Search Results (35)

Citrus fruits are major economic and nutritional crops that are sometimes subjected to serious attacks by many fungal phytopathogens after harvesting. In this study, we focus on the structures of potential antifungal nanocomposites from artichoke leaf extract (Art), Art-mediated nanosilver (AgNPs), and their nanoconjugates with chitosan nanoparticles (Cht) to eradicate the blue mold fungus (Penicillium italicum) and preserve oranges during storage via nanocomposite-based edible coatings (ECs). The biosynthesis and conjugation of nanomaterials were verified using UV and infrared (FTIR) spectroscopy, electron microscopy (TEM and SEM) analysis, and DLS assessments. Art could effectually biosynthesize/cap AgNPs with a mean size of 10.35 nm, whereas the average size of Cht was 148.67 nm, and the particles of their nanocomposites had average diameters of 203.22 nm. All nanomaterials/composites exhibited potent antifungal action toward P. italicum isolates; the Cht/Art/AgNP nanocomposite was the most effectual, with an inhibition zone of 31.1 mm and a fungicidal concentration of 17.5 mg/mL, significantly exceeding the activity of other compounds and the fungicide Enilconazole (24.8 mm and 25.0 mg/mL, respectively). The microscopic imaging of P. italicum mycelia treated with Cht/Art/AgNP nanocomposites emphasized their action for the complete destruction of mycelia within 24 h. The orange (Citrus sinensis) fruit coatings, with nanomaterial-based ECs, were highly effectual for preventing blue mold development and preserved fruits for >14 days without any infestation signs; when the control infected fruits were fully covered with blue mold, the infestation remarks covered 12.4%, 5.2%, and 0% of the orange coated with Cht Art/AgNPs and Cht/Art/AgNPs. The constructed Cht/Art/AgNP nanocomposites have potential as effectual biomaterials for protecting citrus fruits from fungal deterioration and preserving their quality. Full article

Microbial contamination challenges have led to the development of active edible coatings for fruit preservation. Herein, a Konjac glucomannan (KGM) coating loaded with Ocimum gratissimum (OG) essential oil stabilized by pectin with superior resistance to air permeability, oxidation, and fungal, was prepared in situ on the surface of Mandarin oranges to enhance postharvest fruit quality. The results demonstrated that the KGM-pectin-OG (K-P-OG) 1.5 wt% coating exhibited good performance in terms of stability, adhesion, and wetting. Meanwhile, the coating had an ideal air permeability due to its compact and dense structure based on the good compatibility and interactions between the components. The oxygen permeability of the K-P-OG coating was 7.9 × (10⁻¹⁶ g·cm)/(cm²·s·Pa), which was six orders of magnitude lower than that of the KGM coating. The antioxidant, in vitro, and in vivo antifungal activities against Penicillium italicum of the coating were strengthened by the OG emulsion and mainly depended on its concentration. The storage results showed that the K-P-OG 1.5% coating extended the shelf life of Mandarin oranges by 8 days, reduced the weight loss rate by 13%, and increased the firmness and POD during storage by 24.14% and 100%, respectively, compared with the control group. These results demonstrate that K-P-OG can effectively maintain nutrient content and extend the storage time of Mandarin oranges by enhancing antioxidant capacity and inhibiting fruit respiration and microorganism growth. This study presents a strategy for developing edible coatings for postharvest fruit preservation. Full article

