Chemical composition of the essential oils from the flower, leaf and stem of Lonicera japonica

The essential oils from different aerial parts of Lonicera japonica have been extracted by hydro-distillation and analyzed by gas chromatography and gas chromatography coupled with mass spectrometry. Quantitative and qualitative differences were found between the analyzed plant parts. A total of eighty-nine compounds were identified. The main constituents were (Z,Z)-farnesole (16.2%) and linalool (11.0%) for the flowers fraction, hexadecanoic acid (16.0%) and linalool (8.7%) for the leaves fraction, and hexadecanoic acid (31.4%) for the stems. Monoterpene hydrocarbons were absent from all the oils, and oxygenated sesquiterpenes were not identified in the essential oil of the stem

Diagnostic Methods of Clostridioides difficile Infection and Clostridioides difficile Ribotypes in Studied Sample

Background: Clostridioides (Clostridium) difficile is the most common nosocomial pathogen and antibiotic-related diarrhea in health-care facilities. Over the last few years, there was an increase in the incidence rate of C. difficile infection cases in Slovakia. In this study, the phenotypic (toxigenicity, antimicrobial susceptibility) and genotypic (PCR ribotypes, genes for binary toxins) patterns of C. difficile isolates from patients with CDI were analyzed, from July to August 2016, taken from hospitals in the Horne Povazie region of northern Slovakia. The aim of the study was also to identify hypervirulent strains (e.g., the presence of RT027 or RT176). Methods: The retrospective analysis of biological samples suspected of CDI were analyzed by GDH, anaerobic culture, enzyme immunoassay on toxins A/B, multiplex “real-time” PCR and PCR capillary-based electrophoresis ribotyping, and by MALDI TOF MS. Results: C. difficile isolates (n = 44) were identified by PCR ribotyping, which revealed five different ribotypes (RT001, 011, 017, 081, 176). The presence of hypervirulent RT027 was not identified. The C. difficile isolates (RT001, 011, 081, 176) were susceptible to metronidazole and vancomycin. One isolate RT017 had reduced susceptibility to vancomycin. A statistically significant difference between the most prevalent PCR ribotypes, RT001 and RT176, regarding variables such as albumin, CRP, creatinine, the length of hospitalization (p = 0.175), and glomerular filtration (p = 0.05) was not found. Conclusion: The results of PCR capillary-based electrophoresis ribotyping in the studied samples showed a high prevalence of RT176 and 001

Use of MALDI-TOF MS to Discriminate between Aflatoxin B1-Producing and Non-Producing Strains of <i>Aspergillus flavus</i>

Aflatoxin B1 (AFB1) is one of the most toxic mycotoxins. One of the producers of AFB1 is Aspergillus flavus. Therefore, its rapid identification plays a key role in various sectors of the food and feed industry. MALDI-TOF mass spectrometry is one of the fastest and most accurate methods today. Therefore, the aim of this research was to develop the rapid identification of producing and non-producing strains of A. flavus based on the entire mass spectrum. To accomplish the main goal a different confirmatory MALDI-TOF MS and TLC procedures such as direct AFB1 identification by scraping from TLC plates, A. flavus mycelium, nutrient media around A. flavus growth, and finally direct AFB1 identification from infected wheat and barley grains had to be conducted. In this experiment, MALDI-TOF mass spectrometry with various modifications was the main supporting technology. All confirmatory methods confirmed the presence of AFB1 in the samples of aflatoxin-producing strains of A. flavus and vice versa; AFB1 was not detected in the case of non-producing strains. Entire mass spectra (from 2 to 20 kDa) of aflatoxin-producing and non-producing A. flavus strains were collected, statistically analyzed and clustered. An in-depth analysis of the obtained entire mass spectra showed differences between AFB1-producing and non-producing strains of A. flavus. Statistical and cluster analysis divided AFB1-producing and non-producing strains of A. flavus into two monasteries. The results indicate that it is possible to distinguish between AFB1 producers and non-producers by comparing the entire mass spectra using MALDI-TOF MS. Finally, we demonstrated that if there are established local AFB1-producing and non-producing strains of A. flavus, the entire mass spectrum database identification of aflatoxigenic A. flavus strains can be even faster and cheaper, without the need to identify the toxin itself

Antifungal and Antitoxigenic Effects of Selected Essential Oils in Vapors on Green Coffee Beans with Impact on Consumer Acceptability

The main objective of this study is to evaluate the effect of selected essential oils thyme chemotype linalool (Thymus zygis L.), thyme chemotype tymol (Thymus vulgaris L.), eucalyptus (Eucalyptus globulus Labill.), lavender (Lavandula angustifolia Mill.), mint (Mentha piperita L.), almond (Prunbus dulcis Mill.), cinnamon bark (Cinnamomum zeylanicum Nees), litsea (Litsea cubeba Lour. Pers), lemongrass (Cympogon citrati L. Stapf), and ginger (Zingiber officinalis Rosc.) in the vapor phase on growth, sporulation, and mycotoxins production of two Aspergillus strains (Aspergillus parasiticus CGC34 and Aspergillus ochraceus CGC87), important postharvest pathogens of green and roasted coffee beans. Moreover, the effect of the essential oils (EOs) on the sensory profile of the coffee samples treated with EOs was evaluated. The major components of tested EOs were determined by gas chromatography and mass spectrometry (GC–MS) and gas chromatography with flame ionization detector (GC-FID). The results showed that almond, cinnamon bark, lemongrass, and litsea EOs are able to significantly inhibit the growth, sporulation, and mycotoxins production by toxigenic fungi. Sensory evaluation of coffee beans treated with EOs before and after roasting showed that some EOs (except lemongrass and litsea) do not adversely affect the taste and aroma of coffee beverages. Thus, application of the vapors of almond and cinnamon EOs appears to be an effective way that could serve to protect coffee during its transport and storage from toxigenic fungi