Nanoparticle synthesis, such as green synthesis of silver nanoparticles (AgNPs) using biogenic ex... more Nanoparticle synthesis, such as green synthesis of silver nanoparticles (AgNPs) using biogenic extracts, is affected by light, which changes the characteristics of particles. However, the effect of light-emitting diodes (LEDs) on AgNP biosynthesis using fungal pigment has not been examined. In this study, LEDs of different wavelengths were used in conjunction with Talaromyces purpurogenus extracellular pigment for AgNP biosynthesis. AgNPs were synthesized by mixing 10 mL of fungal pigment with AgNO3, followed by 24 h exposure to LEDs of different wavelengths, such as blue, green, orange, red, and infrared. All treatments increased the yield of AgNPs. The solutions exposed to blue, green, and infrared LEDs exhibited a significant increase in AgNP synthesis. All AgNPs were then synthesized to determine the optimum precursor (AgNO3) concentration and reaction rate. The results indicated 5 mM AgNO3 as the optimum precursor concentration; furthermore, AgNPs-blue LED had the highest react...
ABSTRACT The extracellular pigment produced by Talaromyces purpurogenus was used as a reducing ag... more ABSTRACT The extracellular pigment produced by Talaromyces purpurogenus was used as a reducing agent in the production of silver nanoparticles (AgNPs), and the effect of physicochemical parameters (pH and light) on the synthesis were examined. To evaluate the effect of pigment constituents on AgNP synthesis, fractions were obtained by thin layer chromatography. Ultraviolet–visible spectroscopy, transmission electron microscopy, dynamic light scattering (DLS), and Fourier transform infrared spectroscopy were used to characterize the biofabricated AgNPs. The synthesis of AgNPs was enhanced under alkaline conditions, emphasizing the role of sodium hydroxide (NaOH) as an accelerator, and the effect of light on yield could be clearly perceived up to pH 10. As the pH value was increased further, the light dependency of the reaction decreased, although the DLS data suggested variation in the size of AgNPs obtained in the presence and absence of light. The AgNPs produced at optimum pH in the presence of light were nearly spherical with a size distribution of 5–40 nm. The AgNP production process was pH-dependent and light-mediated, indicating that AgNPs with different properties could be generated by controlling these physicochemical factors. GRAPHICAL ABSTRACT
Hyperphosphatemia is a secondary disorder of chronic kidney disease that causes vascular calcific... more Hyperphosphatemia is a secondary disorder of chronic kidney disease that causes vascular calcifications and bone-mineral disorders. As per the US Centers for Disease Control and Prevention, renal damage requires first-priority medical attention for patients with COVID-19; according to a Johns Hopkins Medicine report, SARS-CoV-2 can cause renal damage. Therefore, addressing the research inputs required to manage hyperphosphatemia is currently in great demand. This review highlights research inputs, such as defects in the diagnosis of hyperphosphatemia, flaws in understanding the mechanisms associated with understudied tertiary toxicities, less cited adverse effects of phosphate binders that question their use in the market, socioeconomic challenges of renal treatment and public awareness regarding the management of a phosphate-controlled diet, novel biological approaches (synbiotics) to prevent hyperphosphatemia as safer strategies with potential additional health benefits, and futur...
A method for screening lectin-producing microorganisms was developed. The presence of lectin on m... more A method for screening lectin-producing microorganisms was developed. The presence of lectin on microbial cell surfaces was used as an index for their selective isolation. The lectin-producing microorganisms adhered to sugar-modified agarose beads and were selectively eluted with specific saccharide solutions. Spin columns were an effective tool for excluding non-lectin producers. Eighty-seven percent of the microorganisms that were eluted from the beads showed hemagglutination. The results of sequence analysis indicated that some of the eluted microorganisms have not been previously identified as lectin-producing microorganisms.
When various autoclaved microbial cells suspensions (exogenous elicitors) were added to Catharant... more When various autoclaved microbial cells suspensions (exogenous elicitors) were added to Catharanthus roseus cell cultures, its growth was inhibited but 5'-phosphodiesterase (PDase) production was stimulated. The greatest effect was with autoclaved Alteromonas macleodii: the dry cell concentration decreased from 13 to 10.9 mg/ml while PDase production increased from 0.022 to 0.235 U/ml. A combination of A. macleodii (as exogenous elicitor) and 0.1%(w/v) alginate oligomers (AO: acting as both endogenous elicitor and scavenger of active oxygen species) minimized the cell growth inhibition but enhanced PDase production (0.474 U/ml) about 20 times higher than the control (no addition). The method for the preparation of mixed alginate elicitors with high activities containing exogenous elicitor (autoclaved A. macleodii), endogenous elicitor (AO), and trans-4,5-dihydroxy-2-cyclopenten-1-one was developed. The mixed alginate elicitors significantly promoted PDase production (2.67 U/ml) by C. roseus, and the productivity was increased 120-fold compared to the control without cell growth inhibition.
To characterize de-differentiated plant cultured cells and to determine factor(s) that regulate t... more To characterize de-differentiated plant cultured cells and to determine factor(s) that regulate the de-differentiated state, comparative analyses of the gene expression profiles of intact plants and three different cultured cell lines of Arabidopsis were performed by DNA microarray and RNA blot analyses. The three different cultured cell lines (T87 and two cell lines newly induced from leaf and root tissue, respectively) were used. Twenty-seven to 140 genes were down-regulated but only 9-27 genes were up-regulated in each cultured cell lines when compared to the intact plants. Genes commonly regulated in each cultured cell lines were investigated and six genes, including those related to metabolism, were found to be down-regulated and two genes, that include those related to a transcription factor, were up-regulated.
