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Elsa B. Damonte - One of the best experts on this subject based on the ideXlab platform.
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antiviral activity against dengue virus of diverse classes of algal sulfated polysaccharides
International Journal of Biological Macromolecules, 2012Co-Authors: Carlos A Pujol, Bimalendu Ray, Sayani Ray, Elsa B. DamonteAbstract:Diverse classes of sulfated polysaccharides obtained from the red seaweeds (Rhodophyta) Grateloupia indica, Scinaia hatei and Gracilaria corticata, the brown seaweeds (Phaeophyta) Stoechospermum marginatum and Cystoseira indica and the green seaweed (Chlorophyta) Caulerpa racemosa were assayed for antiviral activity against the four serotypes of dengue virus (DENV). DENV-2 was the most susceptible serotype to all polysulfates, with Inhibitory Concentration 50% values in the range 0.12-20 μg/mL. The antiviral potency of the sulfated polysaccharides depended on the sulfate content, the position of sulfate group, the sugar composition, and the molar mass. Independently of the sugar composition, the antiviral effect was mainly exerted during DENV-2 adsorption and internalization.
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polysaccharides from padina tetrastromatica structural features chemical modification and antiviral activity
Carbohydrate Polymers, 2010Co-Authors: Paramita Karmakar, Elsa B. Damonte, Carlos A Pujol, Tuhin Ghosh, Bimalendu RayAbstract:Abstract Many viruses display affinity for cell surface heparan sulfate proteoglycans with biological relevance in virus entry. This raises the possibility of the application of sulfated polysaccharides in antiviral therapy. In this study, we have analyzed polysaccharide containing fractions derived from Padina tetrastromatica. A glucan containing α-(1 → 4)-linked glucopyranosyl residues, an alginate with apparent molecular mass of 50 kDa, and a fucoidan were isolated. Further sulfated derivatives of the fucoidan (S1–S3), which contained 0.8–1.2 sulfate groups per monomer unit showed Inhibitory activity against herpes simplex virus (HSV) types 1 and 2. Their Inhibitory Concentration 50% (IC50) values were in the range 0.30–1.05 μg/ml and they lacked cytotoxicity at Concentrations up to 1000 μg/ml. The antiviral effect was exerted during virus adsorption to the cell. The degree of sulfation seemed to play an important role because further sulfation of the isolated macromolecules largely influences their in vitro anti-HSV activity.
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galactan sulfate of grateloupia indica isolation structural features and antiviral activity
Phytochemistry, 2007Co-Authors: Kausik Chattopadhyay, Elsa B. Damonte, Carlos A Pujol, Cecilia Gabriela Mateu, Pinaki Mandal, Bimalendu RayAbstract:Abstract Natural compounds offer interesting pharmacological perspectives for antiviral drug development with regard to broad-spectrum antiviral properties and novel modes of action. In this study, we have analyzed polysaccharide fractions isolated from Grateloupia indica. The crude water extract (GiWE) as well as one fraction (F3) obtained by anion exchange chromatography had potent anti-HSV activity. Their Inhibitory Concentration 50% (IC50) values (0.12–1.06 μg/ml) were much lower than cytotoxic Concentration 50% values (>850 μg/ml). These fractions, which were effective antiviral inhibitors if added only during the adsorption period, had very low anticoagulant activity. Furthermore, they had no direct inactivating effect on virions in a virucidal assay. Chemical, chromatographic and spectroscopic methods showed that the active polysaccharide, which has an apparent molecular mass of 60 kDa and negative specific rotation [ α ] D 32 −16° (c 0.2, H2O), contains α-(1 → 4)- and α-(1 → 3)-linked galactopyranose residues. Sulfate groups, if present, are located mostly at C-2/6 of (1 → 4)- and C-4/6 of (1 → 3)-linked galactopyranosyl units, and are essential for the anti herpetic activity of this polymer.
