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Thymol

Distribution by Scientific Domains

Chemistry	58%
Life Sciences	22%
Medical Sciences	18%

Selected Abstracts

THE ANTIBACTERIAL EFFECT OF CINNAMALDEHYDE, THYMOL, CARVACROL AND THEIR COMBINATIONS AGAINST THE FOODBORNE PATHOGEN SALMONELLA TYPHIMURIUM

JOURNAL OF FOOD SAFETY, Issue 2 2007
FENG ZHOU
ABSTRACT The aim of this study was to investigate the antimicrobial activity of cinnamaldehyde, thymol and carvacrol alone or their combinations against Salmonella Typhimurium. The results showed that the lowest concentrations of cinnamaldehyde, thymol and carvacrol inhibiting the growth of S. Typhimurium significantly were 200, 400 and 400 mg/L, respectively. In a system combining different antimicrobials, treatments with cinnamaldehyde/thymol, cinnamaldehyde/carvacrol and thymol/carvacrol revealed significantly less population of S. Typhimurium and had synergy effect compared with samples treated with cinnamaldehyde, thymol or carvacrol alone. By means of their paired combinations, the lowest addition of cinnamaldehyde, thymol and carvacrol could be decreased from 200, 400 and 400 mg/L to 100, 100 and 100 mg/L, respectively. [source]

Thymol analogues with antioxidant and L-type calcium current inhibitory activity

DRUG DEVELOPMENT RESEARCH, Issue 4 2005
Ai-Yu Shen
Abstract Thymol is a natural product, which has antioxidant activity. 4-Morpholinomethyl-2-isopropyl-5-methylphenol (THMO), and 4-Pyrrolidinomethyl-2-isopropyl- 5-methylphenol (THPY) were synthesized by reacting thymol with formaldehyde and, respectively, morpholine or pyrrolidine. Since there is a relationship between the antioxidative status and incidence of human disease, anti-superoxidation, free radical scavenger activity, and anti-lipid peroxidation of the thymol analogues were determined by xanthine oxidase inhibition, cytochrome C system with superoxide anion releasing with formyl-Met-Leu-Phe (fMLP)/cytochalasin (CB) or phorbol myristate acetate (PMA) activating pathway in human neutrophils. All compounds studied had antioxidant activity. Mannich bases derived from thymol were generally found to be more potent compounds than thymol. THMO demonstrated the greatest antioxidant activity with IC50 values for xanthine oxidase inhibition and anti-lipid peroxidation being 21±2.78 and 61.29±5.83 µM, respectively. Moreover, since oxidative stress by free radical regulates the activity of L-type Ca2+ channel, the whole-cell configuration of the patch-clamp technique was used to investigate the effect of THMO upon ionic currents within NG108-15 cells. THMO (10 µM) suppressed the peak amplitude of L-type Ca2+ inward current (ICa,L), indicating that the antioxidative potential of the thymol analogues might be related to calcium current inhibition. The present studies suggest that THMO-dependent antioxidant and calcium ion current inhibition activity may be useful in treating free radical-related disorders. Drug Dev Res 64:195,202, 2005. © 2005 Wiley-Liss, Inc. [source]

Combined effects of thymol, carvacrol and grapefruit seed extract on lipid oxidation and colour stability of poultry meat preparations

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2009
Annalisa Lucera
Summary The combined effects of thymol, carvacrol and grapefruit seed extract (GFSE) on lipid oxidation and colour stability of poultry meat preparations packaged in air or modified atmospheres (MAP: 5% O2; 30% CO2; 65% N2) were investigated using a simplex centroid mixture design. Lipid oxidation was evaluated through measurement of secondary oxidation products (malonaldehyde, MDA) and general appearance with visual assessment and instrumental measurement of colour. Thymol and carvacrol, as individual antioxidants, retarded the oxidation process by maintaining MDA values below 2 mg kg,1 meat. The effect of GFSE was less than thymol and carvacrol. Redness (a*) decreased in all treatments during storage but this reduction was more evident in the control and in samples containing GFSE than in thymol and carvacrol. Although colour acceptability decreased with time, all meat preparations packaged in air maintained desirable appearance better than samples in MAP. Also, off-odours developed faster in the samples packaged in MAP than in aerobically packaged samples. [source]