Nanoparticle synthesis, such as green synthesis of silver nanoparticles (AgNPs) using biogenic ex... more Nanoparticle synthesis, such as green synthesis of silver nanoparticles (AgNPs) using biogenic extracts, is affected by light, which changes the characteristics of particles. However, the effect of light-emitting diodes (LEDs) on AgNP biosynthesis using fungal pigment has not been examined. In this study, LEDs of different wavelengths were used in conjunction with Talaromyces purpurogenus extracellular pigment for AgNP biosynthesis. AgNPs were synthesized by mixing 10 mL of fungal pigment with AgNO3, followed by 24 h exposure to LEDs of different wavelengths, such as blue, green, orange, red, and infrared. All treatments increased the yield of AgNPs. The solutions exposed to blue, green, and infrared LEDs exhibited a significant increase in AgNP synthesis. All AgNPs were then synthesized to determine the optimum precursor (AgNO3) concentration and reaction rate. The results indicated 5 mM AgNO3 as the optimum precursor concentration; furthermore, AgNPs-blue LED had the highest react...
ABSTRACT The extracellular pigment produced by Talaromyces purpurogenus was used as a reducing ag... more ABSTRACT The extracellular pigment produced by Talaromyces purpurogenus was used as a reducing agent in the production of silver nanoparticles (AgNPs), and the effect of physicochemical parameters (pH and light) on the synthesis were examined. To evaluate the effect of pigment constituents on AgNP synthesis, fractions were obtained by thin layer chromatography. Ultraviolet–visible spectroscopy, transmission electron microscopy, dynamic light scattering (DLS), and Fourier transform infrared spectroscopy were used to characterize the biofabricated AgNPs. The synthesis of AgNPs was enhanced under alkaline conditions, emphasizing the role of sodium hydroxide (NaOH) as an accelerator, and the effect of light on yield could be clearly perceived up to pH 10. As the pH value was increased further, the light dependency of the reaction decreased, although the DLS data suggested variation in the size of AgNPs obtained in the presence and absence of light. The AgNPs produced at optimum pH in the presence of light were nearly spherical with a size distribution of 5–40 nm. The AgNP production process was pH-dependent and light-mediated, indicating that AgNPs with different properties could be generated by controlling these physicochemical factors. GRAPHICAL ABSTRACT
Hyperphosphatemia is a secondary disorder of chronic kidney disease that causes vascular calcific... more Hyperphosphatemia is a secondary disorder of chronic kidney disease that causes vascular calcifications and bone-mineral disorders. As per the US Centers for Disease Control and Prevention, renal damage requires first-priority medical attention for patients with COVID-19; according to a Johns Hopkins Medicine report, SARS-CoV-2 can cause renal damage. Therefore, addressing the research inputs required to manage hyperphosphatemia is currently in great demand. This review highlights research inputs, such as defects in the diagnosis of hyperphosphatemia, flaws in understanding the mechanisms associated with understudied tertiary toxicities, less cited adverse effects of phosphate binders that question their use in the market, socioeconomic challenges of renal treatment and public awareness regarding the management of a phosphate-controlled diet, novel biological approaches (synbiotics) to prevent hyperphosphatemia as safer strategies with potential additional health benefits, and futur...
A method for screening lectin-producing microorganisms was developed. The presence of lectin on m... more A method for screening lectin-producing microorganisms was developed. The presence of lectin on microbial cell surfaces was used as an index for their selective isolation. The lectin-producing microorganisms adhered to sugar-modified agarose beads and were selectively eluted with specific saccharide solutions. Spin columns were an effective tool for excluding non-lectin producers. Eighty-seven percent of the microorganisms that were eluted from the beads showed hemagglutination. The results of sequence analysis indicated that some of the eluted microorganisms have not been previously identified as lectin-producing microorganisms.
When various autoclaved microbial cells suspensions (exogenous elicitors) were added to Catharant... more When various autoclaved microbial cells suspensions (exogenous elicitors) were added to Catharanthus roseus cell cultures, its growth was inhibited but 5'-phosphodiesterase (PDase) production was stimulated. The greatest effect was with autoclaved Alteromonas macleodii: the dry cell concentration decreased from 13 to 10.9 mg/ml while PDase production increased from 0.022 to 0.235 U/ml. A combination of A. macleodii (as exogenous elicitor) and 0.1%(w/v) alginate oligomers (AO: acting as both endogenous elicitor and scavenger of active oxygen species) minimized the cell growth inhibition but enhanced PDase production (0.474 U/ml) about 20 times higher than the control (no addition). The method for the preparation of mixed alginate elicitors with high activities containing exogenous elicitor (autoclaved A. macleodii), endogenous elicitor (AO), and trans-4,5-dihydroxy-2-cyclopenten-1-one was developed. The mixed alginate elicitors significantly promoted PDase production (2.67 U/ml) by C. roseus, and the productivity was increased 120-fold compared to the control without cell growth inhibition.
To characterize de-differentiated plant cultured cells and to determine factor(s) that regulate t... more To characterize de-differentiated plant cultured cells and to determine factor(s) that regulate the de-differentiated state, comparative analyses of the gene expression profiles of intact plants and three different cultured cell lines of Arabidopsis were performed by DNA microarray and RNA blot analyses. The three different cultured cell lines (T87 and two cell lines newly induced from leaf and root tissue, respectively) were used. Twenty-seven to 140 genes were down-regulated but only 9-27 genes were up-regulated in each cultured cell lines when compared to the intact plants. Genes commonly regulated in each cultured cell lines were investigated and six genes, including those related to metabolism, were found to be down-regulated and two genes, that include those related to a transcription factor, were up-regulated.
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