Giuseppina Mandalari

Wound healing is a complex biological process involving overlapping phases of hemostasis, inflammation, proliferation, and remodeling, coordinated by a network of cytokines, growth factors, and cellular responses. Natural products, particularly plant oils, are increasingly being studied for their antioxidant, anti-inflammatory, and regenerative properties. Specifically, this study evaluated the healing potential of almond oil through topical application in an excisional wound model induced in mice, treated once daily for 7 days. Histological, biochemical, and molecular analyses demonstrated that topical treatment with almond oil accelerates wound healing, collagen deposition, and re-epithelialization, and stimulates angiogenesis. At the molecular level, almond oil reduced the expression of MMP-9, increased TGF-β and VEGF, and activated the Nrf2/HO-1 antioxidant pathway, helping limit oxidative and nitrosative stress. Furthermore, it inhibited NF-κB activation and reduced levels of pro-inflammatory cytokines (IL-1β, TNF-α, IL-6). These results indicate that almond oil promotes skin healing through synergistic anti-inflammatory, antioxidant, and regenerative actions, supporting its use as a natural and sustainable topical agent for wound management in clinical settings.

Melanins are pigments widely distributed in microbial, plant, and animal kingdoms. Their UV–visible light shielding capacity, metal chelation ability, antioxidant, and antimicrobial properties make these pigments suitable for different industrial applications like in cosmetic and bioremediation fields. The actual manufacturing process relies on the extraction from animal tissues like the ink of Sepia officinalis and/or on synthetic chemical procedures. Streptomycetes might be the ideal candidates for the development of biotechnological processes of melanin production due to their ability to produce pigments as secondary metabolites, extracellularly released. Here, a new strain of Streptomyces nigra, capable of efficiently producing eumelanin, was isolated from soil samples in Messina, Sicily, Italy, and characterized first by 16S rRNA analysis and then by whole genome sequencing, with a complete gene clusters analysis. The strain ability of growing and producing melanin was tested on four media, including newly formulated ones, and by also optimizing temperature and pH conditions of growth, a melanin production of 2.45 ± 0.01 g/L was reached. The pigment, once produced under the optimal conditions, was purified and characterized by UV–visible, FT-IR, NMR, and EPR spectroscopy, revealing an eumelanin-like structure. Key points: • A new Streptomyces nigra strain, MT6, was isolated and identified • A new formulated medium boosted melanin production up to 2.45 g/L • The extracellular pigment was characterized as eumelanin

Candidiasis arises from the proliferation of Candida species in the human body, especially in individuals with compromised immune systems. Efficient therapeutic management of candidiasis is often hampered by the limited availability of potent antifungal drugs and the emergence of drug-resistant strains. We have previously identified the N-[(4-sulfamoylphenyl)methyl][1,1′-biphenyl]-4-carboxamide to have fungistatic and fungicidal properties, likely due to the hydrophobic biphenyl–chemical features affecting the structural organization of Candida spp. cell membrane. Here, we designed and synthesized a novel series of twelve 5-arylfuran-2-carboxamide derivatives bearing a new hydrophobic tail as bioisosteric replacement of the diphenyl fragment. Its antifungal effectiveness against C. albicans, C. glabrata, and C. parapsilosis, including ATCC and clinically isolated strains, was assessed for all compounds. The most active compound was N-benzyl-5-(3,4-dichlorophenyl)furan-2-carboxamide (6), with fungistatic and fungicidal effects against C. glabrata and C. parapsilosis strains (MIC = 0.062–0.125 and 0.125–0.250 mg/mL, respectively). No synergistic effects were observed when combined with fluconazole. Interestingly, fluorescent microscopy analysis after staining with SYTO 9 and propidium iodide revealed that compound 6 affected the cell membrane integrity in C. albicans strain 16. Finally, carboxamide 6 exhibited a dose-dependent cytotoxicity on erythrocytes, based on assessing the LDH release.

Background: Post-harvest storage of natural almonds is a critical step, as it can cause the onset of microbial contamination and modify polyphenolic composition of almond skin, potentially altering the antioxidant capacity and overall, the health effects of the native product. This study aims to evaluate the impact of different post-harvest storage conditions on the microbiological stability, polyphenolic profile, and antioxidant activity of natural almonds (Prunus dulcis cv. “Fascionello”).Methods: Natural almonds were obtained from Consorzio Mandorla di Avola and stored under three conditions: light exposure at room temperature (RT), dark at RT, and dark at 4°C, monitoring temperature and relative humidity. Samples were analyzed at four time points (T₀, T₃, T₆, and T₉ months). Microbiological stability was assessed using standard plate-counting techniques; polyphenolic content was determined through spectrophotometric assays and RP-LC-DAD-ESI-MS/MS analysis, whereas the antioxidant activity was evaluated using different spectrophotometric and spectrofluorimetric assays including DPPH, TEAC, FRAP, and ORAC assays. Chemometric analyses were performed to compare polyphenolic changes across different storage conditions over time.Results: Temperature remained stable with moderate variations, indicating a well-controlled environment, while humidity exhibits significant fluctuations, likely influenced by external factors. No significant microbial contamination was detected throughout storage, confirming the microbiological safety of natural almonds. The polyphenolic content significantly decreased within the first 3 months, particularly under dark conditions at RT. However, a recovery phase was observed at 6 months, with cold-stored almonds retaining the highest levels of total polyphenols and flavonoids. The antioxidant activity of almond skin extracts correlated with polyphenolic content, showing an initial decline followed by stabilization under refrigerated storage. Hierarchical clustering analyses highlighted distinct polyphenolic expression patterns based on storage conditions and time points.Conclusion: Post-harvest storage conditions significantly impact the polyphenolic profile and antioxidant properties of natural almonds. For short-term storage (≤6 months), RT with controlled light exposure is sufficient to preserve polyphenols, whereas cold and dark conditions are recommended to maintain bioactive compound stability and antioxidant potential for long-term storage (>6 months). These findings provide valuable insights for optimizing storage strategies in the food, nutraceutical, and pharmaceutical industries.

