Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
Add more filters










Publication year range
1.
Braz J Microbiol ; 54(4): 2651-2661, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37642890

ABSTRACT

Endophytic fungi produce a range of known metabolites and several others, not yet explored, which present important biological activities from the pharmaceutical and industrial perspective. Several studies have reported the diversity of endophytes in Coffea arabica plants, although few have been described in organic cultures. In the current paper, we describe the chemical profile of specialized metabolites in the ethyl acetate phase in a strain of the endophytic fungus Colletotrichum siamense associated with coffee (Coffea arabica L.) (Rubiaceae) and its potential against tumor cells and bacteria of medical and food importance. Cytotoxicity assays in tumor cells MCF-7 and HepG2/C3A were performed by MTT and microdilution in broth to evaluate the antibacterial action of metabolic extract. The antiproliferative assay showed promising results after 24 h of treatment, with 50% injunction concentrations for the two cell types. UHPLC-MS/MS analyses with an electrospray ionization source were used to analyze the extracts and identify compounds of species Colletotrichum siamense, which is still little explored as a source of active metabolites. Many of these compounds observed in the endophytic need to be chemically synthesized in industry, at high costs, while production by the fungus becomes a chemically and economically more viable alternative. Pyrocatechol, gentisyl alcohol, and alpha-linolenic acid, associated with different mechanisms of action against tumor cells, were detected among the main compounds. The extract of the endophytic fungus Colletotrichum siamense presented several compounds with pharmacological potential and antibacterial activity, corroborating its potential in biotechnological applications.


Subject(s)
Coffea , Colletotrichum , Coffea/microbiology , Coffee/metabolism , Tandem Mass Spectrometry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/metabolism , Plant Extracts/pharmacology , Plant Extracts/metabolism , Endophytes
2.
J Food Sci Technol ; 60(9): 2477-2485, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37424585

ABSTRACT

This study evaluated the antibacterial activity of cinnamaldehyde (CIN) and biogenic silver nanoparticles (BioAgNP), alone and in combination, against Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus in vitro. Their sanitation activities on fresh sweet grape tomatoes were also evaluated. CIN and BioAgNP inhibited the growth of the tested bacteria, and at low concentrations, their combinations presented a synergistic effect. In the sanitization of fresh sweet grape tomatoes, CIN (156 µg/mL) combined with BioAgNP (31.25 µM) at subinhibitory concentrations inhibited the growth of E. coli after only 5 min of contact. Exposed samples showed no growth of E. coli during their shelf life. The combination of these compounds did not change significantly (p > 0.05) the physicochemical properties of sweet grape tomatoes and showed that CIN combined with BioAgNP could represent an effective method for decontaminating fruits and vegetables. This combination has great potential for application in the prevention of foodborne diseases.

3.
J Food Sci Technol ; 60(2): 581-589, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36712216

ABSTRACT

Nisin, a bacteriocin widely used in the food industry, and curcumin, the yellow pigment extracted from turmeric (Curcuma longa L.) stand out among the numerous natural preservatives that have antimicrobial activity. The conversion of these compounds into nanoparticles could be interesting as an alternative to improve technological aspects (such as the low water solubility of curcumin) and to evaluate how synergism could take place in the case of co-encapsulation. The main objective of the present work was to evaluate the combination of nisin (Nis) with nanoencapsulated curcumin (NCur, nanoencapsulated to promote water solubility), as well as the co-encapsulated curcumin and nisin (NCurNis), against the foodborne bacteria Staphylococcus aureus, Escherichia coli and Salmonella Typhimurium. Minimum inhibitory concentration and the minimum bactericidal concentration were evaluated for NCur and Nis, as well as their combination with the fractional inhibitory concentration assay. High effectiveness was found against S. aureus and the combination of both compounds resulted in Nis- nisin; synergism against the same microorganism. The co-encapsulation of curcumin and nisin was carried out based on the synergism tests and the characterization analyses demonstrated that a solid dispersion of the components in the PVP matrix was formed. The inhibitory effect of the curcumin and nisin co-encapsulate was improved when compared to the curcumin nanoparticles or nisin alone. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05641-8.

