Development of gel containing Psidium glaziovianum essential oil has in vitro antimicrobial activity and improves healing of excisional wounds in mice.

Wounds encompass physical, chemical, biological, induced damages to the skin or mucous membranes. In wound treatment, combating infections is a critical challenge due to their potential to impede recovery and inflict systemic harm on patients. Previously, the essential oil extracted from Psidium glaziovianum (PgEO) demonstrated antinociceptive and anti-inflammatory attributes, along with negligible oral toxicity. Hence, our study aimed to assess the effects of topically applying a gel formulation containing PgEO to excisional wounds in mice. Additionally, an in vitro antimicrobial assessment was conducted. The formulated gel underwent characterization and toxicological evaluation on erythrocytes, as well as a dermal irritation test. Its antimicrobial activity was tested against both gram-positive and gram-negative bacteria, as well as fungi. Subsequently, an assessment of its efficacy in excisional wound healing was conducted in mice. The findings of this investigation highlight the gel's efficacy against both gram-positive and gram-negative bacteria, as well as fungi. Moreover, this study underscores that the PgEO-gel treatment enhances skin wound healing, potentially due to its capacity to trigger antioxidant enzymes and suppress pro-inflammatory cytokines. Furthermore, the gel exhibited minimal toxicity to erythrocytes and skin irritation. These findings hold promise for prospective preclinical and clinical trials across diverse wound types. In conclusion, this study sheds light on the potential therapeutic applications of the gel formulation containing essential oil from P. glaziovianum in the context of wound healing.

In vitro evaluation of alkaline lignins as antiparasitic agents and their use as an excipient in the release of benznidazole.

The Amazon rainforest is considered the largest tropical timber reserve in the world. The management of native forests in the Amazon is one of the most sensitive geopolitical issues today, given its national and international dimension. In this work, we obtained and characterized physicochemical lignins extracted from branches and leaves of Protium puncticulatum and Scleronema micranthum. In addition, we evaluated in vitro its potential as an antioxidant, cytotoxic agent against animal cells and antiparasitic against promastigotes of Leishmania amazonensis, trypomastigotes of T. cruzi and against Plasmodium falciparum parasites sensitive and resistant to chloroquine. The results showed that the lignins obtained are of the GSH type and have higher levels of guaiacyl units. However, they show structural differences as shown by spectroscopic analysis and radar charts. As for biological activities, they showed antioxidant potential and low cytotoxicity against animal cells. Antileishmanial/trypanocidal assays have shown that lignins can inhibit the growth of promastigotes and trypomastigotes in vitro. The lignins in this study showed low anti-Plasmodium falciparum activity against susceptible strains of Plasmodium falciparum and were able to inhibit the growth of the chloroquine-resistant strain. And were not able to inhibit the growth of Schistosoma mansoni parasites. Finally, lignins proved to be promising excipients in the release of benznidazole. These findings show the potential of these lignins not yet studied to promote different biological activities.

Lignin from Morinda citrifolia leaves: Physical and chemical characterization, in vitro evaluation of antioxidant, cytotoxic, antiparasitic and ultrastructural activities.

In this work, we investigated in vitro the antioxidant, cytotoxic and anti-leishmanial activities of a lignin extracted from the leaves of Morinda citrifolia. Initially, an analysis of the composition of the sheets was performed, then the lignin was obtained by alkaline delignification and characterized by different techniques: elemental analysis, FT-R, UV-vis, HSQC-NMR, thermal analysis, Py-GC/MS and by GPC. The results showed that the leaves had in their composition cellulose (31.29%), hemicellulose (25.01%), lignin (18.34%), extractives (14.39%) and ash (10.03%). The lignin extraction yield was 89.8%. The lignin obtained is of the GSH type with the following contents 79.39%, 13.58% and 7.03% respectively. Furthermore, it is low molecular weight and thermally stable. It had a phenolic content of 93.3 mg GAE/g and low antioxidant activity. In macrophage cytotoxicity assays, it presented a CC50 of 31.0 µg/mL, showing less toxicity than amphotericin B. In assays against the promastigote forms of Leishmania amazonensis, lignin presented an IC50 of 29.56 µg/mL, a less effective concentration than amphotericin B (IC50 = 0.14 µg/mL). However, it was able to promote inhibition of the parasites, a fact confirmed by structural changes. These findings reinforce that M. citrifolia lignin is a promising macromolecule for use as an antiparasitic and antioxidant agent.

Novel indol-3-yl-thiosemicarbazone derivatives: Obtaining, evaluation of in vitro leishmanicidal activity and ultrastructural studies.

