This study was to investigate the structure and rat fecal microbial fermentation properties of a polysaccharide fraction(PHP2)isolated from the red marine alga Porphyra haitanensis.PHP2 was characterized as a sulfated...This study was to investigate the structure and rat fecal microbial fermentation properties of a polysaccharide fraction(PHP2)isolated from the red marine alga Porphyra haitanensis.PHP2 was characterized as a sulfated glucogalactan,with a hypothetical backbone structure of→4)Gα(1→6)G4 Sβ(1→4)Glc(1→and a side chain of Man(1→6)Glc.PHP2 had an irregular spherical chain conformation.The 16 S r RNA sequence analysis revealed that PHP2 modulated the rat fecal micro-flora composition,with a similar effect to inulin,changing the dominant genus(Lactobacillus and Escherichia-Shigella)and promoting the growth of organisms that degrade sulfur-containing polysaccharides,such as Desulfovibrio,Ruminococcaceae_UCG-005,and Ruminococcus_2.PHP2 can promote production of acetic,propionic and butyric acid by rat fecal micro-flora.Prediction of metabolic function suggested that PHP2 could modulate cholesterol metabolism.The sulfated glucogalactan fermentation behavior may be associated with its monosaccharide composition,chain branching and chain conformation.PHP2 appeared to have considerable potential as functional food,and was associated with sulfur-containing polysaccharides in general.展开更多
Porphyra polysaccharide is a special kind of nutrient showing multiple physiological functions including regulating cell proliferation,but the detailed mechanisms are not fully revealed,impairing its further developme...Porphyra polysaccharide is a special kind of nutrient showing multiple physiological functions including regulating cell proliferation,but the detailed mechanisms are not fully revealed,impairing its further development and applications.This work was to purify and characterize the Porphyra haitanensis polysaccharide(PH),investigate its physiological function,and demonstrate the underlying mechanisms.The purified PH was first characterized by Fourier-transform infrared spectroscopy.Then an intestinal epithelial cell model was established,in which PH significantly suppressed cell hyperplasia.Specifically,PH activated the Hippo/YAP pathway,which subsequently activated m TOR pathway,however m TOR activated Hippo in the absence of PH.Moreover,both the inhibition of Hippo by YAP1 knock-down and the suppression of m TOR by rapamycin impaired PH function.These results indicated that PH attenuated hyperplasia activity by remodeling the cross-talk between Hippo/YAP and m TOR pathways,which revealed potential targets and approaches for treating hyperplasia-related diseases and provided novel ways to utilize P.haitanensis as well as other related functional foods.展开更多
RAPD (Randomly Amplified Polymorphic DNA) analysis was performed with filaments of 15 Porphyra lines representing four important groups (P. yezoensis, P. haitanensis, P. katadai var. Hemiphylla and P. digospermatangia...RAPD (Randomly Amplified Polymorphic DNA) analysis was performed with filaments of 15 Porphyra lines representing four important groups (P. yezoensis, P. haitanensis, P. katadai var. Hemiphylla and P. digospermatangia). Eight stable and repeatable RAPD bands amplified with two primers, OPN-02 and OPJ-18, were selected for the construction of DNA fingerprinting. The RAPD results were scored based on the presence or absence of each of the 8 bands and then converted to computer language expressed with two digitals, 1 and 0, which represented the presence (numbered as 1) or absence (numbered as 0) of each band, respectively. Based on these results, a model DNA fingerprint and a computerized DNA fingerprint were constructed. In the constructed DNA fingerprint, each Porphyra line has its unique fingerprinting pattern and can be easily distinguished from each other. Later, a software, named as PhGI, was designed based on this DNA fingerprinting. It can be used in practical Porphyra line identification.展开更多