Thymol and modified atmosphere packaging to control microbiological spoilage in packed fresh cod hamburgers

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2009
Maria Rosaria Corbo
Summary A study on the use of mild technologies to produce packaged fish hamburgers was presented. In particular, the antimicrobial effect of some natural compounds (carvacrol, eugenol, thymol, green tea extract, rosemary extract, grapefruit seed extract and lemon extract), at various concentrations (500,10 000 ppm), was screened in vitro against the main fish spoilage micro-organisms (Shewanella putrefaciens and Photobacterium phosphoreum). Lemon extract and thymol, in combination with modified atmosphere packaging, showed the greatest inhibition activity, therefore, thymol was subsequently used as an ingredient for producing fish hamburgers. Results pointed out that this combination is effective in controlling the growth of microbial species mainly involved in fresh fish spoilage; in particular, it significantly (P < 0.05) reduced the growth rate of bacterial population, performing about 4.8 log CFU g,1 and 6.5 log CFU g,1 reduction of the hydrogen sulphide producing bacteria and psychrotrophic aerobic specific spoilage organisms cell load, respectively, if compared with the control. [source]

Combination of a urease inhibitor and a plant essential oil to control coliform bacteria, odour production and ammonia loss from cattle waste

JOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2007
V.H. Varel
Abstract Aim:, To evaluate urea hydrolysis, volatile fatty acid (VFA) production (odour) and coliforms in cattle waste slurries after a urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) and a plant oil component (thymol) were added. Methods and Results:, Faeces from cattle fed a diet of 70% corn silage and 30% alfalfa haylage, urine and distilled water in the ratio 50 : 35 : 15 were blended at high speed for 1 min. Triplicate aliquots of 750 ml were amended with NBPT plus or minus thymol and reblended for 1 min, and were poured into 1·6 l wide-mouth jars covered 90% with a lid. After 56 days, thymol (2000 mg kg,1 waste) in combination with NBPT (80 mg kg,1 waste) retained 5·2 g of an initial 9·2 g of urea in cattle waste slurries, compared with less than 1 g of urea retained when NBPT was the only additive (P < 0·05). Another experiment using excreta from cattle fed 76·25% high moisture corn, 19·25% corn silage and a 4·5% supplement, blended at a low speed, gave a similar response with urea hydrolysis; and the two treatments, thymol alone and thymol in combination with NBPT, reduced VFA production (P < 0·01) and eliminated all coliform bacteria by day 1. A third experiment indicated coliforms disappeared in the no addition treatment after 8 days; however, they were viable at 6·6 × 104 CFU g,1 waste beyond 35 days in the NBPT treatment. Conclusions:, Thymol supplements the effect of NBPT by increasing the inhibitory period for hydrolysis of urea in cattle waste slurries and nitrogen retention in the waste. Significance and Impact of the Study:, Thymol and NBPT offer the potential to reduce odour and pathogens in cattle manure, and increase the fertilizer value. [source]

Antibacterial activities of essential oils and extracts of Turkish Achillea, Satureja and Thymus species against plant pathogenic bacteria

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2010
Recep Kotan
Abstract BACKGROUND: The aims of this study were to examine the chemical composition of the essential oils and hexane extracts of the aerial parts of Satureja spicigera (C. Koch) Boiss., Thymus fallax Fisch. & CA Mey, Achillea biebersteinii Afan, and Achillea millefolium L. by GC and GC,MS, and to test antibacterial efficacy of essential oils and n -hexane, chloroform, acetone and methanol extracts as an antibacterial and seed disinfectant against 25 agricultural plant pathogens. RESULTS: Thymol, carvacrol, p -cymene, thymol methyl ether and ,-terpinene were the main constituents of S. spicigera and T. fallax oils and hexane extracts. The main components of the oil of Achillea millefolium were 1,8-cineole, ,-cadinol and caryophyllene oxide, whereas the hexane extract of this species contained mainly n -hexacosane, n -tricosane and n -heneicosane. The oils and hexane extracts of S. spicigera and T. fallax exhibited potent antibacterial activity over a broad spectrum against 25 phytopathogenic bacterial strains. Carvacrol and thymol, the major constituents of S. spicigera and T. fallax oils, also showed potent antibacterial effect against the bacteria tested. The oils of Achillea species showed weak antibacterial activity. Our results also revealed that the essential oil of S. spicigera, thymol and carvacrol could be used as potential disinfection agents against seed-borne bacteria. CONCLUSION: Our results demonstrate that S. spicigera, T. fallax oils, carvacrol and thymol could become potentials for controlling certain important agricultural plant pathogenic bacteria and seed disinfectant. Copyright © 2009 Society of Chemical Industry [source]

