Cistus ladanifer L. essential oil as a plant based preservative against molds infesting oil seeds, aflatoxin B1 secretion, oxidative deterioration and methylglyoxal biosynthesis

Chitosan nanoemulsion incorporated with Carum carvi essential oil as ecofriendly alternative for mitigation of aflatoxin B1 contamination in stored herbal raw materials

The present investigation entails the first report on entrapment of Carum carvi essential oil (CCEO) into chitosan polymer matrix for protection of stored herbal raw materials against fungal inhabitation and aflatoxin B1 (AFB1) production. Physico-chemical characterization of nanoencapsulated CCEO was performed through Fourier transform infrared spectroscopy, dynamic light scattering, X-ray diffractometry, and scanning electron microscopy. The nanoencapsulated CCEO displayed improved antifungal and AFB1 suppressing potentiality along with controlled delivery over unencapsulated CCEO. The encapsulated CCEO nanoemulsion obstructed the ergosterol production and escalated the efflux of cellular ions, thereby suggesting plasma membrane as prime target of antifungal action in Aspergillus flavus cells. The impairment in methyglyoxal production and modeling based carvone interaction with Afl-R protein validated the antiaflatoxigenic mechanism of action. In addition, CCEO displayed augmentation in antioxidant potentiality after encapsulation into chitosan nanomatrix. Moreover, the in-situ study demonstrated the effective protection of Withania somnifera root samples (model herbal raw material) against fungal infestation and AFB1 contamination along with prevention of lipid peroxidation. The acceptable organoleptic qualities of W. somnifera root samples and favorable safety profile in mice (animal model) strengthen the application of nanoencapsulated CCEO emulsion as nano-fungitoxicant for preservation of herbal raw materials against fungi and AFB1 mediated biodeterioration.

Nanoencapsulation of garlic essential oil using chitosan nanopolymer and its antifungal and anti-aflatoxin B1 efficacy in vitro and in situ

The present study investigated the comparative efficacy of garlic essential oil (GEO) and its nanoencapsulated within chitosan nanomatrix (GEO-CSNPs) as a novel preservative for the protection of stored food commodities from fungal infestations, aflatoxin B1 (AFB1) contamination and lipid peroxidation against a toxigenic strain of Aspergillus flavus. GC-MS examination of GEO showed the presence of allyl methyl tri-sulfide (23.10 %) and diallyl sulfide (19.47 %) as the major components. GEO-CSNPs were characterized through TEM micrograph, DLS, XRD, and FTIR instrumentation. During the in-vitro investigation, GEO-CSNPs at 1.0 μL/mL dose completely inhibited the growth of A. flavus while preventing the synthesis of AFB₁ at 0.75 μL/mL compared to the pure GEO. The biochemical analysis reveals that A. flavus exposed to GEO-CSNPs significantly changed its ergosterol level, ions leakage, mitochondrial membrane potential (MMP), and antioxidant system. Additionally, GEO-CSNPs exhibited enhanced antioxidant activity against DPPH compared with GEO. Likewise, during in-situ experiments on A. hypogea GEO-CSNPs MIC and 2 MIC concentration prohibited fungal development, AFB₁ synthesis, and lipid peroxidation or inflicting any negative impacts on germinating seeds. Overall, investigations concluded that GEO-CSNPs could be used as a novel preservative agent to improve the shelf life of stored food commodities.

Encapsulation of Cymbopogon khasiana × Cymbopogon pendulus Essential Oil (CKP-25) in Chitosan Nanoemulsion as a Green and Novel Strategy for Mitigation of Fungal Association and Aflatoxin B1 Contamination in Food System

The present study deals with the encapsulation of Cymbopogon khasiana × Cymbopogon pendulus essential oil (CKP-25-EO) into a chitosan nanoemulsion and efficacy assessment for inhibition of fungal inhabitation and aflatoxin B₁ (AFB₁) contamination in Syzygium cumini seeds with emphasis on cellular and molecular mechanism of action. DLS, AFM, SEM, FTIR, and XRD analyses revealed the encapsulation of CKP-25-EO in chitosan with controlled delivery. The CKP-25-Ne displayed enhanced antifungal (0.08 µL/mL), antiaflatoxigenic (0.07 µL/mL), and antioxidant activities (IC_{50 DPPH} = 6.94 µL/mL, IC_{50 ABTS} = 5.40 µL/mL) in comparison to the free EO. Impediment in cellular ergosterol, methylglyoxal biosynthesis, and in silico molecular modeling of CKP-25-Ne validated the cellular and molecular mechanism of antifungal and antiaflatoxigenic activity. The CKP-25-Ne showed in situ efficacy for inhibition of lipid peroxidation and AFB₁ secretion in stored S. cumini seeds without altering the sensory profile. Moreover, the higher mammalian safety profile strengthens the application of CKP-25-Ne as a safe green nano-preservative against fungal association, and hazardous AFB₁ contamination in food, agriculture, and pharmaceutical industries.

