Impact of Phytochemicals on Viability and Cereulide Toxin Synthesis in Bacillus cereus Revealed by a Novel High-Throughput Method, Coupling an AlamarBlue-Based Assay with UPLC-MS/MS.

Due to its food-poisoning potential, Bacillus cereus has attracted the attention of the food industry. The cereulide-toxin-producing subgroup is of particular concern, as cereulide toxin is implicated in broadscale food-borne outbreaks and occasionally causes fatalities. The health risks associated with long-term cereulide exposure at low doses remain largely unexplored. Natural substances, such as plant-based secondary metabolites, are widely known for their effective antibacterial potential, which makes them promising as ingredients in food and also as a surrogate for antibiotics. In this work, we tested a range of structurally related phytochemicals, including benzene derivatives, monoterpenes, hydroxycinnamic acid derivatives and vitamins, for their inhibitory effects on the growth of B. cereus and the production of cereulide toxin. For this purpose, we developed a high-throughput, small-scale method which allowed us to analyze B. cereus survival and cereulide production simultaneously in one workflow by coupling an AlamarBlue-based viability assay with ultraperformance liquid chromatography-mass spectrometry (UPLC-MS/MS). This combinatory method allowed us to identify not only phytochemicals with high antibacterial potential, but also ones specifically eradicating cereulide biosynthesis already at very low concentrations, such as gingerol and curcumin.

HPLC-Analysis, Biological Activities and Characterization of Action Mode of Saudi Marrubium vulgare against Foodborne Diseases Bacteria.

The present study aims to evaluate the chemical composition, metabolites secondary and pharmacology activities of methanolic extract of Marrubium vulgare collected from King Saudi Arabia. Moreover, the primary mode of action of the tested extract was studied here for the first time against E. coli and L. monocytogenes. HPLC analysis shows that the major components in the tested extract are luteolin-7-O-d-glucoside, ferulic acid and premarrubiin. Obtained data demonstrated that the investigated extract was richer in phenol (26.8 ± 0.01 mg/GAE g) than in flavonoids (0.61 ± 0.05 mg EC/mL). In addition, the methanolic extract showed an important antioxidant capacity against the DPPH (IC50 = 35 ± 0.01 µg/mL) and ABTS (IC50 = 25 ± 0.2 µg/mL) radical scavenging and a strong inhibition of acetylcholinesterase enzyme with an IC50 value corresponding to 0.4 mg/mL. The antibacterial activity demonstrated that the evaluated extract had significant activity against both Gram-positive and Gram-negative bacteria. The effect of time on cell integrity on E. coli and L. monocytogenes determined by time-kill and bacteriolysis tests showed that the M. vulgare extract reduced the viability of both strains after 8 and 10 h and had a bacteriolytic effect against two different categories of bacteria, Gram-positive and negative, which are not of the same potency. Based on obtained data, it can be concluded that Saudi M. vulgare has a high pharmacological importance and can be used in preparation of food or drugs.

Essential Oil of Algerian Eryngium campestre: Chemical Variability and Evaluation of Biological Activities.

The chemical composition of essential oils extracted from aerial parts of Eryngium campestre collected in 37 localities from Western Algeria was characterized using GC-FID and GC/MS analyses. Altogether, 52 components, which accounted for 70.1 to 86.8% of the total composition oils were identified. The main compounds were Germacrene D (0.4-53.4%), Campestrolide (1.6-35.3%), Germacrene B (0.2-21.5%), Myrcene (0.1-8.4%), α-Cadinol (0.2-7.6%), Spathulenol (0.1-7.6%), Eudesma-4(15)-7-dien-1-ß-ol (0.1-7.6%) and τ-Cadinol (0.3-5.5%). The chemical compositions of essential oils obtained from separate organs and during the complete vegetative cycle of the plant were also studied. With the uncommon 17-membered ring lactone named Campestrolide as the main component, Algerian E. campestre essential oils exhibited a remarkable chemical composition. A study of the chemical variability using statistical analysis allowed the discrimination of two main clusters according to the geographical position of samples. The study contributes to the better understanding of the relationship between the plant and its environment. Moreover, the antimicrobial activity of the essential oil was assessed against twelve strains bacteria and two yeasts involved in foodborne and nosocomial infections using paper disc diffusion and dilution agar assays. The in vitro study demonstrated a strong activity against Gram-positive strains such as S. aureus, B. cereus, and E. faecalis. The cytotoxicity and antiparasitic activities (on Lmm and Tbb) of the collective essential oil and one sample rich in campestrolide, as well as some enriched fractions or fractions containing other terpenic compounds, were also analyzed. Campestrolide seems to be one compound responsible for the cytotoxic and antileishmanial effect, while myrcene or/and trans-ß-farnesene have a more selective antitrypanosomal activity.