Evaluation of the environmental fate of thymol and phenethyl propionate in the laboratory

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2008
Dingfei Hu
Abstract BACKGROUND: The natural monoterpenoid pesticides thymol and phenethyl propionate (PEP) are used indoors and outdoors, but their fate in the environment has not been reported. In order better to understand their impact on the environment, water metabolism and soil metabolism studies were conducted with thymol and PEP at a concentration of 10 µg g,1 in water and in soil under laboratory conditions. RESULTS: Dissipation half-lives of thymol and PEP were 16 and 5 days in water and 5 and 4 days in soil. 2-Phenylethanol and 2-(4-hydroxyphenyl)ethanol were detected as primary degradation products of PEP. Over time, a considerable volatilization loss of thymol, but not of phenethyl propionate, was found in the 1 month study under the experimental conditions used. Less than 6% of thymol and PEP were detected as bound residues, and less than 3% were mineralized during the 30 day study. CONCLUSION: In order to maximize the pesticidal effect, more attention should be paid to the temperature for thymol than for PEP when they are being applied, owing to the high volatility of the former. Thymol and PEP pose low risks to the ecosystem because of their rapid dissipation and low bound residues in the environment. Copyright © 2008 Society of Chemical Industry [source]

Antispasmodic activity of extracts and compounds of Acalypha phleoides Cav.,

PHYTOTHERAPY RESEARCH, Issue 2 2004
Adela Astudillo
Abstract The aerial parts of Acalypha phleoides are usually prescribed in the Mexican traditional medicine for a variety of gastrointestinal complaints. The MeOH,CHCl3 (1:1) extract of the aerial part of A. phleoides showed an inhibitory effect on the gastrointestinal propulsion of a charcoal meal in mice. In isolated guinea-pig ileum, this extract produced a concentration dependent inhibition of the contractions induced by 5-hydroxytryptamine, but it was unable to inhibit the contractions elicited by acetylcholine, histamine, KCl and BaCl2. This extract produced also a concentration dependent inhibition of the spontaneous pendular movement of the isolated rabbit jejunum. This inhibitory activity was partially blocked by propranolol. The essential oil, obtained from the aerial part of this plant, was more potent than the MeOH,CHCl3 (1:1) extract in inhibiting the spontan-eous pendular movement of the rabbit jejunum. Thymol, camphor and , -terpinene were identi,ed from the essential oil by GC-MS. These monoterpenes showed antispasmodic activity in the rabbit jejunum preparation, thymol was the most active compound, followed by camphor and , -terpinene. Thymol and camphor in high concentrations also showed tracheal relaxant properties, but , -terpinene did not. These in vivo and in vitro results tend to support the traditional use of A. phleoides as an antispasmodic agent. Copyright © 2004 John Wiley & Sons, Ltd. [source]

THE ANTIBACTERIAL EFFECT OF CINNAMALDEHYDE, THYMOL, CARVACROL AND THEIR COMBINATIONS AGAINST THE FOODBORNE PATHOGEN SALMONELLA TYPHIMURIUM

Thymol analogues with antioxidant and L-type calcium current inhibitory activity

Volatile components of Thymus vulgaris L. from wild-growing and cultivated plants in Jordan

FLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2007
M. Hudaib
Abstract The composition of the essential oil hydrodistilled from the aerial parts of Thymus vulgaris L. grown in Jordan has been determined by GC and GC,MS. Variations in oil composition and yield between cultivated and wild-growing plants collected from different localities, at different altitudes, have been also evaluated. Higher oil yields were observed in plants growing wild (3.7,5.6% of dried material) than in cultivated plants (1.1,2.0%), and those collected from the Mshaqar region, in the middle of Jordan and at the highest altitude, were the richest in oil (,5.4%). Generally, the oil was characterized by marked levels of phenolic monoterpenoids (mainly thymol and carvacrol) in the range 70.8,89.0%. High levels of the monoterpenoid hydrocarbons p -cymene (3.4,8.2%) and , -terpinene (1.6,7.7%) were also observed. Other major components were 1,8-cineole (up to 2.1%), , -thujone (up to 1.2%), camphor (up to 1.1%) and , -caryophyllene (0.2,2.8%). With the exception of plants growing wild in the Ramtha region, in the far north of Jordan, carvacrol was found as the principal phenol of all other oils (50.6,86.1%) and was dominant (>85%) in wild plant oils. The oil from Ramtha was characterized by the highest level of thymol (,63.8%) as the dominant phenol and was most abundant in p -cymene (8.2%), 1,8-cineole (2.1%) and , -terpinene (7.7%). In addition to assigning carvacrol or thymol chemotypes to the plant, the high content of active monoterpenoid phenols strongly suggests a potential use of Jordanian thyme oil in cough products and antimicrobial,herbal drug combinations. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Composition and antimicrobial activity of the essential oil of Micromeria cristata and Micromeria juliana

FLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2006
Gordana Stojanovi
Abstract The chemical composition of the essential oil of Micromeria cristata and Micromeria juliana was determined by GC-MS analysis. Among the 36 identified compounds of the M. cristata essential oil, isoborneol (11.3%), borneol (8.5%), verbenone (8.2%), 10- epi - , -cadinol and thujan-3-ol, were found to be major components. The main constituents of the M. juliana oil were verbenol (11.8%), thymol (10.8%), caryophyllene oxide (10.5%), borneol (9.3%) and myrtenal (7.1%). The in-vitro antimicrobial activity of the ethanolic solution of the essential oils was investigated by the disk diffusion method with ampicillin as the standard antibiotic against six microorganisms (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella enteritidis and Aspergillus niger). At 1:20 dilution the activity of both oils was moderate while at 1:40 dilution the oils showed weak or no activity. Copyright © 2005 John Wiley & Sons, Ltd. [source]

Analysis of the essential oil of algerian Hypericum perfoliatum (L)

FLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2005
O. Touafek
Abstract The hydrodistilled essential oil of Hypericum perfoliatum (Clusiaceae), grown at Jijel (north-eastern Algeria), was analysed by GC,MS; 35 components, representing 96% of the oil, have been identified, with thymol (22.10%), T-cadinol (18.5%) and 4,5-dimethyl-2-ethylphenol (13%) as the main constituents. Copyright © 2005 John Wiley & Sons, Ltd. [source]

Studies of Mediterranean oregano populations,V.

FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005
Chemical composition of essential oils of oregano: Origanum syriacum L. var. bevanii (Holmes) Ietswaart, Israel, O. syriacum L. var. sinaicum (Boiss.) Ietswaart, O. syriacum L. var. syriacum from Lebanon
Abstract Essential oils extracted by steam extraction were analysed by GC and GC-MS. Most of the populations corresponded to a carvacrol chemotype. We show in Origanum syriacum var. bevanii and O. syriacum var. syriacum the existence of thymol, thymol-carvacrol and carvacrol-thymol chemotypes not hitherto described in these species. Copyright © 2004 John Wiley & Sons, Ltd. [source]

Composition of the volatile oil of Thymus transcaspicus Klokov from Iran

FLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2002
R. Miri
Abstract Thymus is one of the most important genera with regard to the number of species within the family Lamiaceae. The essential oil of Thymus transcaspicus Klokov (Lamiaceae) from Iran was isolated by hydrodistillation in 0.9% yield. The chemical composition of the essential oil was examined by GC and GC,MS. Forty-seven compounds were identified, representing 99.5% of the total oil. The main compounds were thymol (56.4%), ,-terpinene (7.7%), carvacrol (7.6%) and p -cymene (6.3%). Copyright © 2002 John Wiley & Sons, Ltd. [source]

The Egyptian Eucalyptus camaldulensis var. brevirostris: chemical compositions of the fruit volatile oil and antioxidant activity

FLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2002
Ahmed H. El-Ghorab
Abstract The fruit volatile oil of E. camaldulensis var. brevirostris was isolated by hydrodistillation and thereafter the fruit marc was extracted by ethanol. The volatile oil obtained was subjected to analysis using gas chromatography,mass spectrometry. Thirty-eight volatile components were identified. The main volatile compounds in the fruit volatile oil were: aromadendrene (17.99%), ,-pinene (12.68%), p -cymenene (5.39%), ,-gurjunene (6.65%), cubenol (9.23%), thymol (1.62%) and p -cymen-7-ol (0.73%). The volatile components were classified into four groups: monoterpenes (20.6%), sesquiterpenes (33.8%), light-oxygenated (8.1%) and heavily-oxygenated (37.6%) compounds. The results showed that the concentration of sesquiterpenes and heavily-oxygenated compounds were higher than the other two classes. The main compound in the ethanol extract of fruit of E. camaldulensis was isolated by semi-preparative HPLC and identified as ellagic acid. The antioxidant activities of the fruits volatile oil and the ethanol extract as well as that of the tree bark were evaluated by the thiocyanate method. The ethanol extract of Eucalyptus fruit exhibited considerable activity compared with butylated hydroxyanisole (BHA) and tertiary butylated hydroquinone (TBHQ). The high inhibitory effect of the ethanol extract of fruit upon linoleic acid after 12 days might be related to the higher ellagic acid content. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Analysis of the essential oil of Lippia graveolens HBK from El Salvador,

FLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2001
Gaston Vernin
Abstract Essential oils from two samples of Lippia graveolens HBK (South American or Mexican oregano, common in El Salvador), were obtained by hydrodistillation and studied by GC and GC,MS. Forty-five compounds, constituting 92,93% of the oil, were identified. The two major components in both samples were carvacrol (71% and 34.6%, respectively) and thymol (5,7%, respectively). In addition, two unusual isomers, 2-isopropyl-4-methylphenol and 4-isopropyl-2-methylphenol, were found and identified by comparison with mass spectral data and retention indices and tentatively synthesized. Copyright © 2001 John Wiley & Sons, Ltd. [source]

Pharmacokinetics and bioavailability of an essential oil compound (thymol) after oral administration

FOCUS ON ALTERNATIVE AND COMPLEMENTARY THERAPIES AN EVIDENCE-BASED APPROACH, Issue 1 2001
G Schindler
[source]

Combined effects of thymol, carvacrol and grapefruit seed extract on lipid oxidation and colour stability of poultry meat preparations

Thymol and modified atmosphere packaging to control microbiological spoilage in packed fresh cod hamburgers

SPME/GC/MS and sensory flavour profile analysis for estimation of authenticity of thyme honey

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 2 2007
Demet Manna
Summary Volatiles of six commercially obtained thyme honey samples and a pure thyme honey sample were extracted and analysed by Solid phase micro extraction (SPME)/Gas chromatography (GC)/Mass spectrometry (MS) procedure. Excess amount of volatiles such as thymol (trace) and carvacrole (0.66%) that originate from thyme plants indicated adulteration by thyme essential oil in one of the commercial samples. Sensory flavour profile analysis showed that the flavour of pure thyme honey sample consisted of: sweet, honey, lilac, bitter almond, thyme, violet, waxy, sour, ginger, caramel and rose characters. Adulterated honey was detected to be the sweetest sample involving intense thyme flavour without honey character. 3,4,5-Trimethoxybenzaldehyde which is a volatile not found in other unifloral honeys, seems to be a possible marker, but further studies with certified thyme honey samples are necessary in order to confirm the utility of this compound in estimation of authenticity. [source]

Effects of thymol and diphenyliodonium chloride against Campylobacter spp. during pure and mixed culture in vitro

JOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2009
R.C. Anderson
Abstract Aims:, To determine if the purported deaminase inhibitors diphenyliodonium chloride (DIC) and thymol reduce the growth and survivability of Campylobacter. Methods and Results:, Growth rates of Campylobacter jejuni and Camp. coli were reduced compared to unsupplemented controls during culture in Muellar,Hinton broth supplemented with 0·25 ,mol DIC or thymol ml,1 but not with 0·01 ,mol monensin ml,1 or 1% ethanol. Recovery of Camp. jejuni and Camp. coli was reduced >5 log10 CFU from controls after 24 h pure culture in Bolton broth supplemented with 0·25 or 1·0 ,mol DIC ml,1 or with 1·0 ,mol thymol ml,1. Similarly, each test Campylobacter strain was reduced >3 log10 CFU from controls after 24 h mixed culture with porcine faecal microbes in Bolton broth supplemented with 0·25 or 1·0 ,mol DIC ml,1 or with 1·0 ,mol thymol ml,1. Treatments with 0·25 ,mol thymol ml,1, 0·01 ,mol monensin ml,1 or 1% ethanol were less effective. Ammonia production during culture or incubation of cell lysates was reduced by 0·25 or 1·0 ,mol DIC ml,1 but only intermittently reduced, if at all, by the other treatments. Conclusions:, Diphenyliodonium chloride and thymol reduced growth, survivability and ammonia production of Camp. jejuni and Camp. coli. Significance and Impact of the Study:, Results suggest a potential physiological characteristic that may be exploited to develop interventions. [source]

Combination of a urease inhibitor and a plant essential oil to control coliform bacteria, odour production and ammonia loss from cattle waste

In vitro assessment of antimicrobial activity of carvacrol, thymol and cinnamaldehyde towards Salmonella serotype Typhimurium DT104: effects of pig diets and emulsification in hydrocolloids

JOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2006
W. Si
Abstract Aims:, To determine the effect of pig diets in vitro on the antimicrobial activity of carvacrol, thymol and cinnamaldehyde, and to identify an emulsifier/stabilizer that can stabilize the essential oil (EO) components in aqueous solution and retain their antimicrobial activity in the presence of the diets. Methods and Results:, Emulsification of essential oil components with hydrocolloid solution was achieved by blending with a Polytron. Antimicrobial activity was measured through in vitro assays to determine the inhibition of bacterial growth by measuring the optical density at 600 nm or plating on nutrition agar after incubation of the mixtures of an EO component with the culture of Salmonella serotype Typhimurium DT104 in the presence or absence of pig diets. The results generated through the in vitro assays indicated that pig diets were able to abolish the antimicrobial activity of EOs. Xanthan, fenugreek and yellow mustard gums were the best in forming stable emulsions of five different EO components among ten different plant polysaccharides and surfactants examined. Emulsification of all the EO components in the fenugreek gum solution did not alter their antimicrobial activity. However, the antimicrobial activity of geraniol was significantly reduced when emulsified with other polysaccharides and surfactants. Both fenugreek and xanthan gum solutions were unable to protect the antimicrobial activity of carvacrol and thymol when mixed with the diets. Although cinnamaldehyde required no emulsification, but a high concentration (equivalent to at least three times of minimum bactericidal concentration for cinnamon oil) to inhibit Salmonella growth significantly in the presence of the diets, emulsification in fenugreek gum appeared to be essential for cinnamaldehyde solution to retain its antimicrobial activity during storage. Conclusions:, The diets for newly weaned pigs were a significant factor limiting the antimicrobial activity of EOs and their components. Cinnamaldehyde required a high concentration to retain its antimicrobial activity in the diets, in addition to its requirement for emulsification to stabilize its activity during the storage. Significance and Impact of the Study:, The assay with the diets used in this study for measuring the antimicrobial activity can be used in vitro for rapid and effective screening of potential antimicrobials for swine production. This study has identified polysaccharides that are able to stabilize EO component solutions. It has also identified cinnamaldehyde for further in vivo studies that may have potential in future application in controlling Salmonella and possibly other enteric pathogens in swine production. [source]

Suitability of bifidobacteria and thymol as biopreservatives in extending the shelf life of fresh packed plaice fillets

JOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2005
C. Altieri
Abstract Aims:, The present study was aimed to evaluate the microbiological and sensory characteristics of biopreserved packed fresh plaice (Pleuronectes platessa), during storage. Methods and Results:, Fish samples were treated with a Bifidobacterium bifidum strain and thymol as preservatives, stored at different temperatures (4 and 12°C) and package atmospheres (in air, under vacuum, modified atmosphere). Data about the total viable count (TVC) were used to predict the shelf life of the fish fillets as affected by the preservatives used and the storage conditions. Data obtained revealed that B. bifidum could perform an efficient synergy with thymol, in controlling the hygiene biological markers. Besides, the tested bifidobacterial species, combined with low storage temperature and anoxia/hypoxia, showed a great efficacy against the main fresh packaged fish spoilage species (Pseudomonas spp., Photobacterium phosphoreum). Conclusions:, The studied technique could be considered effective in fresh fish spoilage control. Significance and Impact of the Study:, Great interest is developing on food biopreservation, because of the ever increasing needs to protect consumers' and environment's health, and to revalorize some important food characteristics, such as naturalness and authenticity, without leaving the safety aside. [source]