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anti herpes simplex virus activity of sulfated galactans from the red seaweeds gymnogongrus griffithsiae and cryptonemia crenulata
International Journal of Biological Macromolecules, 2004Co-Authors: Laura B. Talarico, Carlos A Pujol, Rosiane G.m. Zibetti, Miguel D. Noseda, Maria Eugênia R. Duarte, Paula C S Faria, Luis A Scolaro, Elsa B. DamonteAbstract:This study presents the chemical composition and antiviral activity against herpes simplex virus type 1 (HSV-1) and 2 (HSV-2) of sulfated galactan crude extracts and main fractions obtained from two red seaweeds collected in Brazil, Gymnogongrus griffithsiae and Cryptonemia crenulata. Most of the eighteen tested products, including homogeneous kappa/iota/nu carrageenan and DL-galactan hybrid, exhibited antiherpetic activity with Inhibitory Concentration 50% (IC50) values in the range 0.5-5.6 microg/ml, as determined in a virus plaque reduction assay in Vero cells. The galactans lacked cytotoxic effects and showed a broad spectrum of antiviral activity against HSV-1 and HSV-2. No direct virus inactivation was observed after virion treatment with the galactans. The mode of action of these compounds could be mainly ascribed to an Inhibitory effect on virus adsorption. Most importantly, a significant protection against a murine vaginal infection with HSV-2 was afforded by topical treatment with the sulfated galactans.
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novel dl galactan hybrids from the red seaweed gymnogongrus torulosus are potent inhibitors of herpes simplex virus and dengue virus
Antiviral Chemistry & Chemotherapy, 2002Co-Authors: Carlos A Pujol, Marina Ciancia, José M. Estevez, Alberto S. Cerezo, Maria Josefina Carlucci, Elsa B. DamonteAbstract:A novel series of DL-galactan hybrids extracted from the red seaweed Gymnogongrus torulosus, was evaluated for its in vitro antiviral properties against herpes simplex virus type 2 (HSV-2) and dengue virus 2 (DEN-2). These compounds were very active against both viruses with Inhibitory Concentration 50% (IC50) values in the range 0.6–16 μg/ml for HSV-2 and 0.19–1.7 μg/ml for DEN-2, respectively, as determined in a virus plaque reduction assay in Vero cells. The DL-galactans lacked of cytotoxic effects, on stationary as well as on actively dividing cells, and anticoagulant properties. Some of the compounds showed a variable level of direct inactivating effect on both virions, with virucidal Concentration 50% values exceeding the IC50s obtained by plaque reduction assay. Full Inhibitory activity was achieved when the galactans were present during virus adsorption period, suggesting that the mode of action of these compounds is an interference in the binding of the surface envelope glycoprotein with the cell...
Bimalendu Ray - One of the best experts on this subject based on the ideXlab platform.
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antiviral activity against dengue virus of diverse classes of algal sulfated polysaccharides
International Journal of Biological Macromolecules, 2012Co-Authors: Carlos A Pujol, Bimalendu Ray, Sayani Ray, Elsa B. DamonteAbstract:Diverse classes of sulfated polysaccharides obtained from the red seaweeds (Rhodophyta) Grateloupia indica, Scinaia hatei and Gracilaria corticata, the brown seaweeds (Phaeophyta) Stoechospermum marginatum and Cystoseira indica and the green seaweed (Chlorophyta) Caulerpa racemosa were assayed for antiviral activity against the four serotypes of dengue virus (DENV). DENV-2 was the most susceptible serotype to all polysulfates, with Inhibitory Concentration 50% values in the range 0.12-20 μg/mL. The antiviral potency of the sulfated polysaccharides depended on the sulfate content, the position of sulfate group, the sugar composition, and the molar mass. Independently of the sugar composition, the antiviral effect was mainly exerted during DENV-2 adsorption and internalization.
