Non-thermal plasma (NTP) treatment of Trigonella foenum-graecum L. seeds stimulates the sprout growth and the production of nutraceutical compounds.

The possibility to stimulate the production of some nutraceutical properties of fenugreek (Trigonella foenum-graecum L.) sprouts by non-thermal plasma (NTP) processing of the seeds in different conditions was studied. The non-thermal plasma used in this work was a surface dielectric barrier discharge. Two types of processing were performed: direct NTP treatment and NTP with a cover treatment, to simulate the processing of packaged seeds. For all treatments, the effect of pre-soaking of the seeds was studied as well. The analyses of the seeds after processing indicated an increase of the hydrophilicity of their surface for NTP direct treatment as resulted from the water contact angle measurements, which could be due to the strong etching evidenced by scanning electron microscopy imaging. A significant (p < 0.05) increase of the seedling growth, by up to 50%, was found especially for the pre-soaked seeds. These results were correlated with the increase of chlorophyll pigments concentrations, with higher concentrations in the case of NTP direct treatment than for the NTP with cover treatments. Direct NTP treatment for 30 s of dry seeds led to the highest increase of the flavonoid concentration of about three times compared to that obtained for untreated seeds. For the polyphenols and antioxidant activity, NTP with cover treatments proved to be better, with a significant increase, especially for 90 s treatment of the pre-soaked seeds. All the results indicate the possibility of tuning the nutraceutical properties of fenugreek sprouts by NTP treatment.

Nano-Biocomposite Materials Obtained from Laser Ablation of Hemp Stalks for Medical Applications and Potential Component in New Solar Cells.

The study in this paper presents a new material that was produced as a thin film by the Pulsed Laser Deposition technique (PLD) using a 532 nm wavelength and 150 mJ/pulse laser beam on the hemp stalk as target. The analyses performed by spectroscopic techniques (Fourier Transform Infrared Spectroscopy-FTIR, Laser-Induced Fluorescence Spectroscopy-LIF, Scanning Electron Microscopy coupled with Energy Dispersive X-ray-SEM-EDX, Atomic Force Microscopy-AFM and optical microscope) evidenced that a biocomposite consisting of lignin, cellulose, hemicellulose, waxes, sugars and phenolyc acids p-coumaric and ferulic, similar to the hemp stalk target was obtained. Nanostructures and aggregated nanostructures of 100 nm to 1.5 µm size were evidenced. Good mechanical strength and its adherence to the substrate were also noticed. It was noticed that the content in calcium and magnesium increased compared to that of the target from 1.5% to 2.2% and from 0.2% to 1.2%, respectively. The COMSOL numerical simulation provided information on the thermal conditions that explain phenomena and processes during laser ablation such as C-C pyrolisis and enhanced deposition of calcium in the lignin polymer matrix. The good gas and water sorption properties due to the free OH groups and to the microporous structure of the new biocomposite components recommends it for studies for functional applications in medicine for drug delivery devices, filters in dialysis and for gas and liquid sensors. Functional applications in solar cells windows are also possible due to the conjugated structures of the contained polymers.

Prenylated phenolics as promising candidates for combination antibacterial therapy: Morusin and kuwanon G.

Combination of antibiotics with natural products is a promising strategy for potentiating antibiotic activity and overcoming antibiotic resistance. The purpose of the present study was to investigate whether morusin and kuwanon G, prenylated phenolics in Morus species, have the ability to enhance antibiotic activity and reverse antibiotic resistance in Staphylococcus aureus and Staphylococcus epidermidis. Commonly used antibiotics (oxacillin, erythromycin, gentamicin, ciprofloxacin, tetracycline, clindamycin) were selected for the combination studies. Checkerboard and time-kill assays were used to investigate potential bacteriostatic and bactericidal synergistic interactions, respectively between morusin or kuwanon G and antibiotics. According to both fractional inhibitory concentration index and response surface models, twenty combinations (14 morusin-antibiotic combinations, six kuwanon G-antibiotic combinations) displaying bacteriostatic synergy were identified, with 4-512-fold reduction in the minimum inhibitory concentration values of antibiotics in combination. Both morusin and kuwanon G reversed oxacillin resistance of methicillin-resistant Staphylococcus aureus. In addition, morusin reversed tetracycline resistance of Staphylococcus epidermidis. At half of the minimum inhibitory concentrations, combinations of morusin with oxacillin or gentamicin showed bactericidal synergy against methicillin-resistant Staphylococcus aureus. Fluorescence and differential interference contrast microscopy and scanning electron microscopy showed an increase in the membrane permeability and massive leakage of cellular content in methicillin-resistant Staphylococcus aureus exposed to morusin or kuwanon G. Overall, our findings strongly indicate that both prenylated compounds are good candidates for the development of novel antibacterial combination therapies.

