Alessandro Bianchi

BACKGROUND: Peppermint ( Mentha piperita L.) essential oil (MPEO) is recognized for its broad‐spectrum antimicrobial properties and potential applications in food preservation. This study aimed to determine whether the bioactivity of MPEO is attributable to ( R )‐(+)‐limonene or whether the complete essential oil provides higher efficacy due to interactions among multiple constituents. RESULTS: MPEO was characterized using GC–MS and evaluated for antimicrobial activity in vitro against Gram‐positive and Gram‐negative bacteria and yeasts, and in situ in the vapor phase on strawberries, plums, beetroot, and tomatoes. Antibiofilm activity against Salmonella enterica was assessed using crystal violet assay and MALDI‐TOF MS, while insecticidal activity was tested against Callosobruchus maculatus and Megabruchidius dorsalis . GC–MS revealed a menthol chemotype dominated by menthol (54.2%), with isomenthone (8.4%), isomenthol acetate (5.7%), 1,8‐cineole (5.7%), linalool (3.1%), β ‐caryophyllene (3.5%), limonene (2.7%), and α ‐pinene (1.5%). MPEO generally produced larger inhibition zones and lower minimum inhibitory concentration values than ( R )‐(+)‐limonene, and stronger in situ growth suppression. Antibiofilm activity was demonstrated in both assays. In insecticidal tests, limonene was more effective than MPEO at 6.25–50%, while both treatments were nearly fully effective at 100%. CONCLUSION: MPEO showed greater overall antimicrobial efficacy than ( R )‐(+)‐limonene, supporting the importance of interactions among its constituents. Its combined antimicrobial, antibiofilm, and insecticidal activities indicate potential for use as a natural bio‐preservative and in integrated pest management. © 2026 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Natural and sustainable solutions for food preservation are increasingly focusing on essential oils as promising agents with potent antimicrobial, antibiofilm, and insecticidal properties. The aim of this study was to evaluate the chemical composition of Osmanthus fragrans essential oil (OFEO), its antimicrobial activity against various Gram-positive and Gram-negative bacteria and yeasts including the biofilm-forming strain Salmonella enterica , its effects on biofilms analyzed by MALDI-TOF MS spectral profiling, and its insecticidal activity against Megabruchidius dorsalis . GC–MS analysis revealed that OFEO predominantly contains trans-β -ionone (24.1%), linalool (18.0%), and 2(3H)-furanone (9.0%), compounds known for their antimicrobial and antibiofilm effects. OFEO exhibited significant antimicrobial activity with minimum inhibitory concentrations (MIC₅₀) ranging from 0.072 to 3.16 mg/mL, while the biofilm-forming Salmonella enterica showed greater tolerance. In situ vapor-phase tests on fresh fruits and vegetables (apple, peach, beetroot, carrot) demonstrated matrix- and concentration-dependent inhibition of microbial growth. MALDI-TOF MS comparison revealed differences in mass spectral profiles of biofilms after OFEO treatment, indicating disruption of biological processes essential for biofilm structure and function. Additionally, OFEO demonstrated potent insecticidal activity against Megabruchidius dorsalis , with 100% mortality observed at full concentration and significant mortality at lower doses. These results support the potential of OFEO as a natural antimicrobial, antibiofilm, and insecticidal agent suitable for improving food safety, extending shelf life, and managing pests in the food industry. Key points: GC-MS identified 27 volatiles defining O. fragrans essential oil composition . O. fragrans oil inhibited pathogens and reduced Salmonella biofilm formation . O. fragrans oil showed strong insecticidal effect on Megabruchidius dorsalis.

Pathogens responsible for foodborne illnesses remain a major public health concern, particularly with the increasing preference for minimally processed and ready‐to‐eat products. Essential oils (EOs) have emerged as promising natural agents for enhancing microbial protection and prolonging shelf life due to their antimicrobial properties. This study investigated the antimicrobial properties of Ocimum basilicum essential oil (OBEO), characterized by a methyl chavicol‐dominant chemotype (88.6%), obtained by steam distillation from fresh flowering plants of Vietnamese origin, as a potential alternative to synthetic preservatives in sous vide processed game meat. The in vitro antimicrobial activity of OBEO against Listeria monocytogenes CCM 4699 was evaluated using disc diffusion and minimum inhibitory concentration methods, yielding an inhibition zone of 16.33 mm and MIC ₅₀ and MIC ₉₀ values of 0.127 and 0.133 mg/mL, respectively. The effectiveness of OBEO was further assessed in sous vide red deer meat inoculated with L. monocytogenes and stored at 4°C for 1 week. OBEO significantly inhibited L. monocytogenes , with enhanced antimicrobial activity observed in vacuum‐sealed treated samples, indicating a synergistic effect with thermal processing. MALDI‐TOF MS analysis identified Pseudomonas corrugata , P. fragi , P. lundensis , P. mucidolens and P. taetrolens as predominant species, with reduced prevalence in OBEO‐treated samples. These findings demonstrate that OBEO can serve as an effective natural antimicrobial agent, improving microbiological safety and extending the shelf life of sous vide game meat.

