Volume 8, Issue 4 (12-2022)
Abstract
Backgrounds: Nowadays, excessive use of fungal drugs has led to the development of drug-resistant fungi, making it necessary to find natural and herbal antifungal agents. This in-vitro study aimed to evaluate the interactions of Satureja hortensis and Carum carvi essential oils together and each essential oil with fluconazole against Candida albicans ATCC-10231.
Materials & Methods: In this study, antifungal properties of different concentrations of S. hortensis (0.0244-1.56 μL/mL) and C. carvi (0.39-25 μL/mL) were investigated by broth-microdilution method based on CLSI M27-A3 and M27-S4 standard documents. The interactions of essential oils together and each essential oil with fluconazole were evaluated by checkerboard assay. Then using the ΣFIC index, the interaction results were interpreted.
Findings: S. hortensis essential oil showed higher antifungal activity than C. carvi essential oil. (MIC/MFC: S. hortensis: 1.56/3.12 μL/mL and C. carvi: 12.5/25 μL/mL). The interaction between S. hortensis essential oil and fluconazole was on the synergic and additive borderline (FICI=0.508), the interaction between C. carvi essential oil and fluconazole was additive (FICI=0.62), and C. carvi and S. hortensis essential oils showed no interaction together (FICI=2.015).
Conclusion: The essential oils of S. hortensis and C. carvi separately exhibited powerful antifungal activities. The use of S. hortensis essential oil at a very low concentration along with fluconazole caused an interaction very close to synergy and increased fluconazole antifungal activity. Therefore, S. hortensis is a potential candidate for combined use with fluconazole to treat C. albicans related diseases.
Aisan Afkhamifar, Cobra Moslemkhani, Nader Hasanzadeh, Javad Razmi, Leila Sadeghi,
Volume 12, Issue 4 (12-2023)
Abstract
Wheat seeds harbor different microbial populations, which can be associated with each other in neutral, positive, or negative interactions. The present study investigated the interaction of fluorescent Pseudomonas and Xanthomonas translucens (Xt) as an important wheat seed-borne pathogen. In addition to P. fluorescens (A7) and P. chloroaphis (A4), which were previously isolated from the rhizosphere of potato as potent biocontrol agents, six more non-pathogenic Pseudomonas strains that were isolated from wheat seeds, were studied. According to the general biochemical tests and partial 16S rRNA sequences alignment, the isolated strains were closely related to the species of P. gessardii, P. orientalis, P. poae, P. koreensis, and P. cedrina. The Pseudomonas strains exhibit different antagonistic activities, such as phosphate solubilization, cellulase, protease, and lipase production. Also, they have an apparent inhibition effect under in vivo conditions against X. translucens. Seed treatment by these strains led to suppressing bacterial leaf streak disease incidence in an early growth stage. However, disease progress enhanced with the seedling growth, resulting in the treated plants' complete death. Only in treated seeds by P. fluorescens (A7), P. chloroaphis(A4), and P. orientalis (Ais119) decrease of AUDPC up to 83%, 74%, and 63% was achieved, respectively, compared with the untreated controls. Our results showed that some fluorescent Pseudomonas strains could cause delay at the beginning of the disease appearance due to competition or producing antimicrobial metabolites during that time. In contrast, some may be considered a threat, enhancing disease development through synergistic effects.
Volume 13, Issue 1 (4-2013)
Abstract
Central nervous system (CNS) uses an abundant set of joints and muscles to ensure both flexible and stable movements while interacting the environment. How the CNS faces the complexity of control problem and solves the question of physiological and mechanical abundances is not still clear. Modular control is one of the most prevalent hypotheses in answer to these questions. According to this point of view, CNS combines a few building blocks, here this will be muscle activities, named as muscle synergies, to present a vast repertoires of movements. In this study the algorithm of sample-based nonnegative matrix tri-factorization (NM3F) is used to extract spatial and temporal muscle synergy modules from muscle EMG data for three different types of point to point reaching (simple straight, reversal and via-point) movement in the frontal and sagittal planes. After extracting different features of the muscle synergies, physiological interpretation of these decomposed parts has been discussed. The first temporal module coded the direction and type of movement, while the spatial modules describe some via postures. Also the extracted modules are not similar for subjects. The recruitment of the spatial and temporal modules are correlated due to the movement direction.