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water extracted polysaccharides from azadirachta indica leaves structural features chemical modification and anti bovine herpesvirus type 1 bohv 1 activity
International Journal of Biological Macromolecules, 2010Co-Authors: Sudipta Saha, Sharmistha Sinha, Ligia Carla Faccin Galhardi, Kristie Aimi Yamamoto, Rosa Elisa Carvalho Linhares, Shruti S Bandyopadhyay, Carlos Nozawa, Bimalendu RayAbstract:Abstract In this study, we have analyzed the pectic arabinogalactan isolated from Azadirachta indica and its chemically sulfated derivative. The native polysaccharide had an apparent molecular mass of 80 kDa and is made up of (1 → 5)-/(1 → 3,5)-linked α- l -arabinosyl, (1 → 3)-/(1 → 6)-/(1 → 3,6)-linked β- d -galactosyl, and terminal-rhamnosyl and α- l- arabinosyl residues. These macromolecules showed activity against bovine herpesvirus type-1. Their Inhibitory Concentration 50% values ranging from 31.12 to 105.25 μg/ml were lower than the cytotoxicity values (>1600–1440 μg/ml). The anti-viral effect was exerted during virus adsorption to the cell. Anionic groups in particular the sulfate groups appeared to be very important for the anti-herpetic activity of these polymers.
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polysaccharides from padina tetrastromatica structural features chemical modification and antiviral activity
Carbohydrate Polymers, 2010Co-Authors: Paramita Karmakar, Elsa B. Damonte, Carlos A Pujol, Tuhin Ghosh, Bimalendu RayAbstract:Abstract Many viruses display affinity for cell surface heparan sulfate proteoglycans with biological relevance in virus entry. This raises the possibility of the application of sulfated polysaccharides in antiviral therapy. In this study, we have analyzed polysaccharide containing fractions derived from Padina tetrastromatica. A glucan containing α-(1 → 4)-linked glucopyranosyl residues, an alginate with apparent molecular mass of 50 kDa, and a fucoidan were isolated. Further sulfated derivatives of the fucoidan (S1–S3), which contained 0.8–1.2 sulfate groups per monomer unit showed Inhibitory activity against herpes simplex virus (HSV) types 1 and 2. Their Inhibitory Concentration 50% (IC50) values were in the range 0.30–1.05 μg/ml and they lacked cytotoxicity at Concentrations up to 1000 μg/ml. The antiviral effect was exerted during virus adsorption to the cell. The degree of sulfation seemed to play an important role because further sulfation of the isolated macromolecules largely influences their in vitro anti-HSV activity.
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polysaccharides from sargassum tenerrimum structural features chemical modification and anti viral activity
Phytochemistry, 2010Co-Authors: Sharmistha Sinha, Akram Astani, Tuhin Ghosh, Paul Schnitzler, Bimalendu RayAbstract:Abstract Herpes simplex viruses (HSVs) display affinity for cell-surface heparan sulfate proteoglycans with biological relevance in virus entry. Here, we exploit an approach to inhibiting HSV infection by using a sulfated fucoidan, and a guluronic acid-rich alginate derived from Sargassum tenerrimum , mimicking the active domain of the entry receptor. These macromolecules have apparent molecular masses of 30 ± 5 and 26 ± 5 kDa, respectively. They and their chemically sulfated derivatives showed activity against herpes simplex virus type 1 (HSV-1). Their Inhibitory Concentration 50% (IC 50 ) values were in the range 0.5–15 μg/ml and they lacked cytotoxicity at Concentrations up to 1000 μg/ml. The anti-HSV activity increased with increasing sulfate ester content. Our results suggest the feasibility of inhibiting HSV infection by blocking viral entry with polysaccharide having specific structure.