4.
Photochem Photobiol ; 99(3): 957-966, 2023.
Article in English | MEDLINE | ID: mdl-36054748

ABSTRACT

In order, understanding the antimicrobial action of photodynamic therapy and how this technique can contribute to its application in the control of pathogens. The objective of the study was to employ a proteomic approach to investigate the protein profile of Staphylococcus aureus after antimicrobial photodynamic therapy mediated by rose bengal (RB-aPDT). S. aureus was treated with RB (10 nmoL L-1 ) and illuminated with green LED (0.17 J cm-2 ) for cell viability evaluation. Afterward, proteomic analysis was employed for protein identification and bioinformatic tools to classify the differentially expressed proteins. The reduction in S. aureus after photoinactivation was ~2.5 log CFU mL-1 . A total of 12 proteins (four up-regulated and eight down-regulated) correspond exclusively to alteration by RB-aPDT. Functionally, these proteins are distributed in protein binding, structural constituent of ribosome, proton transmembrane transporter activity and ATPase activity. The effects of photodamage include alterations of levels of several proteins resulting in an activated stress response, altered membrane potential and effects on energy metabolism. These 12 proteins required the presence of both light and RB suggesting a unique response to photodynamic effects. The information about this technique contributes valuable insights into bacterial mechanisms and the mode of action of photodynamic therapy.


Subject(s)
Anti-Infective Agents , Photochemotherapy , Staphylococcus aureus , Rose Bengal/pharmacology , Photosensitizing Agents/pharmacology , Photosensitizing Agents/chemistry , Proteomics , Photochemotherapy/methods , Anti-Infective Agents/pharmacology
5.
Carbohydr Polym ; 248: 116832, 2020 Nov 15.
Article in English | MEDLINE | ID: mdl-32919546

ABSTRACT

Generally, the selection of fructans prebiotics and probiotics for the formulation of a symbiotic has been based on arbitrary considerations and in vitro tests that fail to take into account competitiveness and other interactions with autochthonous members of the intestinal microbiota. However, such analyzes may be a valuable step in the development of the symbiotic. The present study, therefore, aims to investigate the effect of lactobacilli strains and fructans (prebiotic compounds) on the growth of the intestinal competitor Klebsiella oxytoca, and to assess the correlation with short-chain fatty acids production. The short-chain fatty acids formed in the fermentation of the probiotic/prebiotic combination were investigated using NMR spectroscopy, and the inhibitory activities were assessed by agar diffusion and co-culture methods. The results showed that Lactobacillus strains can inhibit K. oxytoca, and that this antagonism is influenced by the fructans source and probably associated with organic acid production.


Subject(s)
Fatty Acids, Volatile/metabolism , Fructans/analysis , Klebsiella oxytoca/physiology , Magnetic Resonance Spectroscopy/methods , Prebiotics/analysis , Probiotics/analysis , Fermentation/physiology , Gastrointestinal Microbiome/physiology , Gastrointestinal Tract/metabolism , Gastrointestinal Tract/microbiology , Klebsiella oxytoca/ultrastructure , Lactobacillus acidophilus/physiology , Lactobacillus acidophilus/ultrastructure , Microscopy, Electron, Scanning
6.
Water Sci Technol ; 81(2): 265-273, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32333659

ABSTRACT

Chemical products traditionally used in the disinfection of water bodies often pose human health risks. For this reason, studies on natural coagulants such as Moringa oleifera Lam. represent an alternative for the inactivation of pathogenic microorganisms, among which is Escherichia coli. This study evaluated the effect of different concentrations of coagulants obtained from Moringa seed extracts and their protein fractions in the inactivation of E. coli during the coagulation/flocculation process. The coagulants studied were the aqueous extract, saline extract and protein fractions albumin and globulin, highlighting that the protein fractions were more effective on inactivating E. coli. The protein fraction globulin at a concentration of 10.0 mg L-1 showed bactericidal effects against E. coli within 18 min, whereas the albumin showed a bacteriostatic effect within 48 min because it isolated colonies in the sediment sample.


Subject(s)
Moringa oleifera , Water Purification , Escherichia coli , Humans , Plant Extracts , Seeds , Water
7.
J Appl Biomed ; 18(4): 106-114, 2020 12.
Article in English | MEDLINE | ID: mdl-34907763

ABSTRACT

Carvacrol presents action in Salmonella Typhimurium biofilms, however the antibiofilm mechanism of this compound has not been fully established yet. In the present study, the aim was to evaluate protein profile changes in S. Typhimurium biofilm treated with carvacrol. Proteomic analysis of treated versus untreated biofilm showed several changes in proteins involved with S. Typhimurium biofilm and antioxidant activity. The proteins DsbA (thiol: disulfide interchange protein DsbA), LuxS (S-ribosylhomocysteine lyase), DksA (RNA polymerase binding transcription factor DksA), and SODs (superoxide dismutases) A, B and C had their synthesis decreased after treatment with carvacrol. These proteins play a key role in S. Typhimurium biofilm formation, demonstrating the dynamic antibiofilm action of carvacrol. The differentially expressed proteins identified provide possible action targets for future studies in order to gain more insight into the mechanism of action of carvacrol on S. Typhimurium biofilm.


