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1.
Mar Drugs ; 22(3)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38535478

RESUMO

We demonstrated the effect of Ishige okamurae extract (IOE) on the receptor activator of nuclear factor-κB ligand (RANKL)-promoted osteoclastogenesis in RAW 264.7 cells and confirmed that IOE inhibited RANKL-induced tartrate-resistant acid phosphatase (TRAP) activity and osteoclast differentiation. IOE inhibited protein expression of TRAP, metallopeptidase-9 (MMP-9), the calcitonin receptor (CTR), and cathepsin K (CTK). IOE treatment suppressed the expression of activated T cell cytoplasmic 1 and activator protein-1, thus controlling the expression of osteoclast-related factors. Moreover, IOE significantly reduced RANKL-phosphorylated extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK). It also reduced the RANKL-induced phosphorylation of NF-κB and nuclear translocation of p65. IOE inhibited Dex-induced bone loss and osteoclast-related gene expression in zebrafish larvae. HPLC analysis shows that IOE consists of 3.13% and 3.42% DPHC and IPA, respectively. Our results show that IOE has inhibitory effects on osteoclastogenesis in vitro and in vivo and is a potential therapeutic for osteoporosis.


Assuntos
Osteogênese , Peixe-Zebra , Animais , Osteoclastos , Cromatografia Líquida de Alta Pressão , MAP Quinases Reguladas por Sinal Extracelular , Ligante RANK
2.
FEMS Microbiol Lett ; 3702023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-37777836

RESUMO

Bacterial population exposed to stressful antibiotic conditions consists of various subpopulations such as tolerant, persister, and resistant cells. The aim of this study was to evaluate the phenotypic heterogeneity of Salmonella Typhimurium preadapted to sublethal concentrations of antibiotics. Salmonella Typhimurium cells were treated with 1/2 × MIC of antibiotics for the first 48 h and successively 1 × MIC for the second 24 h at 37°C, including untreated control (CON), no antibiotic and 1 × MIC ciprofloxacin (NON-CIP), 1/2 × MIC ciprofloxacin and 1 × MIC ciprofloxacin (CIP-CIP), 1/2 × MIC tetracycline and 1 × MIC ciprofloxacin (TET-CIP), no antibiotic and 1 × MIC tetracycline (NON-TET), 1/2 × MIC ciprofloxacin and 1 × MIC tetracycline (CIP-TET), and 1/2 × MIC tetracycline and 1 × MIC tetracycline (TET-TET). All treatments were evaluated by antibiotic susceptibility, ATP level, relative fitness, cross-resistance, and persistence. S. Typhimurium cells were more susceptible to non-adapted NON-CIP and NON-TET (>3-log reduction) than pre-adapted CIP-CIP, TET-CIP, CIP-TET, and TET-TET. CON exhibited the highest ATP level, corresponding to the viable cell number. The relative fitness levels were more than 0.95 for all treatments, except for NON-CIP (0.78). The resistance to ciprofloxacin and tetracycline was increased at all treatments with the exception of NON-TET. The persister cells were noticeably induced at CIP-TET treatment, showing more than 5 log CFU mL-1. The results suggest that the antibiotic preadaptation led to heterogeneous populations including persisters that can develop to resistance. This study provides new insight in the bacterial persistence associated with their potential risk and paves the way to design antibiotic therapy targeting dormant bacteria.


Assuntos
Ciprofloxacina , Salmonella typhimurium , Ciprofloxacina/farmacologia , Salmonella typhimurium/genética , Antibacterianos/farmacologia , Tetraciclina/farmacologia , Trifosfato de Adenosina , Testes de Sensibilidade Microbiana
3.
Sci Adv ; 9(43): eadg6194, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37889968

RESUMO

An extensive evaluation of disease occurrence after statin use based on a "hypothesis-free" approach remains scarce. To examine the effect of statin use on the potential risk of developing diseases, a propensity score-matched cohort study was executed using data from the National Sample Cohort in South Korea. A total of 7847 statin users and 39,235 nonstatin users were included in the final analysis. The period of statin use was defined as our main time-dependent exposure and was divided into three periods: current, recent, and past. The main outcomes were defined as new-onset diseases with ≥100 events based on the International Statistical Classification of Diseases, 10th Revision. We calculated the adjusted hazard ratios and 95% confidence intervals (CIs) using Cox regression. We found that statin use significantly increased the risk of developing iron deficiency anemia up to 5.04 times (95% CI, 2.11 to 12.03). Therefore, the iron levels of patients using statins should be monitored carefully.