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galactan sulfate of grateloupia indica isolation structural features and antiviral activity
Phytochemistry, 2007Co-Authors: Kausik Chattopadhyay, Elsa B. Damonte, Carlos A Pujol, Cecilia Gabriela Mateu, Pinaki Mandal, Bimalendu RayAbstract:Abstract Natural compounds offer interesting pharmacological perspectives for antiviral drug development with regard to broad-spectrum antiviral properties and novel modes of action. In this study, we have analyzed polysaccharide fractions isolated from Grateloupia indica. The crude water extract (GiWE) as well as one fraction (F3) obtained by anion exchange chromatography had potent anti-HSV activity. Their Inhibitory Concentration 50% (IC50) values (0.12–1.06 μg/ml) were much lower than cytotoxic Concentration 50% values (>850 μg/ml). These fractions, which were effective antiviral inhibitors if added only during the adsorption period, had very low anticoagulant activity. Furthermore, they had no direct inactivating effect on virions in a virucidal assay. Chemical, chromatographic and spectroscopic methods showed that the active polysaccharide, which has an apparent molecular mass of 60 kDa and negative specific rotation [ α ] D 32 −16° (c 0.2, H2O), contains α-(1 → 4)- and α-(1 → 3)-linked galactopyranose residues. Sulfate groups, if present, are located mostly at C-2/6 of (1 → 4)- and C-4/6 of (1 → 3)-linked galactopyranosyl units, and are essential for the anti herpetic activity of this polymer.
Carlos A Pujol - One of the best experts on this subject based on the ideXlab platform.
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antiviral activity against dengue virus of diverse classes of algal sulfated polysaccharides
International Journal of Biological Macromolecules, 2012Co-Authors: Carlos A Pujol, Bimalendu Ray, Sayani Ray, Elsa B. DamonteAbstract:Diverse classes of sulfated polysaccharides obtained from the red seaweeds (Rhodophyta) Grateloupia indica, Scinaia hatei and Gracilaria corticata, the brown seaweeds (Phaeophyta) Stoechospermum marginatum and Cystoseira indica and the green seaweed (Chlorophyta) Caulerpa racemosa were assayed for antiviral activity against the four serotypes of dengue virus (DENV). DENV-2 was the most susceptible serotype to all polysulfates, with Inhibitory Concentration 50% values in the range 0.12-20 μg/mL. The antiviral potency of the sulfated polysaccharides depended on the sulfate content, the position of sulfate group, the sugar composition, and the molar mass. Independently of the sugar composition, the antiviral effect was mainly exerted during DENV-2 adsorption and internalization.
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polysaccharides from padina tetrastromatica structural features chemical modification and antiviral activity
Carbohydrate Polymers, 2010Co-Authors: Paramita Karmakar, Elsa B. Damonte, Carlos A Pujol, Tuhin Ghosh, Bimalendu RayAbstract:Abstract Many viruses display affinity for cell surface heparan sulfate proteoglycans with biological relevance in virus entry. This raises the possibility of the application of sulfated polysaccharides in antiviral therapy. In this study, we have analyzed polysaccharide containing fractions derived from Padina tetrastromatica. A glucan containing α-(1 → 4)-linked glucopyranosyl residues, an alginate with apparent molecular mass of 50 kDa, and a fucoidan were isolated. Further sulfated derivatives of the fucoidan (S1–S3), which contained 0.8–1.2 sulfate groups per monomer unit showed Inhibitory activity against herpes simplex virus (HSV) types 1 and 2. Their Inhibitory Concentration 50% (IC50) values were in the range 0.30–1.05 μg/ml and they lacked cytotoxicity at Concentrations up to 1000 μg/ml. The antiviral effect was exerted during virus adsorption to the cell. The degree of sulfation seemed to play an important role because further sulfation of the isolated macromolecules largely influences their in vitro anti-HSV activity.
