Antifungal activity of selected volatile essential oils against Penicillium sp

Mesoporous silica nanoparticles: A versatile platform for encapsulation and delivery of essential oils for food applications

Essential oils (EOs) are biologically active and volatile substances that have found widespread applications in the food, cosmetics, and pharmaceutical industries. However, there are some challenges to their commercial utilization due to their high volatility, susceptibility to degradation, and hydrophobicity. In their free form, EOs can quickly evaporate, as well as undergo degradation reactions like oxidation, isomerization, dehydrogenation, or polymerization when exposed to light, heat, or air. Encapsulating EOs within mesoporous silica nanoparticles (MSNPs) could overcome these limitations and thereby broaden their usage. MSNPs may endow protection and slow-release properties to EOs, thereby extending their stability, enhancing their efficacy, and improving their dispersion in aqueous environments. This review explores and compares the design and development of different MSNP-based nanoplatforms to encapsulate, protect, and release EOs. Initially, a brief overview of the various types of available MSNPs, their properties, and their synthesis methods is given to better understand their roles as carriers for EOs. Several encapsulation technologies are then examined, including solvent-based and solvent-free methods. The suitability of each technology for EO encapsulation, as well as its impact on their stability and release, is discussed in detail. Opportunities and challenges for using EO-loaded MSNPs as preservatives, flavor enhancers, and antimicrobial agents in the food industry are then highlighted. Overall, this review aims to bridge a knowledge gap by providing a thorough understanding of EO encapsulation within MSNPs, which should facilitate the application of this technology in the food industry.

Carvacrol Encapsulation in Chitosan-Carboxymethylcellulose-Alginate Nanocarriers for Postharvest Tomato Protection

Advancements in polymer science and nanotechnology hold significant potential for addressing the increasing demands of food security, by enhancing the shelf life, barrier properties, and nutritional quality of harvested fruits and vegetables. In this context, biopolymer-based delivery systems present themselves as a promising strategy for encapsulating bioactive compounds, improving their absorption, stability, and functionality. This study provides an exploration of the synthesis, characterization, and postharvest protection applications of nanocarriers formed through the complexation of chitosan oligomers, carboxymethylcellulose, and alginate in a 2:2:1 molar ratio. This complexation process was facilitated by methacrylic anhydride and sodium tripolyphosphate as cross-linking agents. Characterization techniques employed include transmission electron microscopy, energy-dispersive X-ray spectroscopy, infrared spectroscopy, thermal analysis, and X-ray powder diffraction. The resulting hollow nanospheres, characterized by a monodisperse distribution and a mean diameter of 114 nm, exhibited efficient encapsulation of carvacrol, with a loading capacity of approximately 20%. Their suitability for phytopathogen control was assessed in vitro against three phytopathogens-Botrytis cinerea, Penicillium expansum, and Colletotrichum coccodes-revealing minimum inhibitory concentrations ranging from 23.3 to 31.3 μg·mL-1. This indicates a higher activity compared to non-encapsulated conventional fungicides. In ex situ tests for tomato (cv. 'Daniela') protection, higher doses (50-100 μg·mL-1, depending on the pathogen) were necessary to achieve high protection. Nevertheless, these doses remained practical for real-world applicability. The advantages of safety, coupled with the potential for a multi-target mode of action, further enhance the appeal of these nanocarriers.

The efficient activity of plant essential oils for inhibiting Botrytis cinerea and Penicillium expansum: Mechanistic insights into antifungal activity

Botrytis cinerea and Penicillium expansum produce deterioration in fruit quality, causing losses to the food industry. Thus, plant essential oils (EOs) have been proposed as a sustainable alternative for minimizing the application of synthetic fungicides due to their broad-spectrum antifungal properties. This study investigated the efficacy of five EOs in suppressing the growth of B. cinerea and P. expansum and their potential antifungal mechanisms. EOs of Mentha × piperita L., Origanum vulgare L., Thymus vulgaris L., Eucalyptus globules Labill., and Lavandula angustifolia Mill., were screened for both fungi. The results showed that the EO of T. vulgaris and O. vulgare were the most efficient in inhibiting the growth of B. cinerea and P. expansum. The concentration increase of all EO tested increased fungi growth inhibition. Exposure of fungi to EOs of T. vulgaris and O. vulgare increased the pH and the release of constituents absorbing 260 nm and soluble proteins, reflecting membrane permeability alterations. Fluorescence microscopic examination revealed that tested EOs produce structural alteration in cell wall component deposition, decreasing the hypha width. Moreover, propidium iodide and Calcein-AM stains evidenced the loss of membrane integrity and reduced cell viability of fungi treated with EOs. Fungi treated with EOs decreased the mitochondria activity and the respiratory process. Therefore, these EOs are effective antifungal agents against B. cinerea and P. expansum, which is attributed to changes in the cell wall structure, the breakdown of the cell membrane, and the alteration of the mitochondrial activity.

