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Gabriela Elena Giudice - One of the best experts on this subject based on the ideXlab platform.

  • Spore Morphology and wall ultrastructure of Lycopodiaceae from northwest Argentina
    2016
    Co-Authors: J.p. Ramos Giacosa, Marta A. Morbelli, Gabriela Elena Giudice, Daniel Alejandro Gorrer
    Abstract:

    Abstract Spores of Lycopodiaceae species growing in northwest Argentina were studied. The taxa are: subfam. Lycopodioideae: Austrolycopodium erectum , Diphasiastrum thyoides , and Lycopodium clavatum subsp. clavatum ; subfam. Lycopodielloideae: Palhinhaea cernua ; and subfam. Huperzioideae: Phlegmariurus mandiocanus , Phlegmariurus phylicifolius , Phlegmariurus reflexus , Phlegmariurus saururus , and Phlegmariurus sotae . The study is based on herbarium material; Spores were examined with light microscope (LM), scanning (SEM) and transmission electron microscope (TEM). Spores are trilete 24–44 μm in equatorial diameter and 14–35 μm in polar diameter. The exoSpore is 0.5–9.5 μm thick and one or two-layered, depending on the analyzed area of the Spore. The ornamentation can be reticulate, rugulate, foveolate, fossulate or foveolate–fossulate. The periSpore is 30–190 nm thick, one or two-layered, and is only visible with TEM. The presence of this wall is mentioned and described for the first time in Phlegmariurus phylicifolius . In the studied species, Spore ornamentation of the proximal face is different from or less complex than the distal face. The results evidence the significance of Spore Morphology in Lycopodiaceae systematics, particularly at subfamilial level.

  • Spore Morphology and wall ultrastructure of anemia swartz species anemiaceae from argentina
    2012
    Co-Authors: J.p. Ramos Giacosa, Marta A. Morbelli, Gabriela Elena Giudice
    Abstract:

    Abstract Spores of Anemia species that grow in Argentina are studied. The country corresponds to the southern limit in the distribution of the genus where nine species have been reported: Anemia australis, A. herzogii, A. myriophylla, A. phyllitidis var. phyllitidis, A. phyllitidis var. tweedieana, A. simplicior, A. tomentosa var. anthriscifolia, A. tomentosa var. tomentosa and A. wettsteinii. The material was examined using light microscope (LM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The Spores are trilete of 42–114 μm in equatorial diameter and 34–106 μm in polar diameter. The exoSpore is 1.2–7 μm thick, two-layered; and two different ornamentations are observed: narrow and parallel ridges bearing baculae separated by wide and smooth grooves or parallel wide ridges with several ornamentations separated by narrow and smooth grooves. The periSpore is 0.2–1.1 μm thick, two-layered, and it may be plane or echinate with echina of variable sizes and shapes depending on the taxa analyzed. Perforations are also present on the periSpore surface. The differences found in exoSpore and periSpore Morphology and ultrastructure could be valuable characters for systematic, phylogenetic and paleobotanical purposes.

  • Spore Morphology and wall ultrastructure of Trachypteris species (Pteridaceae)
    2011
    Co-Authors: J.p. Ramos Giacosa, Marta A. Morbelli, Gabriela Elena Giudice
    Abstract:

    Trachypteris is a small genus consisting of four species native to America and Madagascar: Trachypteris induta , T. pinnata , T. gilliana , and T. drakeana . The Spores of the genus were studied using light microscopy and scanning and transmission electron microscopy. They are trilete, triangular to globose, with equatorial diameter of 29–58 μm and polar diameter of 26–53 μm. The exoSpore is 0.5–1.1 μm thick, plane, and two-layered. The periSpore is 0.3–6.8 μm thick and two-layered. Depending on the species, two different ornamentations were observed: cristated with partially fused cristae, and ridged with partially fused ridges, forming an incomplete reticulum. Globules immersed in the periSpore were occasionally observed. The systematic value of the Trachypteris Spores is discussed, and their Morphology and ultrastructure are compared with those of other related cheilanthoid ferns. The palynological characteristics presented here may be useful for phylogenetic studies within the Pteridaceae, and particularly within the cheilanthoid ferns.