Biocontrol Activity of Aromatic and Medicinal Plants and Their Bioactive Components against Soil-Borne Pathogens

Soil-borne phytopathogens can have detrimental effects on both cereal and horticultural crops resulting in serious losses worldwide. Due to their high efficiency and easy applicability, synthetic pesticides are still the primary choice in modern plant disease control systems, but stringent regulations and increasing environmental concerns make the search for sustainable alternatives more pressing than ever. In addition to the incorporation of botanicals into agricultural practices, the diversification of cropping systems with aromatic and medicinal plants is also an effective tool to control plant diseases through providing nutrients and shaping soil microbial communities. However, these techniques are not universally accepted and may negatively affect soil fertility if their application is not thoroughly controlled. Because the biocontrol potential of aromatic and medicinal plants has been extensively examined over the past decades, the present study aims to overview the recent literature concerning the biopesticide effect of secondary metabolites derived from aromatic and medicinal plants on important soil-borne plant pathogens including bacteria, fungi, and nematodes. Most of the investigated herbs belong to the family of Lamiaceae (e.g., Origanum spp., Salvia spp., Thymus spp., Mentha spp., etc.) and have been associated with potent antimicrobial activity, primarily due to their chemical constituents. The most frequently tested organisms include fungi, such as Rhizoctonia spp., Fusarium spp., and Phytophthora spp., which may be highly persistent in soil. Despite the intense research efforts dedicated to the development of plant-based pesticides, only a few species of aromatic herbs are utilized for the production of commercial formulations due to inconsistent efficiency, lack of field verification, costs, and prolonged authorization requirements. However, recycling the wastes from aromatic and medicinal plant-utilizing industries may offer an economically feasible way to improve soil health and reduce environmental burdens at the same time. Overall, this review provides comprehensive knowledge on the efficiency of aromatic herb-based plant protection techniques, and it also highlights the importance of exploiting the residues generated by aromatic plant-utilizing sectors as part of agro-industrial processes.

Preparation and characterization of a novel nanoemulsion consisting of chitosan and Cinnamomum tamala essential oil and its effect on shelf-life lengthening of stored millets

This study aimed to improve the stability of Cinnamomum tamala essential oil (CTEO) via encapsulating into chitosan nanoemulsion (CsNe) through an ionic-gelation technique and explore its food preservative efficacy against aflatoxigenic strain of Aspergillus flavus (AFLHPSi-1, isolated from stored millet), aflatoxin B₁ (AFB₁) contamination, and lipid peroxidation, causing qualitative deterioration of stored millets. The CTEO was characterized through gas chromatography-mass spectrometry (GC-MS) analysis that confirmed the presence of linalool as a major component occupying approximately 82.64% of the total oil. The synthesized nanoparticles were characterized through scanning electron microscopy (SEM), fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analysis. The encapsulation efficiency (EE) and loading capacity (LC) of CTEO-CsNe were found to be 97.71% and 3.33%, respectively. In vitro release study showed a biphasic release pattern: with an initial burst release followed by a controlled release of CTEO. During investigation of efficacy, the CTEO-CsNe caused complete inhibition of A. flavus growth, and AFB₁ biosynthesis at 1.0 and 0.8 μL/mL, respectively. The CTEO-CsNe exhibited its antifungal mode of action by altering fungal plasma membrane integrity (ergosterol inhibition) and permeability (leakage of important cellular constituents), and antiaflatoxigenic mode of action by inhibiting cellular methylglyoxal biosynthesis. CTEO-CsNe showed high free radical scavenging capacity (IC₅₀ = 5.08 and 2.56 μL/mL) against DPPH^•+ and ABTS^•+ radicals, respectively. In addition, CTEO-CsNe presented remarkable preservative efficacy, inhibiting AFB₁ and lipid peroxidation in model food system (Setaria italica) without altering their organoleptic properties. Based on overall results, CTEO-CsNe can be recommended as a novel shelf-life enhancer of stored millet samples.

Chitosan encompassed Aniba rosaeodora essential oil as innovative green candidate for antifungal and antiaflatoxigenic activity in millets with emphasis on cellular and its mode of action

The present study demonstrates first time investigation on encapsulation of Aniba rosaeodora essential oil into chitosan nanoemulsion (AREO-CsNe) with the aim of improvement of its antifungal, and aflatoxin B₁ (AFB₁) inhibitory performance in real food system. The GC–MS analysis of AREO revealed the presence of linalool (81.46%) as a major component. The successful encapsulation of EO into CsNe was confirmed through SEM, FTIR, and XRD analysis. The in-vitro release study showed the controlled release of AREO. AREO-CsNe caused complete inhibition of Aspergillus flavus (AFLHPSi-1) growth and AFB₁ production at 0.8 and 0.6 μl/ml, respectively, which was far better than AREO (1.4 and 1.2 μl/ml, respectively). Impairment of ergosterol biosynthesis coupled with enhancement of cellular materials leakage confirmed plasma membrane as the possible antifungal target of both AREO and AREO-CsNe. Significant inhibition of methylglyoxal (AFB₁ inducer) synthesis in AFLHPSi-1 cells by AREO and AREO-CsNe confirmed their novel antiaflatoxigenic mode of action. In-silico molecular docking studies revealed effective interaction of linalool with Ver-1 and Omt-A proteins, leading to inhibition of AFB₁ biosynthesis. Further, AREO-CsNe showed enhanced antioxidant activity with IC₅₀ values 3.792 and 1.706 μl/ml against DPPH^• and ABTS^•+ radicals, respectively. In addition, AREO-CsNe caused 100% protection of stored millets (Setaria italica seeds) from AFB₁ contamination and lipid peroxidation over a period of 1 year without compromising its sensory properties and exhibited high safety profile with LD₅₀ value 9538.742 μl/kg body weight. Based on enhanced performance of AREO-CsNe over AREO, it can be recommended as a novel substitute of synthetic preservative for preservation of stored millets.