The antifungal efficacy of coffee residue extract (CRE) and chitosan nanoparticles (CNPs) alone and in combination (CNPs-CRE) against the growth of Rhizopus stolonifer was assessed. Two nanostructured edible coatings (ECs), one consisting of chitosan nanoparticles (CCNP) and another consisting of coffee residue extract encapsulated in chitosan nanoparticles (CCNP-CRE), were elaborated, characterized, and applied on inoculated Naples tomatoes to evaluate their fungicidal activity and their effect on fruit quality. The tests consisted of evaluating physicochemical variables in tomato previously sprayed with CCNP and CCNP-CRE for 30 days preharvest and 14 days at 10 °C postharvest. CNPs with a particle size of 2.4 ± 0.24 nm with a Z potential of −1.62 mV were observed, while CNPs-CRE showed a size of 3.9 ± 0.55 nm with a Z potential of −0.89 mV. The FTIR spectrum showed the integration of CRE into the CCNP-CRE. A synergistic effect between CNPs and 1% CRE was observed, obtaining the greatest inhibition of mycelial growth (43%). In the preharvest trials, both ECs showed differences with respect to the control in the variables of color, total carotenoids and ethylene. In the postharvest test, they showed differences in color and CO₂ production. The severity of the infection decreased by 33% in tomatoes with coatings. The ECs evaluated represent a emergent technological advancement in the conservation of the tomato. Full article

Active packaging has emerged as a promising technological alternative for coating fruits and extending their shelf life. In this study, we developed a Tara gum and chitosan nanostructure-based coating, assessing its effects on guava shelf life and antifungal activity. In vitro analyses showed that nanochitosan suspension concentrations between 4.5 and 5.625 mg·mL⁻¹ completely inhibited the growth of the fungus Colletotrichum gloeosporioides and reduced the growth of Puccinia psidii. In in vivo tests, guavas coated with a 1.5% (w/v) Tara gum coating with 0.5% (v/v) nanochitosan exhibited significantly delayed or no lesion growth, unlike the control group, where lesions developed continuously. Beyond antifungal results, the Tara gum and nanochitosan coatings maintained the guava’s luminescence for up to 16 days, reduced weight loss, and preserved firmness compared to the control group. Firmness tests indicated that Tara gum, both pure and at 0.1% and 0.3% (v/v) concentrations, was effective in preserving this characteristic. Chemically, the coating also contributed to increased pH and acidity of the guavas, although a reduction in reducing and total sugars was observed in all groups. These findings confirm that the Tara gum with nanochitosan-based coating is an effective nanotechnological biomaterial to extend the shelf life of seasonal fruits, acting as a physical and biological barrier against pathogens and supporting post-harvest preservation. Full article

Edible oils work to protect the fruit in more than one way. They act as a barrier or insulating layer that prevents moisture loss from the fruits, prevents the development of microbes on the surface, prevents chemical changes in the fruits, and prevents the deterioration of the fruits. These functions work to improve the quality of the fruits and increase the shelf life of the fruits. Medjool date palm fruits experience post-harvest difficulties such as weight loss, reduced taste, microbial contamination, and general quality degradation during storage, particularly at room temperature. Essential oils with antibacterial, antifungal, and antioxidant qualities, such as jasmine oil, black cumin oil, and jojoba oil, have demonstrated significant promise for improving fruit storability and quality. The purpose of this study is to investigate the effects of treatment with edible coating with jasmine oil, black cumin oil, and jojoba oil of Medjool date palm fruits under room storage conditions to lengthen shelf life, preserve quality, and reduce refrigeration during the seasons of 2021 and 2022. The study treatments were jasmine oil 1.5%, black cumin oil 1.5%, jojoba oil 7%, and untreated fruits as a control. Data showed that treatment with edible coating with jojoba oil reduced Medjool date palm fruit decay percentages and weight loss, delayed skin separation, and improved chemical fruit properties such as total sugar and total soluble solids (TSS%), followed by black cumin oil and then jasmine oil. The results showed that using jasmine oil, black cumin oil, or jojoba oil as a layer of essential oils provides a realistic option to enhance storability, extend shelf life, maintain quality, and reduce refrigeration in Medjool date palm fruits. Full article

