Browsing by Author "Silva-Filho, Edson C."
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- Antibacterial and healing effect of chicha gum hydrogel (sterculia striata) with nerolidolPublication . Lima, Idglan Sá de; Ferreira, Maria Onaira Gonçalves; Barros, Esmeralda Maria Lustosa; Rizzo, Marcia dos Santos; Santos, Jailson de Araújo; Ribeiro, Alessandra Braga; Furtini, Josy Anteveli Osajima; Silva-Filho, Edson C.; Estevinho, Leticia M.Chicha gum is a natural polymer obtained from the Sterculia striata plant. The hydroxyl groups of its structure have a chemical affinity to form hydrogels, which favors the association with biologically active molecules, such as nerolidol. This association improves the biological properties and allows the material to be used in drug delivery systems. Chicha gum hydrogels associated with nerolidol were produced at two concentrations: 0.01 and 0.02 g mL−1. Then, the hydrogels were characterized by thermogravimetry (TG), Fourier Transform Infrared spectroscopy (FTIR), and rheological analysis. The antibacterial activity was tested against Staphylococcus aureus and Escherichia coli. The cytotoxicity was evaluated against Artemia salina. Finally, an in vivo healing assay was carried out. The infrared characterization indicated that interactions were formed during the gel reticulation. This implies the presence of nerolidol in the regions at 3100–3550 cm−1. The rheological properties changed with an increasing concentration of nerolidol, which resulted in less viscous materials. An antibacterial 83.6% growth inhibition effect was observed using the hydrogel with 0.02 g mL−1 nerolidol. The in vivo healing assay showed the practical activity of the hydrogels in the wound treatment, as the materials promoted efficient re-epithelialization. Therefore, it was concluded that the chicha hydrogels have the potential to be used as wound-healing products.
- Biocompatible gels of chitosan–buriti oil for potential wound healing applicationsPublication . Ferreira, Maria Onaira Gonçalves; Lima, Idglan Sá; Ribeiro, Alessandra Braga; Lobo, Anderson O.; Rizzo, Marcia S.; Osajima, Josy Anteveli; Silva-Filho, Edson C.The buriti oil (Mauritia flexuosa L.) can be associated with polymeric matrices for biomedical applications. This study aimed to evaluate the e ect of chitosan gel (CG) associated with buriti oil (CGB) as a healing agent. The fatty acids and volatile compounds composition of buriti oil were performed and the composite gels were characterized using FTIR and thermal analysis. Biological tests including antimicrobial, antioxidant, anti-inflammatory and healing e ects were also investigated. Buriti oil is composed of oleic and palmitic acids, and the main volatile compounds were identified. The buriti oil did not show antimicrobial activity, on the other hand, the composite gel (chitosan and oil) proved to be e cient against Staphylococcus aureus and Klebsiella pneumonia at the 10 mg/mL. Similar behavior was observed for antioxidant activity, determined by the -carotene bleaching assay, composite gels presenting higher activity and buriti oil showed anti-inflammatory activity, which may be related to the inhibition of the release of free radicals. Regarding wound healing performed using in vivo testing, the composite gel (CGB) was found to promote faster and complete wound retraction. The results indicated that the gel chitosan–buriti oil has a set of properties that improve its antibacterial, antioxidant and healing action, suggesting that this material can be used to treat skin lesions.
- Biopolymer from Annona muricata residues as a potential sustainable raw material for industrial applicationsPublication . Ramos, Igor F. S.; Dias, Samuel C.; Lopes, Talissa B. C.; Júnior, Francisco T. dos S. Silva; Araújo, Ricardo de; Gutierrez, Stanley J. C.; Pessoa, Claudia; Osajima, Josy A.; Rizzo, Marcia S.; Silva-Filho, Edson C.; Amorim, Manuela; Ramos, Óscar; Ribeiro, Alessandra B.; Costa, Marcilia P.Annona muricata is a fruit species belonging to the Annonaceae family, which is native to the warmer tropical areas of North and South America. A large amount of discarded residue from A. muricata is of interest for obtaining new industrial inputs. To propose the applications of the biopolymer from A. muricata residues (Biop_AmRs), this study aimed to characterize this input chemically and functionally, as well as to evaluate its potential for hemocompatibility and cytotoxicity activity in vitro. Biop_AmRs is an anionic heteropolysaccharide composed of glucose, arabinose, xylose, galactose, mannose, uronic acid, and proteins. This biopolymer exhibited a semicrystalline structure and good thermal stability. Biop_AmRs exhibited excellent water holding capacity, emulsifying properties, and mucoadhesiviness and demonstrated hemocompatibility and cytocompatibility on the L929 cell line. These results indicate possible applications for this biopolymer as a potential environmentally friendly raw material in the food, pharmaceutical, biomedical, and cosmetic industries.