Co-encapsulation of Pimpinella anisum and Coriandrum sativum essential oils based synergistic formulation through binary mixture: Physico-chemical characterization, appraisal of antifungal mechanism of action, and application as natural food preservative

The present study aimed to co-encapsulate binary synergistic formulation of Pimpinella anisum and Coriandrum sativum (PC) essential oils (0.75:0.25) into chitosan nanoemulsion (Nm-PC) with effective inhibition against fungal proliferation, aflatoxin B₁ (AFB₁) secretion, and lipid peroxidation in stored rice. Physico-chemical characterization of Nm-PC by SEM, FTIR, and XRD confirmed successful encompassment of PC inside the chitosan nanomatrix with efficient interaction by functional groups and reduction in crystallinity. Nm-PC showed superior antifungal, antiaflatoxigenic, and antioxidant activities over unencapsulated PC. Reduction in ergosterol biosynthesis and enhanced leakage of Ca²⁺, K⁺, Mg²⁺ ions and 260, 280 nm absorbing materials by Nm-PC fumigation confirmed irreversible damage of plasma membrane in toxigenic Aspergillus flavus cells. Significant diminution of methylglyoxal in A. flavus cells by Nm-PC fumigation illustrated biochemical mechanism for antiaflatoxigenic activity, suggesting future exploitation for development of aflatoxin resistant rice varieties through green transgenic technology. In silico findings indicated specific stereo-spatial interaction of anethole and linalool with Nor-1 protein, validating molecular mechanism for AFB₁ inhibition. In addition, in situ investigation revealed effective protection of stored rice against fungal occurrence, AFB₁ biosynthesis, and lipid peroxidation without affecting organoleptic attributes. Moreover, mammalian non-toxicity of chitosan entrapped PC synergistic nanoformulation could provide exciting potential for application as eco-smart safe nano-green food preservative.

Synthesis, characterization and in situ bioefficacy evaluation of Cymbopogon nardus essential oil impregnated chitosan nanoemulsion against fungal infestation and aflatoxin B1 contamination in food system

The present investigation aimed to synthesize Cymbopogon nardus essential oil impregnated chitosan nanoemulsion (Ne-CNEO) and its practical efficacy as novel green delivery system for protection of Syzygium cumini seeds against broad range storage fungi, aflatoxin B₁ (AFB₁) secretion and lipid peroxidation. Chemical characterization of CNEO revealed citral (62.73%) as major component. Successful impregnation of CNEO inside chitosan nanoemulsion was confirmed through SEM, AFM and FTIR analyses. In vitro release study showed biphasic release profile with initial burst followed by sustained release of CNEO from chitosan nanomatrix. Ne-CNEO exhibited enhancement in in vitro antifungal, antiaflatoxigenic (0.16 μL/mL) and antioxidant activity over CNEO. The antifungal and antiaflatoxigenic mechanism of action of Ne-CNEO was associated with inhibition of ergosterol biosynthesis, increased leakage of cellular contents, and impairment in cellular methylglyoxal biosynthesis. In silico modeling validated interaction of citral with Ver-1 and Omt-A proteins, confirming the molecular action for inhibition of AFB₁ production. In situ investigation suggested remarkable protection of S. cumini seeds against fungal inhabitation, AFB₁ production and lipid peroxidation without affecting organoleptic attributes. Furthermore, higher mammalian non-toxicity strengthens the application of Ne-CNEO as safe nano-green and smart preservative in place of adversely affecting synthetic preservatives in emerging food, agriculture and pharmaceutical industries.

Fabrication, characterization, and bioactivity assessment of chitosan nanoemulsion containing allspice essential oil to mitigate Aspergillus flavus contamination and aflatoxin B1 production in maize

The direct incorporation of essential oils (EOs) into real food system faces numerous challenges due to high volatility, intense aroma, and instability. This research aimed to enhance the stability and bio-efficacy of Pimenta dioica essential oil (PDEO) through encapsulation in chitosan (CN) nanoemulsion. The nanoemulsion (CN-PDEO) was fabricated through ionic-gelation technique. CN-PDEO exhibited high nanoencapsulation efficiency (85.84%) and loading capacity (8.26%) with the particle size ranging between 18.53 and 70.56 nm. Bio-efficacy assessment results showed that CN-PDEO presented more effective antifungal and antiaflatoxigenic activity against Aspergillus flavus (AF-LHP-VS8) at lower doses (1.6 and 1.0 µL/mL) than the pure PDEO (2.5 and 1.5 µL/mL, respectively, p < 0.05). Additionally, CN-PDEO preserved model food (maize) from aflatoxin B₁and lipid peroxidation without altering their sensory properties during storage with high safety profile (p < 0.05). Overall results concluded that CN-PDEO can be recommended for shelf-life extension of stored maize and other food commodities.

