The aim of this study was to evaluate the antioxidant, antibacterial, and antibiofilm activities of nerolidol. The antioxidant activity of nerolidol was determined using the total antioxidant ...activity method. Antibacterial activity was performed using the microdilution method to determine the minimum inhibitory concentration (MIC) against seven standard strains of the ATCC and four bacterial clinical isolates with a resistance profile, following the Clinical and Laboratory Standards Institute (CLSI). The antibiofilm activity of nerolidol was performed using the crystal violet method. The results of the antioxidant test revealed a total antioxidant activity of 93.94%. Nerolidol inhibited the growth of
Staphylococcus aureus
(MIC = 1 mg/mL),
Streptococcus mutans
(MIC = 4 mg/mL),
Pseudomonas aeruginosa
(MIC = 0.5 mg/mL), and
Klebsiella pneumoniae
(MIC = 0.5 mg/mL). For clinical isolates, nerolidol showed an inhibitory potential against multidrug-resistant
P. aeruginosa
,
K. pneumoniae
carbapenemase (MIC = 0.5 mg/mL), methicillin-susceptible
S. aureus
(MIC = 2 mg/mL), and methicillin-resistant
S. aureus
(MIC = 2 mg/mL). Nerolidol showed similar antibacterial activity against ATCC strains and hospital clinical isolates with resistance profile, suggesting that even though these strains are resistant to antibiotics, they are still sensitive to nerolidol. Nerolidol exerted a dose-dependent effect on the inhibition of biofilm formation, even at subinhibitory concentrations. Nerolidol inhibited bacterial biofilms of ATCC strains at a rate ranging from 51 to 98%, at concentrations ranging from 0.5 to 4 mg/mL. For clinical bacterial isolates, biofilm inhibition ranged from 6 to 60%. Therefore, the present study showed the antioxidant, antibacterial, and antibiofilm properties of nerolidol.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The present study aimed to elaborate a review of multidrug-resistant (MDR) bacteria in soil, food, aquatic environments, cattle, poultry, and swine farms in Brazil. Initially, the literature database ...for published papers from 2012 to 2023 was Scientific Electronic Library Online (SciELO), U.S. National Library of Medicine (PubMed), and Google Scholar, through the descriptors: antimicrobial resistance, resistance profile, multidrug resistance, environmental bacteria, and pathogenic bacteria. The studies demonstrated the prevalence of pathogenic and resistant bacteria in environments that favor their rapid dissemination. Bacteria of medical importance, such as
Staphylococcus aureus
,
Escherichia coli
,
Pseudomonas aeruginosa
,
Listeria monocytogenes
,
Salmonella
spp.,
Shigella
spp.,
Vibrio
spp., were present in samples from animal farms and foods, including cheese and milk, urban aquatic environments, hospital effluents, and shrimp farms. Studies suggested that important bacteria have been disseminated through different niches with easy contact with humans, animals, and food, demonstrating the danger of the emergence of increasingly difficult conditions for treating and controlling these infections. Thus, better understanding and characterizing the resistance profiles of bacteria in these regions, mainly referring to MDR bacteria, can help develop solutions to prevent the progression of this public health problem.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Morus alba L. (white mulberry) is used in traditional medicine worldwide, including Brazil. The leaves of this plant are used to treat inflammatory disorders. Universal interest in this plant ...necessitates studies on the toxicological safety and scientific substantiation of the medicinal properties of M. alba. In previous work, we investigated the acute toxicity of orally administered M. alba ethanol extract in mice.
This work was designed to investigate the ethanol extract obtained from M. alba leaves for acute toxicity when intraperitoneally administered, in vivo genotoxicity, and potential to reduce acute inflammation. In order to further investigate the constituents of the extract, we also obtained the high-performance liquid chromatography (HPLC) fingerprint of the extract.
Phytochemical analysis by thin layer chromatography (TLC) was performed and the results were used to obtain the HPLC fingerprint. Acute toxicity of 300 and 2000mg/kg b.w. i.p. doses administered to mice for 14 days was evaluated. Genotoxicity was evaluated by counting the number of micronucleated polychromatic erythrocytes in the blood of mice that either received or did not receive the extract at 75, 150 and 300mg/kg b.w. per os. The anti-inflammatory effect of the same doses administered per os was investigated using the carrageenan air pouch model.
