Hexosomal Dispersion: A Nano-Based Approach to Boost the Antifungal Potential of Citrus Essential Oils against Plant Fungal Pathogens

The demand for natural fungicides to replace synthetic ones has surged since toxic residues persist in soils, causing environmental contamination and posing a serious threat to worldwide public health. In the context of crop protection and enhancing the efficiency and safety of fungicides, nanotechnology is an eco-friendly strategy in managing fungal pathogens. In the present study, essential oils were isolated from the peels of four citrus fruits (Citrus lemon, Citrus aurantifolia, Citrus maxima, and Citrus sinensis) and were investigated using gas chromatography-mass spectrometric analysis. Monoterpene hydrocarbon was the most predominant group and limonene was the most abundant in the four oils. The antifungal potential of the oils was investigated, and the most active oil (Citrus lemon) was loaded into hexosomal dispersion, and its antifungal potential was retested against the same fungi. The structurally unique nano-based formulation showed great potency for fungal control. To the best of our knowledge, it is the first time the oil of Citrus lemon in nano-hexosomes has been formulated and its fungicidal activity examined. The data collected suggest that citrus essential oils (CEOs), especially when nano-formulated, could be successfully used in integrated fungus management programs.

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Citrus Essential Oils: A Suite of Insecticidal Compounds

10.5772/intechopen.95887 ◽

2021 ◽

Author(s):

Bulbuli Khanikor ◽

Kamal Adhikari ◽

Bikash Rabha

Keyword(s):

Essential Oils ◽

Insect Pests ◽

Major Constituent ◽

Citrus Limon ◽

Fumigant Toxicity ◽

Citrus Paradisi ◽

North Eastern ◽

Citrus Maxima ◽

Citrus Essential Oils ◽

North Eastern Part

Citrus essential oils (CEOs) and their constituent compounds are being reported to have multifarious activities. In this chapter an attempt is made to discuss the insecticidal activities, as well as CEO profile of different vegetative part of Citrus species and biocidal potentiality of their constituent compounds against diverse insect pests. It is observed that in most of the CEO constituent profile, limonene is the major constituent compound. Other important constituents present in different percentages in different CEOs are β-citronellal, linalool, pinene, β- caryophyllene, β-myrcene, terpinene, citral etc. These plant EO constituents are reported to have insecticidal effects against diverse insect species. Taking the four peel EOs of Citrus limon, Citrus paradisi, Citrus medica, Citrus maxima commonly grown in North Eastern part of India, study on their insecticidal effects against Dolichoderus affinis (Hymenoptera: Formicidae) was made and result is presented showing higher fumigant toxicity of C. medica and C. limon oil against the ant sp. With the increasing awareness for using safe insecticidal products among consumers, the citrus EOs with their attracting terpene compounds having good insecticidal potency bear all attributes to be used as commercial green pesticides in coming days both in indoor and outdoor management of insect pests.

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Activity of Free and Liposome-Encapsulated Essential Oil from Lavandula angustifolia against Persister-Derived Biofilm of Candida auris

Antibiotics ◽

10.3390/antibiotics11010026 ◽

2021 ◽

Vol 11 (1) ◽

pp. 26

Author(s):

Elisabetta de Alteriis ◽

Angela Maione ◽

Annarita Falanga ◽

Rosa Bellavita ◽

Stefania Galdiero ◽

...

Keyword(s):

Essential Oil ◽

Essential Oils ◽

Fungal Pathogens ◽

Fungal Infections ◽

Intrinsic Resistance ◽

Candida Auris ◽

Lavandula Angustifolia ◽

Model Following ◽

Global Threat ◽

First Time

The high virulence of Candida auris, a pathogen fungus considered as a global threat for public health, is due to its peculiar traits such as its intrinsic resistance to conventional antifungals. Its biofilm lifestyle certainly promotes the prolonged survival of C. auris after disinfection or antifungal treatments. In this work, for the first time, we detected persister cells in a biofilm of C. auris in a microwell plate model, following caspofungin treatment. Furthermore, we showed how persisters can progressively develop a new biofilm in situ, mimicking the re-colonization of a surface which may be responsible for recalcitrant infections. Plant-derived compounds, such as essential oils, may represent a valid alternative to combat fungal infections. Here, Lavandula angustifolia essential oil, as free or encapsulated in liposomes, was used to eradicate primary and persister-derived biofilms of C. auris, confirming the great potential of alternative compounds against emergent fungal pathogens. As in other Candida species, the action of essential oils against C. auris involves ROS production and affects the expression of some biofilm-related genes.

