.Z814041
文摘Catalase is an important antioxidant protein that can protect organisms against various forms of oxidative damage by eliminating hydrogen peroxide. In this study, the catalase c DNA of Paphia textile（Pt CAT） was cloned using RTPCR and rapid amplification of c DNA ends（RACE）. Pt CAT is 1 921 bp long and consists of a 5′-UTR of 50 bp, a 3′-UTR of 349 bp, and an ORF of 1 542 bp that encodes 513 amino acids with a molecular weight of 58.4 k D and an estimated isoelectric point of 8.2. Sequence alignment indicated that Pt CAT contained a highly conserved catalytic signature motif（^（61）FNRERIPERVVHAKGAG^（77））, a proximal heme-ligand signature sequence（^（352）RLFSYSDP^（359））, and three catalytic amino acid residues（H^（72）, N^（145）, and Y^（356））. Pt CAT also contains two putative N-glycosylation sites（^（34）NKT^（36） and ^（437）NFT^（439）） and a peroxisome-targeting signal（^（511）AQL^（513））. Furthermore, Pt CAT shares 53%–88% identity and 29%–89% similarity with other catalase amino acid sequences. Pt CAT m RNA was present in all tested organs, including the heart, digestive gland, adductor muscle, gonad, gill, and mantle, but its expression was highest in the digestive gland. High-temperature-induced stress produced two expression patterns of Pt CAT m RNA： first, an initial up-regulation followed by a down-regulation in the heart, digestive gland, and gonad and, second, consistent down-regulation in all other organs. These results demonstrate that Pt CAT is a typical member of the catalase family and might be involved in the responses to harmful environmental factors.
基金Supported by the Open Program of Key Laboratory of Cultivation and High-value Utilization of Marine Organisms in Fujian Province(No.2015fjscq05)the Guangdong Province Program,China(Nos.2014B020202011,2016A020208011,A201601A04,20168020233005,2016TQ03N905)+1 种基金the Science and Technology Planning Project of Guangdong Province,China(No.2017B030314052)the China Agriculture Research System(No.CARS-49)
文摘Increasingly,exogenous stressors such as pathogen infections,variable water conditions,and pollution are resulting in high mortality of Paphia undulata,deleteriously affecting the quality of clam harvests.The foot is a burrowing organ in clams.Physical damage and constant contact with the external environment cause the foot to be highly sensitive to pathogen invasion and water condition variation.In the present study,the foot tissue transcriptome was analyzed to identify genes involved in immune and stress responses.The P.undulata transcriptome included 5 286 668 078 bp reads generated by Illumina Hiseq 2000 sequencing and were assembled into 1 785 226 contigs by de novo method.The contigs were clustered into 99 339 transcripts and further grouped into 60 201 unigenes.Of them,22 260 unigenes were successfully annotated using public databases.Twelve genes that were response to immune and stress were identified with abundant expression levels,including heat shock protein 70,cold shock protein,complement C3,cathepsin L,ubiquitin carboxyl-terminal hydrolase L5,and translationally controlled tumor protein.Furthermore,566 unigenes were found homologous to genes involved in the immune response systems of pathogen discrimination,signal transduction,and immune effector,such as lectins,toll-like receptors,complement pathway,toll-like receptor signaling pathway,heat shock proteins,antioxidant enzymes,lysozymes,and mucins,indicating that P.undulata could have a complete set of innate immune mechanisms.In addition,4 270 microsatellite markers(SSRs)were identified from 60 201 unigenes,of which trinucleotide repeats were most abundant and 16 SSRs were tested to be polymorphic.The present study provides a new insight into innate immunity and stress response mechanisms in P.undulata.
基金Supported by the Guangxi Science and Technology Base and Talent Special Project (No.AD23026114)。
文摘Substrate is an important abiotic factor for burrowing shellfish,as it not only provides them with shelter,but also impose significant effect on their physiological metabolism.However,the physiological responses of burrowing clams within various substrates get less attention due to difficulty in carrying out physiological tests in buried conditions.Consequently,this study investigated the burrowing behavior,feeding physiology and energy budget of Paphia undulata,which is an important aquaculture bivalve species in south China.The clams were exposed to mud and sand substrates with variable physical properties in the laboratory,to determine the suitable substrate conditions for this species.The results showed that the percentage of burrowing clams,digging index,burrowing time,burrowing depth and scope for growth(SFG)were higher in mud substrates with≥40%water content.Likewise,burrowing percentage,digging index,and burrowing depths were higher in substrates with≤40%sand content.Moreover,the burrowing depth had significant effect on the feeding physiology and SFG of P.undulata as clams burrowed at 6.3±1.8 cm had higher clearance rates and SFG as compared to other buried depths.This study further revealed that low water content in the sediment inhibited physiological performances of P.undulata by impairing feeding or absorption,hence reducing the SFG.In conclusion,mud substrate with≥40%water content or with≤40%sand content is suitable for proper burrowing and growth of P.undulata.Our findings therefore provide fundamental knowledge that will be applicable in the improvement of bottom aquaculture and conservation of P.undulata.