Parasitic diseases still represent serious public health problems, since the high and steady emergence of resistant strains is evident. Because parasitic infections are distributed predominantly in developing countries, less toxic, more efficient, safer and more accessible drugs have become desirable in the treatment of the infected population. This is the case of leishmaniasis, an infectious disease caused by a protozoan of the genus Leishmania sp., responsible for triggering pathological processes from the simplest to the most severe forms leading to high rates of morbidity and mortality throughout the world. In the search for new leishmanicidal drugs, the thiosemicarbazones and the indole fragments have been identified as promising structures for leishmanicidal activity. The present study proposes the synthesis and structural characterization of new indole-thiosemicarbazone derivatives (2a-j), in addition to performing in vitro evaluations through cytotoxicity assays using macrophages (J774) activity against forms of Leishmania infantum and Leishmania amazonensis promastigote as well as ultrastructural analyzes in promastigotes of L. infantum. Results show that the indole-thiosemicarbazone derivatives were obtained with yield values varying from 32.09 to 94.64%. In the evaluation of cytotoxicity, the indole-thiosemicarbazone compounds presented CC50 values between 53.23 and 357.97 µM. Concerning the evaluation against L. amazonensis promastigote forms, IC50 values ranged between 12.31 and  > 481.52 µM, while the activity against L. infantum promastigotes obtained IC50 values between 4.36 and 23.35 µM. The compounds 2d and 2i tested against L. infantum were the most promising in the series, as they showed the lowest IC50 values: 5.60 and 4.36 respectively. The parasites treated with the compounds 2d and 2i showed several structural alterations, such as shrinkage of the cell body, shortening and loss of the flagellum, intense mitochondrial swelling and vacuolization of the cytoplasm leading the parasite to cellular unviability. Therefore, the indole-thiosemicarbazone compounds are promising because they yield considerable synthesis, have low cytotoxicity to mammalian cells and act as leishmanicidal agents.

Comparison of smear layer removal using the Nd:YAG laser, ultrasound, ProTaper Universal system, and CanalBrush methods: an in vitro study.

INTRODUCTION: The aim of this study was to compare the efficacy of the Nd:YAG laser, ultrasound, the ProTaper Universal system (Dentsply Maillefer, Ballaigues, Switzerland), and the CanalBrush (Coltene Whaledent, Langenau, Germany) methods for the removal of the smear layer from the apical third of root canals. METHODS: Fifty distal root canals from extracted human mandibular first molars were instrumented up to ProTaper Universal F5 and divided randomly into 5 groups (n = 10) according to the following final irrigation agitation techniques: no agitation (control), ProTaper Universal file, ultrasound, CanalBrush, and Nd:YAG laser. Specimens were observed under a scanning electron microscope. The presence of the smear layer was evaluated using a 3-grade scoring system. The data were analyzed with Cohen kappa, Kruskal-Wallis, and Mann-Whitney U tests. A level of significance of .05 was adopted. RESULTS: The ultrasound group performed significantly better than the rest of the groups; 56.6% of the specimens revealed no smear layer, 44.4% showed the presence of a moderate smear layer, and no heavy smear layers were observed. In the Nd:YAG laser group, 30% of the specimens presented with no smear layer, 70% showed the presence of a moderate smear layer, and no heavy smear layers were observed. In contrast, a heavy smear layer was observed on the surfaces of the root canals in the CanalBrush (23.4%), ProTaper Universal (13.4%), and control (86.6%) groups. Statistically significant differences were observed (P < .05). CONCLUSIONS: None of the agitation methods completely removed the smear layer. However, the ultrasound method performed significantly better followed by the Nd:YAG laser, the CanalBrush, and the ProTaper Universal system. Agitation of the irrigant improved smear layer removal in the apical third of the canal.

Improved microwave-mediated synthesis of 3-(3-aryl-1,2,4-oxadiazol-5-yl)propionic acids and their larvicidal and fungal growth inhibitory properties.

The synthesis of 3-(3-aryl-1,2,4-oxadiazol-5-yl)propionic acids from arylamidoximes and succinic anhydride under focused microwave irradiation conditions is described. The new synthetic method furnished the desired products in 2-3 min and good yields. Furthermore, the previously complicated purification procedure has been simplified in a manner which is quick, eco-friendly and cost-effective. Larvicidal bioassay and fungal growth inhibitory tests were performed using several 3-(3-aryl-1,2,4-oxadiazol-5-yl)propionic acids. These acids presented strong larvicidal activity against L4 larvae of Aedes aegypti. The results suggest that larvicidal activity might be correlated with the presence of electron-withdrawing substituents in the para position of the phenyl ring except the fluorine atom. The alterations observed in the larvae spiracular valves of the siphon and anal papillae by 1,2,4-oxadiazoles in the larvicidal bioassay are responsible for larvae's death. Furthermore, all acids inhibited the fungal growth of five different types of fungi, viz., Fusarium solani, F. oxysporum, F. moniliforme, F. decemcellulare and F. lateritium in a preliminary evaluation. Both of these activities are being disclosed for the first time for 1,2,4-oxadiazole-5-yl ring linked at C-3 of propionic acid.