  • Spore Morphology and ultrastructure of cyathea cyatheaceae pteridophyta species from southern south america
    2010
    Co-Authors: Gonzalo Javier Marquez, Marta A. Morbelli, Gabriela Elena Giudice
    Abstract:

    Abstract Spore sculpture and wall structure of eight Cyathea (Cyatheaceae) species from southern South America were studied using light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. Two layers, i.e. an inner and an outer layer, were observed in the periSpore. The inner layer has two strata: the inner stratum is attached to the exoSpore and composed of rodlets tangentially oriented to the Spore surface and randomly intermixed; the outer stratum consists of a three-dimensional network of rodlets with either free or fused distal edges forming spinules. The outer layer is thin, darkly contrasted and covers the rodlets. In most cases, the exoSpore has two layers and a pitted surface. In Cyathea atrovirens, the exoSpore surface is smooth, while in C. delgadii and C. myriotricha it is verrucate. The homogeneity of periSpore features within the genus Cyathea is evident, while exoSpore features are heterogeneous. The exoSpore has different kinds of surfa...

  • Spore Morphology and wall ultrastructure of hymenophyllaceae link pteridophyta from north west argentina
    2010
    Co-Authors: Marta A. Morbelli, Maria Raquel Pineiro, Gabriela Elena Giudice
    Abstract:

    Abstract The family Hymenophyllaceae is represented in the study area by six species in two genera, Hymenophyllum J. E. Smith and Trichomanes L. The study was based on herbarium material and Spores were studied under light microscope (LM), scanning electron microscope (SEM) and transmission electron microscope (TEM). Both genera have trilete Spores, 23 to 45 μm in equatorial diameter, with an ornamentation of echinulae and cones in Hymenophyllum and of verrucae, gemmae and granules in Trichomanes. Mature Spores have a sporoderm composed of a periSpore, an exoSpore and a fibrillar endoSpore; the exoSpore is 0.5 to 2.5 μm thick, compact and with an irregular margin. In some cases radial channels and other channels associated with the middle and inner parts of the laesurae were evident. A series of cavities filled with an opaque content line the inner margin of the exoSpore. The periSpore is 20 to 400 nm thick and unevenly differentiated along the surface of a same Spore. Under TEM, two main differentially c...

Ting-lin Huang - One of the best experts on this subject based on the ideXlab platform.

  • inactivation of three genera of dominant fungal Spores in groundwater using chlorine dioxide effectiveness influencing factors and mechanisms
    2017
    Co-Authors: Xiang-qian Xu, Ting-lin Huang
    Abstract:

    Abstract Fungi in aquatic environments received more attention recently; therefore, the characteristics of inactivation of fungal Spores by widely used disinfectants are quite important. Nonetheless, the inactivation efficacy of fungal Spores by chlorine dioxide is poorly known. In this study, the effectiveness of chlorine dioxide at inactivation of three dominant genera of fungal Spores isolated from drinking groundwater and the effects of pH, temperature, chlorine dioxide concentration, and humic acid were evaluated. The inactivation mechanisms were explored by analyzing the leakage of intracellular substances, the increase in extracellular adenosine triphosphate (ATP), deoxyribonucleic acid (DNA), and proteins as well as the changes in Spore Morphology. The kinetics of inactivation by chlorine dioxide fitted the Chick-Watson model, and different fungal species showed different resistance to chlorine dioxide inactivation, which was in the following order: Cladosporium sp.> Trichoderma sp. > Penicillium sp., which are much more resistant than Escherichia coli . Regarding the three genera of fungal Spores used in this study, chlorine dioxide was more effective at inactivation of fungal Spores than chlorine. The effect of disinfectant concentration and temperature was positive, and the impact of pH levels (6.0 and 7.0) was insignificant, whereas the influence of water matrices on the inactivation efficiency was negative. The increased concentration of characteristic extracellular substances and changes of Spore Morphology were observed after inactivation with chlorine dioxide and were due to cell wall and cell membrane damage in fungal Spores, causing the leakage of intracellular substances and death of a fungal Spore.

  • inactivation of three genera of dominant fungal Spores in groundwater using chlorine dioxide effectiveness influencing factors and mechanisms
    2017
    Co-Authors: Xiang-qian Xu, Ting-lin Huang
    Abstract:

    Abstract Fungi in aquatic environments received more attention recently; therefore, the characteristics of inactivation of fungal Spores by widely used disinfectants are quite important. Nonetheless, the inactivation efficacy of fungal Spores by chlorine dioxide is poorly known. In this study, the effectiveness of chlorine dioxide at inactivation of three dominant genera of fungal Spores isolated from drinking groundwater and the effects of pH, temperature, chlorine dioxide concentration, and humic acid were evaluated. The inactivation mechanisms were explored by analyzing the leakage of intracellular substances, the increase in extracellular adenosine triphosphate (ATP), deoxyribonucleic acid (DNA), and proteins as well as the changes in Spore Morphology. The kinetics of inactivation by chlorine dioxide fitted the Chick-Watson model, and different fungal species showed different resistance to chlorine dioxide inactivation, which was in the following order: Cladosporium sp.> Trichoderma sp. > Penicillium sp., which are much more resistant than Escherichia coli . Regarding the three genera of fungal Spores used in this study, chlorine dioxide was more effective at inactivation of fungal Spores than chlorine. The effect of disinfectant concentration and temperature was positive, and the impact of pH levels (6.0 and 7.0) was insignificant, whereas the influence of water matrices on the inactivation efficiency was negative. The increased concentration of characteristic extracellular substances and changes of Spore Morphology were observed after inactivation with chlorine dioxide and were due to cell wall and cell membrane damage in fungal Spores, causing the leakage of intracellular substances and death of a fungal Spore.

Marta A. Morbelli - One of the best experts on this subject based on the ideXlab platform.

  • Spore Morphology and wall ultrastructure of Lycopodiaceae from northwest Argentina
    2016
    Co-Authors: J.p. Ramos Giacosa, Marta A. Morbelli, Gabriela Elena Giudice, Daniel Alejandro Gorrer
    Abstract:

    Abstract Spores of Lycopodiaceae species growing in northwest Argentina were studied. The taxa are: subfam. Lycopodioideae: Austrolycopodium erectum , Diphasiastrum thyoides , and Lycopodium clavatum subsp. clavatum ; subfam. Lycopodielloideae: Palhinhaea cernua ; and subfam. Huperzioideae: Phlegmariurus mandiocanus , Phlegmariurus phylicifolius , Phlegmariurus reflexus , Phlegmariurus saururus , and Phlegmariurus sotae . The study is based on herbarium material; Spores were examined with light microscope (LM), scanning (SEM) and transmission electron microscope (TEM). Spores are trilete 24–44 μm in equatorial diameter and 14–35 μm in polar diameter. The exoSpore is 0.5–9.5 μm thick and one or two-layered, depending on the analyzed area of the Spore. The ornamentation can be reticulate, rugulate, foveolate, fossulate or foveolate–fossulate. The periSpore is 30–190 nm thick, one or two-layered, and is only visible with TEM. The presence of this wall is mentioned and described for the first time in Phlegmariurus phylicifolius . In the studied species, Spore ornamentation of the proximal face is different from or less complex than the distal face. The results evidence the significance of Spore Morphology in Lycopodiaceae systematics, particularly at subfamilial level.

  • Spore Morphology and ultrastructure of dennstaedtiaceae from paranaense phytogeographic province i genus dennstaedtia
    2016
    Co-Authors: Agustina Yanez, Gonzalo Javier Marquez, Marta A. Morbelli
    Abstract:

    Abstract The Spore Morphology and wall structure of Dennstaedtia species from the Phytogeographic Paranaense Province: Dennstaedtia cicutaria, D. cornuta, D. dissecta, D. globulifera, D. obtusifolia were studied using light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The Spores are trilete, brown, triangular in polar view and plane-hemispheric to plane-convex in equatorial view. The exoSpore is homogeneous, with two layers. The periSpore has an alveolar structure and is composed of one or two layers. The outer periSpore surface bears the sculpture, which has elements of varied shapes (verrucae, ridges, reticles), an different sizes and fusion. This variation allows characterize species or groups of species. Three different types of periSpore ornamentation can be found: 1. Verrucate with verrucae covered with rodlets; 2. Verrucate-rugate with verrucae and smooth ridges; 3. Reticulate. The Spores constitute an important source of characters with a systematic value for the genus Dennstaedtia and they are a useful tool for the identification of herbarium samples.

