Many recent studies are concerned with low cost,easy to handle and alternative renewable energy as a feasible solution for the upcoming crisis of energy shortage.Microalgae are unicellular entities the can only depend...Many recent studies are concerned with low cost,easy to handle and alternative renewable energy as a feasible solution for the upcoming crisis of energy shortage.Microalgae are unicellular entities the can only depend on CO_(2),water and solar power to cover their nutritional needs.The current study is concerned with using algal cells in a polymeric hydrogel,as a cheap source of energy for electricity generation.Chlorella vulgaris has been proved to be a promising algal species for electricity generation,as compared with Micractinium reisseri.PVA hydrogel has been used for the immobilization of both algal species in order to protect them from the adverse surrounding conditions in addition to its ability to slowly release the required water molecules according to needs.Under these conditions,C.vulgaris showed the ability to generate 60 mV compared with 15 mV generated by M.reisseri.Scanning electron micrographs showed nano-threads that bind the C.vulgaris cells to each other,indicating the ability of algae to create nanowires that facilitate the electron transfer among algal cells and from cells to the nearest electrode.However,we would expect an increase in the produced potential with simultaneous amendment of environmentally polluted water,such as sewage or waste water.Both of FTIR and raman spectroscopy proved the presence of the characteristic groups of PVA hydrogel and proved the proper integration of the algal cells inside the hydrogel cavities.展开更多
Water contaminated with pathogenic microbes is considered as one of the most common routes for transmitting diseases in human beings.Different methods have been applied for the decontamination of microbes in contamina...Water contaminated with pathogenic microbes is considered as one of the most common routes for transmitting diseases in human beings.Different methods have been applied for the decontamination of microbes in contaminated water.In the current study,an easy to do hydrothermal method has been used for the preparation of TiO_(2)-Ag nanoparticles.The obtained material was characterised using a scanning electron microscope(SEM)and fourier transform infra-red spectroscopy(FTIR).The morphological appearance of the obtained nanoparticles was in the shape of a sphere with a size range of 60-90 nm.The antimicrobial activity of the prepared nanoparticles was tested against several pathogenic bacteria and fungi.The obtained results proved that the nanoparticles succeeded to affect all the tested microbes in the following order:Bacillus cereus ATCC6633>Pseudomonas aeruginosa ATCC9027=Klebsiella pneumoniae ATCC13883>Vibrio cholera ATCC700=Candida albicans ATCC 700=Escherichia coli NCTC10418>Staphylococcus aureus ATCC6538.The minimum inhibitory concentration(MIC)of the prepared nanoparticles varied among the tested microbes at range of 12 mg/ml and 25 mg/ml.These results encourage the application of prepared TiO_(2)-Ag nanoparticles for treatment of microbe-contaminated waters.展开更多
Current investigation has shown that human exposure to aflatoxins is not limited to the administration of contaminated cereals,but water is another possible source.This study was aimed to design easily applicable meth...Current investigation has shown that human exposure to aflatoxins is not limited to the administration of contaminated cereals,but water is another possible source.This study was aimed to design easily applicable method to eliminate aflatoxin B2(AFB2)from contaminated drinking water.Electrospinning has been used for preparation of probiotic-coated polyvinyl alcohol(PVA)and cellulose acetate(CA)nanofibers.Both of these hybrid nanofibers were studied by scanning electron microscopy(SEM)and Fourier-transformed infrared spectroscopy(FT-IR).SEM showed the proper coating of probiotic strains(Kluyveromyces lactis CBS 2359 and Saccharomyces cerevisiae ATCC 9763)on both nanofiber types.Different areas(1-5 cm^(2))of the probiotic-nanofiber hybrid were used to enhance the removal of 20 ng/ml of aflatoxin B2(AFB2)from prepared AFB2-contaminated water over time.Results revealed that a 5 cm^(2) area of probiotic-coated PVA nanofibers can eliminate 97.5% of AFB2 as compared to 87.5%,90.5%,93.5%,and 95.5%,for 1 cm2,2 cm^(2),3 cm^(2),and 4 cm^(2),respectively,while probiotic-coated CA nanofibers were slightly less effective.Nevertheless,the cytotoxicity of probiotics-CA treated water on cultured human fibroblasts was almost 10 times lower than the cytotoxicity recorded in probiotics-PVA treated water.Therefore,results of the current research suggest that probiotics-polymer nanofiber membranes can be used as an extra stage in the water purification system for the treatment of AFB2-contaminated water.展开更多
基金funding this work through General Research Project under grant number(R.G.P.1/26/38).