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Evaluation of Seven Essential Oils as Seed Treatments against Seedborne Fungal Pathogens of Cucurbita maxima

Molecules ◽

10.3390/molecules26082354 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2354

Author(s):

Marwa Moumni ◽

Mohamed Bechir Allagui ◽

Kaies Mezrioui ◽

Hajer Ben Amara ◽

Gianfranco Romanazzi

Keyword(s):

Essential Oil ◽

Essential Oils ◽

Fungal Pathogens ◽

Seedling Emergence ◽

Cucurbita Maxima ◽

Melaleuca Alternifolia ◽

Seedborne Pathogens ◽

Origanum Majorana ◽

Potential Use

Essential oils are gaining interest as environmentally friendly alternatives to synthetic fungicides for management of seedborne pathogens. Here, seven essential oils were initially tested in vivo for disinfection of squash seeds (Cucurbita maxima) naturally contaminated by Stagonosporopsis cucurbitacearum, Alternaria alternata, Fusarium fujikuro, Fusarium solani, Paramyrothecium roridum, Albifimbria verrucaria, Curvularia spicifera, and Rhizopus stolonifer. The seeds were treated with essential oils from Cymbopogon citratus, Lavandula dentata, Lavandula hybrida, Melaleuca alternifolia, Laurus nobilis, and Origanum majorana (#1 and #2). Incidence of S. cucurbitacearum was reduced, representing a range between 67.0% in L. nobilis to 84.4% in O. majorana #2. Treatments at 0.5 mg/mL essential oils did not affect seed germination, although radicles were shorter than controls, except with C. citratus and O. majorana #1 essential oils. Four days after seeding, seedling emergence was 20%, 30%, and 10% for control seeds and seeds treated with C. citratus essential oil (0.5 mg/mL) and fungicides (25 g/L difenoconazole plus 25 g/L fludioxonil). S. cucurbitacearum incidence was reduced by ~40% for plantlets from seeds treated with C. citratus essential oil. These data show the effectiveness of this essential oil to control the transmission of S. cucurbitacearum from seeds to plantlets, and thus define their potential use for seed decontamination in integrated pest management and organic agriculture.

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The Use of Essential Oils from Thyme, Sage and Peppermint against Colletotrichum acutatum

Plants ◽

10.3390/plants10010114 ◽

2021 ◽

Vol 10 (1) ◽

pp. 114

Author(s):

Armina Morkeliūnė ◽

Neringa Rasiukevičiūtė ◽

Lina Šernaitė ◽

Alma Valiuškaitė

Keyword(s):

Essential Oils ◽

Fungal Pathogens ◽

Control Plant ◽

Antimicrobial Activities ◽

Plant Diseases ◽

Colletotrichum Acutatum ◽

Low Toxicity ◽

Colletotrichum Spp ◽

Biological Protection

The Colletotrichum spp. is a significant strawberry pathogen causing yield losses of up to 50%. The most common method to control plant diseases is through the use of chemical fungicides. The findings of plants antimicrobial activities, low toxicity, and biodegradability of essential oils (EO), make them suitable for biological protection against fungal pathogens. The aim is to evaluate the inhibition of Colletotrichum acutatum by thyme, sage, and peppermint EO in vitro on detached strawberry leaves and determine EO chemical composition. Our results revealed that the dominant compound of thyme was thymol 41.35%, peppermint: menthone 44.56%, sage: α,β-thujone 34.45%, and camphor: 20.46%. Thyme EO inhibited C. acutatum completely above 200 μL L−1 concentration in vitro. Peppermint and sage EO reduced mycelial growth of C. acutatum. In addition, in vitro, results are promising for biological control. The detached strawberry leaves experiments showed that disease reduction 4 days after inoculation was 15.8% at 1000 μL L−1 of peppermint EO and 5.3% at 800 μL L−1 of thyme compared with control. Our findings could potentially help to manage C. acutatum; however, the detached strawberry leaves assay showed that EO efficacy was relatively low on tested concentrations and should be increased.

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The Volatile Phytochemistry of Seven Native American Aromatic Medicinal Plants

Plants ◽

10.3390/plants10061061 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1061

Author(s):

Sims K. Lawson ◽

Prabodh Satyal ◽

William N. Setzer

Keyword(s):

Native American ◽

Medicinal Plants ◽

Essential Oil ◽

Essential Oils ◽

Palmitic Acid ◽

Methyl Salicylate ◽

Chromatographic Techniques ◽

Germacrene D ◽

First Time ◽

Gaultheria Procumbens

As part of our evaluation of essential oils derived from Native American medicinal plants, we have obtained the essential oils of Agastache foeniculum (Pursch) Kuntze (Lamiaceae), Gaultheria procumbens L. (Ericaceae), Heliopsis helianthoides (L.) Sweet (Asteraceae), Liatris spicata (L.) Willd. (Asteraceae), Pycnanthemum incanum (L.) Michx. (Lamiaceae), Smallanthus uvedalia (L.) Mack. ex Mack. (Asteraceae), and Verbena hastata L. (Verbenaceae) by hydrodistillation. The essential oils were analyzed by gas chromatographic techniques. The essential oil of A. foeniculum was dominated by estragole (88–93%), while methyl salicylate (91%) dominated the G. procumbens essential oil. Germacrene D was the major component in H. helianthoides (42%) and L. spicata (24%). 1,8-Cineole (31%) and α-terpineol (17%) were the main compounds in P. incanum essential oil. The essential oil of S. uvedalia showed α-pinene (24%), perillene (15%), and β-caryophyllene (17%) as major components. Verbena hastata essential oil was rich in 1-octen-3-ol (up to 29%) and palmitic acid (up to 22%). Four of these essential oils, H. helianthoides, L. spicata, P. incanum, and V. hastata, are reported for the first time. Additionally, the enantiomeric distributions of several terpenoid components have been determined.