Assuntos
Anemia Ferropriva , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Estudos de Coortes , Anemia Ferropriva/epidemiologia , Estudos Retrospectivos , República da Coreia/epidemiologia
4.
Mar Drugs ; 21(7)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37504908

RESUMO

The balance between bone-resorbing osteoclasts and bone-forming osteoblasts is essential for the bone remodeling process. This study aimed to investigate the effect of Ishophloroglucin A (IPA) isolated from Ishige okamurae on the function of osteoclasts and osteoblasts in vitro. First, we demonstrated the effect of IPA on osteoclastogenesis in receptor activator of nuclear factor κB ligand (RANKL)-induced RAW 264.7 cells. IPA inhibited the tartrate-resistant acid phosphatase (TRAP) activity and osteoclast differentiation in RANKL-induced RAW 264.7 cells. Moreover, it inhibited the RANKL-induced osteoclast-related factors, such as TRAP, matrix metalloproteinase-9 (MMP-9), and calcitonin receptor (CTR), and transcription factors, such as nuclear factor of activated T cells 1 (NFATc1) and c-Fos. IPA significantly suppressed RANKL-activated extracellular signal-regulated kinase (ERK), and NF-κB in RAW 264.7 cells. Our data indicated that the ERK and NF-κB pathways were associated with the osteoclastogenesis inhibitory activity of IPA. Next, we demonstrated the effect of IPA on osteoblastogenesis in MG-63 cells. IPA significantly promoted alkaline phosphatase (ALP) activity in MG-63 cells, along with the osteoblast differentiation-related markers bone morphogenetic protein 2 (BMP2), type 1 collage (COL1), p-Smad1/5/8, and Runx2, by activating the MAPK signaling pathways. Taken together, the study indicated that IPA could be effective in treating bone diseases, such as osteoporosis.


Assuntos
NF-kappa B , Osteogênese , Animais , Camundongos , NF-kappa B/metabolismo , Transdução de Sinais , Fatores de Transcrição NFATC/metabolismo , Fatores de Transcrição NFATC/farmacologia , Osteoclastos , Ligante RANK/farmacologia , Ligante RANK/metabolismo , Diferenciação Celular , Células RAW 264.7
5.
Sci Rep ; 12(1): 20690, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36450739

RESUMO

Intrinsic immunologic disparity of psoriasis itself, along with chronic inflammation and immunomodulatory anti-psoriatic treatments could be associated with increased risk of malignancy. We aimed to estimate the risk of malignancy in patients with psoriasis by treatment modality compared with that in individuals without psoriasis in Korea. We conducted a nationwide cohort study using the claims database of the National Health Insurance Service from January 2005 to December 2018. A total of 255,471 patients with psoriasis, and age- and sex-matched non-psoriasis participants (1:1 ratio) were enrolled. The adjusted hazard ratios (aHRs) [95% confidence intervals (CIs)] for malignancy without nonmelanoma skin cancer (NMSC) were 1.10 [1.08-1.12] in patients with psoriasis, 1.13 [1.00-1.27], 1.05 [0.97-1.13], and 1.24 [0.84-1.83] in phototherapy, non-biologic systemics, and biologics cohort, respectively. Among the non-biologic systemics cohort, patients treated with cyclosporin showed higher risk of malignancy without NMSC (aHR [95% CI], 1.20 [1.04-1.39]). The risk of malignancy without NMSC in patients with psoriasis was higher than that in individuals without psoriasis. Phototherapy and biologics were not associated with significant increase of risk; however, cyclosporin appeared to increase its risk. Dermatologists should be vigilant about this potential risk while managing patients with psoriasis.