文摘Our study investigated preservation Undulate venus (</span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:"">)</span></span></span><span><span><span style="font-family:""> by canning via three treatments </span></span></span><span><span><span style="font-family:"">that </span></span></span><span><span><span style="font-family:"">are canned raw, canned smoked and canned cooked as a healthy product with high nutritional value. Results<span> </span>reported that edible meat of </span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:""> was free from Cu, Pb and Cd as a result of washing process. There was significantly (p < 0.05) higher in moisture content of canned raw compared with other tow treatments </span></span></span><span><span><span style="font-family:"">of </span></span></span><span><span><span style="font-family:"">canned smoked and canned cooked of </span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:"">, and there was significantly reduction of protein content (p < 0.05) in tow treatments </span></span></span><span><span><span style="font-family:"">of </span></span></span><span><span><span style="font-family:"">canned smoked and canned cooked compared with the canned raw. Significant different (p < 0.05) in fat content </span></span></span><span><span><span style="font-family:"">w</span></span></span><span><span><span style="font-family:"">as canned raw < canned smoked < canned cooked. On the other side</span></span></span><span><span><span style="font-family:"">,</span></span></span><span><span><span style="font-family:""> the three treatments of canned shellfish </span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:"">had significant differen</span></span></span><span><span><span style="font-family:"">ce</span></span></span><span><span><span style="font-family:""> (p < 0.05) in content of ash and carbohydrates content. Canned smoked of shellfish </span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:""> showed the lowest value of pH. All treatments of canned shellfish<span> </span></span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia undulate</span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:""> were rich in minerals where canned raw treatment was higher in Ca, Fe, Zn, Mg, and Mn. While canned smoked had minerals content lower than canned raw. Lightness (L*) had slightly differen</span></span></span><span><span><span style="font-family:"">ce</span></span></span><span><span><span style="font-family:""> between all treatments </span></span></span><span><span><span style="font-family:"">of </span></span></span><span><span><span style="font-family:"">canned shellfish </span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia</span></i></span></span><span><span><i><span style="font-family:""> <span>undulate</span></span></i></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:"">. Reduction on lightness and redness was noticed at the same time in all treatments of canned shellfish<span> </span></span></span></span><span><span><span style="font-family:""><i></span></span></span><span><span><i><span style="font-family:"">Paphia</span></i></span></span><span><span><span style="font-family:""> <i>undulate</i></span></span></span><span><span><i><span style="font-family:""></i></span></i></span></span><span><span><span style="font-family:"">,</span></span></span><span><span><span style="font-family:""> canned raw had</span></span></span><span><span><span style="font-family:""> the </span></span></span><span><span><span style="font-family:"">highest value of lightness (L*), and redness (a*). Canned smoked had the highest value of hardness followed by canned raw then canned cook. Slightly significant difference (p < 0.05) was noticed between three treatments in sensory properties, data showed that all panelists prefer</span></span></span><span><span><span style="font-family:"">red</span></span></span><span><span><span style="font-family:""> canned cooked than raw canned and canned smoked, degree of canned cooked was excellent.
基金supported by the National Key Research and Development Program of China (No.2018YFD0901404).
文摘Paphia textile is an economically important bivalve cultured in southeastern China.The feet,as the main edible part of P.textile,vary in color from white to orange.Previous studies have suggested that the orange feet of P.textile contain higher levels of carotenoids than the white feet,but the kinds of carotenoids are not known.The pigments identified in this study can facilitate further analysis of their underlying molecular mechanism and enable the breeding of P.textile with high carotenoid content.The pigments were extracted from the orange feet of P.textile by an acetone extraction method,and then,the extracted pigments were analyzed by liquid chromatography-mass spectrometry(LC-MS).Moreover,the MS analysis was carried out with an electrospray ionization(ESI)source in the positive(ESI+)and negative(ESI-)ion modes.A total of 47 substances were detected,including 9 terpenoids,7 amino acids and peptides,13 lipids,9 organic acids,2 types of vitamin A and 7 other substances.Furthermore,β-doradecin(3’-hydroxy-3,4-diketo-β-carotene)was identified as the main pigment in the feet.This is the first report of the presence ofβ-doradecin,a type of carotenoid,in bivalves.
基金This work was supported by the Open Program of Key Laboratory of Cultivation and High-value Utilization of Marine Organisms in Fujian Province(2015fjscq05)the New Century Excellent Talents of Fujian Province University(No.JA14167).
文摘The Heat shock proteins(HSPs)are a group of molecular chaperones that play a crucial role in cell response to various stresses.A full-length cDNA of the heat shock protein 90(PuHsp90)was cloned and sequenced from the clam Paphia undulata.Phylogenetic analysis revealed that PuHsp90 grouped with the Hsp90 from other metazoan species.Expression of PuHsp90 was highly detected in the gonad,followed by digest gland,gills and heart but was found poorly expressed in mantle,adductor muscle and hemocytes.After a heat shock stress at 32℃up-regulation of PuHsp90 was detected in the mantle,adductor muscle,gills and hemocytes.Maximal expression levels occurred at 4 h after the heat shock and up-regulation is indicative of protein denaturation and of an increase in energy consumption.In contrast after the heat shock,PuHsp90 was continuously down-regulated in the digestive gland and in the gonad suggesting modifications of the biochemical pathways and energy budgets involved in the synthesis of other protein,such as catalase and of other Hsp proteins.These results reveal that PuHsp90 may play an important role in the clam response to a temperature stress.