Prevalence of Wheat Associated Bacillus spp. and Their Bio-Control Efficacy Against Fusarium Root Rot

Bacillus spp. are the most prevalent group of bacteria in nature. Their prevalence depends upon multiple factors, namely, sporulation, antagonism, and production of secondary metabolites. The development of an eco-friendly approach to cope with edible crops diseases is very substantial for humans. In the present study, 658 isolates were obtained from wheat grown in the wheat rice cropping system and tested for their antagonistic activity against four wheat root rot pathogens, namely, Fusarium oxysporum, Fusarium moniliforme, Macrophomina phaseolina, and Rhizoctonia solani. Out of 658, 106 isolates were found antagonistic to either single or multiple fungi. Out of 106 antagonistic bacteria, 62 (23%) were rhizospheric, 28 (14%) were root endospheric, and 16 (9%) were leaf endospheric. Based on mean inhibition against all fungi, the bacterial strains SM-39 and SM-93 showed maximum antagonistic activity. The 16S rRNA gene analysis revealed that most of the antagonistic bacteria exhibiting ≥48% antagonism were Bacillus spp. (98%), except two were Klebsiella spp. (2%). The bacterial strains exhibited phylogenetic lineage with the type strains of the respective genus based on the 16S rRNA gene sequences. In the net house experiment, Bacillus velezensis (SM-39) and Bacillus cabrialesii (SM-93) significantly suppressed Fusarium root rot severity in wheat (42–62%). Plants treated with these strains had lower electrolytic leakage (29–36%), as compared to untreated (44%). Relative water content was much higher (46–58%) for plants inoculated with these strains. These antagonistic strains also considerably colonized the wheat rhizosphere with a cell population of 5.8–6.9.log CFU/g of soil. The rhizosphere of wheat grown in the wheat-rice cropping system could be the potential habitat of effective biocontrol agents.

Chemically characterized nanoencapsulated Homalomena aromatica Schott. essential oil as green preservative against fungal and aflatoxin B1 contamination of stored spices based on in vitro and in situ efficacy and favorable safety profile on mice

Present study deals with the efficacy of nanoencapsulated Homalomena aromatica essential oil (HAEO) as a potent green preservative against toxigenic Aspergillus flavus strain (AF-LHP-NS 7), storage fungi, AFB1, and free radical-mediated deterioration of stored spices. GC-MS analysis revealed linalool (68.51%) as the major component of HAEO. HAEO was encapsulated into chitosan nanomatrix (CS-HAEO-Ne) and characterized through SEM, FTIR, and XRD. CS-HAEO-Ne completely inhibited A. flavus growth and AFB1 biosynthesis at 1.25 μL/mL and 1.0 μL/mL, respectively in comparison to unencapsulated HAEO (1.75 μL/mL and 1.25 μL/mL, respectively). CS-HAEO-Ne caused significant reduction in ergosterol content in treated A. flavus and provoked leakage of cellular ions (Ca+2, Mg+2, and K+) as well as 260 nm and 280 nm absorbing materials. Depletion of methylglyoxal level in treated A. flavus cells illustrated the novel antiaflatoxigenic efficacy of CS-HAEO-Ne. CS-HAEO-Ne exhibited superior antioxidant efficacy (IC50 (DPPH) = 4.5 μL/mL) over unencapsulated HAEO (IC50 (DPPH) = 15.9 μL/mL) and phenolic content. CS-HAEO-Ne depicted excellent in situ efficacy by inhibiting fungal infestation, AFB1 contamination, lipid peroxidation, and mineral loss with acceptable sensorial profile. Moreover, broad safety paradigm (LD50 value = 7150.11 mg/kg) of CS-HAEO-Ne also suggests its application as novel green preservative to enhance shelf life of stored spices.

Chemical and Bioactive Characterization of the Essential Oils Obtained from Three Mediterranean Plants

Cupressus sempervirens L., Juniperus communis L. and Cistus ladanifer L. are Mediterranean arboreal and shrub species that possess essential oils (EO) in their leaves and branches. This study aimed at characterizing the EOs obtained by steam distillation from the three species collected in different locations from Spain (Almazán, Andévalo, Barriomartín, Cerezal, Ermitas and Huéscar). For this purpose, volatiles composition was determined by GC-MS, and different bioactivities were evaluated. The highest content in terpenes was observed in C. sempervirens (Huéscar origin) followed by J. communis (Almazán origin), corresponding to 92% and 91.9% of total compounds, respectively. With exception of C. ladanifer from Cerezal that presented viridiflorol as the most abundant compound, all the three species presented in common the α-pinene as the major compound. The EOs from C. ladanifer showed high antibacterial potential, presenting MIC values from 0.3 to 1.25 mg/mL. Concerning other bioactivities, C. ladanifer EO revealed an oxidation inhibition of 83%, while J. communis showed cytotoxicity in the MCF-7 cell line, and C. sempervirens and C. ladanifer EOs exhibited the highest potential on NCI-H460 cell lines. Nevertheless, some EOs revealed toxicity against non-tumoral cells but generally presented a GI₅₀ value higher than that of the tumor cell lines.