Simultaneous Hydrodistillation of Cedrus atlantica Manetti and Salvia rosmarinus Spenn: Optimization of Anti-Wood-Decay Fungal Activity Using Mixture Design Methodology

Chemical fungicides are often harmful to people and the environment because of their toxicity. The wood protection industry places a high priority on replacing them with natural products. Therefore, this investigation focused on developing a formulation of a binary combination of Salvia rosmarinus Spenn and Cedrus atlantica Manetti obtained by Simultaneous hydrodistillation to protect the wood from decay using a mixture design methodology. The chemical composition of essential oil was identified by gas chromatography coupled with mass spectrometry (GC/MS), and their anti-wood-decay fungal activity was assessed using the macrodilution method against four fungi responsible for wood decay: Coniophora puteana, Coriolus versicolor, Gloeophyllum trabeum, and Poria placenta. The results of GC/MS identified myrtenal as a new component appearing in all binary combinations. The optimum anti-wood-decay fungal activity was observed in a combination of 60% S. rosmarinus and 40% C. atlantica essential oils, providing an effective concentration for 50% of maximal effect (EC50) value of 9.91 ± 1.91 and 9.28 ± 1.55 μg/mL for C. puteana and C. versicolor, respectively. The highest anti-wood-decay fungal activity for G. trabeum and P. placenta was found in the combination of 55% of S. rosmarinus and 45% of C. atlantica essential oils, with EC50 values of 11.48 ± 3.73 and 22.619 ± 3.79 μg/mL, respectively. Combined simultaneous hydrodistillation improved the antifungal effect of these essential oils. These results could be used to improve antifungal activity and protect wood against wood-decay fungi.

Lignin Nanoparticles with Entrapped Thymus spp. Essential Oils for the Control of Wood-Rot Fungi

After decades of utilization of fossil-based and environmentally hazardous compounds for wood preservation against fungal attack, there is a strong need to substitute those compounds with bio-based bioactive solutions, such as essential oils. In this work, lignin nanoparticles containing four essential oils from thyme species (Thymus capitatus, Coridothymus capitatus, T. vulgaris, and T. vulgaris Demeter) were applied as biocides in in vitro experiments to test their anti-fungal effect against two white-rot fungi (Trametes versicolor and Pleurotus ostreatus) and two brown-rot fungi (Poria monticola and Gloeophyllum trabeum). Entrapment of essential oils provided a delayed release over a time frame of 7 days from the lignin carrier matrix and resulted in lower minimum inhibitory concentrations of the essential oils against the brown-rot fungi (0.30-0.60 mg/mL), while for the white-rot fungi, identical concentrations were determined compared with free essential oils (0.05-0.30 mg/mL). Fourier Transform infrared (FTIR) spectroscopy was used to assess the fungal cell wall changes in the presence of essential oils in the growth medium. The results regarding brown-rot fungi present a promising approach for a more effective and sustainable utilization of essential oils against this class of wood-rot fungi. In the case of white-rot fungi, lignin nanoparticles, as essential oils delivery vehicles, still need optimization in their efficacy.