- Biopolymeric materials used as nonviral vectors: a reviewPublication . Santos, Jailson de Araújo; Liarte, Daniel Barbosa; Ribeiro, Alessandra Braga; Rizzo, Marcia dos Santos; Costa, Marcília Pinheiro da; Osajima, Josy A.; Silva-Filho, Edson C.Bacterial transformation and gene transfection can be understood as being the results of introducing specific genetic material into cells, resulting in gene expression, and adding a new genetic trait to the host cell. Many studies have been carried out to investigate different types of lipids and cationic polymers as promising nonviral vectors for DNA transfer. The present study aimed to carry out a systematic review on the use of biopolymeric materials as nonviral vectors. The methodology was carried out based on searches of scientific articles and applications for patents published or deposited from 2006 to 2020 in different databases for patents (EPO, USPTO, and INPI) and articles (Scopus, Web of Science, and Scielo). The results showed that there are some deposits of patents regarding the use of chitosan as a gene carrier. The 16 analyzed articles allowed us to infer that the use of biopolymers as nonviral vectors is limited due to the low diversity of biopolymers used for these purposes. It was also observed that the use of different materials as nonviral vectors is based on chemical structure modifications of the material, mainly by the addition of cationic groups. Thus, the use of biopolymers as nonviral vectors is still limited to only a few polysaccharide types, emphasizing the need for further studies involving the use of different biopolymers in processes of gene transfer.
- Emerging applications of Sterculia striata gum in medical, pharmaceutical, and environmental fields: prospects and challengesPublication . Freitas, Alessandra Ribeiro; Ribeiro, António José; Santos, Pauline Sousa dos; Oliveira, Thaísa Cardoso de; Oliveira, Jabson Herber Profiro de; Osajima, Josy A.; Ribeiro, Alessandra Braga; Veiga, Francisco; Bezerra, Roosevelt D.S.; Silva, Albert S.; Soares-Sobrinho, José Lamartine; Muniz, Edvani Curti; Silva-Filho, Edson C.Trees of the genus Sterculia produce acidic polysaccharides with high viscosity and the ability to form gels in water. This work emphasized the species Sterculia striata and the uses of its plant derivatives, such as seeds, fruits, stem bark, and exudates. The species showed prospects for industrial application (seeds with high protein content, fruits with antioxidant potential, and stem bark with anti-inflammatory, antinociceptive, and gastroprotective potential). From a physicochemical and rheological point of view, the exudate has a high molar mass value; it contains uronic acid, galactose, rhamnose, and xylose. Sterculia striata gum (SSG) is highly viscous in solution and can form thermoreversible gels where gelation conditions depend on the purification method, acetyl groups, and presence of salt. Due to the presence of carboxylic acid groups, polyanionic behaving SSG allow the formation of polyelectrolyte complexes, which have been used in drug delivery systems (DDS) to encapsulate drugs such as antimalarial drugs, improve essential oil stability and obtain films for antimicrobial purposes. This review contributes to the understanding of the use of this biomaterial, providing a basis for new research on its different applications and industrial use, with a focus on the pharmaceutical, medical, food, and environmental fields.
- Modification of chicha gum antibacterial activity, ex vivo mucoadhesion, antioxidant activity and cellular viabilityPublication . Freitas, Alessandra R.; Ribeiro, António J.; Ribeiro, Alessandra B.; Collado-Gonzalez, Maria Del Mar; Silva, Luís R.; Alves, Luís; Melro, Elodie; Antunes, Filipe E.; Veiga, Francisco; Morais, Alan I. S.; Bezerra, Roosevelt D. S.; Soares-Sobrinho, José L.; Osajima, Josy A.; Silva-Filho, Edson C.The aim of the present work was to modify the exuded gum of Sterculia striata tree by an amination reaction. The viscosity and zero potential of the chicha gum varied as a function of pH. The modification was confirmed by X-ray diffraction (XRD), infrared spectroscopy (FTIR), size exclusion chromatography (SEC), zeta potential, thermogravimetric analysis (TG), and differential scanning calorimetry (DSC). Furthermore, the chemical modification changed the molar mass and surface charge of the chicha gum. In addition, the gums were used in tests for ex vivo mucoadhesion strength, antibacterial activity against the standard strain of Staphylococcus aureus (ATCC 25923), inhibitory activity of α-glucosidase, antioxidant capacity, and viability of Caco-2 cells. Through these tests, it was found that amination caused an increase in the mucoadhesive and inhibitory activity of chicha gum against the bacterium Staphylococcus aureus. In addition, the gums (pure and modified) showed antioxidant capacity and an inhibitory effect against the α-glucosidase enzyme and did not show cytotoxic potential.
