Due to extensive morphological plasticity,the taxonomy of Cladophora species remains unclear.As one of the widely distributed species,C.gracilis was reported to hold many varieties,which make it difficult to identify ...Due to extensive morphological plasticity,the taxonomy of Cladophora species remains unclear.As one of the widely distributed species,C.gracilis was reported to hold many varieties,which make it difficult to identify the species.This study explored the morphology diversity of nine C.gracilis samples collected along the coast of western Yellow Sea.Some samples showed extremely varied characteristics,by which one cannot classify them correctly.Hence,18S rDNA and nuclear ribosomal DNA internal transcribed spacer regions(ITS)sequences were employed to delimit species.For 18S rDNA,sequence similarity ranged from 99.6%to 100%.For ITS region,the similarity ranged from 98.7%to 100%.Molecular data strongly suggested that the morphologically heterogeneous samples were actually the same species.Characteristics comparison of the samples revealed that the taxonomy criteria including branching pattern and density,thallus color,height and texture varied widely,influenced by environmental conditions and age of alga.Besides,cell dimensions,as the relatively stable criterion,also exhibited intraspecific variance.Successful application of 18S rDNA and ITS sequences indicated that molecular method can be a powerful assistant as DNA barcodes to traditional morphology taxonomy.展开更多
The antibacterial effect of the crude methanol extracts and purified fractions of Ctadophora glomerata （Linnaeus） Kutzing （Cladophoraceae） against multidrug resistant human pathogen were investigated. The test bac...The antibacterial effect of the crude methanol extracts and purified fractions of Ctadophora glomerata （Linnaeus） Kutzing （Cladophoraceae） against multidrug resistant human pathogen were investigated. The test bacterial strains were Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus faecalis, Escherichia coli and S. typhimurium. Ethanol extract （0.5 mg/mL） of Cladophora glomerata inhibited growth of all the test organisms. Primary detection of active compounds showed that maeroalgae （Cladophora glomerata） containing flavonoids, alkaloids, phenols and tannins. Gas Chromatography-Mass Spectrometry was used to know the compounds which responsible of antibacterial activity and they were g-Pentadecanone that was found to be a major compound （42.67%） followed by 8-Octadecanone （22.43%） and Salicylic acid （20.04%） in addition to 10-hexadecaden （8.01%）. These findings suggest the possibility of using the Cladophora glomerata as a novel source of natural antimicrobial agents in pharmaceutical industries.展开更多
The amylase obtained from Cladophora hutchinsiae was purified by the starch affinity method(11.4-fold and specific activity of 89.7±2.6 U/mg protein)and examined for its biochemical characterization,thermodynamic...The amylase obtained from Cladophora hutchinsiae was purified by the starch affinity method(11.4-fold and specific activity of 89.7±2.6 U/mg protein)and examined for its biochemical characterization,thermodynamic properties,and use in some industrial applications.As a result of SDS-PAGE analysis,the presence of a single band of 66.2 kDa was determined.It was determined that the enzyme showed optimum activity at pH 6.00 and 10℃.In the presence of soluble starch as substrate,Km,Vmax and kcat values were calculated as 1.49±0.03 mg/mL,0.18±0.01 U and 0.003 s−1respectively.The enzyme demonstrated remarkable pH stability.Enzyme activity was investigated in a medium containing some organic solvent and cations.While amylase was inhibited by ethanol,acetonitrile,glycerol,and acetone(10%),no change in activity was observed in the presence of isopropanol.In addition,it was determined that while Cu2+and Hg2+metal ions(5 mM)effectively inhibited the amylase enzyme,Ca2+ion activates the amylase enzyme.The activation energy(Ea)was calculated as at 28.3 kJ mol^(−1).It was also found to be effective in releasing the reducing sugar from different fruit juice and fish feed.The amount of reducing sugar released as a result of incubation of fruit juices with enzyme for 3 h was observed the most in apple juice(from 1658.3±33.8μg/mL to 1945.6±36.7μg/mL)and the increase in the amount of reducing sugar was found to be 1.53 times in fish feed.According to the results obtained from the study,it can be said that the amylase obtained from seaweed can be used in different industrial areas.展开更多
基金Foundation item:The National Natural Science Foundation of China under contract Nos 31670199,31400186 and 30499340the Knowledge Innovation Project of Chinese Academy of Sciences under contract No.KSCX2-YW-Z-018+1 种基金the Scientific Research Plan of Tianjin Municipal Education Committee under contract No.JW1705the Research Fund for Talented Scholars of Tianjin Normal University(2016).