A Review on Cistus sp.: Phytochemical and Antimicrobial Activities

Resistance to drugs is reaching alarming levels and is placing human health at risk. With the lack of new antimicrobials drugs, infectious diseases are becoming harder to treat. Hence, there is an increasing awareness of active phytochemicals with therapeutic functions. The tremendous research interest on the Cistus L. genus includes numerous plants used in traditional medicine by people living around the Mediterranean Sea, also resulted in some interesting discoveries and written literature. This review aimed at gathering scientific literature about Cistus species, describing phytochemical profiles and the various pharmacological activities. We also extensively reviewed the antimicrobial activities, including antiviral, antiparasitic, antifungal, and antibacterial potentials of Essential Oils (EO), raw extracts as well as isolated compounds. Mechanisms of action along with methods used are also investigated in this review. Considering the findings of the Cistus species extracts, this genus offers an adequate reserve of active phytochemicals since many have been used to create drugs. Therefore, this review work can serve society by providing a global view on Cistus L. sp. regarding pharmacological potentials and their chemical profiles.

Essential Oils from Residual Foliage of Forest Tree and Shrub Species: Yield and Antioxidant Capacity

Increasing applications and markets for essential oils could bring new opportunities for cost-effective and sustainable management of unused forestry biomass; however, better knowledge of the production and application of such essential oils is necessary. The objective of this work is to contribute to greater knowledge of the essential oil production on a pilot scale from foliage biomass of wild shrubs and tree residues produced in some forestry enhancement operations and to study their antioxidant capacity (ORAC-oxygen radical absorbance capacity). Fresh biomass (twigs) of seven species (E. globulus, E. nitens, P. pinaster, P. sylvestris, R. officinalis, C. ladanifer, and J. communis) was manually collected in Spain in two different periods and was ground at 30 mm and distilled in a 30 L stainless steel still with saturated steam. The essential oil components were identified by GC-MS and quantified by GC-FID, and their antioxidant activity was determined with the ORAC method. Promising results on essential oil yield were obtained with E. globulus, E. nitens, R. officinalis, and J. communis. All essential oils studied exhibited antioxidant capacity by the ORAC assay, particularly that from C. ladanifer. Moreover, oxygenated sesquiterpenes contents, one of the minor components of oils, were significantly correlated with ORAC values.

Essential Oils and Their Application in Food Safety

Food industries are facing a great challenge due to contamination of food products with different microbes such as bacteria, fungi, viruses, parasites, etc. These microbes deteriorate food items by producing different toxins during pre- and postharvest processing. Mycotoxins are one of the most potent and well-studied toxic food contaminants of fungal origin, causing a severe health hazard to humans. The application of synthetic chemicals as food preservatives poses a real scourge in the present scenario due to their bio-incompatibility, non-biodegradability, and environmental non-sustainability. Therefore, plant-based antimicrobials, including essential oils, have developed cumulative interest as a potential alternative to synthetic preservatives because of their ecofriendly nature and generally recognized as safe status. However, the practical utilization of essential oils as an efficient antimicrobial in the food industry is challenging due to their volatile nature, less solubility, and high instability. The recent application of different delivery strategies viz. nanoencapsulation, active packaging, and polymer-based coating effectively addressed these challenges and improved the bioefficacy and controlled release of essential oils. This article provides an overview of essential oils for the preservation of stored foods against bacteria, fungi, and mycotoxins, along with the specialized mechanism of action and technological advancement by using different delivery systems for their effective application in food and agricultural industries smart green preservative.

Edible flower essential oils: A review of chemical compositions, bioactivities, safety and applications in food preservation

In the context of consumers' growing concerns and boycotts of artificial and harmful chemicals, satisfying the demands for good-quality food products possessing clean and safe images is a challenge for food industry. Due to natural and avirulent images, various bioactivities as well as potentials to be used as safer substitutes for chemical preservatives, flower essential oils (EOs) have aroused increasing interests in the recent past. Many literatures have verified the biological activities of flower EOs, and have given high value to the preservative potentials of flower EOs in food systems. In this work, a review is done on the most recent publications associating the chemical constituents, bioactivities (antibacterial, antifungal, antioxidant and anti-pest abilities) and safety of flower EOs. The effects of flower EOs on food flavor are also discussed. Finally, the current combined preservation applications of flower EOs and other technologies are summarized.