- Modified chicha gum by acetylation for antimicrobial and antiparasitic applications: characterization and biological propertiesPublication . Braz, Elton Marks Araujo; Silva, Solranny Carla Cavalcante Costa; Brito, Carla Adriana Rodrigues Sousa; Carvalho, Fernando Aécio Amorim; Alves, Michel Muálem Moraes; Barreto, Humberto Medeiros; Silva, Durcilene Alves; Magalhães, Rui; Oliveira, Ana Leite; Silva-Filho, Edson C.It was developed a material to act as an antimicrobial and antiparasitic agent through a modification reaction in the gum structure extracted from the plant Sterculia striata. This material was characterized, the oxidant activity was evaluated and the antimicrobial activity against Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Salmonella Typhimurium and Klebsiella pneumoniae was investigated, in addition to the effect against Leishmania amazonensis, testing its acute toxicity and its cytotoxicity in human cells. Characterization techniques proved the success of chemical modification. The modification led to an increase in antioxidant activity, with excellent antibacterial activity, reaching almost 100% inhibition for P. aeruginosa and S. Typhimurium, and inhibitory effect above 70% against L. amazonensis, with an affinity far superior to the parasite than macrophages. The derivative showed no acute toxicity, it was non-hemolytic, increased cell viability in macrophages and fibroblasts, and stimulated cell proliferation of keratinocytes, thus being a strong candidate to be used as an antimicrobial and antiparasitic agent in biomedical applications.
- Phthalic anhydride esterified chicha gum: characterization and antibacterial activityPublication . Silva, Solranny Carla Cavalcante Costa; Braz, Elton Marks Araujo; Brito, Carla Adriana Rodrigues Sousa; Alves, Michel Muálem Moraes; Carvalho, Fernando Aécio Amorim; Barreto, Humberto Medeiros; Oliveira, Ana Leite; Silva, Durcilene Alves; Silva-Filho, Edson C.The objective of this research was to modify chicha gum with phthalic anhydride to obtain a new biologically active material. The chemical modification of the gum structure was proven through FTIR, elemental analysis, XRD, TG, and DSC. The derived materials demonstrated excellent inhibitory effect against P. aeruginosa and K. pneumoniae species (rating 100% inhibition) and could also inhibit Escherichia coli growth. The best antimicrobial activity observed for the derivatives suggests that chicha gum hydrophobization due to the addition of phthalic groups improved the interaction of these derivatives with bacterial cell wall components. On the other hand, the derivatives increased CC50 in macrophages but did not present acute toxicity or hemolytic activity, indicating that they are promising for use in prophylaxis or treatment of infections caused by Gram-negative bacteria.
- Potential wound healing effect of gel based on chicha gum, chitosan, and mauritia flexuosa oilPublication . Ferreira, Maria Onaira Gonçalves; Ribeiro, Alessandra Braga; Rizzo, Marcia S.; Oliveira, Antonia Carla de Jesus; Osajima, Josy Anteveli; Estevinho, Leticia M.; Silva-Filho, Edson C.Wounds are considered a clinically critical issue, and effective treatment will decrease complications, prevent chronic wound formation, and allow rapid healing. The development of products based on naturally occurring materials is an efficient approach to wound healing. Natural polysaccharides can mimic the extracellular matrix and promote cell growth, thus making them attractive for wound healing. In this context, the aim of this work was to produce a gel based on chicha gum, chitosan, and Mauritia flexuosa oil (CGCHO) for wound treatment. TG and DTG analyzed the thermal behavior of the materials, and SEM investigated the surface roughness. The percentages of total phenolic compounds, flavonoids, and antioxidants were determined, presenting a value of 81.811 ± 7.257 µmol gallic acid/g Mauritia flexuosa oil, 57.915 ± 0.305 µmol quercetin/g Mauritia flexuosa oil, and 0.379 mg/mL, respectively. The anti-inflammatory was determined, presenting a value of 10.35 ± 1.46% chicha gum, 16.86 ± 1.00% Mauritia flexuosa oil, 10.17 ± 1.05% CGCHO, and 15.53 ± 0.65% chitosan, respectively. The materials were tested against Gram-negative (Klebsiella pneumoniae) and Gram-positive (Staphylococcus aureus) bacteria and a fungus (Candida albicans). The CGCHO formulation showed better antimicrobial activity against Gram-positive bacteria. In addition, an in vivo wound healing study was also performed. After 21 days of treatment, the epidermal re-epithelialization process was observed. CGCHO showed good thermal stability and roughness that can help in cell growth and promote the tissue healing process. In addition to the good results observed for the antimicrobial, antioxidant, anti-inflammatory activities and providing wound healing, they provided the necessary support for the healing process, thus representing a new approach to the wound healing process.