Isolated protoplasts from thalli of Porphyra haitanensis and Porphyra yezoensis were treated with colchicine or irradiated by ultraviolet (UV ). Several types of color variants were observed among the protoplast offsp...Isolated protoplasts from thalli of Porphyra haitanensis and Porphyra yezoensis were treated with colchicine or irradiated by ultraviolet (UV ). Several types of color variants were observed among the protoplast offspring. After treatment with colchicine: (1) 0.04-0.09% of red type variants in P. haitanensis were obtained; (2) The rate of red type variants and the variegated chimeral thalli composed of red type and wild type of sectors were 6.31- 1.11% in P. yezoensis. After irradiation with UV: (1) 3.5- 10.5% of red type variants in P. yezoensis were obtained: (2) 0.5-2-0% of red type variants and the variegated chimeral thalli composed of red type and wild type of sectors were obtained in P. haitanensis. Colchicine and UV’s mutangenic effects on P. yezoensis protoplasts were stronger than those on P. haitanensis protoplasts. The most efficient concentration of colchicine was 0.05%. The optimal length of UV-radiation was 1/2 min (radiation distance 5 cm). The red type variants induced, by colchicine展开更多
Free living conchocelis of Porphyra yezoensis Ueda (Bangiales, Rhodophyta) were treated with 6 0Co γ rays of different doses (ranging from 100 Gy to 1000 Gy) to induce mutation. Most of the conchocelis maintained the...Free living conchocelis of Porphyra yezoensis Ueda (Bangiales, Rhodophyta) were treated with 6 0Co γ rays of different doses (ranging from 100 Gy to 1000 Gy) to induce mutation. Most of the conchocelis maintained the capability of penetrating into shells, growing and forming colonies in shells, but their vitality was seriously impaired by the irradiation of γ rays. A few conchocelis pigments were mutagenized directly into different color pigment mutants whose progeny conchospores and foliose thalli had the same colors. However, some irradiated conchocelis did not show the change in color at the conchocelis stage. The pigment mutation could be observed only after the conchospores of these conchocelis had germinated into young foliose thalli. Irradiation of low dose (100 Gy) promoted the growth of thallus and many with altered morphology were observed. Conchospores of the irradiated conchocelis attached to the culture nets were cultured in the sea, and growth of these progenies was observed and measured.展开更多
Electroporation, PEG, PEG plus electroporation and Biolistics methods were tested ingene transformation of P. yezoensis. The exogenous gus was from plasmid of pBI121 and pCAMBI-A1301, both contain the CaMV35S promoter...Electroporation, PEG, PEG plus electroporation and Biolistics methods were tested ingene transformation of P. yezoensis. The exogenous gus was from plasmid of pBI121 and pCAMBI-A1301, both contain the CaMV35S promoter. The receptors included the prooplasts, tissues and free-liv-ing conchocelis filaments of P. yezoensis. Several factors, for example, the voltage, capacitance and bi-valent cations, etc., were studied. Results show that these four methods are all efficient for gene transfor-mation in P. yezoensis; and that PEG is the best one, with transformation efficiency of up to 4 ×10-5.GUS activity was detected 26 days after transfation by using PEG method.展开更多
基金supported by the Scientific Research Foundation of Graduate School of Fujian Agriculture and Forestry University(1122yb065)the Program for Leading Talent in Fujian Provincial University(660160190)。
文摘This study was to investigate the structure and rat fecal microbial fermentation properties of a polysaccharide fraction(PHP2)isolated from the red marine alga Porphyra haitanensis.PHP2 was characterized as a sulfated glucogalactan,with a hypothetical backbone structure of→4)Gα(1→6)G4 Sβ(1→4)Glc(1→and a side chain of Man(1→6)Glc.PHP2 had an irregular spherical chain conformation.The 16 S r RNA sequence analysis revealed that PHP2 modulated the rat fecal micro-flora composition,with a similar effect to inulin,changing the dominant genus(Lactobacillus and Escherichia-Shigella)and promoting the growth of organisms that degrade sulfur-containing polysaccharides,such as Desulfovibrio,Ruminococcaceae_UCG-005,and Ruminococcus_2.PHP2 can promote production of acetic,propionic and butyric acid by rat fecal micro-flora.Prediction of metabolic function suggested that PHP2 could modulate cholesterol metabolism.The sulfated glucogalactan fermentation behavior may be associated with its monosaccharide composition,chain branching and chain conformation.PHP2 appeared to have considerable potential as functional food,and was associated with sulfur-containing polysaccharides in general.