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Citrus essential oils and main terpenes: chemical composition and good litholytic activity on gallstones

Vegetos- An International Journal of Plant Research ◽

10.1007/s42535-021-00251-9 ◽

2021 ◽

Author(s):

Asma Arrout ◽

Yassine El Ghallab ◽

Mohammed Rachid Lefriyekh ◽

Amal Ait Haj Said

Keyword(s):

Chemical Composition ◽

Essential Oils ◽

Citrus Essential Oils

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Bioinsecticides based on plant essential oils: a short overview

Zeitschrift für Naturforschung C ◽

10.1515/znc-2020-0038 ◽

2020 ◽

Vol 75 (7-8) ◽

pp. 179-182

Author(s):

Murray B. Isman

Keyword(s):

Essential Oils ◽

Crop Protection ◽

Large Body ◽

Regulatory Agencies ◽

The European Union ◽

Plant Essential Oils ◽

The Past ◽

Wide Range ◽

The Usa ◽

Regulatory Challenges

AbstractInterest in the discovery and development of plant essential oils for use as bioinsecticides has grown enormously in the past 20 years. However, successful commercialization and utilization of crop protection products based on essential oils has thus far lagged far behind their promise based on this large body of research, most notably because with the exceptions of the USA and Australia, such products receive no special status from regulatory agencies that approve new pesticides for use. Essential oil-based insecticides have now been used in the USA for well over a decade, and more recently have seen use in the European Union (EU), Korea, and about a dozen other countries, with demonstrated efficacy against a wide range of pests and in numerous crop systems. For the most part these products are based on commodity essential oils developed as flavor and fragrance agents for the food and cosmetic industries, as there are formidable logistic, economic, and regulatory challenges to the use of many other essential oils that otherwise possess potentially useful bioactivity against pests. In spite of these limitations, the overall prospects for biopesticides, including those based on essential oils, are encouraging as the demand for sustainably-produced and/or organic food continues to increase worldwide.

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Determination of Essential Oil Bioactive Components and Rosmarinic Acid of Salvia officinalis Cultivated under Different Intra-row Spacing

Notulae Scientia Biologicae ◽

10.15835/nsb529046 ◽

2013 ◽

Vol 5 (2) ◽

pp. 198-203 ◽

Cited By ~ 3

Author(s):

Mohammad ABU DARWISH ◽

Ezz Al-Dein AL-RAMAMNEH ◽

Ivan SALAMON ◽

Ziad ABU-DIEYEH ◽

Mohamed AL NAWAISEH ◽

...

Keyword(s):

Essential Oil ◽

Essential Oils ◽

Rosmarinic Acid ◽

Plant Density ◽

Salvia Officinalis ◽

Raw Material ◽

Row Spacing ◽

Human Disorders ◽

Tea Production ◽

First Time

Salvia officinalis, known also as sage, is a medicinal plant belonging to the Lamiaceae family that spreads all over the word in several countries. The demand for the raw material and extracts of this plant is increasing due to its numerous applications in pharmacy, food and herbal tea production. The present study investigated for the first time the effect of 15, 30 and 45 cm intra-row spacing (plant density) on the main constituents of sage essential oils and rosmarinic acid content. The highest content of essential oils (2.7%) and rosmarinic acid (2.0%) were obtained in plants grown using 15 cm planting space. Likewise, close spacing resulted also in a substantial content of 1,8-cineole (47-50%, GC/FID; 55-60%, GC/MS). This work indicated that 1,8-cineole chemotype was a dominant character of cultivated S. officinalis in south of Jordan. In general, the percent of α-thujone in essential oil was not affected by intra-row spacing. However, the percent of β-thujone decreased from (2-3%, GC/MS) in plants grown using 15 cm intra-row spacing to (1-2%, GC/MS) in plants grown using 30 and 45 cm intra-row spacing. The highest content of α-and β-pinene was recorded in plants grown using 45 cm planting space (8-10%, GC/FID; 5-6% GC/MS). Based on GC/MS, camphor compound was enriched (9-10%) in sage plants grown under 15 cm spacing and greater than in plants grown under 30 (6-7%) or 45 cm (5-6%) spacing. The results make the potential use of sage extracts in the treatment of some human disorders or illness an area of further research.

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