There is an increasing interest in developing nanoparticles with diverse biologic activities.To this end,we prepared 10 to 15 nm silver nanoparticles(AgNP)from native isolates of Trichoderma atroviride.Within this stu...There is an increasing interest in developing nanoparticles with diverse biologic activities.To this end,we prepared 10 to 15 nm silver nanoparticles(AgNP)from native isolates of Trichoderma atroviride.Within this study,endophytic fungi hosted four medicinal plants in Saint Katherine Protectorate,South Sinai,Egypt have been isolated by surface sterilization technique on four isolation media.Ten species,based on their frequency of occurrence,out of twenty recovered taxa were tested for their capability to synthesize extracellular AgNPs.Trichoderma atroviride hosted Chiliadenus montanus was found to be the best candidate for the production of mycogenic AgNPs among all examined species.The mycosynthesized AgNPs were compared with chemically synthesized and characterized using Ultraviolet-visible(UV-vis)spectroscopy,Raman spectroscopy,X-ray diffraction(XRD)and high-resolution transmission electron microscopy(HRTEM)techniques.The HRTEM result showed the distribution of spherical AgNPs ranging from 10 to 15 nm.Trichoderma atroviride isolate was subjected to sequencing for confirmation of phenotypic identification.The internal transcribed spacer(ITS)1-5.8 s-ITS2 rDNA sequences obtained were compared with those deposited in the GenBank Database and registered with accession number MH283876 in the NCBI Database.Antibacterial,anticandidal and antifungal effects of chemically and mycosynthesized AgNPs were examined at various concentrations in vitro against six pathogenic bacteria and 4 pathogenic fungi by agar well diffusion technique.Standard antibiotics;Gentamicin,Amoxicillin,Clotrimazole,and Nystatin at 5μg/disk were taken as positive controls,while 5%DMSO was used as the negative control.Our data revealed that the application of mycogenic AgNPs at a concentration of 100 ppm resulted in maximum inhibition of pathogenic bacteria and fungi.These data suggest that AgNPs from native isolates of Trichoderma atroviride(MH283876)offer a source of rapid synthesis of eco-friendly,economical biomaterials that show antimicrobial activities.展开更多
Mycogen公司宣布,其Agrigenetics植物科学子公司开发出抗玉米蠕虫Diabrotica spp.(玉米生产中的主要害虫)的玉米植株。 Mycogen的总裁兼CEO Jerry Caulder指出:公司已对将天然玉米植物中的抗根蠕虫遗传物质导入其优质商商化杂种的方法...Mycogen公司宣布,其Agrigenetics植物科学子公司开发出抗玉米蠕虫Diabrotica spp.(玉米生产中的主要害虫)的玉米植株。 Mycogen的总裁兼CEO Jerry Caulder指出:公司已对将天然玉米植物中的抗根蠕虫遗传物质导入其优质商商化杂种的方法克发明申请专利保护。他预测种植对玉米根蠕虫具有天然抗性的种子将在4～5年内实现商品化。展开更多
Fungi possess remarkable capabilities for metal speciation,dissolution,and mineral formation,which contribute to the production of mycogenic nanostructures.This study explores a green chemistry approach for synthesizi...Fungi possess remarkable capabilities for metal speciation,dissolution,and mineral formation,which contribute to the production of mycogenic nanostructures.This study explores a green chemistry approach for synthesizing silver oxide-doped titanium oxide(Ag_(2)O-doped TiO_(2))bionanocomposite utilizing Trichoderma virens.The light yellowish fungal filtrate transformed into a dark brownish colloidal suspension after reacting with silver nitrate and rutile titanium(IV)oxide.X-ray diffractometry(XRD)unveiled the crystalline structure of the bio-nanocomposite(22.15 nm),showing the coexistence of cubic and rutile tetragonal phases of Ag_(2)O and TiO_(2),respectively.Fourier-transform infrared spectroscopy(FTIR)showed the presence of functional groups of alco-hols,phenols,nitro compounds,and aromatic amines derived from the cultural filtrate of T.virens.Raman analysis revealed vibrational modes corresponding to Ag_(2)O and TiO_(2) nanoparticles.Distinct sharp emission peaks characteristic to Ti,Ag,and O were depicted using energy dispersive X-ray(EDX)analysis.X-ray photo-electron spectroscopy(XPS)confirmed the