Tailoring the Surface Functionalities of Radio Frequency Magnetron-Sputtered ZnO Thin Films by Ar/NH3 Gas Mixture Surface-Wave Plasmas.

The surface functionalization of radio frequency magnetron-sputtered zinc oxide (ZnO) thin films tailored by low-pressure Ar/NH3 mixture surface-wave plasmas (SWPs) is discussed based on the results of photoluminescence (PL), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and spectrophotometric measurements. At an Ar/NH3 gas mixture ratio of 70%/30%, both the PL intensity of the near-band-edge emission and the XRD intensity of the ZnO(002) reflection peak were enhanced by about 5.5 and 8 times, respectively, compared to the values for the as-grown sample. Furthermore, the XPS and spectrophotometric analyses using the fluorescent dye showed that the amine group functionalization over the surface of the ZnO films reached their maximum values at the same gas ratio. From the results of optical emission spectroscopic and ion mass spectrometric measurements in the Ar/NH3 mixture SWPs, it is inferred that the nitrogen-containing reactive species, such as NH x+ ( x = 1-4) ions and NH y ( y = 1, 2) molecules in addition to H radicals might crucially interact with the defective ZnO surface lattices to repair the ZnO thin films from compressive to strain-free crystallized structures, enhance the PL intensity, and produce the amine group surface functionalization.

Application of Pomace Powder of Black Carrot as a Natural Food Ingredient in Yoghurt.

Researchers and food manufacturers are investigating the use of fruit and vegetable by-products as nutrient-dense food ingredients in response to increasing consumer requests for healthier and more natural foods. Black carrot (Daucus carota L.), a root vegetable variety of deep purple carrot, is a valuable source of nutrients with excellent health benefits and nutraceutical effects. Black carrot pomace (BCP), a by-product of industrial juice extraction, is abundant in bioactive compounds, dietary fiber, antioxidants, and pigments such as anthocyanins. Value addition and sustainability are perspectives provided by using this underutilized agricultural by-product in food applications. With an emphasis on BCP powder's effects on phytochemical and physicochemical qualities, mineral and color characteristics, and sensory aspects, this study aims to assess the effects of adding BCP powder to yogurt formulations. The findings show that the addition of BCP powder improved the nutritional, and the color of the yogurts, providing a visually appealing product. Moreover, adding the BCP powder raised the amount of phytochemicals and the antioxidant activity in the final product's formulation. The manufacturing of such products can not only aid in promoting sustainable food production but also offer consumers a wider range of innovative food options with improved properties.

Non-Thermal Plasma (NTP) Treatment of Alfalfa Seeds in Different Voltage Conditions Leads to Both Positive and Inhibitory Outcomes Related to Sprout Growth and Nutraceutical Properties.

Non-thermal plasma (NTP) has proven to be a green method in the agricultural field for the stimulation of germination, growth, and production of nutraceutical compounds in some cases. However, the process is far from being fully understood and depends on the targeted plant species and the NTP used. In this work, we focus on the production of alfalfa sprouts from NTP-treated seeds under different voltage conditions. A flexible electrode configuration was used to produce the NTP, which can also be placed on packages for in-package treatments. The surface of the seeds was analyzed, indicating that the microstructure was strongly affected by NTP treatment. Biometric measurements evidenced the possibility of stimulating the sprout growth in some conditions by up to 50% compared to the sprouts obtained from untreated seeds. Biochemical traits for the sprouts obtained in different processing conditions were also studied, such as the concentrations of chlorophyll pigments, flavonoids and polyphenols, and antioxidant activity. Most NTP treatments led to inhibitory effects, proving the strong dependence between NTP treatment and targeted plant species.

Red Onion Peel Powder as a Functional Ingredient for Manufacturing Ricotta Cheese.

Onion (Allium cepa L.) is a vegetable widely cultivated and consumed due to its rich content in bioactive compounds. Red onion peel (ROP) powder, which is a by-product derived from the onion industry, has been attracting significant interest as a potential functional ingredient for improving the overall quality of foods. The present study explores the potential of ROP powder as a functional ingredient to improve the quality and nutritional value of whey cheese. Despite being frequently viewed as a food processing waste byproduct, ROP is a rich source of bioactive substances, including antioxidants, flavonoids, and dietary fiber, having antioxidant and antibacterial effects. The ROP extract exhibited high amounts of total polyphenols (119.69 ± 2.71 mg GAE/g dw) and antioxidant activity (82.35 ± 1.05%). Different quantities (1 and 3%) of ROP powder were added to cheese formulations, and the subsequent impact on the texture characteristics, sensory attributes, and phytochemical composition of the value-added cheeses was evaluated. The findings show that the addition of ROP powder improved the texture and the color of the cheeses, providing a visually appealing product. Additionally, adding the ROP powder significantly raised the amount of phytochemicals and antioxidant activity (17.08 ± 0.78 µmol TE/g dw for RCROP1, 24.55 ± 0.67 µmol TE/g dw for RCROP2) in the final product's formulation. Moreover, adding powder to cheese is an effective way to increase the value of onion by-products and produce polyphenol-enriched cheese.