The use of lactic acid bacteria (LAB) for the probiotic enrichment of minimally processed fruit is a well-established practice in the literature. In addition, several LAB demonstrated a strain-specific ability to control harmful microorganisms and decay agents, improving shelf life, maintaining quality, and promoting the safety of fruits and vegetables. Edible coatings can help modulate the phenomena of gas exchange and water loss by fruits, representing protection from physical damage and spoilage phenomena linked to oxidation and the development of undesired microorganisms. At the same time, the coating can represent an innovative delivery matrix for the LAB strains of potential interest to improve safety and quality in the postharvest management of fruits. In this work, five Lactiplantibacillus plantarum strains, previously characterised for their probiotic and antifungal activity, were incorporated into a sodium alginate coating to develop edible probiotic coatings with antifungal properties for table grapes cv. Italia. The bacterial transfer and their survival were evaluated by comparing coated and uncoated table grapes during 14 days of cold storage at 4 °C. The alginate edible coating increased the number of viable cells transferred to the surface of the berries from about 5 to more than 7 Log CFU/g, with a crucial impact on the potential functional attributes of the final product. The ability of the functionalised coatings to counteract the decay development was evaluated on table grape berries artificially contaminated with Aspergillus niger CECT 2805. A significant reduction in lesion diameter was observed in the alginate coating with L. plantarum 11-A, with a reduction from 15.40 ± 1.14 mm of uncoated berries to 8.40 ± 1.14 mm of berries coated with L. plantarum 11-A. The lesion diameter reduction was also accompanied by a reduction in the symptoms of infection, such as browning around the wound. These results suggest the application of selected strains of L. plantarum as promising bio-resources to enhance the overall value of ready-to-eat fruits and vegetables, particularly in combination with edible coating as a carrier matrix. While a strain-dependent effect was not detected with respect to the improvement in the number of cells in the edible coating, a variability depending on the biotype used was detected for the properties linked to biocontrol, suggesting that the inclusion in edible packaging may represent an innovative criterion in the selection of lactobacilli to be applied postharvest. Full article

Plant extracts (PEs) are natural substances that perform interesting bioactivities. However, they have some limitations. In this work, PEs from licorice, eucalyptus, sage, and thyme were produced and characterized. These extracts showed good bioactive properties. Alginate-based edible coatings and films incorporated with the extracts were produced and their antimicrobial and antioxidant properties were determined. The results showed that the coatings completely inhibited or reduced the growth of all bacteria (E. coli, P. aeruginosa, B. cereus, L. monocytogenes, and S. aureus), except the coating with sage extract. However, only the films incorporated with licorice and eucalyptus could inhibit the growth of Gram-positive bacteria and none of the films were able to inhibit Gram-negative bacteria. The film incorporated with sage extract was the one with the best antifungal property. All films possess a good antioxidant property (ABTS: 942.52–5654.62; DPPH: 1040.67–5162.93 Trolox equivalents (µM)/mg film). Based on the results, it is possible to conclude that alginate coatings and films with PEs present good bioactive properties and can potentially be used as new, biodegradable packages. However, further experiments need to be performed to assess their safety profile, and to prove that they can be a real alternative to traditional food packaging. Full article

Sour rot, caused by Geotrichum citri-aurantii, can produce significant postharvest losses of citrus fruits and, currently, cannot be effectively controlled by the postharvest fungicides registered in EU countries. Therefore, novel antifungal edible coatings (ECs) based on citrus pectin and beeswax and enriched with eugenol (EG), geraniol (GR), propolis extract (PR) or essential oils (EOs) from Satureja montana (SA), Cinnamomum zeylanicum (CI), or Commiphora myrrha (CM), were developed as alternatives to reduce sour rot and preserve the postharvest quality of ‘Valencia’ oranges. These natural agents were incorporated into the EC formulation and then applied to inoculated oranges. ECs enriched with EG (2–8 g/kg), GR (4 and 8 g/kg), PR (5–20 g/kg), and CM EO (15 g/kg) reduced disease incidence and severity by 75 to 100% compared to uncoated oranges after 20 days of incubation at 20 °C. ECs containing EG (8 g/kg), GR (4 g/kg), and PR (20 g/kg) reduced weight loss and retained firmness of oranges after 14 days of shelf life at 20 °C. Furthermore, all tested ECs maintained the fruit’s sensory and physicochemical quality. Overall, the EG-enriched pectin EC performed best, showing potential as a safe, bio-based alternative to conventional waxes containing synthetic fungicides for the management of citrus postharvest sour rot. Full article

