The adsorption of fast yellow dye onto dried biomass Padina pavonica was studied in batch experiments. The amount of dye adsorbed (mg/g) was increased with the increase in initial dye concentration. An equilibrium tim...The adsorption of fast yellow dye onto dried biomass Padina pavonica was studied in batch experiments. The amount of dye adsorbed (mg/g) was increased with the increase in initial dye concentration. An equilibrium time of about 90 min was achieved for dye concentrations ranging from 5 to 160 mg/L with maximum removal percentage of 73.2%. Pseudo-first and second order kinetic models have been used to analyze the adsorption data. The pseudo second-order kinetic model adequately described the adsorption data with correlation coefficient between 0.96 and 1.084. Fourier transform infra-red analysis demonstrated the chelating character of the dye molecule to different functionalities groups of the alga. Stirring speed higher than 50 rpm revealed no significant changes in dye adsorption. Temperature ranging from 15℃ to 65℃ showed stability followed by a decrease in adsorption. Scanning electron microscopy of adsorbent particles showed a high surface porosity allowing the free passage of dye molecules.展开更多
Padina pavonica is one of the common macro-algae that inhabit coastal inter-tidal zones around the world. It is one of the two brown algae known to science today that calcifies. It precipitates CaCO3 in the microscopy...Padina pavonica is one of the common macro-algae that inhabit coastal inter-tidal zones around the world. It is one of the two brown algae known to science today that calcifies. It precipitates CaCO3 in the microscopy form of Aragonite needle shape seen macroscopically as a vertical ventral stripes. Here we will summarize the information available since the beginning of the 20th century, taking into consideration the algal distribution, macro and micro-morphology, cytology, reproduction, CaCO3 bio-mineralization, and a slight reference to the commercial aspects, i.e., its use in the medical and cosmetic industries. This paper discusses the likely advantages that Padina gains by the calcification and the effect of pH caused by global climate changes on this calcification. We will describe the distribution of Padina, while focusing on the morphology of P. pavonica, as described in the literature, occasionally comparing it to another common species in Tel-Baruch—P. gymnospora. This review is somewhat prolog for the upcoming research.展开更多
Objective:To estimate the fatty acids content in the brown algae Padina pavonica(P.pavonica)and Hormophysa triquetra(H.triquetra)and evaluate their potential antimicrobial activity as bioactive compounds.Methods:The f...Objective:To estimate the fatty acids content in the brown algae Padina pavonica(P.pavonica)and Hormophysa triquetra(H.triquetra)and evaluate their potential antimicrobial activity as bioactive compounds.Methods:The fatty acid compositions of the examined species were analyzed using gas chromatography-mass spectrometry.The antimicrobial activity of crude and fatty acids was assessed using the agar plug technique.Results:The fatty acids profile ranged from C8:0 to C20:4.Concentration of saturated fatty acids in P.pavonica was in the order palmitic>myristic>stearic whereas concentration of the unsaturated fatty acids was oleic acid>palmitoleic>9-cis-hexadecenoic>linoleic acid>α-linolenic>arachidonic>elaidic acid.H.triquetra contained high concentration of saturated fatty acids than those of P.pavonica which was in the order as follows:palmitic>margaric>myristic>nonadecyclic>stearic>caprylic>tridecylic>pentadecylic>lauric while the unsaturated fatty acids consisted of oleic>nonadecenoic>non adecadienoate>margaroleic.The crude and fatty acid extracts of H.triquetra and P.pavonica were biologically active on the tested pathogens.H.triquetra exhibited a larger inhibitory zone than P.pavonica.Conclusions:The brown algae P.pavonica and H.triquetra have high efficient amount of fatty acids and showed strong antibacterial activity,especially H.triquetra.展开更多
文摘The adsorption of fast yellow dye onto dried biomass Padina pavonica was studied in batch experiments. The amount of dye adsorbed (mg/g) was increased with the increase in initial dye concentration. An equilibrium time of about 90 min was achieved for dye concentrations ranging from 5 to 160 mg/L with maximum removal percentage of 73.2%. Pseudo-first and second order kinetic models have been used to analyze the adsorption data. The pseudo second-order kinetic model adequately described the adsorption data with correlation coefficient between 0.96 and 1.084. Fourier transform infra-red analysis demonstrated the chelating character of the dye molecule to different functionalities groups of the alga. Stirring speed higher than 50 rpm revealed no significant changes in dye adsorption. Temperature ranging from 15℃ to 65℃ showed stability followed by a decrease in adsorption. Scanning electron microscopy of adsorbent particles showed a high surface porosity allowing the free passage of dye molecules.
文摘Padina pavonica is one of the common macro-algae that inhabit coastal inter-tidal zones around the world. It is one of the two brown algae known to science today that calcifies. It precipitates CaCO3 in the microscopy form of Aragonite needle shape seen macroscopically as a vertical ventral stripes. Here we will summarize the information available since the beginning of the 20th century, taking into consideration the algal distribution, macro and micro-morphology, cytology, reproduction, CaCO3 bio-mineralization, and a slight reference to the commercial aspects, i.e., its use in the medical and cosmetic industries. This paper discusses the likely advantages that Padina gains by the calcification and the effect of pH caused by global climate changes on this calcification. We will describe the distribution of Padina, while focusing on the morphology of P. pavonica, as described in the literature, occasionally comparing it to another common species in Tel-Baruch—P. gymnospora. This review is somewhat prolog for the upcoming research.
文摘Objective:To estimate the fatty acids content in the brown algae Padina pavonica(P.pavonica)and Hormophysa triquetra(H.triquetra)and evaluate their potential antimicrobial activity as bioactive compounds.Methods:The fatty acid compositions of the examined species were analyzed using gas chromatography-mass spectrometry.The antimicrobial activity of crude and fatty acids was assessed using the agar plug technique.Results:The fatty acids profile ranged from C8:0 to C20:4.Concentration of saturated fatty acids in P.pavonica was in the order palmitic>myristic>stearic whereas concentration of the unsaturated fatty acids was oleic acid>palmitoleic>9-cis-hexadecenoic>linoleic acid>α-linolenic>arachidonic>elaidic acid.H.triquetra contained high concentration of saturated fatty acids than those of P.pavonica which was in the order as follows:palmitic>margaric>myristic>nonadecyclic>stearic>caprylic>tridecylic>pentadecylic>lauric while the unsaturated fatty acids consisted of oleic>nonadecenoic>non adecadienoate>margaroleic.The crude and fatty acid extracts of H.triquetra and P.pavonica were biologically active on the tested pathogens.H.triquetra exhibited a larger inhibitory zone than P.pavonica.Conclusions:The brown algae P.pavonica and H.triquetra have high efficient amount of fatty acids and showed strong antibacterial activity,especially H.triquetra.