Salinity Stress Influences the Main Biochemical Parameters of Nepeta racemosa Lam.

In this work, the effects of salt stress on Nepeta racemosa Lam. were studied to analyze the possibility of using it as a potential culture for salinity-affected soils. A total of nine concentrations of salts-NaCl (18, 39, and 60 mg/100 g soil), Na2SO4 (50, 85, and 120 mg/100 g soil), and a mixture (9 g NaCl + 25 g Na2SO4, 19 g NaCl + 43 g Na2SO4, and 30 g NaCl + 60 g Na2SO4/100 g soil)-simulated real salinity conditions. Environmental electron microscopy offered information about the size and distribution of glandular trichomes, which are very important structures that contain bioactive compounds. The chlorophyll pigments, polyphenols, flavonoids, and antioxidant activity were determined based on spectrophotometric protocols. The results have shown a different impact of salinity depending on the salt type, with an increase in bioactive compound concentrations in some cases. The highest polyphenol concentrations were obtained for Na2SO4 variants (47.05 and 46.48 mg GA/g dw for the highest salt concentration in the first and second year, respectively), while the highest flavonoid content was found for the salt mixtures (42.77 and 39.89 mg QE/g dw for the highest concentrations of salt in the first and, respectively, the second year), approximately 100% higher than control. From the Pearson analysis, strong correlations were found between chlorophyll pigments (up to 0.93), antioxidant activity and yield for the first harvest (up to 0.38), and antioxidant activity and flavonoid content for the second harvest (up to 0.95). The results indicate the possibility of growing the studied plants in salt-stress soils, obtaining higher concentrations of bioactive compounds.

Optical and Structural Analysis of TiO2-SiO2 Nanocomposite Thin Films Fabricated via Pulsed Laser Deposition Technique.

TiO2-SiO2 nanocomposite thin films have gained the attention of the scientific community due to their unique physical and chemical properties. In this paper, we report on the fabrication and characterization of a TiO2-SiO2 nanocomposite disk-shaped target. The target was used for the deposition of TiO2-SiO2 nanocomposite thin films on fluorine-doped tin oxide/glass substrates using the pulsed laser deposition (PLD) technique. The thicknesses of the thin films were fixed to 100 nm, and the deposition temperature ranged from room temperature to 300 °C. As revealed by the microstructural and morphological characterizations revealed, the TiO2-SiO2 nanocomposite thin films are amorphous and display homogeneous distribution. The determined values of the indirect optical band gap range from 2.92 to 3.07 eV, while those of the direct optical band gap lie between 3.50 and 3.55 eV. Additionally, as the deposition temperature decreases, the light transmission increases in the visible and in the ultraviolet ranges, which is suitable for flexible perovskite solar cells. This research can uncover new insights into the fabrication of amorphous TiO2-SiO2-based nanostructured thin films using the PLD technique for perovskite solar cell technology.

Dual-Pulsed Laser Ablation of Oyster Shell Producing Novel Thin Layers Deposed to Saccharomyces cerevisiae.

Dual-pulsed (DPL) laser deposition using oyster shells as targets was studied in order to find out if this method can replace the use of high-power pulsed lasers. Aspects related to changes in the morphological structure of the thin layer but also to the chemical composition of the obtained thin layer were analyzed and compared with the target as well as with the thin layers obtained with a higher power pulsed laser in a single-pulsed (SPL) regime. Orthorhombic structures were noticed with Scanning Electron Microscopy for the thin film obtained in DPL mode compared to the irregular particles obtained in SPL mode. The deacetylation process during ablation was evidenced by Fourier Transform Infrared spectroscopy, resulting in chitosan-based thin films. The effect of the obtained thin films of chitosan on the cells of baker's yeast (Saccharomyces cerevisiae) was studied. Restoration of the yeast paste into initial yeast was noticed mainly when the hemp fabric was used as support for the coating with yeas which was after that coated with chitosan thin film produced by DPL method.

Evaluation of the Antibacterial Properties of Polyvinyl Alcohol-Pullulan Scaffolds Loaded with Nepeta racemosa Lam. Essential Oil and Perspectives for Possible Applications.