文摘Many recent studies are concerned with low cost,easy to handle and alternative renewable energy as a feasible solution for the upcoming crisis of energy shortage.Microalgae are unicellular entities the can only depend on CO_(2),water and solar power to cover their nutritional needs.The current study is concerned with using algal cells in a polymeric hydrogel,as a cheap source of energy for electricity generation.Chlorella vulgaris has been proved to be a promising algal species for electricity generation,as compared with Micractinium reisseri.PVA hydrogel has been used for the immobilization of both algal species in order to protect them from the adverse surrounding conditions in addition to its ability to slowly release the required water molecules according to needs.Under these conditions,C.vulgaris showed the ability to generate 60 mV compared with 15 mV generated by M.reisseri.Scanning electron micrographs showed nano-threads that bind the C.vulgaris cells to each other,indicating the ability of algae to create nanowires that facilitate the electron transfer among algal cells and from cells to the nearest electrode.However,we would expect an increase in the produced potential with simultaneous amendment of environmentally polluted water,such as sewage or waste water.Both of FTIR and raman spectroscopy proved the presence of the characteristic groups of PVA hydrogel and proved the proper integration of the algal cells inside the hydrogel cavities.
基金The authors extend their appreciation to the Deanship of Scientific Research at the King Khalid University for funding this work through the General Research Project under grant number-R.G.P.1/26/38.
文摘Water contaminated with pathogenic microbes is considered as one of the most common routes for transmitting diseases in human beings.Different methods have been applied for the decontamination of microbes in contaminated water.In the current study,an easy to do hydrothermal method has been used for the preparation of TiO_(2)-Ag nanoparticles.The obtained material was characterised using a scanning electron microscope(SEM)and fourier transform infra-red spectroscopy(FTIR).The morphological appearance of the obtained nanoparticles was in the shape of a sphere with a size range of 60-90 nm.The antimicrobial activity of the prepared nanoparticles was tested against several pathogenic bacteria and fungi.The obtained results proved that the nanoparticles succeeded to affect all the tested microbes in the following order:Bacillus cereus ATCC6633>Pseudomonas aeruginosa ATCC9027=Klebsiella pneumoniae ATCC13883>Vibrio cholera ATCC700=Candida albicans ATCC 700=Escherichia coli NCTC10418>Staphylococcus aureus ATCC6538.The minimum inhibitory concentration(MIC)of the prepared nanoparticles varied among the tested microbes at range of 12 mg/ml and 25 mg/ml.These results encourage the application of prepared TiO_(2)-Ag nanoparticles for treatment of microbe-contaminated waters.
基金the General Research Project under grant number-R.G.P.1/26/38.
文摘Current investigation has shown that human exposure to aflatoxins is not limited to the administration of contaminated cereals,but water is another possible source.This study was aimed to design easily applicable method to eliminate aflatoxin B2(AFB2)from contaminated drinking water.Electrospinning has been used for preparation of probiotic-coated polyvinyl alcohol(PVA)and cellulose acetate(CA)nanofibers.Both of these hybrid nanofibers were studied by scanning electron microscopy(SEM)and Fourier-transformed infrared spectroscopy(FT-IR).SEM showed the proper coating of probiotic strains(Kluyveromyces lactis CBS 2359 and Saccharomyces cerevisiae ATCC 9763)on both nanofiber types.Different areas(1-5 cm^(2))of the probiotic-nanofiber hybrid were used to enhance the removal of 20 ng/ml of aflatoxin B2(AFB2)from prepared AFB2-contaminated water over time.Results revealed that a 5 cm^(2) area of probiotic-coated PVA nanofibers can eliminate 97.5% of AFB2 as compared to 87.5%,90.5%,93.5%,and 95.5%,for 1 cm2,2 cm^(2),3 cm^(2),and 4 cm^(2),respectively,while probiotic-coated CA nanofibers were slightly less effective.Nevertheless,the cytotoxicity of probiotics-CA treated water on cultured human fibroblasts was almost 10 times lower than the cytotoxicity recorded in probiotics-PVA treated water.Therefore,results of the current research suggest that probiotics-polymer nanofiber membranes can be used as an extra stage in the water purification system for the treatment of AFB2-contaminated water.