Background: Anethum graveolens L. (dill) is an economically important aromatic plant cultivated for its seeds and essential oil. Dill straw is commonly treated as an agricultural by-product, despite its potential as an alternative source of essential oil. Water deficit stress and the boron (B) foliar application, represent key factors influencing the plant growth, yield, and essential oil composition. This study aimed to evaluate the effect of the boron application at different rates on the growth, seed yield, straw yield, and the essential oil content and composition of dill under varying irrigation regimes, and to assess the biological activities of the obtained essential oils. Materials and methods: Field experiments were carried out to study the effect of boron (B) fertilization (0, 150 and 300 ppm) on the seed yield, and volatile oil of dill under water deficit stress conditions. The oil was obtained by hydro-distillation extraction method using Clevenger apparatus. Chemical analysis of the oil was done by using gas chromatography and mass spectrometry (GC-MS). The biological activities of the seed essential oil were evaluated. Results: Irrigation at 100% of crop evapotranspiration (ET) combined with 300 ppm B produced the highest seed yield, straw yield, and straw oil yield, while 100- % ET combined with 150 ppm B resulted in the highest seed oil yield. High water use efficiency (WUE) for seed yield and seed oil yield was achieved at 50% ET with 150 ppm B, whereas, the maximum WUE for straw yield and straw oil yield was recorded at 50- % ET with 300 ppm B. GC-MS analysis identified carvone and limonene as the major compounds in dill seed oil, while α-phellandrene and limonene predominated in straw oil. The maximum carvone content in seed oil and α-phellandrene content in straw oil were obtained at 100% ET with 150 ppm B. The Maximum limonene content in both seed and straw oils was recorded under 75- % ET combined with 150 ppm B. The essential oil demonstrated significant antimicrobial, antibiofilm, antioxidant, and insecticidal activities. Conclusions: The Boron foliar application combined with optimized irrigation regimes significantly influenced the yield, water use efficiency, and essential oil composition of A. graveolens . Dill straw represents a valuable and hitherto underutilized source of essential oil with a distinct chemical profile compared to seed oil. The biological activities of both oils support their potential application in food preservation and plant protection. These findings provide a basis for sustainable utilization of dill crop residues and optimization of cultivation practices under water-limited conditions.

The present study investigated the chemical composition, antimicrobial, insecticidal, and food preservation potential of Ligusticum chuanxiong CO₂ oil (LCCO) standardised to a ligustilide content of ≥35%. The volatile composition of LCCO was characterised by GC-MS and found to be dominated by cis-ligustilide (63.3%), senkyunolide (15.8%), 3-butylidenephthalide (5.4%), and trans-neocnidilide (4.9%). In vitro antimicrobial activity was evaluated by disc diffusion and broth microdilution against six bacterial and five yeast reference strains. The largest inhibition zones were observed against Enterococcus faecalis (14.33 mm) and Staphylococcus aureus (13.67 mm). MIC₅₀ values ranged from 0.064 mg/mL (Yersinia enterocolitica) to 3.492 mg/mL (Candida tropicalis), while MIC₉₀ values ranged from 0.151 to 3.800 mg/mL. In situ vapour-phase antimicrobial activity was evaluated on pear, banana, white radish, and carrot at concentrations of 62.5–500 µL/L, demonstrating a clear concentration-dependent inhibitory effect across all tested food matrices and microorganisms. Insecticidal activity against Callosobruchus maculatus and Megabruchidius dorsalis was confirmed under fumigation conditions, with LC₅₀ values of 17.50% and 20.99% and LC90 values of 83.10% and 87.60%, respectively. The effect of LCCO, applied alone and in combination with vacuum packaging, on the microbiological quality of fresh white radish was evaluated over 28 days of refrigerated storage at 4 °C. The combined treatment resulted in the lowest total viable count (2.75 log CFU/g) and coliform bacteria count (2.58 log CFU/g) on day 28. A total of 404 bacterial isolates were identified using MALDI-TOF MS Biotyper, comprising 22 species. Acinetobacter pittii was the predominant species (33%), followed by Pantoea agglomerans (7%) and Serratia nematodiphila (7%). No Pseudomonas species were recovered from the EO vacuum treatment. Overall, these findings demonstrate the potential of LCCO, particularly in combination with vacuum packaging, as a natural antimicrobial agent for the postharvest preservation of fresh white radish.