The production of clove essential oil by hydro distillation and steam distillation has been experimentally investigated. The density of the oil was determined to be ρ ≈ 1.0648 g cm-3. By means of hydro-distillation, a higher yield of 9.714 mass % was obtained compared to the steam distillation - 4.986 mass %. This is due to the formation of a hard-to-break emulsion in the distillate when using the steam distillation technique. Liquid-liquid extraction and gravity sedimentation were independently applied for the aim of separating the essential oil from the obtained distillate. The obtained yield of clove oil per distillate unit using liquid-liquid extraction was 9.714 mass % and its higher than that found by gravity sedimentation - 4.95 mass % using the same production method. However, considering the final cost per unit of produced oil and its intended use in foods, cosmetics and medicines, separation of the oil by gravity settling is more suitable.

This study explored the batch membrane filtration of 40% ethanol extracts from spent lavender, containing valuable compounds like rosmarinic acid, caffeic acid, and luteolin, using a polyamide-urea thin film composite X201 membrane. Conducted at room temperature and 20 bar transmembrane pressure, the process demonstrated high efficiency, with rejection rates exceeding 98% for global antioxidant activity and 93–100% for absolute concentrations of the target components. During concentration, the permeate flux declined from 2.43 to 1.24 L·m⁻²·h⁻¹ as the permeate-to-retentate-volume ratio increased from 0 to 1. The process resistance, driven by osmotic pressure and concentration polarization, followed a power–law relationship with a power value of 1.20, consistent with prior nanofiltration studies of rosmarinic acid solutions. Notably, no membrane fouling occurred, confirming the method’s scalability without compromising biological activity. The antioxidant activity, assessed via the DPPH method, revealed that the retentate exhibited double the activity of the feed. Antibacterial assays using broth microdilution showed that the retentate inhibited Escherichia coli by 73–96% and Bacillus subtilis by 97–98%, making it the most active fraction. These findings validate the effectiveness of the X201 membrane for concentrating natural antioxidants and antibacterial agents from lavender extract under sustainable operating conditions.

The essential oil produced from R. damascena petals is one of the most valuable and important base materials in the flavour and fragrance industry. For each ton of processed rose flowers, less than 0.5 kg of essential oil and about 4 tons of residual water is generated. Due to the presence of polyphenolic compounds in the latter, its uncontrolled disposal has an adverse effect on the ecological balance. Moreover, valuable substances with biological activity are lost. The possibility to recover by nanofiltration a refined polyphenolic fraction, composed primarily of flavonoids, their glycosides and polyphenolic acids, contained in the waste residual water was demonstrated in the present work. The nanofiltrations were carried out with DL (Veolia) and NP030 (Mycrodin Nadir) commercial nanofiltration membranes. The DL membrane was proposed for process design due to its lower susceptibility to fouling by the target solutes. The experimentally determined membrane permeance for the DL membrane ranged from 1.8 to 0.5 LMH bar-1 during batch concentration at an operating pressure of 10 bar and degree of feed volume reduction in the range from 1 to 2. Since the target compounds are well known antioxidants, their concentrations in the studied materials were evaluated in terms of global antioxidant activity. The retentates were up to 2.00 times more potent antioxidants compared to the feed solutions. The experimentally determined membrane rejection coefficients for both membranes with respect to global antioxidant activity were in agreement with theoretically predicted values reported in a previous study, indicating efficient membrane fractionation.

Recently, essential rose oils and rose products have gained increasing importance in both the cosmetic and food industries, as well as in the composition of medicinal products. We investigated the in vitro antiviral activity of essential oil and floral water from Rosa damascena Mill against herpes simplex virus type 1 (HSV-1) infection in rabbit retinal cells (RRCs). The composition of the main chemical components in the rose essential oil was determined by means of gas chromatographic analysis. The effect on the viral replication cycle was determined using the cytopathic effect (CPE) inhibition assay. The virucidal activity, the effect on the adsorption stage of the virus to the host cell, and the protective effect on healthy cells were evaluated using the endpoint dilution method. The effects were determined as deviation in the viral titer, Δlg, for the treated cells from the one for the untreated viral control. The identified main active components of rose oil are geraniol (28.73%), citronellol (21.50%), nonadecane (13.13%), nerol (5.51%), heneicosane (4.87%), nonadecene (3.93), heptadecane (2.29), farnesol (2.11%), tricosane (1.29%), eicosane (1.01%), and eugenol (0.85%). The results demonstrated that both rose products do not have a significant effect on the virus replication but directly affect the viral particles and reduce the viral titer by Δlg = 3.25 for floral water and by Δlg = 3.0 for essential oil. Significant inhibition of the viral adsorption stage was also observed, leading to a decrease in the viral titers by Δlg = 2.25 for floral water and by Δlg = 2.0 for essential oil. When pretreating healthy cells with rose products, both samples significantly protected them from subsequent infection with HSV-1. This protective effect was more pronounced for the oil (Δlg = 2.5) compared to the one for the floral water (Δlg = 2.0). We used the in silico molecular docking method to gain insight into the mechanism of hindrance of viral adsorption by the main rose oil compounds (geraniol, citronellol, nerol). These components targeted the HSV-1 gD interaction surface with nectin-1 and HVEM (Herpesvirus Entry Mediator) host cell receptors, at N-, C-ends, and N-end, respectively. These findings could provide a structural framework for further development of anti-HSV-1 therapeutics.

An approach of great certainty is suggested as to avoid concentration unsteadiness with a CVD delivery system employing bubbler. Assuming that the carrier gas has to be saturated of precursor vapour during the entire CVD experiment a set of equations has been selected from the literature for calculating the height of liquid layer in the bubbler which is necessary to this aim. The selection is made on the prerequisites that gas bubbles are spherical, diffusion of precursor vapour in them is molecular and it takes place during their rising only, which has a velocity equal to the terminal bubble velocity of rising. The errors at levels lower than the one for saturation are discussed. Heights of Al(CH₃)₃ calculated using the approach are compared to those at which the bubbler controlling LED indicator of Dow Electronic Materials lights green, amber or red.

The present study explores the possibility of combining membrane concentration, spray drying, and low-temperature precipitation into a single process for the valorization of spent lavender biomass as a source of ingredients rich in antioxidants. Lavender spent plant material was subjected to solid–liquid extraction, and the obtained hydroalcoholic extracts were further concentrated using a dead-end membrane filtration cell (METcell) with a polyamide–urea thin-film composite X201 membrane. The feed and the obtained retentate were subsequently spray dried using a Nano Spray Dryer B-90 (BÜCHI) under different temperature conditions (120 °C and 85 °C). Low-temperature precipitation was further applied for the retentate. An eight-fold concentration of the extracts was achieved, with membrane rejection coefficients of 100% for antioxidant activity and 98.5% for dry solids content. The permeate flux ranged from 2.25 to 0.201 L·m⁻²·h⁻¹. Spray drying at a lower inlet temperature resulted in minimal losses for antioxidant activity (below 6%). The low-temperature storage of the membrane concentrate led to clear phase separation, allowing for the recovery of a precipitated fraction. The obtained results demonstrate that the integrated approach may support the sustainable and scalable valorization of lavender by-products.