Hermetia illucens frass improves the physiological state of basil (Ocimum basilicum L.) and its nutritional value under drought

To counterbalance the growing human population and its increasing demands from the ecosystem, and the impacts on it, new strategies are needed. Use of organic fertilizers boosted the agricultural production, but further increased the ecological burden posed by this indispensable activity. One possible solution to this conundrum is the development and application of more environmentally neutral biofertilizers. The aim of this study was to compare the effectiveness of two doses of Hermetia illucens frass (HI frass) with the commercial cattle manure in the cultivation of basil under drought. Soil without the addition of any organic fertilizer was used as a baseline control substrate for basil cultivation. Plants were grown with cattle manure (10 g/L of the pot volume) or HI frass at two doses (10 and 12.5 g/L). The health and physiological condition of plants were assessed based on the photosynthetic activity and the efficiency of photosystem II (chlorophyll fluorescence). Gas exchange between soil and the atmosphere were also assessed to verify the effect of fertilizer on soil condition. In addition, the mineral profile of basil and its antioxidant activity were assessed, along with the determination of the main polyphenolic compounds content. Biofertilizers improved the fresh mass yield and physiological condition of plants, both under optimal watering and drought, in comparison with the non-fertilized controls. Use of cattle manure in both water regimes resulted in a comparably lower yield and a stronger physiological response to drought. As a result, using HI frass is a superior strategy to boost output and reduce the effects of drought on basil production.

The Vapor Phase of Selected Essential Oils and Their Antifungal Activity In Vitro and In Situ against Penicillium commune, a Common Contaminant of Cheese

This study aimed to determine the in vitro and in situ antifungal activity of (14) selected essential oils (EOS), namely clove, thyme, red thyme, litsea, eucalyptus, niaouli, fennel, anise, cumin, basil, rosemary, sage, bergamot mint, and marjoram, by vapor contact against the growth of two strains of Penicillium commune (KMi-183 and KMi-402). Furthermore, to exclude the negative effect of EOs on the lactic acid bacteria (LABs) (Streptococcus spp.) on cheeses, their influence was monitored. Next, the sensory evaluation of cheese treated by EOs was evaluated. The results show that litsea and clove EOs were the most effective in the vapor phase against both tested strains. These EOs were characterized by the highest amount of α- (40.00%) and β-Citral (34.35%) in litsea and eugenol (85.23%) in clove. The antitoxicogenic activity of less effective (in growth inhibition) EOs on cyclopiazonic acid (CPA) production by the tested strains was also observed. The growth of Streptococcus spp. (ranging from 8.11 to 9.69 log CFU/g) was not affected by the EOs in treated cheese. Even though the evaluators recognized some EOs in sensory evaluation by the triangle test, they did not have a negative effect on the taste and smell of the treated cheeses and were evaluated as edible. The antifungal activity of EOs against several types of microscopic fungi and their effect on the sensory properties of treated foods needs to be further tested to achieve the most effective protection of foods from their direct contaminants.

Assessment of Chemical Composition and Anti-Penicillium Activity of Vapours of Essential Oils from Abies Alba and Two Melaleuca Species in Food Model Systems

The possibilities of the practical utilization of essential oils (EOs) from various plant species in the food industry have attracted the attention of the scientific community. Following our previous studies, the antifungal activities of three further commercial EOs, Melaleuca armillaris subsp. armillaris (rosalina; REO), Melaleuca quinquenervia (niaouli; NEO), and Abies alba (fir; FEO), were evaluated in the present research in respect to their chemical profiles, over four different concentrations, 62.5 μL/L, 125 μL/L, 250 μL/L, and 500 μL/L. The findings revealed that the major compounds of REO, NEO, and FEO were linalool (47.5%), 1,8-cineole (40.8%), and α-pinene (25.2%), respectively. In vitro antifungal determinations showed that the inhibition zones of a Penicillium spp. mycelial growth ranged from no inhibitory effectiveness (00.00 ± 00.00 mm) to 16.00 ± 1.00 mm, indicating a very strong antifungal activity which was detected against P. citrinum after the highest REO concentration exposure. Furthermore, the in situ antifungal efficacy of all EOs investigated was shown to be dose-dependent. In this sense, we have found that the highest concentration (500 µL/L) of REO, NEO, and FEO significantly reduced (p < 0.05) the growth of all Penicillium strains inoculated on the bread, carrot, and potato models. These results indicate that the investigated EOs may be promising innovative agents in order to extend the shelf life of different types of food products, such as bread, carrot and potato.