Nanoencapsulation of essential oils and their bioactive constituents: A novel strategy to control mycotoxin contamination in food system

Spoilage of food by mycotoxigenic fungi poses a serious risk to food security throughout the world. In view of the negative effects of synthetic preservatives, essential oils (EOs) and their bioactive constituents are gaining momentum as suitable substitute to ensure food safety by controlling mycotoxins. However, despite their proven preservative potential against mycotoxins, the use of EOs/bioactive constituents in real food system is still restricted due to instability caused by abiotic factors and negative impact on organoleptic attributes after direct application. Nanoencapsulation in this regard could be a promising approach to address these problems, since the process can increase the stability of EOs/bioactive constituents, barricades their loss and considerably prevent their interaction with food matrices, thus preserving their original organoleptic qualities. The aim of this review is to provide wider and up-to-date overview on recent advances in nanoencapsulation of EOs/bioactive constituents with the objective to control mycotoxin contamination in food system. Further, the information on polymer characteristics, nanoencapsulation techniques, factors affecting the nanoencapsulation, applications of nanoencapsulated formulations, and characterization along with the study on their release kinetics and impacts on organoleptic attributes of food are discussed. Finally, the safety aspects of nanoencapsulated formulations for their safe utilization are also explored.

Assessment of nanoencapsulated Cananga odorata essential oil in chitosan nanopolymer as a green approach to boost the antifungal, antioxidant and in situ efficacy

In this study, a comparative efficacy of Cananga odorata EO (CoEO) and its nanoencapsulated formulation into chitosan nanoemulsion (CoEO-CsNe) against a toxigenic strain of Aspergillus flavus (AF-M-K5) were investigated for the first time in order to determine its efficacy in preservation of stored food from fungal, aflatoxin B₁ (AFB₁) contamination and lipid peroxidation. GC and GC-MS analysis of CoEO revealed the presence of linalool (24.56%) and benzyl acetate (22.43%) as the major components. CoEO was encapsulated into chitosan nanoemulsion (CsNe) through ionic-gelation technique and characterized by High Resolution-Scanning Electron Microscopy (HR-SEM), Fourier Transform Infrared spectroscopy (FTIR), and X-Ray Diffraction (XRD) analysis. The CoEO-CsNe during in vitro investigation against A. flavus completely inhibited the growth and AFB₁ production at 1.0 μL/mL and 0.75 μL/mL, respectively. Additionally, CoEO-CsNe showed improved antioxidant activity against DPPH^• and ABTS^•+ with IC₅₀ value 0.93 and 0.72 μL/mL, respectively. Further, CoEO-CsNe suppressed fungal growth, AFB₁ secretion and lipid peroxidation in Arachis hypogea L. during in situ investigation without causing any adverse effect on seed germination. Overall results demonstrated that the CoEO-CsNe has potential of being utilized as a suitable plant based antifungal agent to improve the shelf-life of stored food against AFB₁ and lipid peroxidation mediated biodeterioration.

Catalyzed Steam Gasification of Cistus Ladanifer Biochar

Gasification processes require the use of cheap and sustainable raw materials, as well as the optimization of the process, for a suitable commercial use. Cistus Ladanifer (rockrose) could be a suitable raw material for this purpose, as it grows spontaneously in Mediterranean regions, and might contribute to the economic development of these areas. In this research, a study about catalyzed gasification of Cistus Ladanifer biochar was carried out. The aim was to characterize the gaseous phase and to carry out a kinetic study. The experiments were carried out in a thermobalance connected to a gas chromatograph to quantify the exhaust gas. The operating variables studied were the initial carbon mass, temperature, steam partial pressure, the kind of catalyst (ionic or cationic), catalyst concentration and the method to incorporate the catalyst (impregnation or mixture). As a result, impregnation was the most effective way to mix the raw material and the catalyst, with K+ and CO32− as the most active cations and anions used in this experience, respectively. Temperature and steam partial vapor showed a positive effect on conversion and gas yield. The use of ideal models for gas-solid reactions showed acceptable results for the kinetic study.

Eugenol loaded chitosan nanoemulsion for food protection and inhibition of Aflatoxin B1 synthesizing genes based on molecular docking

The present investigation entails the fabrication and characterization of nanometric emulsion of eugenol (Nm-eugenol) encompassed into chitosan for assessing bio-efficacy in terms of in vitro antifungal actions, antiaflatoxigenic potential, and in situ preservative efficacy against Aspergillus flavus infestation and aflatoxin B₁ (AFB₁) mediated loss of dietary minerals, lipid triglycerides and alterations in composition of important macronutrients in stored rice. Nm-eugenol characterized by SEM, XRD, and FTIR exhibited biphasic burst release of eugenol. Reduction in ergosterol and methylglyoxal (AFB₁-inducer) content after Nm-eugenol fumigation depicted biochemical mechanism of antifungal and antiaflatoxigenic activities. In silico 3D homology docking of eugenol with Ver-1 gene validated molecular mechanism of AFB₁ inhibition. Further, significant protection of rice seeds from fungi, AFB₁ contamination and preservation against loss of rice minerals, macronutrients and lipids during storage suggested deployment of chitosan as a biocompatible wall material for eugenol encapsulation and application as novel green preservative for food protection.