Subject(s)
Proteomics , Salmonella typhimurium , Biofilms , Cymenes/pharmacology , Salmonella typhimurium/genetics
8.
Res Microbiol ; 169(1): 33-43, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28974445

ABSTRACT

The effect of cinnamaldehyde against biofilm cells of Salmonella Typhimurium ATCC 14028 was evaluated. We also assessed differential protein patterns that were expressed by biofilms compared with planktonic cells and protein expression by cinnamaldehyde-treated biofilms cells. This compound decreased biofilm biomass and metabolic activity of biofilms at both concentrations tested. Cinnamaldehyde treatment reduced the number of attached cells in polypropylene, reflected by colony count and scanning electron microscopy. The proteomic analysis of biofilms compared with planktonic cells indicated that several proteins were upregulated or downregulated, especially proteins that are involved in energy metabolism. Peroxiredoxin, ATP synthase alpha chain protein, conjugal transfer nickase/helicase TraI and elongation factor G were upregulated in untreated-biofilm cells, and their expression decreased as a function of cinnamaldehyde treatment. Cinnamaldehyde had antibiofilm activity, and several differentially expressed proteins identified provide potential and interesting targets to explore new control strategies for S. Typhimurium biofilms.


Subject(s)
Acrolein/analogs & derivatives , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/metabolism , Biofilms/drug effects , Salmonella typhimurium/drug effects , Acrolein/pharmacology , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Microbial Sensitivity Tests , Proteomics , Salmonella typhimurium/genetics , Salmonella typhimurium/metabolism
9.
PLoS One ; 11(8): e0160535, 2016.
Article in English | MEDLINE | ID: mdl-27504957

ABSTRACT

The effects of an alginate-based edible coating containing natural antioxidants (rosemary and oregano essential oils) on lipid oxidation, color preservation, water losses, texture and pH of beef steaks during 14 days of display were studied. The essential oil, edible coating and beef antioxidant activities, and beef consumer acceptability were also investigated. The edible coatings decreased lipid oxidation of the meat compared to the control. The coating with oregano was most effective (46.81% decrease in lipid oxidation) and also showed the highest antioxidant activity. The coatings significantly decreased color losses, water losses and shear force compared to the control. The coatings had a significant effect on consumer perception of odor, flavor and overall acceptance of the beef. In particular, the oregano coating showed significantly high values (approximately 7 in a 9-point scale). Active edible coatings containing natural antioxidants could improve meat product stability and therefore have potential use in the food industry.


Subject(s)
Antioxidants/chemistry , Consumer Behavior , Food Preservation/methods , Oils, Volatile/chemistry , Origanum/chemistry , Red Meat , Rosmarinus/chemistry , Alginates/chemistry , Animals , Cattle , Color , Food Quality , Food Storage , Glucuronic Acid/chemistry , Hexuronic Acids/chemistry , Hydrogen-Ion Concentration , Lipids/chemistry , Male , Mechanical Phenomena , Oxidation-Reduction
10.
Int J Food Microbiol ; 216: 121-6, 2016 Jan 04.
Article in English | MEDLINE | ID: mdl-26476327

ABSTRACT

Alicyclobacillus spp. are spore forming bacteria that are often related to the deterioration of acidic products such as beverages and citrus juices. After the process of industrial pasteurization, the spore produced by the bacteria can germinate and the microorganism can grow, causing sensory abnormalities in the product. Alternative biopreservatives, such as the antimicrobial compounds, are of considerable importance to the food industry. Papain and bromelain are proteolytic enzymes derived frompapaya and pineapple, respectively. These enzymes are widely used in medicine and in the pharmaceutical and food industries, but while some studies have described their antibacterial action, no studies of the Alicyclobacillus spp. exist. The aimof this studywas to analyze the antibacterial effect of papain and bromelain on Alicyclobacillus spp. through 1) determining minimum inhibitory and bactericidal concentration (MIC and MBC); 2) determining the death time curve of the micro-organism in the presence and absence of enzymes; and 3) investigating the enzymatic mechanism on the microorganism. The antibacterial activity of enzymes in combination with nisin was also evaluated. The results showed that for the Alicyclobacillus acidoterrestris strain, the MIC of papain was 0.98 µg/mL and the MBC was 3.91 µg/mL, while theMIC of bromelain was 62.5 µg/mL and the MBCwas 250 µg/mL. The concentration of 4 ×MIC for both the enzymes was sufficient to eliminate 4 logs of the micro-organism after 24 h of incubation. Through the use of enzyme inhibitors specific for cysteine proteases, it was found that the antibacterial activity of papain and bromelain is not related to its proteolytic activity, butmay be related to other activities, such as amidse and esterase. The synergistic activity of the enzymes revealed a fractional inhibitory concentration (FIC) level of 0.16. Combination with nisin revealed an FIC of 0.25 for papain and 0.19 for bromelain, indicating synergism between both compounds. The application of enzymes in reconstituted orange juice contaminated with A. acidoterrestris was found to be effective, as after 48 h of incubation, at three different temperatures, the initial microbial population was eliminated. This study showed that the enzymes papain and bromelain have an antibacterial effect on A. acidoterrestris.