Assessment of Ocimum basilicum Essential Oil Anti-Insect Activity and Antimicrobial Protection in Fruit and Vegetable Quality

Basil (Ocimum basilicum) is a commonly used herb; it also contains essential oils and other valuable compounds. The basil oil obtained has a pleasant aroma, but also a broad spectrum of biological activity. This work reports on the chemical composition, antioxidant, antimicrobial and anti-insect activity in vitro and in situ of Ocimum basilicum essential oil (OBEO) obtained by steam distillation of fresh flowering plants. Gas chromatography-mass spectrometry, DPPH, agar and disc diffusion and vapor phase methods were used to analyze the OBEO properties. The analysis of the chemical composition of OBEO showed that its main components were methyl chavicol (88.6%), 1,8-cineole (4.2%) and α-trans-bergamotene (1.7%). A strong antioxidant effect was demonstrated at the level of 77.3%. The analysis of antimicrobial properties showed that OBEO exerts variable strength of inhibiting activity against various groups of microorganisms. The growth inhibition zones ranged from 9.67 to 15.33 mm in Gram-positive (G⁺) and Gram-negative (G^-) bacteria and from 5.33 to 7.33 mm in yeast. The lowest measured minimal inhibition concentration (MIC) was 3.21 µL/mL against Gram-negative Azotobacter chrococcum and Gram-positive Micrococcus luteus. The antimicrobial activity of in situ vapor phase of OBEO was also confirmed on apples, pears, potatoes and kohlrabi. The highest insecticidal activity against Pyrrhocorisapterus, observed at the concentration of 100%, caused the death of 80% of individuals. Due to its broad spectrum of activity, OBEO seems an ideal candidate for preserving fruit and vegetables.

Study on the Sustainability Potential of Thyme, Oregano, and Coriander Essential Oils Used as Vapours for Antifungal Protection of Wheat and Wheat Products

This study aims to highlight the antifungal, antimicotoxigenic potential and phytotoxic effect of three essential oils (EOs) of Origanum vulgare (OEO), Thymus vulgaris (TEO), and Coriandrum sativum (CEO) on wheat storage, but also the impact of EOs treatment on the sensory properties of bakery products obtained from the wheat seeds. The chemical composition of EOs was determined using GC-MS analysis; the fungal load was evaluated using the direct plating technique, while mycotoxin analyses were conducted using enzyme-linked immunosorbent assay (ELISA). A selective antifungal effect has been highlighted in terms of the action of EOs vapours. OEO and TEO are inhibited Alternaria, Fusarium and Drechslera, while Saccharomyces and Cladosporium have proven to be the most tolerant fungi. Drechslera is the most sensitive, the effect of all EOs being a fungicidal one. However, the fungicidal effect proved present in all EOs applied as vapours with values ranging between 0.2–0.4%. Regarding the phytotoxic effect of EOs vapours on the germination of the seeds, TEO and OEO had an inhibitory effect, especially at 0.4%. The effect is cumulative over time. The EOs inhibited deoxynivalenol (DON) occurrence; the maximum percentage of inhibition was obtained after 21 days of vapours exposure, being more effective in the case of 0.2%. EOs vapours treatment does not affect the quality of bread obtained from treated wheat seeds from a sensory point of view.

Pharmacological evaluation of anti-arthritic potential of terpinen-4-ol using in vitro and in vivo assays

Terpinen 4-ol, a phytochemical is a monoterpene which has been reported for its anti-inflammatory effect. Present research was planned to check its effect against arthritis through in vitro and in vivo models. Terpinen 4-ol was evaluated through in-vitro procedures including blocking of protein (BSA and egg albumin) denaturation and human RBC membrane stabilization. In in vivo study, terpinen 4-ol (15, 30 and 60 mg/kg) was evaluated using formaldehyde and CFA arthritic models. Terpinen 4-ol significantly inhibited increase in paw and joint swelling as compared to diseased group. Terpinen 4-ol showed remarkable antioxidant effect (SOD, reducing power) and also improved body weight, haematological, histopathological and radiological parameters in CFA model. Also, moreover, the excess production of IL-1β, TNF-α, IRAK, and NF-kB were noticeably attenuated in all terpinen 4-ol treated rats, however, IL-17 and IL-10 were distinctly increased compared to arthritic control rats in RT-PCR. Also, terpinen 4-ol showed promising antioxidant effect in DPPH assay. Henceforth, it might be concluded that terpinen 4-ol has anti-arthritic effect which can be attributed to the downregulation of pro-inflammatory cytokines.