Antimicrobial properties of rosin acids-loaded nanoparticles against antibiotic-sensitive and antibiotic-resistant foodborne pathogens.

Rosin acids (RA) from coniferous trees are used in folk medicine for healing various skin infections. Despite the antimicrobial potential of RA, their poor solubility in aqueous media may limit their use. In this work RA-loaded polyethylene glycol-poly(lactic-co-glycolic acid) nanoparticles (RA-NPs) with enhanced antimicrobial properties against foodborne bacterial pathogens were produced. RA-NPs were prepared by solvent displacement technique and characterized for relevant colloidal features by dynamic light scattering, laser Doppler anemometry and transmission electron microscopy. Association of RA to NPs occurred with high yields (86% w/w). RA and RA-NPs (∼130 nm) were strongly active against antibiotic-sensitive Gram + pathogens, i.e. Clostridium perfringens, Listeria monocytogenes and antibiotic-resistant Staphylococcus aureus. However, both failed in inhibiting the growth of Gram - pathogens (Campylobacter jejuni, Campylobacter coli, Escherichia coli and Salmonella enterica). Association to NPs enhanced the antimicrobial activity of RA. MIC, IC50, IC90, and MBC values of RA-NPs were ten-times lower than RA. RA-NPs did not change the intrinsic toxicity potential of RA. This is the first study on the enhancement of the antimicrobial activity of RA when associated to nanocarriers. This approach may be an effective strategy to produce aqueous-based RA solutions with enhanced antimicrobial activity against antibiotic-sensitive and antibiotic-resistant Gram + pathogens.

Antimicrobial Effect of Garlic (Allium sativum) and Thyme (Zataria multiflora Boiss) Extracts on Some Food Borne Pathogens and Their Effect on Virulence Gene Expression.

The incrementing scope of pathogenic resistance to antibiotics has encouraged the search for antivirulence natural extracts. Therefore, our study designed to demonstrate the antimicrobial activity of an aqueous-garlic and thyme oil extracts against Gram-positive (Staphylococcus aureus) and Gram-negative (Salmonella spp.) bacteria by evaluating the influence of sub-inhibitory concentrations on the expression of the most critical virulence genes of the tested isolates. The antibacterial potential of both herbs was checked by the agar well diffusion method and minimum inhibitory concentration (MIC) assay. Interestingly, all isolates were inhibited by both extracts up to 50% concentration. Also, the MIC values of garlic extract (0.125-1µg/ml) against Salmonella isolates were lower than the values of thyme extract (0.5- 8µg/ml). But in S. aureus isolates, the MIC values of thyme extract (0.25- 2µg/ml) were the lowermost. Conventional PCR investigated that all S. aureus isolates carried the hlg (hemolysin) and icaA (intracellular adhesion) genes, but only six Salmonella isolates (three S. typhimurium and one each of S. kentucky, S. anatum, and S. lagos) had both the sopB (Salmonella outer protein B) and mgtC (membrane protein) genes. Real-time RT-PCR assays were performed to evaluate the extract's effect on the virulence genes. The thyme-oil extract has significantly repressed S. aureus virulence genes expression more than aqueous-garlic extract, which later one has effectively more than thyme-oil extract in downregulating the Salmonella virulence genes. In conclusion, garlic and thyme extracts can be used not only as a flavor, but also as potential antimicrobial agents against Gram-positive and negative bacteria.

Chemical composition and antibacterial activity of oils from Chrysicthys nigrodigitatus and Hepsetus odoe, two freshwater fishes from Yabassi, Cameroon.