The TLC analysis of the extract revealed the presence of a remarkable amount of flavonoids and cinnamic acids. The HPLC fingerprint showed the presence of one major peak corresponding to chlorogenic acid and two smaller peaks corresponding to flavonoids. In the toxicity assays, there were no deaths or deviations in behavior of treated mice as compared to the control at any dose. However, biochemical, hematological, and histological analyses showed that intraperitoneal injection caused several forms of damage to the mice, which were not observed in case of oral administration, studied in our previous work. Oral administration of the extract did not result in genotoxicity and considerably reduced (58.6–65.6% inhibition) leukocyte migration in all doses evaluated, in comparison with the negative control.
The ethanol extract from M. alba leaves administered intraperitoneally possesses a greater degree of toxicity in mice when compared to per os administration. The extract was not genotoxic when ingested by mice and exhibited a highly inhibitory effect against acute inflammation, which is probably linked to the presence of chlorogenic acid and flavonoids in the composition. This work contributes to the determination of safety of the medicinal use of M. alba leaves.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Despite numerous scientific advances, cancer continues to be one of the main causes of death in the world. This situation has driven the search for promising molecules. Lichen substances have been ...widely described for their pharmacological potential.
The present study evaluated the antitumour potential of a depsidone isolated from
- salazinic acid (SAL) - through
,
and
studies.
The molecule was isolated from the acetonic extract of the lichen and recrystallized in acetone. The macrophage J774, sarcoma-180 and MDA-MB-231 cell lines were used for the MTT cytotoxicity assay. The antitumor assay used a murine model (Swiss albino mice) with sarcoma-180. The animals were treated for seven consecutive days with doses of SAL (25 and 50 mg/kg) and 5-fluorouracil (20 mg/kg).
Its purity was determined using high-performance liquid chromatography (94%), and its structure was confirmed by H
and C
nuclear magnetic resonance. SAL was not considered toxic to cancer cell lines, showing cell viability rates of 79.49 ± 4.15% and 86.88 ± 1.02% for sarcoma-180 and MDA-MB-231, respectively. The tumour inhibition rate was greater than 80% in the animals treated with SAL and 65% for those that received 5-fluorouracil. Simulations of molecular dynamics to estimate the flexibility of the interactions between human thymidylate synthase and derivatives of SAL and 5-fluorouracil revealed that SAL exhibited greater enzymatic interaction capacity, with highly favourable energy, compared to 5-fluorouracil.
The present results demonstrate the potential of salazinic acid as a tumour inhibition agent.
Himatanthus drasticus is a tree popularly known as janaguba. Endemic to Brazil, it is found in the Cerrado and Caatinga biomes, rock fields, and rainforests. Janaguba latex has been used in folk ...medicine for its antineoplastic, anti-inflammatory, analgesic, and antiallergic activities. However, studies investigating the safety of its use for medicinal purposes are limited.
Aim of the study: This study aimed to evaluate the toxicity of the latex extracted from H. drasticus.
The latex was extracted from H. drasticus specimens by removing a small area of bark (5 × 30 cm) and then dissolving the exudate in water and lyophilizing it. Phytochemical screening was performed by TLC and GC-MS, protein, and carbohydrate levels. Cell viability was performed by the MTT method. Acute oral toxicity, genotoxicity, and mutagenicity assays were performed in mice.
TLC showed the presence of saponins and reducing sugars, as well as steroids and terpenes. The GC-MS analysis of the nonpolar fraction identified lupeol acetate, betulin, and α/β-amyrin derivatives as the major compounds. The latex was toxic to S-180 cells at 50 and 100 μg/mL. No signals of toxicity or mutagenicity was found in mice treated with 2000 mg/kg of the latex, but genotoxicity was observed in the Comet assay.