Chemical Composition, Antioxidant, In Vitro and In Situ Antimicrobial, Antibiofilm, and Anti-Insect Activity of Cedar atlantica Essential Oil

The present study was designed to evaluate commercial cedar essential oil (CEO), obtained by hydrodistillation from cedar wood, in relationship to its chemical composition and antioxidant, in vitro and in situ antimicrobial, antibiofilm, and anti-insect activity. For these purposes, gas chromatography-mass spectrometry, DPPH radical-scavenging assay, agar and disc diffusion, and vapor phase methods were used. The results from the volatile profile determination showed that δ-cadinene (36.3%), (Z)-β-farnesene (13.8%), viridiflorol (7.3%), and himachala-2,4-diene (5.4%) were the major components of the EO chemical constitution. Based on the obtained results, a strong antioxidant effect (81.1%) of the CEO was found. CEO is characterized by diversified antimicrobial activity, and the zones of inhibition ranged from 7.33 to 21.36 mm in gram-positive and gram-negative bacteria, and from 5.44 to 13.67 mm in yeasts and fungi. The lowest values of minimal inhibition concentration (MIC) were noted against gram-positive Micrococcus luteus (7.46 µL/mL) and against yeast Candida krusei (9.46 µL/mL). It seems that the vapor phase of CEO can inhibit the growth of the microscopic filamentous fungi of the genus Penicillium according to in situ antifungal analysis on bread, carrots, and celery. This finding confirms the impact of CEO on the change in the protein structure of older biofilms of Pseudomonas fluorescens and Salmonella enterica subsp. enterica. Insecticidal activity of a vapor phase has also been demonstrated against Pyrrhocoris apterus. CEO showed various advantages on antimicrobial activity, and it is an ideal substitute for food safety.

Influence of potato variety on polyphenol profile composition and glycoalcaloid contents of potato juice

The results of studies published in recent years indicate the broad biological activity of potato juice (PJ), which is a byproduct of the starch production process. Among the most frequently described activities are anti-inflammatory, antioxidant, and cytotoxic effects. Nevertheless, this waste juice is produced by the processing of many varieties of potatoes with different proportions, which does not allow to conclude on the biological activity of individual varieties. This article is a report on the antioxidant activity of PJ from seven selected potato varieties, their profile of polyphenolic compounds, and the content of glycoalkaloids (GAs). The use of similar cultivation conditions allowed to eliminate the influence of environmental factors on the content of the analyzed compounds. The influence of PJ on the growth of probiotic, commensal, and pathogenic bacteria was also assessed. It was shown that the varieties significantly influenced the differences in antioxidant activity as well as the content of GAs, but despite the observed differences, none of them showed antimicrobial activity. Therefore, it can be concluded that an appropriately selected variety will make it possible to obtain PJ that will be characterized by high antioxidant activity and, at the same time, will be safe from the toxicological point of view.

Natural Products and Their Potential Anti-HAV Activity

The role of purified natural products in the prevention and treatment of countless diseases of bacterial, fungal, and viral origin cannot be overestimated. New antiviral drugs have been obtained from natural sources and transformed into preparations for prophylactic and therapeutic purposes. Flavonoids, polyphenols, saponins, proanthocyanins, polysaccharides, organic acids, proteins, polypeptides, and essential oils derived from plants, animals, or microorganisms can control and combat foodborne viral infections, including hepatitis A. The components of essential oils are characterized by numerous therapeutic and antioxidant properties and exhibit a broad spectrum of antimicrobial and antiviral activity. Due to these properties, they can be used to preserve meat, fruit, vegetables, and their products. Over the past two decades, much effort has been made to identify natural products, mostly of plant origin, to combat foodborne viruses. Natural plant extracts have several potential uses, not limited to increasing the safety of food products and improving their quality, but also as natural antiviral agents.