BACKGROUNDS: Oils of fish origin are a very rich source of Omega - 3 and Omega - 6 fatty acids. They have been suggested to provide numerous health benefits for humans involving antimicrobial properties. Chrysichthys nigrodigitatus and Hepsetus odoe are two fishes well known in Cameroon. The chemical composition and the antibacterial activity of these fishes derived oils are unknown. The study was designed to valorise C. nigrodigitatus and H.s odoe oils activity against food poisoning bacteria. METHODS: Oils were extracted by pressing and maceration methods. Their quality was assessed by analysing quality indexes including peroxides, acid, iodine, anisidine and thiobarbituric acid values. Chemical analysis was established by gas chromatography coupled to flame ionization detector. Antibacterial activity was evaluated by broth microdilution method. RESULTS: C. nigrodigitatus oil obtained by maceration exhibited highest acid (7.33 ± 0.00 mg KOH/g), anisidine (34.5 ± 1.84) and thiobarbituric acid (7.50 ± 0.30 µmol MDA/Kg) values compared to that obtained by pressing method (9.13 ± 0.64 and 6.72 ± 0.34 µmol MDA/Kg) respectively. H. odoe oil obtained by pressing method showed highest peroxide value (6.22 ± 1.31 meq O2/kg). Oil chemical analysis revealed long chain polyunsaturated fatty acids of the ω-3 family: linolenic acid (C18:3); eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) and ω-6 family; arachidonic acid (C20:4). In addition, C. nigrodigitatus oil obtained by pressing and maceration methods showed Minimum Inhibitory Concentrations (MIC) values ranging from 32 to 64 mg/ml. H. odoe oil obtained by pressing method revealed MIC values ranging between 8 and 64 mg/ml. CONCLUSIONS: C. nigrodigitatus and H. odoe oils have activity against food poisoning bacteria, due to their chemical composition.

Efficacy of Ceftriaxone, Cefepime, Doxycycline, Ciprofloxacin, and Combination Therapy for Vibrio vulnificus Foodborne Septicemia.

Foodborne Vibrio vulnificus infections are associated with higher rates of sepsis and mortality than wound infections; however, antibiotic efficacy studies have not been performed in foodborne infection models. The efficacies of ceftriaxone, cefepime, doxycycline, ciprofloxacin, and combination therapy were assessed in V. vulnificus intestinal infection in mice in order to model foodborne infections. In accordance with prior studies of cefotaxime, cefepime was synergistic with doxycycline and ciprofloxacin in vitro; combination therapy significantly decreased bacterial growth, by ≥2 log10 units, from that with antibiotic monotherapy (P < 0.01). In vivo, survival rates in the ceftriaxone (50%), doxycycline (79%), and ciprofloxacin (80%) groups were significantly higher than those in the control group (0%) (P < 0.0001). Survival was significantly higher with ceftriaxone-doxycycline (91%) or ceftriaxone-ciprofloxacin (100%) therapy than with ceftriaxone (50%) (P ≤ 0.05). Survival with cefepime-doxycycline (96%) or cefepime-ciprofloxacin (90%) therapy was significantly higher than that with cefepime alone (20%) (P < 0.001). There was no difference in survival between the combination therapy groups. Thus, we conclude that combination therapy was the most effective treatment for foodborne V. vulnificus septicemia. In a septic patient with a recent ingestion of raw seafood, cefepime in combination with doxycycline or ciprofloxacin should be initiated for coverage of resistant Gram-negative organisms and V. vulnificus pending a microbiological diagnosis. Once a diagnosis of foodborne V. vulnificus septicemia is established, treatment can safely transition to ceftriaxone in combination with doxycycline or ciprofloxacin.

Antimicrobial activity of eugenol and essential oils containing eugenol: A mechanistic viewpoint.