Essential oil of Nepeta racemosa Lam. was extracted and characterized to determine its antimicrobial activity and potential use in applications. The essential oil was loaded on polyvinyl alcohol-pullulan films and gels and characterized by optical microscopy, scanning electron microscopy, and UV-Vis spectroscopy before having its antimicrobial capacities assessed. The essential oil extracted from Nepeta racemosa Lam. was characterized using gas chromatography coupled with mass spectroscopy, which indicated that the most abundant component was nepetalic acid (55.5%), followed by eucalyptol (10.7%) and other compounds with concentrations of about 5% or less. The essential oil, as well as the loaded films and gels, exhibited good antibacterial activity on both gram-positive and gram-negative strains, with growth inhibition zones larger in some cases than for gentamicin, indicating excellent premises for using these essential-oil-loaded materials for applications in the food industry or biomedicine.

Antimicrobial Activity of Artemisia dracunculus Oil-Loaded Agarose/Poly(Vinyl Alcohol) Hydrogel for Bio-Applications.

In this study, the potential use of Artemisia dracunculus essential oil in bio-applications was investigated. Firstly, the phytochemicals from Artemisia dracunculus were analyzed by different methods. Secondly, the Artemisia dracunculus essential oil was incorporated into the hydrogel matrix based on poly(vinyl alcohol) (PVA) and agar (A). The structural, morphological, and physical properties of the hydrogel matrix loaded with different amounts of Artemisia dracunculus essential oil were thoroughly investigated. FTIR analysis revealed the successful loading of the essential oil Artemisia dracunculus into the PVA/A hydrogel matrix. The influence of the mechanical properties and antimicrobial activity of the PVA/A hydrogel matrix loaded with different amounts of Artemisia dracunculus was also assessed. The antimicrobial activity of Artemisia dracunculus (EO Artemisia dracunculus) essential oil was tested using the disk diffusion method and the time-kill assay method after entrapment in the PVA/A hydrogel matrices. The results showed that PVA/agar-based hydrogels loaded with EO Artemisia dracunculus exhibited significant antimicrobial activity (log reduction ratio in the range of 85.5111-100%) against nine pathogenic isolates, both Gram-positive (S. aureus, MRSA, E. faecalis, L. monocytogenes) and Gram-negative (E. coli, K. pneumoniae, S. enteritidis, S. typhimurium, and A. salmonicida). The resulted biocompatible polymers proved to have enhanced properties when functionalized with the essential oil of Artemisia dracunculus, offering opportunities and possibilities for novel applications.

The Antibacterial Synthetic Flavonoid BrCl-Flav Exhibits Important Anti-Candida Activity by Damaging Cell Membrane Integrity.

Infections caused by Candida are very difficult to treat due to increasing antifungal resistance. Recent studies showed that patients with Candida infections resistant to fluconazole have very few treatment options. Therefore, finding new efficient antifungal agents is a matter of medical high priority. The aim of this study was to explore the antifungal potential of BrCl-flav-a representative of a new class of synthetic flavonoids with bromine as halogen substituent at the benzopyran core against four Candida clinical strains. Determination of minimum inhibitory concentration and minimum fungicidal concentration along with the time kill assay indicated a strong antifungal effect of BrCl-flav against C. albicans, C. parapsilosis, C. krusei and C. glabrata. The investigation of anti-Candida mechanism of action using fluorescence microscopy and scanning electron microscopy revealed that Br-Cl flav could inhibit fungal growth by impairing the membrane integrity, the resulting structural damages leading to cell lysis. BrCl-flav also showed important anti-virulence properties against Candida spp., inhibiting biofilm formation and yeast to hyphal transition. A strong synergistic antifungal effect against C. albicans strain was observed when BrCl-flav was used in combination with fluconazole. BrCl-flav has a good potential to develop new effective antifungal agents in the context of Candida spp. multidrug resistance phenomenon.

Nanocapillary Atmospheric Pressure Plasma Jet: A Tool for Ultrafine Maskless Surface Modification at Atmospheric Pressure.

With respect to microsized surface functionalization techniques we proposed the use of a maskless, versatile, simple tool, represented by a nano- or microcapillary atmospheric pressure plasma jet for producing microsized controlled etching, chemical vapor deposition, and chemical modification patterns on polymeric surfaces. In this work we show the possibility of size-controlled surface amination, and we discuss it as a function of different processing parameters. Moreover, we prove the successful connection of labeled sugar chains on the functionalized microscale patterns, indicating the possibility to use ultrafine capillary atmospheric pressure plasma jets as versatile tools for biosensing, tissue engineering, and related biomedical applications.