In this study, the effect of hydroxypropyl methylcellulose (HPMC) and gum Arabic (GA) edible coatings amended with 0.2% geraniol (GE) were evaluated for the control of brown rot, caused by Monilinia fructicola, on artificially inoculated plums (Prunus salicina Lindl., cv. Angeleno) stored for 5 weeks at 1 °C. Brown rot is the most important pre- and postharvest fungal disease of stone fruits, causing severe economic losses worldwide. Geraniol is an important constituent of many essential oils that can be obtained as a byproduct from different industrial procedures, such as those of the juice industry. Fruit postharvest quality was also evaluated after 5 and 8 weeks of storage at 1 °C, followed by 3 days at 7 °C plus 5 days at 20 °C, simulating packinghouse, transport, and retail shelf-life conditions, respectively. HPMC coatings containing 0.2% GE reduced the incidence and severity of brown rot by 37.5 and 64.8%, respectively, compared to uncoated fruit after 5 weeks of storage at 1 °C. HPMC-coated plums, with and without GE, showed the highest level of firmness, the lowest change in external peel color parameters (L*, a*, b*, C*, hue), and the lowest flesh bleeding compared to uncoated control and GA-coated samples throughout the entire storage period, which correlated with a higher gas barrier of these coatings without negatively affecting sensory quality. Furthermore, the HPMC-0.2% GE coating provided the highest gloss to coated plums, showing the potential of this coating as a safe and environmentally friendly alternative to conventional fungicides and waxes for brown rot control and quality maintenance of cold-stored plums. Full article

Opuntia dillenii (O. dillenii) is a plant belonging to the Cactaceae family that is abundant in tropical and subtropical regions worldwide. O. dillenii is consumed as a local delicacy and has no other current use. To understand the nutritional value of O. dillenii in human health and its application in the food, cosmetic, and drug industries, this review summarizes information on the chemical compounds (pure α-pyrone compounds, flavonoids, phenolic acids, polysaccharides, minerals, fatty acids, and betalains) and biological properties (anti-diabetic, anti-hyperglycemic, antihyperlipidemic, anti-atherosclerotic, anti-inflammatory, analgesic, antimicrobial, antifungal, antiviral, anti-spermatogenic, anticancer, antilarval, anti-angiogenic, and antioxidant) of extracts from each part of the plant (fruit juice, fruit peel, cladode, and seeds) (aqueous, ethanolic, and methanolic), and seed oil. In addition, data related to the recent applications of O. dillenii in various industries (e.g., edible coatings, food supplements, cosmetics, nanoparticles, and wastewater treatment) are provided. Full article

Application of hydrophobic coatings, such as carnauba wax nanoemulsions, combined with natural antimicrobials, has been demonstrated to be an effective solution in extending the shelf life of fruits. The present study evaluated the effectiveness of carnauba wax nanoemulsion (CWN) coatings containing free or encapsulated with β-cyclodextrin (β-CD) essential oils of Syzigium aromaticum (CEO) and Mentha spicata (MEO) for the post-harvest conservation of papaya fruit. The chemical composition of the essential oils (EOs) was analyzed using GC-MS. Subsequently, coatings incorporating free and encapsulated EOs were prepared and applied to papaya fruit. Fruit was evaluated for post-harvest quality parameters during 15 days of storage. Clove essential oil presented as main compounds eugenol (89.73%), spearmint and carvone (68.88%), and limonene (20.34%). The observed reduction in weight loss in coated fruit can be attributed to the formation of a physical barrier provided by the coating. Compared to the control group, which experienced the highest weight loss of 24.85%, fruit coated with CWN and CWN-MEO:β-CD exhibited significantly lower weight loss percentages of only 5.78% and 7.5%, respectively. Compared to the control group, which exhibited a release of ethylene at a rate of 1.3 µg kg⁻¹ h⁻¹, fruit coated with CWN, CWN-MEO:β-CD, and CWN-MEO coatings demonstrated a lower ethylene release rate at 0.7 µg kg⁻¹ h⁻¹. Although the physical-chemical properties of papayas, including pH, Brix, titratable acidity, color, and texture, remained largely unchanged during storage with the coatings, analysis of incidence and severity of papaya post-harvest deterioration revealed that coatings containing essential oils effectively acted as antifungals in the fruit. Microscopy images showed that CWN and CWN-MEO:β-CD coatings are more uniform compared to the others. The edible coatings, especially CWN and CWN-MEO: β-CD, can act as antimicrobial coatings on papaya fruit, increasing their conservation during post-harvest storage. Full article