H. drasticus latex showed toxicity signals at high doses (2000 mg/kg). Although the latex was not mutagenic to mice, it was genotoxic in the Comet assay in our experimental conditions. Even testing a limit dose of 2000 mg/kg, which is between 10 to 35-fold the amount used in folk medicine, caution must be taken since there is no safe level for genotoxic compounds exposure. Further studies on the toxicological aspects of H. drasticus latex are necessary to elucidate its possible mechanisms of genotoxicity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The fibrinolytic enzyme produced by Mucor subtilissimus UCP 1262 was obtained by solid fermentation and purified by ion exchange chromatography using DEAE-Sephadex A50. The enzyme toxicity was ...evaluated using mammalian cell lineages: HEK-293, J774.A1, Sarcoma-180 and PBMCs which appeared to be viable at a level of 80%. The biochemical parameters of the mice treated with an acute dose of enzyme (2000 mg/mL) identified alterations of AST and ALT and the histomorphometric analysis of the liver showed a loss of endothelial cells (P < 0.001). However, these changes are considered minimal to affirm that there was a significant degree of hepatotoxicity. The comet assay and the micronucleus test did not identify damage in the DNA of the erythrocytes of the animals treated. The protease did not degrade the Aα and Bβ chains of human and bovine fibrinogens, thus indicating that it does not act as anticoagulant, but rather as a fibrinolytic agent. The assay performed to assess blood biocompatibility shows that at dose of 0.3–5 mg/mL the hemolytic grade is considered insignificant. Moreover, the enzyme did not prolong bleeding time in mice when dosed with 1 mg/kg. These results indicate that this enzyme produced is a potential competitor for developing novel antithrombotic drugs.
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•The enzyme toxicity was investigated.•This protease has to hemostatic safety compared to other anticoagulant agents.•Appears to be a direct acting fibrinolytic agent.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The objective of this study was to determine the cytotoxicity of organic extracts of P. moniliformis in vitro and identify the acute toxicity and genotoxicity in vivo. The leaves were extracted using ...three organic solvents (cyclohexane EP1, ethyl acetate EP2, and methanol EP3). Phytochemical qualitative analysis was performed by thin layer chromatography (TLC). Cytotoxicity tests were performed on human embryonic kidney (HEK) cells and J774 murine macrophages. Acute toxicity in mice was measured after intraperitoneal (ip) administration of 2000 mg/kg, while evaluation of genotoxicity and mutagenicity were assessed using the comet assay and the micronucleus (MN) test, respectively. The TLC analysis of the extracts revealed the presence of flavonoids, triterpenes, steroids, and saponins. In the cytotoxicity assay, extracts EP1 and EP3 altered proliferation of HEK cells, and all organic extracts increased the viability of J774 cells. In the toxicity tests, no deaths or behavioral alterations were observed in mice exposed to the acute dose of the extracts. Although some extracts led to changes in hematological and histological parameters, these results did not indicate physiological changes. In relation to the MN test and comet assay, no significant changes were detected in the DNA of the animals tested with the extracts EP1, EP2, and EP3. Thus, extracts of P. moniliformis were not considered to be toxic and did not induce formation of MN or damage to cellular DNA in the genotoxicity tests.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Coalho cheese is a dairy product typical of the Northeast region of Brazil and widely consumed by the population; however, the poor quality of the raw material used in association with the absence of ...standardization in the manufacturing process makes it susceptible to microbial contamination, mainly by Staphylococcus aureus. The objective of this study was to evaluate the influence of chitosan as a coating and incorporated in coalho cheese on S. aureus viability and the sensorial acceptance of the cheese. For this, coalho cheeses were made with chitosan in the coating or added to the curds at 5 mg mL-1, 10 mg mL-1 and 15 mg mL-1 and 1 mg g-1, 2 mg g-1 and 4 mg g-1, respectively. Products without chitosan (C) and 1% acetic acid (CA) were used as controls. The bacterial inhibition of chitosan in the artificially contaminated samples was assessed by comparing the viable cell count of S. aureus (ATCC 6538) in each treatment over five time intervals (0, 4, 8, 12 and 16 d storage). Product C was evaluated for moisture and fat content. The sensorial and shelf stability analyses were performed with the control and chitosan treated samples at the most efficient antibacterial concentrations. The sensorial analyses were performed with 100 consumers. Chitosan antimicrobial activity was observed in all treatments; however, the highest concentrations of chitosan added as a coating and to the cheese, 15 mg mL-1 and 4 mg g-1, respectively, inhibited S. aureus. The moisture and fat contents met the standards established by the Brazilian legislation. Regarding stability, the samples complied with the regulatory microbiological limits and presented acceptable pH, acidity and water activity values. As far as sensorial acceptance was concerned, the scores corresponded to hedonic concepts between "I liked it slightly" and "I liked it a lot", with an improvement in the texture of the products when chitosan was incorporated. Acceptability values were higher than 70%, except for the taste the products with chitosan covering them, which was 68.3%. It can be inferred from the results that the use of chitosan as a coating and incorporated in coalho cheese is a favourable alternative for the preservation of this product and has potential commercial applicability.
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