Dermatophyte species infect the epidermis and appendages, often with serious social and health-economic consequences. The hydroalcoholic extract of pomegranate fruit peel showed activity against the ...dermatophyte fungi Trichophyton mentagrophytes, T. rubrum, Microsporum canis and M. gypseum.
Hydroalcoholic extract was prepared with pomegranate peels. This crude extract was fractionated and submitted to liquid-liquid partition, resulting in an active fraction which was fractionated in a Sephadex LH-20 column, followed by a Lobar column. The structure of the active compound was established with the use of spectroscopic methods.
The crude extract of pomegranate fruit peel showed activity against the dermatophytes Trichophyton mentagrophytes, T. rubrum, Microsporum canis, and M. gypseum, with MICs values of 125 μg/ml and 250 μg/ml, respectively for each genus. Punicalagin was isolated and identified by spectroscopic analysis. The crude extract and punicalagin showed activity against the conidial and hyphal stages of the fungi. The cytotoxicity assay showed selectivity for fungal cells than for mammalian cells.
These results indicated that the crude extract and punicalagin had a greater antifungal activity against T. rubrum, indicating that the pomegranate is a good target for study to obtain a new antidermatophyte medicine.
The genus Alicyclobacillus spp. can deteriorate foods with low pH, such as citrus juices, changing their odor and taste. Different studies seek an alternative for the control of this microorganism in ...orange juice, and the antibacterial effect of papain and bromelain proteases has already been demonstrated under these conditions. However, one of the limitations of the application of these compounds is the drastic decrease of the antibacterial action when the product is subjected to high temperatures, such as pasteurization. The objective of the present study was to microencapsulate these enzymes with alginate and chitosan and evaluate their action following thermal processes. Microencapsulation was performed by spray drying and the compounds were subjected to high temperatures. Their inhibitory and bactericidal activity against five different species of Alicyclobacillus was then evaluated. The microcapsules were characterized by Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC) and Infrared Spectroscopy (FT-IR). The microencapsulation of the particles was evidenced. The results showed that papain microencapsulated with chitosan or alginate maintained low minimum inhibitory concentration values after submission to heat treatment, demonstrating its effectiveness and potential application as a biopreservative.
•Microencapsulation of papain and bromelain with polymers was performed.•The microcapsules showed antibacterial activity against Alicyclobacillus spp.•Microencapsulation of papain maintained antibacterial action after heat treatment.•Microencapsulated papain showed potential application as a bioconservative.
Phytochemical investigation of Chromolaena laevigata led to the isolation of a new cadinene-sesquiterpene, chromolaevigone glucoside (1), along with nine known compounds: daucosterol (2), ...stigmasterol glycoside (3), stigmasterol (4), β-sitosterol (5), pilloin (6), gonzalitosin I (7), quercetin-3-O-α-rhamnopyranoside (8), 7,7-dihydroxy-calamen-12-oic acid lactone (9) and trachelanthic acid (10). Others 11 known compounds were identified by UHPLC-HRMS/MS. These compounds are being described for the first time in this species, with the exception of cadinene 9. Furthermore, due to the limitation of pharmacological studies, antiproliferative, antiviral, and antimicrobial activities of C. laevigata were evaluated. The best results in the cytotoxicity, antimicrobial and antiproliferative tests, presenting GI
50
values on ovarian tumour cells (OVCAR-03) of 1.9 μg mL
−1
and kidney (786-0) of 2.5 μg mL
−1
were observed for the hexanic fraction.
Statement of problem The influence of different joining techniques on passive fit at the interface structure/abutment of cobalt-chromium (Co-Cr) superstructures has not yet been clearly established. ...Purpose The purpose of this study was to compare 3 different techniques of joining Co-Cr superstructures by measuring the resulting marginal misfit in a simulated prosthetic assembly. Material and methods A specially designed metal model was used for casting, sectioning, joining, and measuring marginal misfit. Forty-five cast bar-type superstructures were fabricated in a Co-Cr alloy and randomly assigned by drawing lots to 3 groups (n=15) according to the joining method used: conventional gas-torch brazing (G-TB), laser welding (LW), and tungsten inert gas welding (TIG). Joined specimens were assembled onto abutment analogs in the metal model with the 1-screw method. The resulting marginal misfit was measured with scanning electron microscopy (SEM) at 3 different points: distal (D), central (C), and mesial (M) along the buccal aspect of both abutments: A (tightened) and B (without screw). The Levene test was used to evaluate variance homogeneity and then the Welsch ANOVA for heteroscedastic data (α=.05). Results Significant differences were found on abutment A between groups G-TB and LW ( P =.013) measured mesially and between groups G-TB and TIG ( P =.037) measured centrally. On abutment B, significant differences were found between groups G-TB and LW ( P <.001) and groups LW and TIG (P<.001) measured mesially; groups G-TB and TIG ( P =.007) measured distally; and groups G-TB and TIG ( P =.001) and LW and TIG ( P =.007) measured centrally. Conclusions The method used for joining Co-Cr prosthetic structures had an influence on the level of resulting passive fit. Structures joined by the tungsten inert gas method produced better mean results than did the brazing or laser method.