Assuntos
Psoríase , Neoplasias Cutâneas , Humanos , Estudos de Coortes , Psoríase/complicações , Psoríase/tratamento farmacológico , Psoríase/epidemiologia , Ciclosporina , República da Coreia/epidemiologia
7.
J Food Prot ; 77(5): 758-64, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24780330

RESUMO

The aim of this study was to evaluate the phenotypic and genotypic properties of nonlysogenic Salmonella Typhimurium (ST(P22-)) and lysogenic Salmonella Typhimurium (ST(P22+)) in the presence of sublethal concentrations (SLC2D) of citrus essential oils (CEOs), which were used to evaluate antimicrobial susceptibility, cell surface hydrophobicity, autoaggregation ability, bacterial motility, lysogenic conversion, gene expression patterns, and antibiofilm formation. The SLC2D values of non-heat-treated (N-CEO) and heat-treated (H-CEO) CEO in an autoclave at 121°C for 20 min were 2.0 to 2.1 mg/ml against ST(P22-) and 1.7 to 1.9 mg/ml against STP(22+). The rates of injured ST(P22-) and ST(P22+) cells treated with SLC2D of N-CEO and H-CEO ranged from 67 to 83%. The hydrophobicity and autoaggregation were decreased to 2.5 and 19.5% for ST(P22-) and 4.7 and 21.7% for ST(P22+), respectively, in the presence of N-CEO. A noticeable reduction in the swarming motility was observed in ST(P22-) with N-CEO (14.5%) and H-CEO (13.3%). The numbers of CEO-induced P22 were 5.40 log PFU/ml for N-CEO and 5.65 log PFU/ml for H-CEO. The relative expression of hilA, hilC, hilD, invA, invC, invE, invF, sirA, and sirB was down-regulated in ST(P22-) and ST(P22+) with N-CEO and H-CEO. The numbers of adherent ST(P22-) and ST(P22+) were effectively reduced by more than 1 log in the presence of CEO. These results suggest that CEO has potential to be used to control bacterial attachment, colonization, and invasion.


Assuntos
Bacteriófago P22/fisiologia , Citrus/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/virologia , Proteínas de Bactérias/genética , Regulação para Baixo/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Lisogenia
8.
Arch Microbiol ; 196(3): 201-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24500522

RESUMO

This study was designed to evaluate the effect of bacteriophage P22 on the susceptibility, swimming motility, invasion gene expression, invasive ability, and intracellular survival of Salmonella Typhimurium exposed to the simulated intestinal conditions. S. Typhimurium cells were inoculated at 37 °C for 4 h in the simulated intestinal conditions with or without bacteriophage P22, including control (0 % bile salts, pH 7.2), SN (0 % bile salts, pH 5.0), SL (0.5 % bile salts, pH 5.0), SH (2.0 % bile salts, pH 5.0), SNp (0 % bile salts + P22, pH 5.0), SLp (0.5 % bile salts + P22, pH 5.0), and SHp (2.0 % bile salts + P22, pH 5.0). The numbers of Typhimurium cells were significantly reduced by 3.30, 3.56, and 3.75 log units, respectively, at SNp, SLp, and SHp. Considerable reduction in the swimming motility was observed at SNp (23 %), SLp (22 %), and SHp (20 %). The transcriptional regulator genes, hilA, hilC, hilD, invA, invE, and invF, were significantly down-regulated with SHp, showing 4.07-fold, 2.87-fold, 3.43-fold, 2.07-fold, 1.44-fold, and 4.83-fold, respectively. The decrease in invasive ability was most significant at SHp (45 %), followed by SLp (49 %). These results suggest that bacteriophage P22 can be used as an alternative to control Salmonella invasion of epithelial cells.


Assuntos
Bacteriófagos/fisiologia , Células Epiteliais/microbiologia , Intestinos/microbiologia , Salmonella typhimurium/fisiologia , Salmonella typhimurium/virologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular , Regulação Bacteriana da Expressão Gênica , Humanos , Viabilidade Microbiana , Salmonella typhimurium/genética
9.
Biol Trace Elem Res ; 157(2): 101-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24402636