Apple fruits are susceptible to pathogenic fungi such as Botrytis cinerea and Penicillium expansum which are responsible for significant pre- and postharvest fruit losses. Given the strong restriction in the use of synthetic agrochemicals, especially during the postharvest phase, alternatives are currently sought for a more sustainable management of apple storage. The antifungal activity of thyme, clove, anise, camphor, and juniper essential oils (EOs) was evaluated with in vitro tests and the minimum inhibitory concentration (MIC) was determined. Thyme and anise EOs showed a MIC value of 0.5 and 1 mL L⁻¹ against B. cinerea, respectively. A MIC of 0.5 mL L⁻¹ was found for clove EO against P. expansum. Camphor and juniper EOs were found to be less effective. Although in those experiments the antifungal activity of EOs was proven, when EOs were applied in in vivo conditions they did not demonstrate the same effectiveness. In order to preserve EO inhibitory performances, edible coatings combining polysaccharide matrices (chitosan, arabic gum, and xanthan gum) with EOs were tested. After considering consistency, uniform coverage of the fruit surface, and antifungal properties of the matrix, chitosan was identified as the most suitable component for EO encapsulation. Treatments with chitosan in combination with thyme EO on apple fruits (cv. ‘Braeburn’) showed inhibitory effects on infection caused by B. cinerea (−48% of infected wounds compared to untreated). Similarly, clove EO combined with chitosan reduced the Penicillium infections in apple cv. ‘Golden Delicious’ by 62%. These results therefore suggest the effectiveness of the use of EOs encapsulated with chitosan for the control of postharvest diseases of apple fruits during storage. Full article

The demand for healthy foods without artificial food additives is constantly increasing. Hence, natural food preservation methods using bioprotective cultures could be an alternative to chemical preservatives. Thus, the main purpose of this work was to screen the indigenous lactobacilli isolated from fermented cow milk for their safety and antifungal activity to select the safe strain with the strongest fungicidal properties for the development of bioprotective acid whey protein concentrate (AWPC) based fermentates and their coatings intended for fresh cheese quality maintenance. Therefore, 12 lactobacilli strains were isolated and identified from raw fermented cow milk as protective cultures. The safety of the stains was determined by applying antibiotic susceptibility, haemolytic and enzymatic evaluation. Only one strain, Lacticaseibacillus paracasei A11, met all safety requirements and demonstrated a broad spectrum of antifungal activity in vitro. The strain was cultivated in AWPC for 48 h and grew well (biomass yield 8 log₁₀ cfu mL⁻¹). L. paracasei A11 AWPC fermentate was used as a vehicle for protective culture in the development of pectin-AWPC-based edible coating. Both the fermentate and coating were tested for their antimicrobial properties on fresh acid-curd cheese. Coating with L. paracasei A11 strain reduced yeast and mould counts by 1.0–1.5 log₁₀ cfu mL⁻¹ (p ≤ 0.001) during cheese storage (14 days), simultaneously preserving its flavour and prolonging the shelf life for six days. Full article