Subject(s)
Alicyclobacillus/drug effects , Anti-Bacterial Agents/pharmacology , Bromelains/pharmacology , Nisin/pharmacology , Papain/pharmacology , Amidohydrolases/metabolism , Ananas/enzymology , Beverages/microbiology , Carica/enzymology , Citrus sinensis/microbiology , Cysteine Proteases/metabolism , Cysteine Proteinase Inhibitors/chemistry , Drug Synergism , Esterases/metabolism , Microbial Sensitivity Tests , Pasteurization
11.
J Food Prot ; 76(8): 1408-13, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23905797

ABSTRACT

This study evaluated the adhesion and biofilm formation of Alicyclobacillus acidoterrestris on industrial orange juice processing equipment and the bactericidal efficacy of peracetic acid, sodium hypochlorite, and quaternary ammonia after biofilm formation. The efficacy of these sanitizers against the spores of this microorganism was also evaluated. Stainless steel and nylon surfaces exhibited higher cell adhesion levels than did polyvinyl chloride surfaces. Peracetic acid was the most effective in removing biofilms from all surfaces (P < 0.05) and also reduced bacterial counts by 3 log CFU/cm² on the surface of polyvinyl chloride, but the other sanitizers also reduced the bacterial counts by 2 log CFU/cm². Quaternary ammonia exhibited the optimal minimum sporicidal concentration, preventing spore germination after only 15 s of contact at a concentration of 82 ppm. The flow cytometry results indicated that the spores and cells had low incidences of plasma membrane lysis after treatment with sanitizer, suggesting that lysis is not the principal mode of action for these sanitizers on A. acidoterrestris.


Subject(s)
Alicyclobacillus/physiology , Disinfectants/pharmacology , Alicyclobacillus/drug effects , Bacterial Adhesion/physiology , Biofilms/growth & development , Colony Count, Microbial , Dose-Response Relationship, Drug , Food Microbiology , Peracetic Acid/pharmacology , Sodium Hypochlorite/pharmacology , Spores, Bacterial/drug effects , Spores, Bacterial/growth & development , Stainless Steel
12.
BMC Res Notes ; 5: 352, 2012 Jul 11.
Article in English | MEDLINE | ID: mdl-22784664

ABSTRACT

BACKGROUND: There is no published information about the use of different protocols to administer a highly diluted medication.Evaluate the effect of different protocols for treatment with biotherapic T. cruzi 17 dH (BIOT(Tc17dH)) on clinical/parasitological evolution of mice infected with T. cruzi-Y strain. METHODS: A blind, randomized controlled trial was performed twice, using 60 28-day-old male Swiss mice infected with T. cruzi-Y strain, in five treatment groups: CI - treated with a 7% ethanol-water solution, diluted in water (10 µL/mL) ad libitum; BIOT(PI) - treated with BIOT(Tc17dH) in water (10 µL/mL) ad libitum during a period that started on the day of infection; BIOT(4DI) - treated with BIOT(Tc17dH) in water (10 µL/mL) ad libitum beginning on the 4th day of infection; BIOT(4-5-6) - treated with BIOT(Tc17dH) by gavage (0.2 mL/ animal/day) on the 4th, 5th and 6th days after infection; BIOT(7-8-9) - treated with BIOT(Tc17dH) by gavage (0.2 mL/ animal/day) on the 7th, 8th and 9th days after infection. We evaluated: parasitemia; total parasitemia (P(total)); maximum peak of parasites; prepatent period (PPP) - time from infection to detection of the parasite in blood; patent period (PP) - period when the parasitemia can be detected in blood; clinical aspects; and mortality. RESULTS: Parasitological parameters in the BIOT(PI) and mainly in the BIOT(4PI) group showed better evolution of the infection compared to the control group (CI), with lower P(total), lower maximum peak of parasites, higher PPP, lower PP and longer survival times. These animals showed stable body temperature and higher weight gain and water consumption, with more animals having normal-appearing fur for longer periods. In contrast, groups BIOT(4-5-6) and BIOT(7-8-9) showed worse evolution of the infection compared to the control group, considering both parasitological and clinical parameters. The correlation analysis combined with the other data from this study indicated that the prepatent period is the best parameter to evaluate the effect of a medication in this model. CONCLUSIONS: The BIOT(4DI) group showed the best clinical and parasitological evolution, with lower parasitemia and a trend toward lower mortality and a longer survival period. The prepatent period was the best parameter to evaluate the effect of a medication in this model.