presence of elemental valence states and binding energies of Ag,Ti,and O in the mycogenic nanocomposite.Field emission scanning electron microscopy(FESEM)revealed ag-gregation of polydispersed Ag_(2)O-doped TiO_(2) bionanocomposite,displaying spherical-and cuboctahedron-shaped nanostructures with rough surfaces.High-resolution transmission electron microscopy(HRTEM)showed the presence of circular-,semi-spherical-,hexagonal-,and polygonal-shaped monodispersed Ag_(2)O NPs,with defined boundaries.The Ag_(2)O NPs were obviously deposited on the sheet-like TiO_(2) NPs.Selected area electron diffraction pattern implied the polycrystallinity of the as-synthesized bionanocomposite.A broad antibacterial spectrum of the prepared bionanocomposite was attained against foodborne pathogenic bacteria;Escherichia coli(12.05 mm),Salmonella enterica(11.26 mm),and Staphylococcus aureus(11.44 mm)and phytopathogenic bac-teria;Clavibacter michiganensis subsp.michiganensis(15.72 mm),C.michiganensis subsp.capsici(10.80 mm),streptomycin-sensitive and-resistant Xanthomonas citri pv.citri(14.11 and 14.53 mm,respectively),and streptomycin-sensitive and-resistant Pectobacterium carotovorum subsp.carotovorum(11.36 and 11.07 mm,respectively)using in vitro Kirby-Bauer method.Minimum inhibitory and minimum bactericidal concentrations were determined via a broth micro-dilution assay.FESEM revealed significant morphological alterations in bacterial cells upon treatment with the bionanocomposite,including deformed shape,rough surface,cell thin-ning,wrinkled cell wall,protrusions,cavitations,and cracks.These findings signify the successful mycosynthesis of Ag_(2)O-doped TiO_(2) bionanocomposite,which acted a potent antibacterial agent against a variety of foodborne and phytopathogenic bacteria,which could be employed in environmental,biomedical,agricultural,and food bio-processing applications.展开更多
文摘There is an increasing interest in developing nanoparticles with diverse biologic activities.To this end,we prepared 10 to 15 nm silver nanoparticles(AgNP)from native isolates of Trichoderma atroviride.Within this study,endophytic fungi hosted four medicinal plants in Saint Katherine Protectorate,South Sinai,Egypt have been isolated by surface sterilization technique on four isolation media.Ten species,based on their frequency of occurrence,out of twenty recovered taxa were tested for their capability to synthesize extracellular AgNPs.Trichoderma atroviride hosted Chiliadenus montanus was found to be the best candidate for the production of mycogenic AgNPs among all examined species.The mycosynthesized AgNPs were compared with chemically synthesized and characterized using Ultraviolet-visible(UV-vis)spectroscopy,Raman spectroscopy,X-ray diffraction(XRD)and high-resolution transmission electron microscopy(HRTEM)techniques.The HRTEM result showed the distribution of spherical AgNPs ranging from 10 to 15 nm.Trichoderma atroviride isolate was subjected to sequencing for confirmation of phenotypic identification.The internal transcribed spacer(ITS)1-5.8 s-ITS2 rDNA sequences obtained were compared with those deposited in the GenBank Database and registered with accession number MH283876 in the NCBI Database.Antibacterial,anticandidal and antifungal effects of chemically and mycosynthesized AgNPs were examined at various concentrations in vitro against six pathogenic bacteria and 4 pathogenic fungi by agar well diffusion technique.Standard antibiotics;Gentamicin,Amoxicillin,Clotrimazole,and Nystatin at 5μg/disk were taken as positive controls,while 5%DMSO was used as the negative control.Our data revealed that the application of mycogenic AgNPs at a concentration of 100 ppm resulted in maximum inhibition of pathogenic bacteria and fungi.These data suggest that AgNPs from native isolates of Trichoderma atroviride(MH283876)offer a source of rapid synthesis of eco-friendly,economical biomaterials that show antimicrobial activities.