基金supported by the National Key R&D Program of China(2017YFD0400203)the National Natural Science Foundation of China(31801452)+3 种基金the Zhejiang Provincial Science and Technology Foundation of China(2018C02025 and 2019C02069)the Zhejiang Provincial Natural Science Foundation of China(LGN21C200013)the China Postdoctoral Science Foundation(2019M662108)the Scientific Research Fund of Zhejiang Provincial Education Department(Y201942404)。
文摘Porphyra polysaccharide is a special kind of nutrient showing multiple physiological functions including regulating cell proliferation,but the detailed mechanisms are not fully revealed,impairing its further development and applications.This work was to purify and characterize the Porphyra haitanensis polysaccharide(PH),investigate its physiological function,and demonstrate the underlying mechanisms.The purified PH was first characterized by Fourier-transform infrared spectroscopy.Then an intestinal epithelial cell model was established,in which PH significantly suppressed cell hyperplasia.Specifically,PH activated the Hippo/YAP pathway,which subsequently activated m TOR pathway,however m TOR activated Hippo in the absence of PH.Moreover,both the inhibition of Hippo by YAP1 knock-down and the suppression of m TOR by rapamycin impaired PH function.These results indicated that PH attenuated hyperplasia activity by remodeling the cross-talk between Hippo/YAP and m TOR pathways,which revealed potential targets and approaches for treating hyperplasia-related diseases and provided novel ways to utilize P.haitanensis as well as other related functional foods.
基金This study was supported by China Ocean "863" ProjectNational Natural Science Foundation of China.
文摘RAPD (Randomly Amplified Polymorphic DNA) analysis was performed with filaments of 15 Porphyra lines representing four important groups (P. yezoensis, P. haitanensis, P. katadai var. Hemiphylla and P. digospermatangia). Eight stable and repeatable RAPD bands amplified with two primers, OPN-02 and OPJ-18, were selected for the construction of DNA fingerprinting. The RAPD results were scored based on the presence or absence of each of the 8 bands and then converted to computer language expressed with two digitals, 1 and 0, which represented the presence (numbered as 1) or absence (numbered as 0) of each band, respectively. Based on these results, a model DNA fingerprint and a computerized DNA fingerprint were constructed. In the constructed DNA fingerprint, each Porphyra line has its unique fingerprinting pattern and can be easily distinguished from each other. Later, a software, named as PhGI, was designed based on this DNA fingerprinting. It can be used in practical Porphyra line identification.
文摘Isolated protoplasts from thalli of Porphyra haitanensis and Porphyra yezoensis were treated with colchicine or irradiated by ultraviolet (UV ). Several types of color variants were observed among the protoplast offspring. After treatment with colchicine: (1) 0.04-0.09% of red type variants in P. haitanensis were obtained; (2) The rate of red type variants and the variegated chimeral thalli composed of red type and wild type of sectors were 6.31- 1.11% in P. yezoensis. After irradiation with UV: (1) 3.5- 10.5% of red type variants in P. yezoensis were obtained: (2) 0.5-2-0% of red type variants and the variegated chimeral thalli composed of red type and wild type of sectors were obtained in P. haitanensis. Colchicine and UV’s mutangenic effects on P. yezoensis protoplasts were stronger than those on P. haitanensis protoplasts. The most efficient concentration of colchicine was 0.05%. The optimal length of UV-radiation was 1/2 min (radiation distance 5 cm). The red type variants induced, by colchicine
文摘Free living conchocelis of Porphyra yezoensis Ueda (Bangiales, Rhodophyta) were treated with 6 0Co γ rays of different doses (ranging from 100 Gy to 1000 Gy) to induce mutation. Most of the conchocelis maintained the capability of penetrating into shells, growing and forming colonies in shells, but their vitality was seriously impaired by the irradiation of γ rays. A few conchocelis pigments were mutagenized directly into different color pigment mutants whose progeny conchospores and foliose thalli had the same colors. However, some irradiated conchocelis did not show the change in color at the conchocelis stage. The pigment mutation could be observed only after the conchospores of these conchocelis had germinated into young foliose thalli. Irradiation of low dose (100 Gy) promoted the growth of thallus and many with altered morphology were observed. Conchospores of the irradiated conchocelis attached to the culture nets were cultured in the sea, and growth of these progenies was observed and measured.
文摘Electroporation, PEG, PEG plus electroporation and Biolistics methods were tested ingene transformation of P. yezoensis. The exogenous gus was from plasmid of pBI121 and pCAMBI-A1301, both contain the CaMV35S promoter. The receptors included the prooplasts, tissues and free-liv-ing conchocelis filaments of P. yezoensis. Several factors, for example, the voltage, capacitance and bi-valent cations, etc., were studied. Results show that these four methods are all efficient for gene transfor-mation in P. yezoensis; and that PEG is the best one, with transformation efficiency of up to 4 ×10-5.GUS activity was detected 26 days after transfation by using PEG method.