Eugenol is a hydroxyphenyl propene, naturally occurring in the essential oils of several plants belonging to the Lamiaceae, Lauraceae, Myrtaceae, and Myristicaceae families. It is one of the major constituents of clove (Syzygium aromaticum (L.) Merr. & L.M. Perry, Myrtaceae) oil and is largely used in both foods and cosmetics as a flavoring agent. A large body of recent scientific evidence supports claims from traditional medicine that eugenol exerts beneficial effects on human health. These effects are mainly associated with antioxidant and anti-inflammatory activities. Eugenol has also shown excellent antimicrobial activity in studies, being active against fungi and a wide range of gram-negative and gram-positive bacteria. The aim of this review is to analyze scientific data from the main published studies describing the antibacterial and antifungal activities of eugenol targeting different kind of microorganisms, such as those responsible for human infectious diseases, diseases of the oral cavity, and food-borne pathogens. This article also reports the effects of eugenol on multi-drug resistant microorganisms. On the basis of this collected data, eugenol represents a very interesting bioactive compound with broad spectrum antimicrobial activity against both planktonic and sessile cells belonging to food-decaying microorganisms and human pathogens.

Antimicrobial resistance of Salmonella spp. isolated from food

This review summarizes current data on resistance among Salmonella spp. isolates of food origin from countries in different regions of the world. The mechanisms of resistance to different groups of antimicrobial compounds are also considered. Among strains resistant to quinolones and/or fluoroquinolones the most prevalent mechanism is amino acid substitutions in quinolone resistance-determining region (QRDR) of genes gyrA, parC but mechanism of growing importance is plasmid-mediated quinolone resistance (PMQR) associated with genes qnrA, qnrB, qnrC, qnrD, qnrS but frequency of their detection is different. Resistance to sulfonamides is mostly associated with genes sul1 and sul2, while resistance to trimethoprim is associated with various variants of dhfr ( dfr) genes. Taking into account Salmonella spp. strains isolated from food, resistance to ß-lactams is commonly associated with ß-lactamases encoding by blaTEM genes. However strains ESBL and AmpC ­ positive are also detected. Resistance to aminoglicosides is commonly result of enzymatic inactivation. Three types of aminoglycoside modifying enzyme are: acetyltransferases (AAC), adenyltransferases (ANT) and phosphotransferases (APH). Resistance to tetracyclines among Salmonella spp. isolated from food is most commonly associated with active efflux. Among numerous genetic determinants encoding efflux pumps tetA, tetB, tetC, tetD, tetE and tetG are reported predominatingly. One of the most common mechanisms of resistance against chloramphenicol is its inactivation by chloramphenicol acetyltrasferases (CATs), but resistance to this compound can be also mediated by chloramphenicol efflux pumps encoded by the genes cmlA and floR. It is important to monitor resistance of Salmonella isolated from food, because the globalization of trade, leading to the long-distance

Inhibitory Effects of Gallic Acid Isolated from Caesalpinia mimosoides Lamk on Cholangiocarcinoma Cell Lines and Foodborne Pathogenic Bacteria.

Gallic acid was isolated from Caesalpinia mimosoides Lamk and the structure s identified based on spectroscopic analysis and comparison with authentic compound. In this study we compared the ability of natural gallic acid (nGA) and commercial gallic acid (cGA) to inhibit the proliferation of cholangiocarcinoma cell lines (M213, M214) and foodborne pathogenic bacteria (Salmonella spp. and Plesiomonas shigelloides). Both nGA and cGA had the same inhibitory effects on cell proliferation by inducing apoptosis of cholangiocarcinoma cell lines. In addition, nGA inhibited growth of foodborne pathogenic bacteria in the same manner as cGA. Our results suggest that nGA from Caesalpinia mimosoides Lamk is a potential anticancer and antibacterial compound. However, in vivo studies are needed to elucidate the specific mechanisms involved.

Antimicrobial flavonoids isolated from Indian medicinal plant Scutellaria oblonga inhibit biofilms formed by common food pathogens.

Scutellaria oblonga Benth., a hitherto phytochemically unexplored Indian medicinal folklore plant was extracted with acetone and subjected to chromatography to yield nine flavonoids, for the first time from this plant. Antimicrobial assays were performed against 11 foodborne pathogens, and three molecules (Techtochrysin, Negletein and Quercitin-3-glucoside) depicted significant activity. These molecules were assessed for their rate of antibacterial action using time-kill curves which depicted complete inhibition of most of the bacteria within 12-16 h. The significant biofilm-reducing capability exhibited by these three molecules formed a significant finding of the current study. In most of the experiments, a 90-95% reduction in biofilms was observed. Thus, flavonoids as natural molecules from S. oblonga could be further researched to be used as potent antimicrobial and antibiofilm agents.

