Effect of seasonality on chemical profile and antifungal activity of essential oil isolated from leaves Psidium salutare (Kunth) O. Berg

Abstract

Medicinal plants play a crucial role in the search for components that are capable of neutralizing the multiple mechanisms of fungal resistance. Psidium salutare (Kunth) O. Berg is a plant native to Brazil used as both food and traditional medicine to treat diseases and symptoms such as stomach ache and diarrhea, whose symptoms could be related to fungal infections from the genus Candida. The objective of this study was to investigate the influence of seasonal variability on the chemical composition of the Psidium salutare essential oil, its antifungal potential and its effect on the Candida albicans morphogenesis. The essential oils were collected in three different seasonal collection periods and isolated by the hydrodistillation process in a modified Clevenger apparatus with identification of the chemical composition determined by gas chromatography coupled to mass spectrometry (GC/MS). The antifungal assays were performed against Candida strains through the broth microdilution method to determine the minimum fungicidal concentration (MFC). Fungal growth was assessed by optical density reading and the Candida albicans dimorphic effect was evaluated by optical microscopy in microculture chambers. The chemical profile of the essential oils identified 40 substances in the different collection periods with γ-terpinene being the predominant constituent. The antifungal activity revealed an action against the C. albicans, C. krusei and C. tropicalis strains with an IC50 ranging from 345.5 to 2,754.2 µg/mL and a MFC higher than 1,024 µg/mL. When combined with essential oils at sub-inhibitory concentrations (MIC/16), fluconazole had its potentiated effect, i.e. a synergistic effect was observed in the combination of fluconazole with P.salutare oil against all Candida strains; however, for C. albicans, its effect was reinforced by the natural product in all the collection periods. The results show that the Psidium salutare oil affected the dimorphic transition capacity, significantly reducing the formation of hyphae and pseudohyphae in increasing concentrations. The results show that P. salutare oil exhibits a significant antifungal activity against three Candida species and that it can act in synergy with fluconazole. These results support the notion that this plant may have a potential use in pharmaceutical and preservative products.

Evaluation of larvicidal potential against larvae of Aedes aegypti (Linnaeus, 1762) and of the antimicrobial activity of essential oil obtained from the leaves of Origanum majorana L.

“…Piperitone is derived from the metabolic pathway for the formation of piperitenone oxide, in which cis-pulegone is also, derived [ 43 ]. Macêdo et al [ 44 ] observe that the variations of the active components of the plant are important parameters to correlate the activities, such as antibacterial and insecticide.…”

Characterization of Composition and Antifungal Properties of Leaf Secondary Metabolites from Thirteen Cultivars of Chrysanthemum morifolium Ramat

“…Many apolar secondary metabolites detected from C. morifolium , especially terpenoids, are known to have antimicrobial activities [21,22,23,24,25]. To evaluate the antimicrobial properties of the apolar secondary metabolites from C. morifolium leaves, we tested three species of pathogenic fungi, Fusarium oxysporum , Magnaporthe oryzae , and Verticillium dahliae .…”

“…Among these four cultivars, the extract of ‘Bai xiang li’ (Cm 13) exhibited an inhibitive effect on the growth of all three species of fungi, while ‘Wan gong ju’ (Cm 9), ‘Su ju 9’ (Cm 11), and ‘Xiao huang ju’ (Cm 10) showed the inhibitive effect only to M. oryzae. Many terpenoid compounds identified in C. morifolium leaves have been reported to have an antifungal effect on various species of fungi [21,22,23,24,25]. By comparing the PCA/HCA results based on terpenoid contents and antifungal activities, the antifungal effects of several cultivars (including ‘Da yang ju’ (Cm 5), ‘Huang xiang li’ (Cm 6), ‘Huang ju’ (Cm 8), ‘She yang hong xin ju’ (Cm 12)) could be associated with several terpenoids, including zingiberene, β-sesquiphellandrene, α-curcumene, ( E )-β-farnesene, and α-farnesene.…”

Larvicidal evaluation of the Origanum majorana L. Essential Oil against the larvae of the Aedes aegypti mosquito

“…Macêdo et al [26] observe that the variations of the active components of the plant are important parameters to correlate the activities, such as antibacterial and insecticide.…”

“…In addition, a number of biotic factors such as plant/ microorganism Stoppacher et al [27], plants/ insects Kessler and Baldwin [28] plant interactions, age and stage of development. As well as abiotic factors such as luminosity Takshak and Agrawal [29], temperature, precipitation, nutrition, time and harvest time Bitu et al [30], they may present correlations with each other, acting together, and they may exert a joint influence on chemical variability and yield of essential oil [26]. and Dias et al [33], classified with the values of the minimum lethal concentration that eliminates 50% of the population (LC50) as a criterion for the activity.…”