Activity and mechanisms of action of selected biocidal agents on Gram-positive and -negative bacteria

JOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2003
S.E. Walsh
Abstract Aims: This study investigates the antimicrobial activity and mode of action of two natural products, eugenol and thymol, a commonly utilized biostatic agent, triclocarban (TCC), and two surfactants, didecyldimethylammonium chloride (DDDMAC) and C10,C16 alkyldimethyl amine N -oxides (ADMAO). Methods and Results: Methods used included: determination of minimum inhibitory concentrations (MICs), lethal effect studies with suspension tests and the investigation of sub-MIC concentrations on growth of E. coli, Staph. aureus and Ps. aeruginosa using a Bioscreen microbiological analyser. Leakage of intracellular constituents and the effects of potentiating agents were also investigated. Only DDDMAC was bactericidal against all of the organisms tested. Eugenol, thymol and ADMAO showed bacteriostatic and bactericidal activity, but not against Ps. aeruginosa. TCC was only bacteristatic against Staph. aureus, but like the other agents, it did affect the growth of the other organisms in the Bioscreen experiments. All of the antimicrobial agents tested were potentiated by the permeabilizers to some extent and leakage of potassium was seen with all of the agents except TCC. Conclusions: DDDMAC was bactericidal against all organisms tested and all compounds had some bacteriostatic action. Low level static effects on bacterial growth were seen with sub-MIC concentrations. Membrane damage may account for at least part of the mode of action of thymol, eugenol, DDDMAC and ADMAO. Significance and Impact of the Study: The ingredients evaluated demonstrated a range of bactericidal and bacteriostatic properties against the Gram-negative and -positive organisms evaluated and the membrane (leakage of intracellular components) was implicated in the mode of action for most (except TCC). Sub-MIC levels of all ingredients did induce subtle effects on the organisms which impacted bacterial growth, even for those which had no true inhibitory effects. [source]

STRATEGIES FOR PROLONGING THE SHELF LIFE OF MINCED BEEF PATTIES

JOURNAL OF FOOD SAFETY, Issue 1 2009
MATTEO ALESSANDRO DEL NOBILE
ABSTRACT The study of different strategies for prolonging the shelf life of fresh minced beef patties was addressed in this work. Fresh minced beef was supplemented with thymol (THY) at levels of 250, 500 and 750 mg per kg of ground beef. Treated samples were packed using a high barrier film and stored in refrigerated conditions (4C) under ordinary atmosphere packaging and modified atmosphere packaging (MAP) conditions for 16 days. The microbiological quality decay kinetic was determined by monitoring the following microorganisms: Enterobacteriaceae, Pseudomonas spp., lactic acid bacteria, Brochothrix thermosphacta, coliforms and total psychrotrophic viable count. Results show that THY, working alone, was effective on coliforms and Enterobacteriaceae, whereas it does not seem to inhibit to a great extent the growth of the other microbial populations. On the other hand, an increased amount of THY, under MAP conditions, had better effects on the product quality, with a consequent prolongation of the shelf life. PRACTICAL APPLICATIONS Great interest is developing in food bio-preservation, because of the ever-increasing needs to protect consumers' health and to valorize the naturalness and safety of food products. However, very few works have been carried out on the applications of bio-preservatives to extend the shelf life of fresh meat products. This study, therefore, was mainly initiated to evaluate the possibility of extending the shelf life of packed fresh meat patties by a combination of thymol (THY) to other extrinsic factors such as storage temperatures and modified atmosphere during packaging. Interesting results were obtained suggesting that THY can perform an efficient synergy with modified atmosphere conditions and could be advantageously utilized by the meat industry. [source]