Plant compounds enhance the assay sensitivity for detection of active Bacillus cereus toxin.

Bacillus cereus is an important food pathogen, producing emetic and diarrheal syndromes, the latter mediated by enterotoxins. The ability to sensitively trace and identify this active toxin is important for food safety. This study evaluated a nonradioactive, sensitive, in vitro cell-based assay, based on B. cereus toxin inhibition of green fluorescent protein (GFP) synthesis in transduced monkey kidney Vero cells, combined with plant extracts or plant compounds that reduce viable count of B. cereus in food. The assay exhibited a dose dependent GFP inhibition response with ~25% inhibition at 50 ng/mL toxin evaluated in culture media or soy milk, rice milk or infant formula, products associated with food poisonings outbreak. The plant extracts of green tea or bitter almond and the plant compounds epicatechin or carvacrol were found to amplify the assay response to ~90% inhibition at the 50 ng/mL toxin concentration greatly increasing the sensitivity of this assay. Additional studies showed that the test formulations also inhibited the growth of the B. cereus bacteria, likely through cell membrane disruption. The results suggest that the improved highly sensitive assay for the toxin and the rapid inactivation of the pathogen producing the toxin have the potential to enhance food safety.

The anti-dermatophyte activity of Allium hirtifolium Boiss aqueous extract.

In an attempt at demonstrating the efficacy of Allium hirtifolium aqueous extract in control of skin fungal infections as traditional use, we evaluated the anti-dermatophyte activities of A. hirtifolium aqueous extract from bulbs and of ketoconazole against Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum canis, M. gypseum, Trichophyton schoenleinii and Trichophyton verrucosum var. album by food poisoning technique, disc diffusion and micro broth dilution assays. The anti-fungal activity of A. hirtifolium was excellent when it was compared with ketoconazole. The anti-fungal evaluation by food poisoning method showed that A. hirtifolium extract inhibited the growth of dermatophytes dose-dependently. The inhibition zone diameter (IZ) of A. hirtifolium extract (15 µg/disc) was in the range of 28.8 ± 0.31 to 67.7 ± 1.5mm, while ketoconazole (15 µg/disc) had the IZ lower than 13mm. The MIC and MFC values of A. hirtifolium extract were in the range of 0.2-1.7 and 0.4-0.7 µg/mL; respectively. Therefore, A. hirtifolium extract showed a strong anti-fungal activity against human and animal dermatophytes.

Antimicrobial effects of Caulerpa sertularioides extract on foodborne diarrhea-caused bacteria.

AIM: Caulerpa (C.) sertularioides has many therapeutic uses in the practice of traditional medicine in Malaysia. Crude methanolic, diethyl ether extract, ethyl acetate extract and butanolic extract from C. sertularioides were subjected to antimicrobial screening including the three Gram-positive and three Gram-negative diarrhea-caused bacteria. MATERIALS AND METHODS: The antimicrobial activities were studied by using disc diffusion method and broth dilution method. The effect of the extract on the growth profile of the bacteria was examined via time-kill assay. In addition to the bactericidal effects study, microscopic observations using Scanning electron microscopy (SEM) was done to determine the major alterations in the microstructure of Bacillus (B.) subtilis. RESULTS: Ethyl acetate extract demonstrated antibacterial activity towards all the tested bacteria and produced inhibition zone ranging from ≤ 9 mm - ≥ 15 mm. However, all the tested bacteria were resistant to the butanolic extract treatment. B. subtilis growth curve in the presence of the crude methanol extract at MIC showed bacteriostatic. The main abnormalities found from these microscopic observations were morphology alteration of the bacteria cells after exposure to the methanol extract. CONCLUSIONS: Data from this study revealed that C. sertularioides may be potential antimicrobial agents against foodborne Gram-positive and Gram-negative bacteria particularly cause diarrhea, and also food spoilage microorganisms.