文摘Due to extensive morphological plasticity,the taxonomy of Cladophora species remains unclear.As one of the widely distributed species,C.gracilis was reported to hold many varieties,which make it difficult to identify the species.This study explored the morphology diversity of nine C.gracilis samples collected along the coast of western Yellow Sea.Some samples showed extremely varied characteristics,by which one cannot classify them correctly.Hence,18S rDNA and nuclear ribosomal DNA internal transcribed spacer regions(ITS)sequences were employed to delimit species.For 18S rDNA,sequence similarity ranged from 99.6%to 100%.For ITS region,the similarity ranged from 98.7%to 100%.Molecular data strongly suggested that the morphologically heterogeneous samples were actually the same species.Characteristics comparison of the samples revealed that the taxonomy criteria including branching pattern and density,thallus color,height and texture varied widely,influenced by environmental conditions and age of alga.Besides,cell dimensions,as the relatively stable criterion,also exhibited intraspecific variance.Successful application of 18S rDNA and ITS sequences indicated that molecular method can be a powerful assistant as DNA barcodes to traditional morphology taxonomy.
文摘The antibacterial effect of the crude methanol extracts and purified fractions of Ctadophora glomerata （Linnaeus） Kutzing （Cladophoraceae） against multidrug resistant human pathogen were investigated. The test bacterial strains were Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus faecalis, Escherichia coli and S. typhimurium. Ethanol extract （0.5 mg/mL） of Cladophora glomerata inhibited growth of all the test organisms. Primary detection of active compounds showed that maeroalgae （Cladophora glomerata） containing flavonoids, alkaloids, phenols and tannins. Gas Chromatography-Mass Spectrometry was used to know the compounds which responsible of antibacterial activity and they were g-Pentadecanone that was found to be a major compound （42.67%） followed by 8-Octadecanone （22.43%） and Salicylic acid （20.04%） in addition to 10-hexadecaden （8.01%）. These findings suggest the possibility of using the Cladophora glomerata as a novel source of natural antimicrobial agents in pharmaceutical industries.
文摘The amylase obtained from Cladophora hutchinsiae was purified by the starch affinity method(11.4-fold and specific activity of 89.7±2.6 U/mg protein)and examined for its biochemical characterization,thermodynamic properties,and use in some industrial applications.As a result of SDS-PAGE analysis,the presence of a single band of 66.2 kDa was determined.It was determined that the enzyme showed optimum activity at pH 6.00 and 10℃.In the presence of soluble starch as substrate,Km,Vmax and kcat values were calculated as 1.49±0.03 mg/mL,0.18±0.01 U and 0.003 s−1respectively.The enzyme demonstrated remarkable pH stability.Enzyme activity was investigated in a medium containing some organic solvent and cations.While amylase was inhibited by ethanol,acetonitrile,glycerol,and acetone(10%),no change in activity was observed in the presence of isopropanol.In addition,it was determined that while Cu2+and Hg2+metal ions(5 mM)effectively inhibited the amylase enzyme,Ca2+ion activates the amylase enzyme.The activation energy(Ea)was calculated as at 28.3 kJ mol^(−1).It was also found to be effective in releasing the reducing sugar from different fruit juice and fish feed.The amount of reducing sugar released as a result of incubation of fruit juices with enzyme for 3 h was observed the most in apple juice(from 1658.3±33.8μg/mL to 1945.6±36.7μg/mL)and the increase in the amount of reducing sugar was found to be 1.53 times in fish feed.According to the results obtained from the study,it can be said that the amylase obtained from seaweed can be used in different industrial areas.