Pullulan Films Containing Rockrose Essential Oil for Potential Food Packaging Applications

Active packaging is designed to control the development of decay- and disease-causing microorganisms and is emerging as a promising technology for extending shelf-life, maintaining food safety, reducing waste, and minimizing the risks for foodborne diseases. The goal of this work was to develop and characterize bioactive pullulan-based films, containing rockrose (Cistus ladanifer) essential oil. Among other abundant compounds (camphene, bornyl acetate and trans-pinocarveol), α-pinene was identified as the major compound of rockrose essential oil (39.25%). The essential oil presented stronger antibacterial activity against Gram-positive than against Gram-negative bacteria. The antioxidant results indicate the potential of the developed films to be used to package foods susceptible to oxidation and rancification, thus improving their shelf-life. Also, this study reflects the potential of rockrose essential oil, free or incorporated in pullulan, as a promising quorum sensing inhibitor, since it was able to interrupt intercellular communication, inhibiting violacein production. Electronic microscopy images showed the antibiofilm activity of the films with rockrose essential oil that were able to influence bacterial adhesion, which may be explained by the differences in the surface free energy of the films, as also determined.

Assessment of preservative potential of Bunium persicum (Boiss) essential oil against fungal and aflatoxin contamination of stored masticatories and improvement in efficacy through encapsulation into chitosan nanomatrix

The study reports the preservative efficacy of Bunium persicum (Boiss) essential oil (BPEO) against fungal and aflatoxin B₁ (AFB₁) contamination of stored masticatories and boosting of its efficacy through encapsulation into chitosan. BPEO was chemically characterized through GC-MS analysis, which revealed γ-terpinene as the major compound. The BPEO at 1.2 μL/mL concentration completely inhibited the growth of toxigenic strain of Aspergillus flavus (AF-LHP-PE-4) along with 15 common food borne moulds and AFB₁ secretion. The BPEO exerts its antifungal action on plasma membrane, as confirmed through ergosterol inhibition, alteration of membrane fluidity and enhancement of cellular ions and 260 and 280 nm absorbing material leakage. The antiaflatoxigenic mechanism of action of BPEO was confirmed through methylglyoxal reduction. Further, BPEO showed strong antioxidant activity (IC₅₀ = 7.36 μL/mL) as measured by DPPH^· assay. During in situ investigation, BPEO completely inhibited AFB₁ production in model food (Phyllanthus emblica) system without altering the sensory properties and also exhibited high LD₅₀ value (14,584.54 μL/kg) on mice. In addition, BPEO was encapsulated into chitosan, characterized and tested for their potential to inhibit growth and AFB₁ production. The mean particle size, PDI and zeta potential of formed BPEO-loaded chitosan nanoparticle (CS-Np-BPEO) were performed to confirm successful encapsulation. The result revealed nanoencapsulated BPEO showed enhanced activity and completely inhibited the growth and AFB₁ production by AF-LHP-PE-4 at 0.8 μL/mL. Based on findings, it could be concluded that the BPEO and its encapsulated formulation can be recommended as a potential plant-based preservative against fungal and aflatoxin contamination of stored masticatories.

Nanoencapsulated Monarda citriodora Cerv. ex Lag. essential oil as potential antifungal and antiaflatoxigenic agent against deterioration of stored functional foods

In vitro antifungal activity of the essential oil from Monarda citriodora (MCEO) with possible mode of action was evaluated against A. flavus (AF-LHP-SH1) and 15 other storage molds for controlling postharvest deterioration of stored functional food samples. The chemical profiling of MCEO as done through GC-MS analysis revealed caryophyllene (19.15%) as the major component. The MCEO showed broad spectrum fungitoxicity and completely inhibited the growth of all tested molds and aflatoxin B₁ (AFB₁) production by AF-LHP-SH1 at 1.40 and 1.20 µL/mL, respectively. Plasma membrane damage and methylglyoxal inhibition was confirmed as the possible antifungal and antiaflatoxigenic mode of action of MCEO. MCEO exhibited remarkable antioxidant activity with IC₅₀ value 2.24 μL/mL as determined through DPPH assay and did not cause adverse effect on seed germination. In addition, the MCEO was encapsulated into chitosan nanoparticle, characterized (SEM, FTIR, XRD) and assessed for their potential against inhibition of growth and AFB₁ production. MCEO after encapsulation exhibited enhanced efficacy inhibiting fungal growth and AFB₁ production by AF-LHP-SH1 at 0.6 and 0.5 µL/mL, respectively. Encapsulated MCEO may be recommended as novel preservative to extend the shelf life of stored functional food samples.

Multitrait Pseudomonas spp. Isolated from Monocropped Wheat (Triticum aestivum) Suppress Fusarium Root and Crown Rot