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galactan sulfate of grateloupia indica isolation structural features and antiviral activity
Phytochemistry, 2007Co-Authors: Kausik Chattopadhyay, Elsa B. Damonte, Carlos A Pujol, Cecilia Gabriela Mateu, Pinaki Mandal, Bimalendu RayAbstract:Abstract Natural compounds offer interesting pharmacological perspectives for antiviral drug development with regard to broad-spectrum antiviral properties and novel modes of action. In this study, we have analyzed polysaccharide fractions isolated from Grateloupia indica. The crude water extract (GiWE) as well as one fraction (F3) obtained by anion exchange chromatography had potent anti-HSV activity. Their Inhibitory Concentration 50% (IC50) values (0.12–1.06 μg/ml) were much lower than cytotoxic Concentration 50% values (>850 μg/ml). These fractions, which were effective antiviral inhibitors if added only during the adsorption period, had very low anticoagulant activity. Furthermore, they had no direct inactivating effect on virions in a virucidal assay. Chemical, chromatographic and spectroscopic methods showed that the active polysaccharide, which has an apparent molecular mass of 60 kDa and negative specific rotation [ α ] D 32 −16° (c 0.2, H2O), contains α-(1 → 4)- and α-(1 → 3)-linked galactopyranose residues. Sulfate groups, if present, are located mostly at C-2/6 of (1 → 4)- and C-4/6 of (1 → 3)-linked galactopyranosyl units, and are essential for the anti herpetic activity of this polymer.
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anti herpes simplex virus activity of sulfated galactans from the red seaweeds gymnogongrus griffithsiae and cryptonemia crenulata
International Journal of Biological Macromolecules, 2004Co-Authors: Laura B. Talarico, Carlos A Pujol, Rosiane G.m. Zibetti, Miguel D. Noseda, Maria Eugênia R. Duarte, Paula C S Faria, Luis A Scolaro, Elsa B. DamonteAbstract:This study presents the chemical composition and antiviral activity against herpes simplex virus type 1 (HSV-1) and 2 (HSV-2) of sulfated galactan crude extracts and main fractions obtained from two red seaweeds collected in Brazil, Gymnogongrus griffithsiae and Cryptonemia crenulata. Most of the eighteen tested products, including homogeneous kappa/iota/nu carrageenan and DL-galactan hybrid, exhibited antiherpetic activity with Inhibitory Concentration 50% (IC50) values in the range 0.5-5.6 microg/ml, as determined in a virus plaque reduction assay in Vero cells. The galactans lacked cytotoxic effects and showed a broad spectrum of antiviral activity against HSV-1 and HSV-2. No direct virus inactivation was observed after virion treatment with the galactans. The mode of action of these compounds could be mainly ascribed to an Inhibitory effect on virus adsorption. Most importantly, a significant protection against a murine vaginal infection with HSV-2 was afforded by topical treatment with the sulfated galactans.
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novel dl galactan hybrids from the red seaweed gymnogongrus torulosus are potent inhibitors of herpes simplex virus and dengue virus
Antiviral Chemistry & Chemotherapy, 2002Co-Authors: Carlos A Pujol, Marina Ciancia, José M. Estevez, Alberto S. Cerezo, Maria Josefina Carlucci, Elsa B. DamonteAbstract:A novel series of DL-galactan hybrids extracted from the red seaweed Gymnogongrus torulosus, was evaluated for its in vitro antiviral properties against herpes simplex virus type 2 (HSV-2) and dengue virus 2 (DEN-2). These compounds were very active against both viruses with Inhibitory Concentration 50% (IC50) values in the range 0.6–16 μg/ml for HSV-2 and 0.19–1.7 μg/ml for DEN-2, respectively, as determined in a virus plaque reduction assay in Vero cells. The DL-galactans lacked of cytotoxic effects, on stationary as well as on actively dividing cells, and anticoagulant properties. Some of the compounds showed a variable level of direct inactivating effect on both virions, with virucidal Concentration 50% values exceeding the IC50s obtained by plaque reduction assay. Full Inhibitory activity was achieved when the galactans were present during virus adsorption period, suggesting that the mode of action of these compounds is an interference in the binding of the surface envelope glycoprotein with the cell...
Sharmistha Sinha - One of the best experts on this subject based on the ideXlab platform.