In Vitro Antimicrobial Activity of Lavender, Mint, and Rosemary Essential Oils and the Effect of Their Vapours on Growth of Penicillium spp. in a Bread Model System

The chemical composition, antioxidant activity, and antimicrobial properties of three commercially available essential oils: rosemary (REO), lavender (LEO), and mint (MEO), were determined in the current study. Our data revealed that the major components of REO, MEO, and LEO were 1,8-cineole (40.4%), menthol (40.1%), and linalool acetate (35.0%), respectively. The highest DPPH radical-scavenging activity was identified in MEO (36.85 ± 0.49%) among the investigated EOs. Regarding antimicrobial activities, we found that LEO had the strongest inhibitory efficiencies against the growth of Pseudomonas aeruginosa and Candida (C.) tropicalis, MEO against Salmonella (S.) enterica, and REO against Staphylococcus (S.) aureus. The strongest antifungal activity was displayed by mint EO, which totally inhibited the growth of Penicillium (P.) expansum and P. crustosum in all concentrations; the growth of P. citrinum was completely suppressed only by the lowest MEO concentration. The lowest minimal inhibitory concentrations (MICs) against S. enterica, S. aureus, and C. krusei were assessed for MEO. In situ analysis on the bread model showed that 125 µL/L of REO exhibited the lowest mycelial growth inhibition (MGI) of P. citrinum, and 500 µL/L of MEO caused the highest MGI of P. crustosum. Our results allow us to make conclusion that the analysed EOs have promising potential for use as innovative agents in the storage of bakery products in order to extend their shelf-life.

Biological Activity and Antibiofilm Molecular Profile of Citrus aurantium Essential Oil and Its Application in a Food Model

The main aim of the study was to investigate the chemical composition, antioxidant, antimicrobial, and antibiofilm activity of Citrus aurantium essential oil (CAEO). The biofilm profile of Stenotrophonomonas maltophilia and Bacillus subtilis were assessed using the mass spectrometry MALDI-TOF MS Biotyper and the antibiofilm activity of Citrus aurantium (CAEO) was studied on wood and glass surfaces. A semi-quantitative composition using a modified version was applied for the CAEO characterization. The antioxidant activity of CAEO was determined using the DPPH method. The antimicrobial activity was analyzed by disc diffusion for two biofilm producing bacteria, while the vapor phase was used for three penicillia. The antibiofilm activity was observed with the agar microdilution method. The molecular differences of biofilm formation on different days were analyzed, and the genetic similarity was studied with dendrograms constructed from MSP spectra to illustrate the grouping profiles of S. maltophilia and B. subtilis. A differentiated branch was obtained for early growth variants of S. maltophilia for planktonic cells and all experimental groups. The time span can be reported for the grouping pattern of B. subtilis preferentially when comparing to the media matrix, but without clear differences among variants. Furthermore, the minimum inhibitory doses of the CAEO were investigated against microscopic fungi. The results showed that CAEO was most active against Penicillium crustosum, in the vapor phase, on bread and carrot in situ.

Plant Extracts Containing Saponins Affects the Stability and Biological Activity of Hempseed Oil Emulsion System

In this study, two saponins-rich plant extracts, viz. Saponaria officinalis and Quillaja saponaria, were used as surfactants in an oil-in-water (O/W) emulsion based on hempseed oil (HSO). This study focused on a low oil phase content of 2% v/v HSO to investigate stable emulsion systems under minimum oil phase conditions. Emulsion stability was characterized by the emulsification index (EI), centrifugation tests, droplet size distribution as well as microscopic imaging. The smallest droplets recorded by dynamic light scattering (droplets size v. number), one day after the preparation of the emulsion, were around 50-120 nm depending the on use of Saponaria and Quillaja as a surfactant and corresponding to critical micelle concentration (CMC) in the range 0-2 g/L. The surface and interfacial tension of the emulsion components were studied as well. The effect of emulsions on environmental bacteria strains was also investigated. It was observed that emulsions with Saponaria officinalis extract exhibited slight toxic activity (the cell metabolic activity reduced to 80%), in contrast to Quillaja emulsion, which induced Pseudomonas fluorescens ATCC 17400 growth. The highest-stability samples were those with doubled CMC concentration. The presented results demonstrate a possible use of oil emulsions based on plant extract rich in saponins for the food industry, biomedical and cosmetics applications, and nanoemulsion preparations.