CHEMICAL CHARACTERIZATION AND ANTIFUNGAL ACTIVITY OF ORIGANUM ONITES L. ESSENTIAL OILS AND EXTRACTS

JOURNAL OF FOOD SAFETY, Issue 1 2009
MIHRIBAN KORUKLUOGLU
ABSTRACT Essential oils (EOs) and extracts (methanol, acetone and diethyl ether) of fresh and dried oregano (Origanum onites L.) were used to determine the antifungal effect on Alternaria alternata, Aspergillus flavus (two strains), Aspergillus niger (two strains), Aspergillus parasiticus, Fusarium semitectum, Fusarium oxysporum, Mucor racemosus and Penicillium roqueforti by disk diffusion methods. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of all samples were determined. The antifungal activity of the fresh herb was greater than that of the dried herb. MIC values for fresh and dried methanol extracts were 150,950 µg/mL and 750,950 µg/mL, respectively. MFC values for methanol extracts were determined between 300 and 1200 µg/mL for fresh oregano and between 750 and 1100 µg/mL for dried oregano. The EOs of fresh and dried oregano totally inhibited test fungi. EOs produced the lowest MIC and MFC values: 8.5 µg/mL and 9.0 µg/mL, respectively (P < 0.005). The highest extract activity was exhibited by fresh oregano against A. alternata (24 mm) followed by P. roqueforti (20 mm). The greatest total antifungal effect was observed from methanol extracts. The chemical composition of fresh oregano EO and extracts was examined using gas chromatography-mass spectrometry (GC-MS). Over 80 volatiles were detected, of which 42 were positively identified by matching both MS fragmentation patterns with standardized retention characteristics. p-Cymene, thymol and carvacrol were the most prominent, followed by ,-pinene, camphor and borneol. PRACTICAL APPLICATIONS In the past decade interest in natural antimicrobial plant extracts has been growing. Various plants have historically been used for the purposes of food preservation and flavor enhancement as well as medicinal purposes. An example is oregano, the leafy part of the plant belonging to the Labiatae family. It has been used to improve the flavor and the organoleptic properties of many foods from numerous cultures. It has also been used to prolong the storage life of foods probably because of antifungal properties. The preservative nature of fresh oregano has been employed in many food applications, including meat and fish products, as well as in pharmaceuticals, alternative medicines and natural therapies. [source]

THE ANTIBACTERIAL EFFECT OF CINNAMALDEHYDE, THYMOL, CARVACROL AND THEIR COMBINATIONS AGAINST THE FOODBORNE PATHOGEN SALMONELLA TYPHIMURIUM

Effects of 4-piperidinomethyl-2-isopropyl-5-methylphenol on oxidative stress and calcium current

JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 9 2005
Mei-Han Huang
4-Piperidinomethyl-2-isopropyl-5-methylphenol (THPI) was synthesized by reaction of thymol with piperidine and formaldehyde. The biological effect of THPI on superoxide anion scavenging activity, antiplatelet activity and calcium current inhibition were investigated. THPI (50 ,m) was shown to be a scavenger of superoxide radicals in human neutrophils stimulated with N -formyl-Met-Leu-Phe (66% inhibition). Since superoxide anions are essential for platelet aggregation and L-type Ca2+ -channel activity, we further found that THPI inhibited platelet aggregation induced by arachidonic acid (IC50 46.80 ± 6.88 ,m). The effect of THPI on Ca2+ current in NG108,15 cells was investigated using the whole-cell voltage-clamp technique. THPI inhibited voltage-dependent L-type Ca2+ current (ICa,L). The IC50 value of THPI-induced inhibition of ICa,L was 3.60 ± 0.81 ,m. THPI caused no change in the overall shape of the current-voltage relationship of ICa,L. This indicates that THPI is an inhibitor of ICa,L in NG108,15 cells. Therefore, the channel-blocking properties of THPI may contribute to the underlying mechanism by which it affects neuronal or neuroendocrine function. Furthermore, no significant cytotoxic effects of THPI (0.3,50 ,m) were observed in NG108,15 cells. The results indicate that THPI is a potential reactive oxygen species scavenger and may prevent platelet aggregation or inhibit L-type Ca2+ -channel activity, possibly by scavenging reactive oxygen species. [source]