Fusarium root and crown rot is the most common disease of wheat, especially wheat grown in arid zones where drought is a common issue. The development of environmentally safe approaches to manage diseases of food crops is important for humans. The monocropping system recruits beneficial bacteria that promote plant growth through nutrient solubilization and pathogen suppression. In this study, a field where wheat was monocropped for 5 successive years under rainfed conditions was identified. A total of 29 bacterial isolates were obtained from the rhizosphere, endosphere, and phyllosphere of wheat at its harvesting stage. The Gram-negative bacteria were less prevalent (41%) but the majority (75%) exhibited plant growth-promoting traits. The ability of strains to solubilize nutrients (solubilization index = 2.3 to 4), inhibit pathogenic fungi (25 to 56%), and produce antifungal compounds was highly variable. The rhizobacteria significantly promoted the growth and disease resistance of wheat varieties such as Pirsbak-2015 and Galaxy-2013 by inducing antioxidant enzyme activity (0.2- to 2.1-fold). The bacterial strains were identified as Ochrobactrum spp., Acinetobacter spp., and Pseudomonas mediterranea by 16S rRNA and rpoD sequence analysis. The endophytic bacterium P. mediterranea HU-9 exhibited maximum biocontrol efficacy against wheat root and crown rot diseases with a disease score/disease index from 1.8 to 3.1. The monocropping systems of rainfed agriculture are an ideal source of beneficial bacteria to use as bioinoculants for different crops.

Antimicrobial activity, antiaflatoxigenic potential and in situ efficacy of novel formulation comprising of Apium graveolens essential oil and its major component

The present study reports the formulation of Apium graveolens essential oil (AGEO) with its major components linalyl acetate (LA) and geranyl acetate (GA) (1:1:1) as a novel green preservative for protection of postharvest food commodities from fungal infestations, aflatoxin B₁ (AFB₁) secretion, free radical generation and lipid peroxidation. The essential oil based novel formulation displayed considerable inhibitory action against fourteen food borne molds responsible for deterioration of stored food commodities, in addition to the most toxigenic strain of Aspergillus flavus (AFLHPR14) isolated from fungal and aflatoxin contaminated rice seeds. The observed higher efficacy of designed formulation was due to the synergistic action of essential oil and its major components. Fungal plasma membrane was recorded as the possible target site of antifungal action of the formulation as revealed through reduction in membrane ergosterol content, increased intracellular propidium iodide (PI) fluorescence and enhanced leakage of cellular ions (sodium, potassium, calcium) and 260, 280 nm absorbing materials. Further, inhibition of methylglyoxal (an aflatoxin inducer) confirmed the aflatoxin inhibitory potential of novel formulation based on essential oil and its major components. High antioxidant potential as observed through DPPH and ABTS^·+ radical scavenging assay, improved phenolic content, considerable inhibition of lipid peroxidation in stored rice seeds, in situ efficacy on AFB₁ inhibition in food system under storage container system, acceptable sensorial characteristics and favorable safety profile during animal trials suggest the recommendation of the designed formulation for large scale application as green preservative by food and agriculture based industries against fungal and aflatoxin contamination of stored commodities.

Essential oils and their bioactive compounds as green preservatives against fungal and mycotoxin contamination of food commodities with special reference to their nanoencapsulation

Fungal and mycotoxin contamination of stored food items is of utmost concern throughout the world due to their hazardous effects on mammalian systems. Most of the synthetic chemicals used as preservatives have often been realised to be toxic to humans and also cause adverse environmental effects. In this respect, use of different plant products especially essential oils (EOs) and their bioactive compounds has been recognized as a green strategy and safer alternatives to grey synthetic chemicals in view of their long traditional use. The current nanoencapsulation technology has strengthened the prospective of EOs and their bioactive compounds in food preservation by enhancing their bioactivity and mitigating other problems regarding their large-scale application. Although, the antimicrobial potential of EOs and their bioactive compounds has been reviewed time to time by different food microbiologists, but very less is known about their mode of action. Based on these backgrounds, the present article provides an account on the antifungal and antimycotoxigenic mode of action of EOs as well as their bioactive compounds. In addition, the article also deals with the application of currently used nanoencapsulation approach to improve the stability and efficacy of EOs and their bioactive compounds against mycotoxigenic fungi causing deterioration of stored food items so as to recommend their large-scale application for safe preservation and enhancement of shelf life of food items during storage.

Assessment of Melissa officinalis L. essential oil as an eco-friendly approach against biodeterioration of wheat flour caused by Tribolium castaneum Herbst

The study reports efficacy of Melissa officinalis L. essential oil (MOEO) as a safe plant-based insecticide against Tribolium castaneum Herbst (TC) by induction of oxidative stress. MOEO nanoencapsulation in chitosan matrix was performed to enhance its bioefficacy. GC-MS analysis of MOEO depicted geranial (31.54%), neral (31.08%), and β-caryophyllene (12.42%) as the major components. MOEO showed excellent insecticidal potential in contact (100% mortality at 0.157 μL/cm²) and fumigant bioassays (LC₅₀ = 0.071 μL/mL air) and 100% repellency at concentration ≤ 0.028 μL/cm². Increased reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), and decreased ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) at the LC₅₀ dose suggested significant oxidative stress on TC in MOEO treatment sets. The encapsulated MOEO exhibited enhanced activity as fumigant (LC₅₀ = 0.048 μL/mL air) and showed significant antifeedant activity in situ (EC₅₀ = 0.043 μL/mL). High LD₅₀ value (13,956.87 μL/kg body weight of mice) confirmed favorable toxicological profile for non-target mammals. The findings depict potential of nanoencapsulated MOEO as an eco-friendly green pesticide against infestation of stored food by TC.