Colorectal cancer(CRC)is a common digestive tract tumor worldwide.Specific microorganisms,including Fusobacterium nucleatum(F.nucleatum)and Escherichia coli(E.coli),are abundant in colonic mucosa and can promote the c...Colorectal cancer(CRC)is a common digestive tract tumor worldwide.Specific microorganisms,including Fusobacterium nucleatum(F.nucleatum)and Escherichia coli(E.coli),are abundant in colonic mucosa and can promote the cancer progression and malignancy.Therefore,a therapeutic strategy is proposed to deliver effective drugs to colorectum for both anticancer and antibacteria.Here we used thin-film dispersionmethod to encapsulate hemiprotonic phenanthroline-phenanthroline^(+)(ph-ph^(+))into nanomicelle.The results showed that the drug-loading nanomicelle had good dispersion,and the particle size was about 28 nm.In vitro assay indicated that the nanomicelle was active against CRC-related obligate and facultative anaerobes.In human CRC cells,the nanomicelle could effectively inhibit cell proliferation and induce apoptosis.In vivo distribution showed that the nanomicelle could release ph-ph^(+) mainly in the colorectum.In CRC model mice,the nanomicelle significantly reduced tumor number and volume,and decreased the bacteria load and colorectal inflammation.Together,the study identifies that the ph-ph^(+) nanomicelle has the potential to apply in treating CRC,and also suggests that anticancer combined with antimicrobial therapy would be a feasible way for CRC therapy.展开更多
Endophytic actinomycetes are considered as one of the relatively unexplored potential sources in search of antibiotic producer against antibiotic resistant pathogens. A potent strain isolated from Catharanthus roseus ...Endophytic actinomycetes are considered as one of the relatively unexplored potential sources in search of antibiotic producer against antibiotic resistant pathogens. A potent strain isolated from Catharanthus roseus that displays antibacterial potential against antibiotic resistant human pathogen Staphylococcus aureus was characterized and designated as Micrococcus yunnanensis strain rsk5. Rsk5 is capable of producing optimum antibacterial metabolites on starch casein medium at 30 °C, p H 5 and 2% Na Cl condition. The crude antibacterial agent was extracted from fermentation broth by ethyl acetate and separated by TLC using chloroform-methanol(24:1, v/v) solvent system with R f value of 0.26. It was partially purified by flash chromatography, followed by HPLC and analyzed by ultraviolet visible spectrophotometer to get absorption maxima at 208.4 nm. The ESI-MS spectra showed molecular ion peaks at m/z 472.4 [M-H], which does not match with any known antibacterial compound.展开更多
Aluminum specimens were anodized in a sulfuric acid bath, then silver was electrodeposited in poresof the anodized aluminum by using alternating current . The anodized aluminum with deposited silver was testedfor its ...Aluminum specimens were anodized in a sulfuric acid bath, then silver was electrodeposited in poresof the anodized aluminum by using alternating current . The anodized aluminum with deposited silver was testedfor its antibacterial performance. The results show that the antibacterial rates of the specimens are above 95%against the growth of E. coli, P. aeruginasa, S. faecalis and S. aureus. The morphology of the silver in pores ofanodized aluminum is characterized by transmission electron microscopy, and the micrographs indicate that silveris assembled in the form of nanowires with a diameter of 10 nm or 25 nm. The nanowires have a structure of parallelbright stripes alternating with parallel dark stripes.展开更多
With natural polyphenol compound tannic acid(TA)as the ingredient,copper tannate(CuTA)nanolayer material was formed by self-assembly under the conditions of heating and copper ion.Copper ion and tannic acid could coor...With natural polyphenol compound tannic acid(TA)as the ingredient,copper tannate(CuTA)nanolayer material was formed by self-assembly under the conditions of heating and copper ion.Copper ion and tannic acid could coordinate to form Cu-O-C structure which was similar to the Fe-N-C structure of natural heme enzymes.In addition,the obtained CuTA nanomaterial possessed excellent peroxidase-like catalytic activity and stability.Based on this excellent enzymatic activity,CuTA nanomaterials could be used for colorimetric detection of hydrogen peroxide with a smartphone and decomposition of organic dyes.Based on the structural characteristics and catalytic activity,the copper tannate nanozymes could also serve as potential antibacterial reagents to effectively inhibit the growth of gram-negative and positive bacteria in a low hydrogen peroxide level.This work may promote the exploration of novel peroxidase mimetics and broaden the applications of nanozymes.展开更多
The antibacterial capability of silver loaded hydroxyapatite(HA\|Ag) in both poor nutrient phosphate buffer saline solution(PBS,pH=7.4)and nutrient rich medium,which represented two kinds of typical conditions in real...The antibacterial capability of silver loaded hydroxyapatite(HA\|Ag) in both poor nutrient phosphate buffer saline solution(PBS,pH=7.4)and nutrient rich medium,which represented two kinds of typical conditions in real life,was evaluated respectively using Escherichia coli as a model.At 0 4?mg/mL in PBS solution containing an initial cell concentration of 10\+6/mL,HA\|Ag killed all the E.coli cells in the PBS solution within 4 5?h .In a nutrient rich medium containing a cell concentration of 10\+7/mL,HA\|Ag exhibited a remarkable inhibitory effect of E.coli cells.The maximum specific growth rate in the medium containing 3?mg/mL HA\|Ag was only 0 292, 26% of that in a control sample which was 1 116,and the viable cell concentration in the former HA\|Ag medium was just 40% of that in the control.As a safe antibacterial agent,HA\|Ag powder demonstrated antibacterial efforts both in poor nutrient and in nutrient rich environment.It seems that the HA\|Ag compound hold a lot of promises for practical applications.展开更多
基金supported by National Natural Science Foundation of China(No.82073830)Chongqing Natural Science Foundation(No.CSTB2022NSCQ-MSX1328).