Endophytes are microorganisms that form symbiotic relationships with their host. These microorganisms can produce a variety of secondary metabolites, some of which have inhibitory effects on pests ...and pathogens or even act to promote plant growth. Due to these characteristics, these microorganisms are used as sources of biologically active substances for a wide range of biotechnological applications. Based on that, the aim of this study was to evaluate the production of metabolites of the endophytic
Aspergillus flavus
CL7 isolated from
Chromolaena laevigata
, in four different cultivation conditions, and to determine the antimicrobial, cytotoxic, antiviral, and antioxidant potential of these extracts. The multiphasic approach used to identify this strain was based on morphology and ITS gene sequence analysis. The chemical investigation of
A. flavus
using potato dextrose and minimal medium, using both stationary and agitated methods, resulted in the isolation of kojic acid, α-cyclopiazonic acid, and 20,25-dihydroxyaflavinine. Another 18 compounds in these extracts were identified by UHPLC-HRMS/MS, of which dideacetyl parasiticolide A has been described for the first time from
A. flavus
. Aflatoxins, important chemomarkers of
A. flavus
, were not detected in any of the extracts, thus indicating that the CL7 strain is non-aflatoxigenic. The biological potential of all extracts was evaluated, and the best results were observed for the extract obtained using minimal medium against
Trichophyton rubrum
and
Mycobacterium tuberculosis
.
The phytochemical investigation of Grazielia gaudichaudeana aerial parts yielded 15 compounds, including diterpenes, triterpenes, sterols and flavonoids. With exception to ent‐kaurenoic acid ...diterpenes, the compounds isolated are being described for the first time in this species. Some unusual 1H‐NMR chemical shifts of 18‐nor‐ent‐labdane (7–9) led us carry out a conformational analysis by theoretical calculations in order to support the experimental data. Moreover, due to the limitation of studies focused on pharmacological potential of Grazielia gaudichaudeana, the present study was carried out to investigate the antioxidant, antiproliferative, antiviral, antileishmanial and antimicrobial activities from the extract, fractions and isolated compounds obtained from this species. Ethyl acetate fraction showed significant activity in the antiproliferative assay, with GI50 range of 3.9 to 27.2 μg mL−1. Dichloromethane fraction, rich in diterpenoids, inhibited all human tumor cell lines tested, and the nor‐labdane 7 showed potent cytotoxic activity against glioma and ovary cancer cell lines.
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Many infections worldwide are associated with bacterial biofilms. The effects of isolated neolignans (conocarpan and eupomathenoid-5) and the dichloromethane extract of Piper ...regnellii (Miq.) C. DC., Piperaceae, were tested against isolates of methicillin-resistant Staphylococcus aureus and methicillin-sensitive S. aureus biofilms and S. aureus planktonic cells. The dichloromethane extract presented better results than isolated neolignans against all of the biofilms tested, with a minimum inhibitory concentration <400μg/ml for preformed biofilms and minimal biofilm inhibitory concentration of 15.6μg/ml for biofilm formation. The minimum inhibitory concentration to planktonic cells was <12.5μg/ml. These results indicate a good effect of the dichloromethane extract against methicillin-resistant S. aureus and methicillin-sensitive S. aureus biofilms and efficient prophylaxis.
Copaiba oil, an oleoresin extracted from Copaifera genus, has been widely used in popular medicine for the treatment of several diseases. The aim of this study was to investigate the antifungal ...activity of the copaiba oil and its isolated compounds caryophyllene oxide, copalic acid and acetoxycopalic acid against Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum gypseum strains, using microdilution method and microscopy techniques. It was found that the copaiba oil and the copalic acid were active against dermatophytes by minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) tests. The MIC and MFC of copaiba oil against T. rubrum, T. mentagrophytes and M. gypseum were 125 µg mL-1 (250 µg mL-1), 500 µg mL-1 (500 µg mL-1) and 250 µg mL-1 (250 µg mL-1), respectively. For copalic acid, the MIC and MFC were 50 µg mL-1 (100 µg mL-1), 100 µg mL-1 (100 µg mL-1) and 50 µg mL-1 (100 µg mL-1), respectively. Fluorescence microscopy and scanning electronic microscopy were used to investigate inhibition on hyphal growth by compounds, copaiba oil and copalic acid, showing a strong inhibition and an irregular growth pattern. Cell wall, cytoplasmic membrane and intracellular contents were also damaged. In conclusion, copaiba oil and copalic acid showed great activity against dermatophytes, being potential compounds for the development of antifungal drugs.
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