Review of the inhibition of biological activities of food-related selected toxins by natural compounds.

There is a need to develop food-compatible conditions to alter the structures of fungal, bacterial, and plant toxins, thus transforming toxins to nontoxic molecules. The term 'chemical genetics' has been used to describe this approach. This overview attempts to survey and consolidate the widely scattered literature on the inhibition by natural compounds and plant extracts of the biological (toxicological) activity of the following food-related toxins: aflatoxin B1, fumonisins, and ochratoxin A produced by fungi; cholera toxin produced by Vibrio cholerae bacteria; Shiga toxins produced by E. coli bacteria; staphylococcal enterotoxins produced by Staphylococcus aureus bacteria; ricin produced by seeds of the castor plant Ricinus communis; and the glycoalkaloid α-chaconine synthesized in potato tubers and leaves. The reduction of biological activity has been achieved by one or more of the following approaches: inhibition of the release of the toxin into the environment, especially food; an alteration of the structural integrity of the toxin molecules; changes in the optimum microenvironment, especially pH, for toxin activity; and protection against adverse effects of the toxins in cells, animals, and humans (chemoprevention). The results show that food-compatible and safe compounds with anti-toxin properties can be used to reduce the toxic potential of these toxins. Practical applications and research needs are suggested that may further facilitate reducing the toxic burden of the diet. Researchers are challenged to (a) apply the available methods without adversely affecting the nutritional quality, safety, and sensory attributes of animal feed and human food and (b) educate food producers and processors and the public about available approaches to mitigating the undesirable effects of natural toxins that may present in the diet.

Antiviral effects of black raspberry (Rubus coreanus) juice on foodborne viral surrogates.

Abstract Human noroviruses (HuNoVs) are the most frequent cause of foodborne viral gastroenteritis, causing approximately 90% of non-bacterial epidemic outbreaks around the world. Rubus coreanus is a species of black raspberry, rich in polyphenols, and known to exert anti-inflammatory, antibacterial, and antiviral activities. In the present study, the antiviral effects of R. coreanus juice (black raspberry [BRB] juice) on foodborne viral surrogates, murine norovirus-1 (MNV-1) and feline calicivirus-F9 (FCV-F9), were compared with those of cranberry juice, grape juice, and orange juice by plaque assays. Among the four juices tested, BRB juice was the most effective in reducing plaques formation of these viruses. Time-of-addition experiments were designed to determine the mechanism of action of BRB juice on MNV-1 and FCV-F9. The maximal antiviral effect of BRB juice against MNV-1 was observed when it was added to RAW 264.7 cells (mouse leukemic monocyte macrophage cell line) simultaneously with the virus. Pre-treatment of either Crandell Reese Feline Kidney cells or FCV-F9 with BRB juice exhibited significant antiviral activity. The inhibition of viral infection by BRB juice on MNV-1 and FCV-F9 probably occurs at the internalization of virions into the cell or the attachment of the viral surface protein to the cellular receptor. The polyphenol components in BRB (i.e., gallic acid and quercetin), however, did not show any activity against these viruses. Our data provide great promise for the utilization of BRB in the prevention of foodborne viral outbreaks.

Antiviral effects of cranberry juice and cranberry proanthocyanidins on foodborne viral surrogates--a time dependence study in vitro.