Since the onset of the COVID-19 (COronaVIrus Disease 19) pandemic, SARS-CoV-2 has exhibited a high transmission rate, further enhanced by new variants able to better adapt to humans. Addressing this issue has been challenging due to viral resistance and side effects associated with antiviral drugs and vaccines. As a result, there has been a growing interest in plant-derived compounds with antiviral properties. Our study revealed that pistachio extracts significantly inhibited SARS-CoV-2 viral entry. Employing pseudotyped particles bearing the S protein of SARS-CoV-2, we demonstrated that treatment with pistachio extracts inhibited binding of alpha (α) and omicron (ο) SARS-CoV-2 variants. Furthermore, our study revealed that the pistachio carotenoid zeaxanthin exhibited a different inhibitory activity against two SARS-CoV-2 variants. In silico analyses demonstrated a strong interaction between zeaxanthin and the receptor-binding domain (RBD) domain of the omicron spike (S) protein, thus reducing pseudovirus entry. However, zeaxanthin’s weaker interaction with the alpha variant’s RBD was insufficient to inhibit entry. Additionally, zeaxanthin suppressed the expression of the host protease TMPRSS2 at the protein level, thereby limiting the internalization of the alpha variant, which relies on TMPRSS2 for cellular entry.

Over the last ten years, researchers’ efforts have aimed to replace the classic linear economy model with the circular economy model, favoring green chemical and industrial processes. From this point of view, biologically active molecules, coming from plants, flowers and biomass, are gaining considerable value. In this study, firstly we focus on the development of a green protocol to obtain the purification of anthocyanins from the flower of Callistemon citrinus, based on simulation and on response surface optimization methodology. After that, we utilize them to manufacture and add new properties to bioplastics belonging to class 3, based on modified polyvinyl alcohol (PVA) with increasing amounts from 0.10 to 1.00%. The new polymers are analyzed to monitor morphological changes, optical properties, mechanical properties and antioxidant and antimicrobial activities. Fourier transform infrared spectroscopy (FTIR) spectra of the new materials show the characteristic bands of the PVA alone and a modification of the band at around 1138 cm⁻¹ and 1083 cm⁻¹, showing an influence of the anthocyanins’ addition on the sequence with crystalline and amorphous structures of the starting materials, as also shown by the results of the mechanical tests. These last showed an increase in thickening (from 29.92 μm to approx. 37 μm) and hydrophobicity with the concomitant increase in the added anthocyanins (change in wettability with water from 14° to 31°), decreasing the poor water/moisture resistance of PVA that decreases its strength and limits its application in food packaging, which makes the new materials ideal candidates for biodegradable packaging to extend the shelf-life of food. The functionalization also determines an increase in the opacity, from 2.46 to 3.42 T%/mm, the acquisition of antioxidant activity against 2,2-diphenyl-1-picrylhdrazyl and 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radicals and, in the ferric reducing power assay, the antimicrobial (bactericidal) activity against different Staphylococcus aureus strains at the maximum tested concentration (1.00% of anthocyanins). On the whole, functionalization with anthocyanins results in the acquisition of new properties, making it suitable for food packaging purposes, as highlighted by a food fresh-keeping test.

Increased global research is focused on the development of novel therapeutics to combat antimicrobial and antiviral resistance. Pistachio nuts represent a good source of protein, fiber, monounsaturated fatty acids, minerals, vitamins, and phytochemicals (carotenoids, phenolic acids, flavonoids and anthocyanins). The phytochemicals found in pistachios are structurally diverse compounds with antimicrobial and antiviral potential, demonstrated as individual compounds, extracts and complexed into nanoparticles. Synergistic effects have also been reported in combination with existing drugs. Here we report an overview of the antimicrobial and antiviral potential of pistachio nuts: studies show that Gram-positive bacterial strains, such as Staphylococcus aureus, are the most susceptible amongst bacteria, whereas antiviral effect has been reported against herpes simplex virus 1 (HSV-1). Amongst the known pistachio compounds, zeaxanthin has been shown to affect both HSV-1 attachment penetration of human cells and viral DNA synthesis. These data suggest that pistachio extracts and derivatives could be used for the topical treatment of S. aureus skin infections and ocular herpes infections.

The use of whole-cell biocatalysts in microbial cell factories is of great interest to produce added-value compounds. Through large-scale fermentative processes, which use secondary raw materials as substrates, it is possible to recycle and upgrade agro-industrial by-products. This review addresses the main fermentative processes and bioreactors currently used for the valorization of orange peel, a by-product of the Citrus processing industry. Among the main added-value products, bioethanol, organic acids, enzymes, single cell proteins (SCPs), dyes and aromatic compounds have been industrially produced using orange peel via solid state fermentation and submerged fermentation. This approach fits within the circular economy goals in terms of clean technology and renewable energy, valorization and recycling, upgrade of industrial by-products and sustainability.