  • Spore Morphology and wall ultrastructure of anemia swartz species anemiaceae from argentina
    2012
    Co-Authors: J.p. Ramos Giacosa, Marta A. Morbelli, Gabriela Elena Giudice
    Abstract:

    Abstract Spores of Anemia species that grow in Argentina are studied. The country corresponds to the southern limit in the distribution of the genus where nine species have been reported: Anemia australis, A. herzogii, A. myriophylla, A. phyllitidis var. phyllitidis, A. phyllitidis var. tweedieana, A. simplicior, A. tomentosa var. anthriscifolia, A. tomentosa var. tomentosa and A. wettsteinii. The material was examined using light microscope (LM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The Spores are trilete of 42–114 μm in equatorial diameter and 34–106 μm in polar diameter. The exoSpore is 1.2–7 μm thick, two-layered; and two different ornamentations are observed: narrow and parallel ridges bearing baculae separated by wide and smooth grooves or parallel wide ridges with several ornamentations separated by narrow and smooth grooves. The periSpore is 0.2–1.1 μm thick, two-layered, and it may be plane or echinate with echina of variable sizes and shapes depending on the taxa analyzed. Perforations are also present on the periSpore surface. The differences found in exoSpore and periSpore Morphology and ultrastructure could be valuable characters for systematic, phylogenetic and paleobotanical purposes.

  • Spore Morphology and wall ultrastructure of Trachypteris species (Pteridaceae)
    2011
    Co-Authors: J.p. Ramos Giacosa, Marta A. Morbelli, Gabriela Elena Giudice
    Abstract:

    Trachypteris is a small genus consisting of four species native to America and Madagascar: Trachypteris induta , T. pinnata , T. gilliana , and T. drakeana . The Spores of the genus were studied using light microscopy and scanning and transmission electron microscopy. They are trilete, triangular to globose, with equatorial diameter of 29–58 μm and polar diameter of 26–53 μm. The exoSpore is 0.5–1.1 μm thick, plane, and two-layered. The periSpore is 0.3–6.8 μm thick and two-layered. Depending on the species, two different ornamentations were observed: cristated with partially fused cristae, and ridged with partially fused ridges, forming an incomplete reticulum. Globules immersed in the periSpore were occasionally observed. The systematic value of the Trachypteris Spores is discussed, and their Morphology and ultrastructure are compared with those of other related cheilanthoid ferns. The palynological characteristics presented here may be useful for phylogenetic studies within the Pteridaceae, and particularly within the cheilanthoid ferns.

  • Spore Morphology and ultrastructure of cyathea cyatheaceae pteridophyta species from southern south america
    2010
    Co-Authors: Gonzalo Javier Marquez, Marta A. Morbelli, Gabriela Elena Giudice
    Abstract:

    Abstract Spore sculpture and wall structure of eight Cyathea (Cyatheaceae) species from southern South America were studied using light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. Two layers, i.e. an inner and an outer layer, were observed in the periSpore. The inner layer has two strata: the inner stratum is attached to the exoSpore and composed of rodlets tangentially oriented to the Spore surface and randomly intermixed; the outer stratum consists of a three-dimensional network of rodlets with either free or fused distal edges forming spinules. The outer layer is thin, darkly contrasted and covers the rodlets. In most cases, the exoSpore has two layers and a pitted surface. In Cyathea atrovirens, the exoSpore surface is smooth, while in C. delgadii and C. myriotricha it is verrucate. The homogeneity of periSpore features within the genus Cyathea is evident, while exoSpore features are heterogeneous. The exoSpore has different kinds of surfa...

J.p. Ramos Giacosa - One of the best experts on this subject based on the ideXlab platform.

  • Spore Morphology and wall ultrastructure of lomariocycas blechnaceae species from america
    2019
    Co-Authors: J.p. Ramos Giacosa
    Abstract:

    Abstract The Spores of 11 species of Lomariocycas that grow in America were studied: Lomariocycas aurata , L. columbiensis , L. cycadifolia , L. insularis , L. magellanica , L. moritziana , L. rufa, L. schomburgkii, L. shaferi , L. underwoodiana and L. werckleana. The study was performed with light microscope (LM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The Spores are monolete of 61–100 μm in equatorial diameter and 40–79 μm in polar diameter. The exoSpore is 1.5–4.8 μm thick and in section is two-layered. The periSpore is folded, two types of folds were observed in the different species analyzed and also they could be fused in different ways. In section, it is 0.5–13.8 μm thick and is two-layered. The outer layer is single stratified and the inner layer is three-stratified. The Spores of some species are illustrated and described for the first time. Moreover, the sporoderm ultrastructure of L. underwodiana was not studied until now. The differences found in periSpore Morphology and ultrastructure could be valuable characters for systematic and phylogenetic purposes.