Subject(s)
Antiparasitic Agents/pharmacology , Biological Products/pharmacology , Biological Therapy , Chagas Disease/drug therapy , Homeopathy , Trypanosoma cruzi/drug effects , Animals , Chagas Disease/blood , Chagas Disease/parasitology , Chagas Disease/physiopathology , Disease Models, Animal , Male , Mice , Parasitemia/drug therapy , Time Factors , Trypanosoma cruzi/growth & development
13.
Mem Inst Oswaldo Cruz ; 98(2): 283-6, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12764448

ABSTRACT

Ethanolic crude extracts from the roots of Chaptalia nutans, traditionally used in Brazilian folk medicine, were screened against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa by using the disk diffusion test technique. S. aureus with 14 mm inhibition zone was considered susceptible. E. coli and P. aeruginosa without such a zone were considered resistant. As a result of this finding, the ethanolic crude extract was fractionated on silica gel column chromatography into five fractions. The ethyl acetate fraction was active against S. aureus and Bacillus subtilis. Further column chromatography separation of the ethyl acetate fraction afforded 30 fractions, which were assayed against S. aureus. Fractions 16 and 17 showed inhibition zones with S. aureus, indicating the presence of active compounds, and were subjected to purification by repeated preparative thin layer chromatography. The pure compound 7-O-beta-D-glucopyranosyl-nutanocoumarin inhibited B. subtilis and S. aureus at concentrations of 62.5 g/ml and 125 g/ml, respectively. The antibacterial property of C. nutans appears to have justified its use for the treatment of wounds, which are contaminated through bacterial infections.


Subject(s)
Anti-Bacterial Agents/pharmacology , Asteraceae , Coumarins/pharmacology , Escherichia coli/drug effects , Glucosides/pharmacology , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Plant Extracts/pharmacology , Plants, Medicinal
14.
Am J Trop Med Hyg ; 66(1): 91-102, 2002 Jan.
Article in English | MEDLINE | ID: mdl-12135276

ABSTRACT

A Western blot method that uses antigens from culture promastigote forms of Leishmania (Viannia) braziliensis, L. (Leishmania) amazonensis, L. (Leishmania) tropica, and a trypanosomatid (strain 268T) isolated from naturally infected tomatoes was evaluated for laboratory diagnosis of American tegumentary leishmaniasis (ATL). Serum samples were obtained from 108 patients with ATL (group I), 23 chagasic patients (group II), 32 patients with other diseases (group III), and 78 healthy individuals (group IV). The overall analysis showed a sensitivity of 76.90%, 90.40%, 78.50%, and 87.90%, a specificity of 100%, 93.80%, 87.80%, and 77.10%, a positive predictive value of 100%, 94.00%, 89.50%, and 72.50%, a negative predictive value of 75.70%, 90.00%, 75.40%, and 90.20%, and a concordance coefficient kappa of 0.7358, 0.8400, 0.6491, and 0.6287 for L. (V.) braziliensis, L. (L.) amazonensis, L. (L.) tropica, and strain 268T antigens, respectively. The antigenic profile recognized by serum samples from patients with ATL and with Chagas' disease permits serologic distinction between these infections.


Subject(s)
Antigens, Protozoan/analysis , Blotting, Western/methods , Leishmania/immunology , Leishmaniasis, Cutaneous/diagnosis , Animals , Brazil , Chagas Disease/diagnosis , Fluorescent Antibody Technique, Indirect , Humans , Leishmania/isolation & purification , Leishmaniasis, Cutaneous/parasitology , Predictive Value of Tests , Sensitivity and Specificity , Skin Tests
SELECTION OF CITATIONS
SEARCH DETAIL
...