Okra has received extensive attention due to its high nutritional value and remarkable functional characteristics, but postharvest diseases have severely limited its application. It is important to further explore the methods and potential methods to control the postharvest diseases of okra. In this study, Colletotrichum fioriniae is the major pathogen that causes okra anthracnose, which can be isolated from naturally decaying okra. The pathogenicity of C. fioriniae against okra was preliminarily verified, and the related biological characteristics were explored. At the same time, an observational study was conducted to investigate the in vitro antifungal effect of thymol edible coating (TKL) on C. fioriniae. After culturing at 28 °C for 5 days, it was found that TKL showed an obvious growth inhibition effect on C. fioriniae. The concentration for 50% of the maximal effect was 95.10 mg/L, and the minimum inhibitory concentration was 1000 mg/L. In addition, it was found that thymol edible coating with a thymol concentration of 100 mg/L (TKL100) may cause different degrees of damage to the cell membrane, cell wall, and metabolism of C. fioriniae, thereby inhibiting the growth of hyphae and causing hyphal rupture. Refer to the results of the in vitro bacteriostatic experiment. Furthermore, the okra was sprayed with TKL100. It was found that the TKL100 coating could significantly inhibit the infection of C. fioriniae to okra, reduce the rate of brown spots and fold on the okra surface, and inhibit mycelium growth. In addition, the contents of total phenols and flavonoids of okra treated with TKL100 were higher than those of the control group. Meanwhile, the activities of phenylalaninammo-nialyase, cinnamic acid-4-hydroxylase, and 4-coumarate-CoA ligase in the lignin synthesis pathway were generally increased, especially after 6 days in a 28 °C incubator. The lignin content of TKL-W was the highest, reaching 65.62 ± 0.68 mg/g, which was 2.24 times of that of CK-W. Therefore, TKL may promote the synthesis of total phenols and flavonoids in okra, then stimulate the activity of key enzymes in the lignin synthesis pathway, and finally regulate the synthesis of lignin in okra. Thus, TKL could have a certain controlling effect on okra anthracnose. Full article

The modern utilization of essential oils such as ginger oil (GO) as an anti-aflatoxin represents a potential target for food preservation and safety; however, the mechanism of action is still unclear. Nanoemulsions, through an edible coating, can enhance the oil’s bioactivity, increase its hydrophilicity, and extend the final product’s shelf-life. In the present study, two edible films for the GO nanoemulsion were prepared by ultrasonication using carboxymethyl cellulose (FB1-GO) and sodium alginate (FB2-GO). The droplet size of FB2-GO was finer (126.54 nm) compared to FB1-GO (289.77 nm). Meanwhile, both had high stability proved by z-potential; +31.54 mV (FB1-GO) and +46.25 mV (FB2-GO) with low PDI values (<0.4). Using gas chromatography-mass spectrometry, the hydrodistilled GO showed 25 compounds, representing 99.17% of the total oil, with α-zingiberene (29.8%), geranial (10.87%), β-bisabolene (8.19%), and ar-curcumene (5.96%) as the predominant. A dramatic increase in α-zingiberene, α-bisabolene and ar-curcumene was due to the homogenization conditions in both FB1-GO and FB2-GO compared to the GO. The FB1-GO exhibited superior antibacterial activity against the examined strains of bacterial pathogens, while FB2-GO was more effective as an antifungal agent on the tested Aspergillus fungi strains. In a simulated liquid media, FB2-GO inhibited the total growth of fungi by 84.87–92.51% and showed the highest reduction in the aflatoxin amount produced. The in silico study presented that, among the GO volatile constituents, sesquiterpenes had the highest binding free energies against the enzymes responsible for aflatoxin production compared to monoterpenes. α-Bisabolene showed the highest affinity toward polyketide synthase (−7.5 Kcal/mol), while ar-curcumene was the most potent against cytochrome P450 monooxygenase (−8.3 Kcal/mol). The above findings clarify the reasons for aflatoxin reduction in simulated media during incubation with FB1-GO and FB2-GO. Full article