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water extracted polysaccharides from azadirachta indica leaves structural features chemical modification and anti bovine herpesvirus type 1 bohv 1 activity
International Journal of Biological Macromolecules, 2010Co-Authors: Sudipta Saha, Sharmistha Sinha, Ligia Carla Faccin Galhardi, Kristie Aimi Yamamoto, Rosa Elisa Carvalho Linhares, Shruti S Bandyopadhyay, Carlos Nozawa, Bimalendu RayAbstract:Abstract In this study, we have analyzed the pectic arabinogalactan isolated from Azadirachta indica and its chemically sulfated derivative. The native polysaccharide had an apparent molecular mass of 80 kDa and is made up of (1 → 5)-/(1 → 3,5)-linked α- l -arabinosyl, (1 → 3)-/(1 → 6)-/(1 → 3,6)-linked β- d -galactosyl, and terminal-rhamnosyl and α- l- arabinosyl residues. These macromolecules showed activity against bovine herpesvirus type-1. Their Inhibitory Concentration 50% values ranging from 31.12 to 105.25 μg/ml were lower than the cytotoxicity values (>1600–1440 μg/ml). The anti-viral effect was exerted during virus adsorption to the cell. Anionic groups in particular the sulfate groups appeared to be very important for the anti-herpetic activity of these polymers.
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polysaccharides from sargassum tenerrimum structural features chemical modification and anti viral activity
Phytochemistry, 2010Co-Authors: Sharmistha Sinha, Akram Astani, Tuhin Ghosh, Paul Schnitzler, Bimalendu RayAbstract:Abstract Herpes simplex viruses (HSVs) display affinity for cell-surface heparan sulfate proteoglycans with biological relevance in virus entry. Here, we exploit an approach to inhibiting HSV infection by using a sulfated fucoidan, and a guluronic acid-rich alginate derived from Sargassum tenerrimum , mimicking the active domain of the entry receptor. These macromolecules have apparent molecular masses of 30 ± 5 and 26 ± 5 kDa, respectively. They and their chemically sulfated derivatives showed activity against herpes simplex virus type 1 (HSV-1). Their Inhibitory Concentration 50% (IC 50 ) values were in the range 0.5–15 μg/ml and they lacked cytotoxicity at Concentrations up to 1000 μg/ml. The anti-HSV activity increased with increasing sulfate ester content. Our results suggest the feasibility of inhibiting HSV infection by blocking viral entry with polysaccharide having specific structure.
Muhammad Riaz - One of the best experts on this subject based on the ideXlab platform.
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gc ms profiling in vitro antioxidant antimicrobial and haemolytic activities of smilax macrophylla leaves
Arabian Journal of Chemistry, 2017Co-Authors: Muhammad Zubair, Komal Rizwan, Umer Rashid, Rabia Saeed, Anum Ayesha Saeed, Nasir Rasool, Muhammad RiazAbstract:Abstract The current study has been designed to appraise the antioxidant, antimicrobial and haemolytic potential of Smilax macrophylla leaves. The n- hexane fraction was analysed by Gas Chromatography/Mass Spectrometer which revealed the presence of 38 compounds. All examined extracts and fractions of plant leaves showed significant antimicrobial activity. The haemolytic effect of the plant was found to be in a range of 3.41–8.48%. S. macrophylla leaves contained substantial level of total phenolic contents (2.2–6.2 Gallic acid equivalent mg/g) and total flavonoid contents (1.2–4.5 Catechin, mg/g) of dry plant matter. Leaf extract and fractions also exhibited a good antioxidant potential when measured by DPPH radical scavenging assay (Inhibitory Concentration 50% = 33.4–72.3 μg/mL). The antioxidant activity of plant extracts was also studied using sunflower oil as an oxidative substrate and found that it stabilized the oil. Significant ( p S. macrophylla could be used as a source for the exploration of new antimicrobial, antioxidant agents, functional food and nutraceutical applications.