Chemical Composition and Antifungal Activity of Zanthoxylum armatum Fruit Essential Oil against Phytophthora capsici

Abstract

Pathogenic plant oomycetes cause devastating damage to fruits and vegetables worldwide. Plant essential oils (EOs) are known to be promising candidates for the development of fungicides. In this study, we isolated twelve EOs from Tetradium ruticarpum, Tetradium daniellii, Tetradium fraxinifolium, Zanthoxylum armatum, Ruta graveolens, and Citrus medica leaves and fruits. We then investigated their chemical composition and antifungal activity against phytopathogenic oomycetes. Our results demonstrated that Z. armatum fruit essential oil (ZFO) in particular substantially inhibited the mycelial growth of Phytophthora capsici. Similarly, ZFO also strongly suppressed spore production and germination of P. capsici, and the application of ZFO significantly reduced disease symptoms caused by P. capsici in pepper. Furthermore, results from microscopic and biochemical studies indicated that ZFO damaged the ultrastructure and destroyed the membrane integrity of P. capsici, leading to the leakage of the cellular contents and ultimately causing cell death. It was concluded that ZFO could enhance the activities of defense-related enzymes in pepper fruits, which may also be responsible for the inhibition of phytophthora disease. Moreover, linalool and D-limonene were proven to be the primary effective components of ZFO. Our results collectively indicate that ZFO could be a potential candidate for the management of disease caused by P. capsici.

Antifungal activity of the botanical compound rhein against Phytophthora capsici and the underlying mechanisms

“…Several plant extracts exert antifungal functions by acting directly or indirectly on the cell membrane and cell wall of fungi, destroying the permeability of the cell membrane, damaging the integrity of the cell wall, and leaking important cell components. 27,29 Given the satisfactory antifungal activity of rhein against P. capsici, the antifungal mechanism of rhein was further investigated in this study. We found that rhein could severely affect the permeability and damage the integrity of the cell membrane, resulting in reduced membrane transport.…”

“…Similar results showing damage to the cell wall integrity have been reported in Geotrichum citri-aurantii treated with peppermint essential oil or P. capsici treated with euphorbia factor L 3 . 28,29 Moreover, the OM and TEM results indicated that the morphology and ultrastructure of mycelia were altered after treating P. capsici with rhein. These morphological changes could be attributed to the increased membrane permeability, resulting in the leakage of small molecules and increased membrane lipid peroxidation, thus accelerating cell death.…”

“…Calcofluor white (CFW) staining was conducted to clarify the effect of rhein on cell wall integrity. 29 Mycelial plugs of P. capsici were cut and cultured in V8-juice medium in a shaker (175 rpm) at 25 °C for 48 h. Then, rhein (0, 5, and 10 μg mL −1 ) was added to the medium. After incubating for 24 h, the mycelia of P. capsici were washed with PBS solution and stained with 1% CFW.…”

How to Naturally Support the Immune System in Inflammation—Essential Oils as Immune Boosters

“… suppresses antigen-induced lymphocyte activation The composition of essential oil from fruit of the plant grown in Kagoshima, Japan/Yamaguchi, Japan: α-Pinene 1.78/1.18 β-Myrcene 2.97/3.54 Limonene 60.30/71.34 β-Phellandrene 8.22/7.27 α-Terpinene 5.12/5.51 p-Cymene 6.08/3.56 γ-Elemene 1.93/- α-terpineol -/1.90 (E,E)-α-farnesene -/1.00 [ 127 , 154 , 155 ] 11. Euodia ruticarpa ( E. ruticarpia ) (Rutaceae) It exhibits anticancer propeties by: increasing the level of IL-1β, TNF-α, IL-6 and IL-10 secreted by macrophages affecting regulation of Th1 (IL-2) and Th2 (IL-10) cytokines production by splenocytes activating NK cells and B cells The composition of essential oil from leaf /fruit: β-myrcene 31.03/38.14 β-phellandrene 18.38/25.89 trans-β-ocimene 3.35/- β-ocimene 3.21/17.82 (E)-4,8-dimethyl-1,3,7-nonatriene 6.17/- caryophyllene 2.21/- E-nerolidol 21.79/- γ-eudesmol 1.09/- β-eudesmol 1.52/- α-eudesmol 2.1/- α-pinene -/1.63 trans-β-ocimene -/12.29 [ 32 , 130 , 131 , 132 , 133 , 134 , 135 , 156 ] 12. Eucalyptus plant (Myrtaceae) Its topical application inhibits edema and enhances vascular permeability in IgE-mediated allergic dermatitis it may stimulate the immune function of the respiratory tract, improves phagocytic activity of macrophages and it can be used as an adjuvant in some infections and inflammatory diseases.…”

Harnessing Plant’s Arsenal: Essential Oils as Promising Tools for Sustainable Management of Potato Late Blight Disease Caused by Phytophthora infestans—A Comprehensive Review

“…Conjointly, EOs are regularly more effective for preventive applications (i.e., applied before inoculation) than for curative uses (i.e., applied after inoculation) [121][122][123]. These two modes of application clearly target two opposing but complementary stages of the disease.…”