文摘Colorectal cancer(CRC)is a common digestive tract tumor worldwide.Specific microorganisms,including Fusobacterium nucleatum(F.nucleatum)and Escherichia coli(E.coli),are abundant in colonic mucosa and can promote the cancer progression and malignancy.Therefore,a therapeutic strategy is proposed to deliver effective drugs to colorectum for both anticancer and antibacteria.Here we used thin-film dispersionmethod to encapsulate hemiprotonic phenanthroline-phenanthroline^(+)(ph-ph^(+))into nanomicelle.The results showed that the drug-loading nanomicelle had good dispersion,and the particle size was about 28 nm.In vitro assay indicated that the nanomicelle was active against CRC-related obligate and facultative anaerobes.In human CRC cells,the nanomicelle could effectively inhibit cell proliferation and induce apoptosis.In vivo distribution showed that the nanomicelle could release ph-ph^(+) mainly in the colorectum.In CRC model mice,the nanomicelle significantly reduced tumor number and volume,and decreased the bacteria load and colorectal inflammation.Together,the study identifies that the ph-ph^(+) nanomicelle has the potential to apply in treating CRC,and also suggests that anticancer combined with antimicrobial therapy would be a feasible way for CRC therapy.
基金supported by United Grant Commission, Pune, India (Grant no. 47-1328/10) for financial support
文摘Endophytic actinomycetes are considered as one of the relatively unexplored potential sources in search of antibiotic producer against antibiotic resistant pathogens. A potent strain isolated from Catharanthus roseus that displays antibacterial potential against antibiotic resistant human pathogen Staphylococcus aureus was characterized and designated as Micrococcus yunnanensis strain rsk5. Rsk5 is capable of producing optimum antibacterial metabolites on starch casein medium at 30 °C, p H 5 and 2% Na Cl condition. The crude antibacterial agent was extracted from fermentation broth by ethyl acetate and separated by TLC using chloroform-methanol(24:1, v/v) solvent system with R f value of 0.26. It was partially purified by flash chromatography, followed by HPLC and analyzed by ultraviolet visible spectrophotometer to get absorption maxima at 208.4 nm. The ESI-MS spectra showed molecular ion peaks at m/z 472.4 [M-H], which does not match with any known antibacterial compound.
文摘Aluminum specimens were anodized in a sulfuric acid bath, then silver was electrodeposited in poresof the anodized aluminum by using alternating current . The anodized aluminum with deposited silver was testedfor its antibacterial performance. The results show that the antibacterial rates of the specimens are above 95%against the growth of E. coli, P. aeruginasa, S. faecalis and S. aureus. The morphology of the silver in pores ofanodized aluminum is characterized by transmission electron microscopy, and the micrographs indicate that silveris assembled in the form of nanowires with a diameter of 10 nm or 25 nm. The nanowires have a structure of parallelbright stripes alternating with parallel dark stripes.
基金Financial support was provided by the Natural Science Foundation of jiangsu(grant No.BK20200764)the Key Technologies R&D Program of Henan(grant No.212102310231).
文摘With natural polyphenol compound tannic acid(TA)as the ingredient,copper tannate(CuTA)nanolayer material was formed by self-assembly under the conditions of heating and copper ion.Copper ion and tannic acid could coordinate to form Cu-O-C structure which was similar to the Fe-N-C structure of natural heme enzymes.In addition,the obtained CuTA nanomaterial possessed excellent peroxidase-like catalytic activity and stability.Based on this excellent enzymatic activity,CuTA nanomaterials could be used for colorimetric detection of hydrogen peroxide with a smartphone and decomposition of organic dyes.Based on the structural characteristics and catalytic activity,the copper tannate nanozymes could also serve as potential antibacterial reagents to effectively inhibit the growth of gram-negative and positive bacteria in a low hydrogen peroxide level.This work may promote the exploration of novel peroxidase mimetics and broaden the applications of nanozymes.
文摘The antibacterial capability of silver loaded hydroxyapatite(HA\|Ag) in both poor nutrient phosphate buffer saline solution(PBS,pH=7.4)and nutrient rich medium,which represented two kinds of typical conditions in real life,was evaluated respectively using Escherichia coli as a model.At 0 4?mg/mL in PBS solution containing an initial cell concentration of 10\+6/mL,HA\|Ag killed all the E.coli cells in the PBS solution within 4 5?h .In a nutrient rich medium containing a cell concentration of 10\+7/mL,HA\|Ag exhibited a remarkable inhibitory effect of E.coli cells.The maximum specific growth rate in the medium containing 3?mg/mL HA\|Ag was only 0 292, 26% of that in a control sample which was 1 116,and the viable cell concentration in the former HA\|Ag medium was just 40% of that in the control.As a safe antibacterial agent,HA\|Ag powder demonstrated antibacterial efforts both in poor nutrient and in nutrient rich environment.It seems that the HA\|Ag compound hold a lot of promises for practical applications.