RESUMO

Obesity is a chronic inflammatory state characterized by altered adipokine production and increased levels of inflammatory cytokines. The study explored the effect of zinc supplementation on inflammatory markers and adipocyte hormones in young obese women. Twenty five non-obese women and forty obese women (body mass index ≥25 kg/m(2)) aged 19-28 years were recruited for this study. Twenty obese women of the study group took 30 mg/day of supplemental zinc as zinc gluconate for 8 weeks and 20 obese women of control group took placebo. Usual dietary zinc intake was estimated from 3-day diet records. Serum zinc and urinary zinc concentration were measured by Atomic Absorption Spectrophotometry. Inflammatory markers such as high sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α), and interleukin (IL)-6 and adipocyte hormones such as lepin and adiponectin were measured by enzyme immunoassay. Inflammatory markers and leptin were significantly higher, but adiponectin was significantly lower in obese women than non-obese women. Zinc supplementation increased serum zinc by 15% and urinary zinc by 56% (P < 0.05). The levels of hs-CRP (P = 0.03) and IL-6 (P = 0.006) significantly decreased with zinc supplementation, but not in placebo group. Serum leptin and plasma adiponectin concentration did not differ with either zinc supplementation or placebo. The levels of IL-6 and leptin were inversely associated with dietary zinc intake. These results suggest that zinc may have a favorable effect on obesity-related inflammation in young adults.


Assuntos
Adipocinas/sangue , Citocinas/sangue , Suplementos Nutricionais , Obesidade/tratamento farmacológico , Zinco/uso terapêutico , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Proteína C-Reativa/análise , Método Duplo-Cego , Feminino , Humanos , Interleucina-6/sangue , Leptina/sangue , Obesidade/imunologia , Espectrofotometria Atômica , Adulto Jovem , Zinco/administração & dosagem , Zinco/sangue , Zinco/urina
10.
FEMS Microbiol Lett ; 352(1): 11-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24417259

RESUMO

This study was designed to evaluate the effects of bacteriophage on the intracellular survival and immune mediator gene expression in chicken macrophage-like HD11 cells. The invasive ability and intracellular survival of Salmonella Typhimurium (ST(P22-) ) and lysogenic S. Typhimurium (ST(P22+) ) in HD11 cells were evaluated at 37 °C for 24 h postinfection (hpi). The expression of inflammatory mediator genes was determined in ST(P22-) - and ST(P22+) -infected HD11 cells treated with and without bacteriophage P22 at 1 and 24 hpi using quantitative RT-PCR. The ability of ST(P22-) and ST(P22+) to invade HD11 cells was significantly decreased by bacteriophage P22 at 1 hpi. The numbers of intracellular ST(P22-) and ST(P22+) were significantly decreased from 2.39 to 1.62 CFU cm(-2) and from 3.40 to 1.72 CFU cm(-2) in HD11 cells treated with bacteriophage P22, respectively, at 24 hpi. The enhanced expression of inflammatory mediators was observed in ST(P22-) - and ST(P22+) -infected HD11 cells treated with and without bacteriophage P22. These results suggest that the application of bacteriophage could be an effective way to control the intracellular infection.


Assuntos
Bacteriófago P22/fisiologia , Terapia Biológica/veterinária , Citocinas/genética , Macrófagos/imunologia , Doenças das Aves Domésticas/terapia , Salmonelose Animal/terapia , Salmonella typhimurium/virologia , Animais , Linhagem Celular , Galinhas , Citocinas/imunologia , Mediadores da Inflamação/imunologia , Macrófagos/microbiologia , Macrófagos/virologia , Dados de Sequência Molecular , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/genética , Salmonelose Animal/imunologia , Salmonelose Animal/microbiologia , Salmonella typhimurium/fisiologia
11.
Mar Biotechnol (NY) ; 13(2): 205-14, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20405153

RESUMO

The effect of ultrasonic extraction on extraction yields, cytotoxicity, and anticancer activity of Spirulina maxima was investigated in this study. Optimal extraction conditions were determined as 60 kHz frequency at 60°C for 30 min with 120 W intensity, which resulted in 19.3% of extraction yields and 19.1% of cytotoxicity on normal human cells. Yields from conventional water and ethanol extraction were 15.8% at 100°C and 8.3% at 80°C, respectively. It was found that the extracts obtained by ultrasonic extraction process selectively inhibited the digestive-related cancer cell lines, such as human stomach cancer cells, having 89% of the highest inhibition ratio and 4.5 of the highest selectivity. In adding 0.5 mg/mL of the extract, human promyelocytic leukemia cells' cell differentiation was increased 1.72 times over that of the control. Expression level of B cell lymphoma-2 from Hep3B cell was also effectively suppressed by the extract obtained at 60 kHz and 60°C, leading to the inhibition of the early step of carcinogenesis. This work suggests that anticancer activity of the extracts is due to water-soluble polysaccharides rather than proteins and is further supported by the result that the ultrasonification extraction process can efficiently extract relatively intact polysaccharides rather than digesting the proteins in S. maxima by matrix assisted laser desorption ionization-time of flight and high performance size exclusion chromatography chromatogram analyses. Therefore, ultrasonic extraction increases both extraction yield and the biological activity of S. maxima extracts, which might be useful as an alternative natural anticancer agent in the medical and food industries.


Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Citotoxinas/farmacologia , Ondas de Choque de Alta Energia , Spirulina/química , Antineoplásicos/química , Produtos Biológicos/química , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Citotoxinas/química , Ensaios de Seleção de Medicamentos Antitumorais , Etanol/química , Inibidores do Crescimento/farmacologia , Humanos , Temperatura
12.
Cytotechnology ; 62(5): 461-72, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20936343

RESUMO

This work was to investigate the effect of flavonoids from Angelica gigas Nakai on the proliferation and differentiation of PC12 cells. Several solvents including hexane, chloroform, ethyl acetate, butanol and water consecutively partitioned. We determined the ethanol crude extract of Angelica gigas Nakai. The hexane fraction was shown to contain the highest number of flavonoids as follows; 21.48 mg/g and the composition of the flavonoids was as follows: 12.24 mg/g of quercetin, 4.39 mg/g of myricetin and 2.58 mg/g of catechin. In addition, this hexane fraction greatly increased both cell growth and outgrowth of the neurite, and whose effects were three times higher than those of the other fractions. The length of the neurites was measured as ca. 110 µm in adding 50 µg/mL of the hexane fraction, which was about the same as the case of adding 50 ng/mL of NGF as a positive control. This result indicates that the differentiation of PC12 cells by the addition of the hexane fraction was comparable to the case of adding NGF. The hexane fraction was also determined to prevent apoptosis of PC12 cells by suppressing DNA fragmentation. It is interesting that the mixture of three major flavonoids, quercetin, myricetin and catechin showed stronger activity on, both PC12 cell growth and neuritis outgrowth, than when adding each flavonoid alone. We believe this was due to the synergistic effects of the three flavonoids. The activities of these flavonoids from Angelica gigas Nakai are reported for the first time in this study.

13.
J Agric Food Chem ; 58(3): 1719-25, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-20000575

RESUMO

This study was designed to evaluate the combined effects of probiotic fermentation and high-pressure extraction (HPE) on the functional properties of Codonopsis lanceolata. The ground C. lanceolata samples were anaerobically fermented with Lactobacillus acidophilus ADH, Bifidobacterium longum B6, Lactobacillus rhamnosus GG, or Lactobacillus paracasei at 37 degrees C for 10 days and subjected to 500 MPa at 50 degrees C for 30 min. The extraction yields of C. lanceolata samples were noticeably increased to 29-32% by HPE. The B. longum-fermented C. lanceolata samples extracted by high pressure (BLF-HPE) exhibited the highest antimicrobial activity (MIC < 14 mg/mL) against Listeria monocytogenes, Staphylococcus aureus, Shigella boydii, and Salmonella typhimurium. The nonfermented C. lanceolata samples extracted with high pressure (NF-HPE) had the highest total phenolic content (13.3 mg of GAE/g). The lowest effective concentrations (EC(50) and EC(0.5)) were 4.55 and 1.76 mg/mL, respectively, for NF-HPE extracts, indicating its highest antioxidant activity. The BLF-HPE and L. rhamnosus-fermented C. lanceolata samples extracted by high pressure (LRF-HPE) exhibited the highest antimutagenic activities in S. typhimurium TA 100, which were 82 and 83% inhibition, respectively. The use of probiotic fermentation and HPE can produce more biologically active compounds in C. lanceolata than the conventional solvent extraction method. The results provide pharmaceutically useful information for improving biological properties and an approach to drug discovery.


