Pedro Marinho

Mr. Pedro Marinho


Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 October 2024 in Pharmaceutics
Verified
Journal Article
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MAMaria Lorena de Oliveira Andrade
Maria Lorena de Oliveira Andrade
PMPedro Marinho
Pedro Marinho
AOAlisson Macário de Oliveira
Alisson Macário de Oliveira
TSThalisson Souza
Thalisson Souza
SCSamuel Cibulski
Samuel Cibulski
HAHarley Alves
Harley Alves
Background/objectives: Apodanthera glaziovii is an endemic species from the semi-arid Brazilian, which has limited toxicological and pharmacological studies. This species belongs to a well-studied family known for its bioactive compounds used in treating inflammatory. This study aimed to identify secondary metabolites in the stems from A. glaziovii, evaluate toxicity, and investigate the anti-inflammatory potential of the stem hydroalcoholic extract (SHE-Ag). Methods: qualitative and quantitative assays were employed to identify secondary metabolites, along with chromatographic analyses and 1H and 13C NMR. Toxicity was assessed through in vitro hemolytic toxicity, in vivo genotoxicity, and oral acute toxicity tests before the pharmacological assays were conducted. Results: phytochemical screening, HPLC and NMR analyses suggested the presence of saponins of the norcucurbitacin class. The SHE-Ag exhibited no hemolytic activity and no mutagenic potential. However, in vivo toxicity at a dose of 2000 mg/kg revealed hematological and biochemical alterations, while the 500 mg/kg dose was safe. In the anti-inflammatory assays, SHE-Ag at 100 mg/kg reduced paw edema by 55.8%, and leukocyte and neutrophil migration by 62% and 68% in the peritonitis model, respectively; inflammatory cell migration by 70% in the air pouch model, outperforming indomethacin, which showed a 54% reduction. Conclusions: these findings indicate that SHE-Ag is rich in saponins, confirmed through HPLC and 1H and 13C NMR analyses. The SHE-Ag also demonstrated low toxicity. The inflammation models used showed a reduction in inflammation, pro-inflammatory cells, and edema, highlighting the significant anti-inflammatory activity of hydroethanolic extract A. glaziovii stems.

27 November 2025 in Plants
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Journal Article
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KAKailane Lourenço Araújo
Kailane Lourenço Araújo
NLNatanael Teles Ramos de Lima
Natanael Teles Ramos de Lima
PMPedro Marinho
Pedro Marinho
DGDara Rayanne da Silva Guedes
Dara Rayanne da Silva Guedes
MSMarcelo Silva
Marcelo Silva
AOAlisson Macário de Oliveira
Alisson Macário de Oliveira
Calotropis procera, known as “Silk cotton”, stands out for the presence of various classes of bioactive compounds responsible for its ethnopharmacological properties. The study aimed to conduct a phytochemical investigation, evaluating the in vitro and in vivo toxicity together with the antinociceptive potential of an n-butanolic fraction (FB) from the leaves. The crude ethanolic extract (CEE) was obtained by maceration in ethanol for 72 h. It was then partitioned using a gradual solvent sequence. The FB was analyzed by HPLC-ESI-MS/MS in negative mode and 1H and 13C NMR. Toxicity was assessed by the erythrocyte hemolytic assay and acute oral toxicity test at a single dose of 300 mg·kg−1. The antinociceptive effect was assessed by the acetic acid-induced abdominal writhing test and the formalin test in mice at doses of 3.75, 7.5 and 15 mg·kg−1 per os. HPLC-ESI-MS/MS analysis identified flavonoids, phenolic acids, and the megastigmane roseoside, isolated for the first time in C. procera. The FB did not cause hemolytic effects or behavioral or physiological changes in mice. It showed an antinociceptive effect at all doses, reducing abdominal writhing by up to 91.46% and the licking time in phases 1 and 2 of the formalin test by up to 63.83% and 91.73%, respectively. In this study, it was possible to determine that an FB of a crude extract of C. procera leaves has antinociceptive activity, possibly associated with the phenolic compounds and roseoside found, with a lack of toxicity in vitro and in vivo, validating its ethnopharmacological use.

18 October 2025 in Drugs and Drug Candidates
Verified
Journal Article
Open access
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PMPedro Marinho
Pedro Marinho
WCWêndeo Kennedy Costa
Wêndeo Kennedy Costa
MCMaria Tereza dos Santos Correia
Maria Tereza dos Santos Correia
WSWliana Alves Viturino da Silva
Wliana Alves Viturino da Silva
MFMágda Ferreira
Mágda Ferreira
AOAlisson Macário de Oliveira
Alisson Macário de Oliveira
Background/Objectives: This study investigated the flavonoid enrichment and antimicrobial activity of the ethyl acetate fraction (EAF) obtained from Croton blanchetianus (Euphorbiaceae) leaves against Staphylococcus aureus, including the methicillin-resistant strains (MRSA) that were isolated, as well as its possible mechanism of action. Methods: Croton blanchetianus leaves were extracted with ethanol:water (50%), then the extract was spray-dried and partitioned (8×) with ethyl acetate. Phytochemical analysis was performed using thin layer chromatography (TLC), while antibacterial activity was conducted using minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methods. Results: Chemical profiling (TLC) confirmed multiple flavonoid bands and the presence of hyperoside; the total flavonoid content in the EAF reached 25.3% (≈2.28× the spray-dried extract and 6.65× the aqueous fraction). The MIC and MBC assays against S. aureus ATCC 29213 and six clinical isolates showed an MIC of 4–32 μg/mL and an MBC of 16–64 μg/mL for EAF. The combination of EAF with chloramphenicol showed a complete synergistic effect for S. aureus ATCC 29213 and S. aureus UFPEDA 705, a partial effect for S. aureus UFPEDA-659 and S. aureus UFPEDA-671, antagonistic effect for S. aureus UFPEDA 731 and S. aureus UFPEDA 802, and no effect for S. aureus UFPEDA-691. Growth curves indicated time- and concentration-dependent inhibition. Membrane integrity assays revealed K+ efflux and release of DNA/RNA and proteins, suggesting bacterial membrane destabilization as a likely mechanism. Conclusions: The flavonoid-rich fraction of C. blanchetianus exhibits potent anti-S. aureus activity, including MRSA. Furthermore, it was observed that EAF has a synergistic effect with chloramphenicol and acts through membrane damage, making it a candidate for a phytoderived adjuvant in antimicrobial therapies.