  • Spore Morphology and wall ultrastructure of Lycopodiaceae from northwest Argentina
    2016
    Co-Authors: J.p. Ramos Giacosa, Marta A. Morbelli, Gabriela Elena Giudice, Daniel Alejandro Gorrer
    Abstract:

    Abstract Spores of Lycopodiaceae species growing in northwest Argentina were studied. The taxa are: subfam. Lycopodioideae: Austrolycopodium erectum , Diphasiastrum thyoides , and Lycopodium clavatum subsp. clavatum ; subfam. Lycopodielloideae: Palhinhaea cernua ; and subfam. Huperzioideae: Phlegmariurus mandiocanus , Phlegmariurus phylicifolius , Phlegmariurus reflexus , Phlegmariurus saururus , and Phlegmariurus sotae . The study is based on herbarium material; Spores were examined with light microscope (LM), scanning (SEM) and transmission electron microscope (TEM). Spores are trilete 24–44 μm in equatorial diameter and 14–35 μm in polar diameter. The exoSpore is 0.5–9.5 μm thick and one or two-layered, depending on the analyzed area of the Spore. The ornamentation can be reticulate, rugulate, foveolate, fossulate or foveolate–fossulate. The periSpore is 30–190 nm thick, one or two-layered, and is only visible with TEM. The presence of this wall is mentioned and described for the first time in Phlegmariurus phylicifolius . In the studied species, Spore ornamentation of the proximal face is different from or less complex than the distal face. The results evidence the significance of Spore Morphology in Lycopodiaceae systematics, particularly at subfamilial level.

  • Spore Morphology and wall ultrastructure of anemia swartz species anemiaceae from argentina
    2012
    Co-Authors: J.p. Ramos Giacosa, Marta A. Morbelli, Gabriela Elena Giudice
    Abstract:

    Abstract Spores of Anemia species that grow in Argentina are studied. The country corresponds to the southern limit in the distribution of the genus where nine species have been reported: Anemia australis, A. herzogii, A. myriophylla, A. phyllitidis var. phyllitidis, A. phyllitidis var. tweedieana, A. simplicior, A. tomentosa var. anthriscifolia, A. tomentosa var. tomentosa and A. wettsteinii. The material was examined using light microscope (LM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The Spores are trilete of 42–114 μm in equatorial diameter and 34–106 μm in polar diameter. The exoSpore is 1.2–7 μm thick, two-layered; and two different ornamentations are observed: narrow and parallel ridges bearing baculae separated by wide and smooth grooves or parallel wide ridges with several ornamentations separated by narrow and smooth grooves. The periSpore is 0.2–1.1 μm thick, two-layered, and it may be plane or echinate with echina of variable sizes and shapes depending on the taxa analyzed. Perforations are also present on the periSpore surface. The differences found in exoSpore and periSpore Morphology and ultrastructure could be valuable characters for systematic, phylogenetic and paleobotanical purposes.

  • Spore Morphology and wall ultrastructure of Trachypteris species (Pteridaceae)
    2011
    Co-Authors: J.p. Ramos Giacosa, Marta A. Morbelli, Gabriela Elena Giudice
    Abstract:

    Trachypteris is a small genus consisting of four species native to America and Madagascar: Trachypteris induta , T. pinnata , T. gilliana , and T. drakeana . The Spores of the genus were studied using light microscopy and scanning and transmission electron microscopy. They are trilete, triangular to globose, with equatorial diameter of 29–58 μm and polar diameter of 26–53 μm. The exoSpore is 0.5–1.1 μm thick, plane, and two-layered. The periSpore is 0.3–6.8 μm thick and two-layered. Depending on the species, two different ornamentations were observed: cristated with partially fused cristae, and ridged with partially fused ridges, forming an incomplete reticulum. Globules immersed in the periSpore were occasionally observed. The systematic value of the Trachypteris Spores is discussed, and their Morphology and ultrastructure are compared with those of other related cheilanthoid ferns. The palynological characteristics presented here may be useful for phylogenetic studies within the Pteridaceae, and particularly within the cheilanthoid ferns.

  • Spore Morphology and wall ultrastructure of blechnum l species from north west argentina
    2009
    Co-Authors: J.p. Ramos Giacosa, Marta A. Morbelli, Gabriela Elena Giudice
    Abstract:

    Abstract Spores of Blechnaceae species that grow in northwest Argentina were studied. These are: Blechnum australe subsp. auriculatum, B. austrobrasilianum, B. brasiliense, B. cordatum, B. laevigatum, B. mochaenum var. squamipes, B. occidentale, B penna-marina, B. sprucei and B. tabulare. The study was performed with light microscope (LM), transmission electron microscope (TEM) and scanning electron microscope (SEM). The Spores are monolete of 31.5–104 µm in equatorial diameter and 21–75 µm in polar diameter. The exoSpore is 0.6–3.5 µm thick, plane or scabrate and in section it is two-layered. According to the plane of sectioning, and especially in immature material, interwoven channels are evident. The exoSpore structure is blechnoid and similar in all taxa analysed. The periSpore is 0.4–3.0 µm thick and plane, rugulated or folded. Its surface has verrucae, rugulae and perforations. In section it is two-layered. The outer layer is single stratified and the inner layer is three-stratified. Scattered spherules are also present on the surface and globules are detected in the periSpore. In the analysed taxa the periSpore has the greatest variability at specific and infraspecific levels and five structural types are observed. Differences were found among the studied taxa in the characteristics of the medium stratum. Additionally, in B. cordatum the structural elements are also superficially observed on and between the folds. The differentiated structural types would not find any correspondence with the ornamentation patterns of the species here analyzed. The diversification found in Spore characteristics observed in this study, could be valuable for systematic and phylogenetic studies.

Xiang-qian Xu - One of the best experts on this subject based on the ideXlab platform.

  • inactivation of three genera of dominant fungal Spores in groundwater using chlorine dioxide effectiveness influencing factors and mechanisms
    2017
    Co-Authors: Xiang-qian Xu, Ting-lin Huang
    Abstract:

    Abstract Fungi in aquatic environments received more attention recently; therefore, the characteristics of inactivation of fungal Spores by widely used disinfectants are quite important. Nonetheless, the inactivation efficacy of fungal Spores by chlorine dioxide is poorly known. In this study, the effectiveness of chlorine dioxide at inactivation of three dominant genera of fungal Spores isolated from drinking groundwater and the effects of pH, temperature, chlorine dioxide concentration, and humic acid were evaluated. The inactivation mechanisms were explored by analyzing the leakage of intracellular substances, the increase in extracellular adenosine triphosphate (ATP), deoxyribonucleic acid (DNA), and proteins as well as the changes in Spore Morphology. The kinetics of inactivation by chlorine dioxide fitted the Chick-Watson model, and different fungal species showed different resistance to chlorine dioxide inactivation, which was in the following order: Cladosporium sp.> Trichoderma sp. > Penicillium sp., which are much more resistant than Escherichia coli . Regarding the three genera of fungal Spores used in this study, chlorine dioxide was more effective at inactivation of fungal Spores than chlorine. The effect of disinfectant concentration and temperature was positive, and the impact of pH levels (6.0 and 7.0) was insignificant, whereas the influence of water matrices on the inactivation efficiency was negative. The increased concentration of characteristic extracellular substances and changes of Spore Morphology were observed after inactivation with chlorine dioxide and were due to cell wall and cell membrane damage in fungal Spores, causing the leakage of intracellular substances and death of a fungal Spore.

  • inactivation of three genera of dominant fungal Spores in groundwater using chlorine dioxide effectiveness influencing factors and mechanisms
    2017
    Co-Authors: Xiang-qian Xu, Ting-lin Huang
    Abstract:

    Abstract Fungi in aquatic environments received more attention recently; therefore, the characteristics of inactivation of fungal Spores by widely used disinfectants are quite important. Nonetheless, the inactivation efficacy of fungal Spores by chlorine dioxide is poorly known. In this study, the effectiveness of chlorine dioxide at inactivation of three dominant genera of fungal Spores isolated from drinking groundwater and the effects of pH, temperature, chlorine dioxide concentration, and humic acid were evaluated. The inactivation mechanisms were explored by analyzing the leakage of intracellular substances, the increase in extracellular adenosine triphosphate (ATP), deoxyribonucleic acid (DNA), and proteins as well as the changes in Spore Morphology. The kinetics of inactivation by chlorine dioxide fitted the Chick-Watson model, and different fungal species showed different resistance to chlorine dioxide inactivation, which was in the following order: Cladosporium sp.> Trichoderma sp. > Penicillium sp., which are much more resistant than Escherichia coli . Regarding the three genera of fungal Spores used in this study, chlorine dioxide was more effective at inactivation of fungal Spores than chlorine. The effect of disinfectant concentration and temperature was positive, and the impact of pH levels (6.0 and 7.0) was insignificant, whereas the influence of water matrices on the inactivation efficiency was negative. The increased concentration of characteristic extracellular substances and changes of Spore Morphology were observed after inactivation with chlorine dioxide and were due to cell wall and cell membrane damage in fungal Spores, causing the leakage of intracellular substances and death of a fungal Spore.