文摘Mycogen公司宣布,其Agrigenetics植物科学子公司开发出抗玉米蠕虫Diabrotica spp.(玉米生产中的主要害虫)的玉米植株。 Mycogen的总裁兼CEO Jerry Caulder指出:公司已对将天然玉米植物中的抗根蠕虫遗传物质导入其优质商商化杂种的方法克发明申请专利保护。他预测种植对玉米根蠕虫具有天然抗性的种子将在4～5年内实现商品化。
基金supported by the 2024 Yeungnam University Research Grant.
文摘Fungi possess remarkable capabilities for metal speciation,dissolution,and mineral formation,which contribute to the production of mycogenic nanostructures.This study explores a green chemistry approach for synthesizing silver oxide-doped titanium oxide(Ag_(2)O-doped TiO_(2))bionanocomposite utilizing Trichoderma virens.The light yellowish fungal filtrate transformed into a dark brownish colloidal suspension after reacting with silver nitrate and rutile titanium(IV)oxide.X-ray diffractometry(XRD)unveiled the crystalline structure of the bio-nanocomposite(22.15 nm),showing the coexistence of cubic and rutile tetragonal phases of Ag_(2)O and TiO_(2),respectively.Fourier-transform infrared spectroscopy(FTIR)showed the presence of functional groups of alco-hols,phenols,nitro compounds,and aromatic amines derived from the cultural filtrate of T.virens.Raman analysis revealed vibrational modes corresponding to Ag_(2)O and TiO_(2) nanoparticles.Distinct sharp emission peaks characteristic to Ti,Ag,and O were depicted using energy dispersive X-ray(EDX)analysis.X-ray photo-electron spectroscopy(XPS)confirmed the presence of elemental valence states and binding energies of Ag,Ti,and O in the mycogenic nanocomposite.Field emission scanning electron microscopy(FESEM)revealed ag-gregation of polydispersed Ag_(2)O-doped TiO_(2) bionanocomposite,displaying spherical-and cuboctahedron-shaped nanostructures with rough surfaces.High-resolution transmission electron microscopy(HRTEM)showed the presence of circular-,semi-spherical-,hexagonal-,and polygonal-shaped monodispersed Ag_(2)O NPs,with defined boundaries.The Ag_(2)O NPs were obviously deposited on the sheet-like TiO_(2) NPs.Selected area electron diffraction pattern implied the polycrystallinity of the as-synthesized bionanocomposite.A broad antibacterial spectrum of the prepared bionanocomposite was attained against foodborne pathogenic bacteria;Escherichia coli(12.05 mm),Salmonella enterica(11.26 mm),and Staphylococcus aureus(11.44 mm)and phytopathogenic bac-teria;Clavibacter michiganensis subsp.michiganensis(15.72 mm),C.michiganensis subsp.capsici(10.80 mm),streptomycin-sensitive and-resistant Xanthomonas citri pv.citri(14.11 and 14.53 mm,respectively),and streptomycin-sensitive and-resistant Pectobacterium carotovorum subsp.carotovorum(11.36 and 11.07 mm,respectively)using in vitro Kirby-Bauer method.Minimum inhibitory and minimum bactericidal concentrations were determined via a broth micro-dilution assay.FESEM revealed significant morphological alterations in bacterial cells upon treatment with the bionanocomposite,including deformed shape,rough surface,cell thin-ning,wrinkled cell wall,protrusions,cavitations,and cracks.These findings signify the successful mycosynthesis of Ag_(2)O-doped TiO_(2) bionanocomposite,which acted a potent antibacterial agent against a variety of foodborne and phytopathogenic bacteria,which could be employed in environmental,biomedical,agricultural,and food bio-processing applications.