Cranberry juice (CJ) and cranberry proanthocyanidins (PAC) are widely known for their antibacterial, antiviral, and pharmacological activities. The effect of CJ and cranberry PAC on the infectivity of foodborne viral surrogates, murine norovirus (MNV-1), feline calicivirus (FCV-F9), MS2 (ssRNA) bacteriophage, and ϕX-174 (ssDNA) bacteriophage after 0 min to 1h at room temperature was evaluated. Viruses at titers of ∼5log(10)PFU/ml were mixed with equal volumes of CJ at pH 2.6, CJ at pH 7.0, 0.30 mg/ml CJ PAC, 0.60mg/ml PAC, or water and incubated for 0, 10, 20, 30, 40, 50 min, and 1h at room temperature. Infectivity was determined using standard plaque assays. The viral reduction rates of the four tested viruses were found to vary considerably. Among the tested viruses, FCV-F9 titers were decreased the most by ∼5log(10)PFU/ml within 30 min. MS2 titers were decreased the least by only ∼1log(10)PFU/ml after 1h with CJ at pH 2.6 and 0.30 mg/ml PAC, and ∼0.5log(10)PFU/ml with CJ at pH 7.0 and 0.15 mg/ml PAC. MNV-1 and ϕ-X174 showed comparable titer reductions which was between that of FCV-F9 and MS2. In most cases, viral reduction within the first 10 min of treatment accounted for ≥50% of the total reduction. Transmission electron microscopy on FCV-F9 treated with CJ and PAC revealed structural changes. This study shows potential of using natural bioactive compounds for controlling foodborne viral diseases. Further studies are necessary to elucidate the mechanism of action of CJ components and to understand the differences in viral titer reduction profiles.

Inhibitory effect of the essential oil from Chamaecyparis obtusa on the growth of food-borne pathogens.

In this study, the antibacterial activity of essential oil from Chamaecyparis obtusa (Sieb. et Zucc) leaves and twigs was investigated. The test strains were Klebsiella pneumoniae, Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, Escherichia coli, Legionella pneumophila, and Methicilline-resistant Staphylococcus aureus. Antibacterial activity was estimated by measuring bacterial growth inhibition. Histopathological examination was also performed. C. obtusa oil distinctly inhibited the growth of all test strains and exhibited the strongest antibacterial activity against L. monocytogenes. It was chromatographically divided into several fractions. The fractions were further tested against antibacterial activity and their chemical compositions were analyzed. The fraction containing terpinen-4-ol (TA) showed high antibacterial activity toward all strains tested. Tests with authentic samples showed that TA played a major role in the antibacterial activity of C. obtusa oil, and in a mice test, the oil actively minimized inflammation by S. aureus.

Aquilegia vulgaris L. extract counteracts oxidative stress and cytotoxicity of fumonisin in rats.

Exposure to fumonisins (FB) is known to have toxic and carcinogenic effects in different animal species, and to express toxicity in cells via the induction of oxidative stress. The aim of the current study was to evaluate the protective effects of the ethanol extract of Aquilegia vulgaris L. against the oxidative stress and the genotoxicity using micronucleus assay and random amplified polymorphism DNA (RAPD-PCR) in FB-treated rats. Sixty mature female Sprague-Dawley were divided into six treatment groups and treated for 4 weeks as follow: the control group, the group fed FB-contaminated diet (200 mg/kg diet), the groups treated orally with the extract (5 and 10 mg/kg bw) and the groups fed FB-contaminated diet and treated with the extract at the two doses. The results showed that treatment with FB alone disturbed lipid profile in serum, increases Sa/So ratio, induces micronucleated polychromatic erythrocytes (Mn-PCEs) in bone marrow, increases DNA and RNA in liver accompanied with significant changes in histological picture The extract alone at the two tested doses did not induce any significant changes in the biochemical or histological picture. The combined treatment showed significant improvements in all biochemical, cytogenetic parameters tested and histological pictures in the liver tissues. Moreover, this improvement was more pronounced in the group received the high dose of the extract. It could be concluded that the ethanol extract of A. vulgaris induced its protective effect via the increase in the antioxidant capacity, inhibition of lipid peroxidation and scavenging of free radicals.

Atrioventricular block induced by mad-honey intoxication: confirmation of diagnosis by pollen analysis.

An unusual type of food poisoning, mad-honey intoxication, can be observed in the Black Sea region of Turkey and various other parts of the world. It can occur after ingestion of grayanotoxin-contaminated honey produced from the nectar of Rhododendron ponticum and other plant species, chiefly of the Ericaceae and Sapindaceae families. Mad-honey intoxication can result in severe cardiac complications, such as complete atrioventricular block. The diagnosis is generally reached on the basis of the patient's history of honey intake. In this report, we describe the case of a patient who had mad-honey-related complete atrioventricular block; in this instance, the diagnosis was confirmed by a pollen analysis of the suspect honey.