Assuntos
Anti-Infecciosos/metabolismo , Antimutagênicos/metabolismo , Antioxidantes/metabolismo , Bifidobacterium/metabolismo , Fracionamento Químico/métodos , Codonopsis/química , Fermentação , Lactobacillus/metabolismo , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Antimutagênicos/química , Antimutagênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Fracionamento Químico/instrumentação , Codonopsis/microbiologia , Pressão , Probióticos/metabolismo
14.
J Biosci Bioeng ; 107(3): 331-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19269602

RESUMO

High-pressure extraction and ultrasonification extraction techniques were employed to extract bioactive compounds from Berberis koreana. This study aimed to determine the effect of ultrasonification in a high pressure process on the extraction yield, and the anticancer and antioxidant activities of the B. koreana bark extract. The effect of high-pressure extraction time when carried out for 5 and 15 min (HP5 and HP15) was also investigated. The best extraction yield with maximum percentage of phenolic compounds was obtained using high pressure with sonification (HPWS) extraction method. Experimental results indicated that HPWS altered the antioxidant activities, including the scavenging capacity of diphenylpicrylhydrazyl (DPPH) and xanthine oxidase. HP5 and HP15 with conventional extraction have almost similar bioactivity, but showed lower antioxidant and anticancer activities compared to HPWS. The results showed that the application of ultrasonification improved the extraction efficiency for bioactive compounds and, as deduced from chromatographic profiles, it may have allowed the release of new compounds. The scanning electron microscope (SEM) showed evidence of rupturing of the tissue surface treated with HPWS, in contrast to conventional extraction, HP5, and HP15. The HPWS extraction was not only more efficient but also convenient for the recovery and purification of the active compounds of hard plant tissues.


Assuntos
Antineoplásicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Berberis/química , Sobrevivência Celular/efeitos dos fármacos , Sequestradores de Radicais Livres/isolamento & purificação , Casca de Planta/química , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Sequestradores de Radicais Livres/farmacologia , Humanos , Extratos Vegetais/farmacologia
15.
J Food Prot ; 67(1): 148-55, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14717365

RESUMO

Inhibition of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes by grape seed extract (ActiVin) and pine bark extract (Pycnogenol) and the effect of these natural extracts on the oxidative stability of raw ground beef were studied. In an agar dilution test, the MICs of ActiVin and Pycnogenol were determined to be 4.0 mg/ml for 4.43 log CFU per plate of E. coli O157:H7 and 4.0 mg/ml for 4.38 log CFU per plate of L. monocytogenes. In an inhibition curve test, populations of E. coli O157:H7, Salmonella Typhimurium, and L. monocytogenes fell to below the detection limit (10 CFU/ml) after 16 h of incubation. The numbers of E. coli O157:H7, L. monocytogenes, and Salmonella Typhimurium declined by 1.08, 1.24, and 1.33 log CFU/g, respectively, in raw ground beef treated with 1% Pycnogenol after 9 days of refrigerated storage. ActiVin (1%) and oleoresin rosemary (1%) resulted in an approximately 1-log CFU/g reduction in the populations of all three pathogens after 9 days. The addition of 1% ActiVin and Pycnogenol contributed to the maintenance of an acidic pH of 5.80 and 5.58, respectively, in raw ground beef. Compared to the control, all treatments increased in L* (lightness), with the exception of ActiVin. ActiVin and oleoresin rosemary had the highest a* (redness) and b* (yellowness) values, respectively. ActiVin most effectively retarded lipid oxidation, followed by Pycnogenol. The results suggest that these natural extracts have potential to be used with other preservative methods to reduce pathogenic numbers, lipid oxidation, and color degradation in ground beef.


Assuntos
Escherichia coli O157/crescimento & desenvolvimento , Conservação de Alimentos , Listeria monocytogenes/crescimento & desenvolvimento , Produtos da Carne/microbiologia , Extratos Vegetais/farmacologia , Salmonella typhimurium/crescimento & desenvolvimento , Animais , Bovinos , Contagem de Colônia Microbiana , Cor , Relação Dose-Resposta a Droga , Escherichia coli O157/efeitos dos fármacos , Flavonoides/farmacologia , Microbiologia de Alimentos , Peroxidação de Lipídeos/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Produtos da Carne/normas , Testes de Sensibilidade Microbiana , Oxirredução , Salmonella typhimurium/efeitos dos fármacos , Substâncias Reativas com Ácido Tiobarbitúrico/análise
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