α-Pinene is the bicyclic, unsaturated terpene hydrocarbon present in many plants. Due to its beneficial chemical properties, this compound is of great interest and has found numerous applications as a raw material in many chemical industries as well as in medicine and cosmetics. The aim of this study was to evaluate the antioxidant activities of ethanolic extracts obtained from plants containing α-pinene and to test the properties of cosmetic emulsions prepared with these extracts. The raw plant materials consisted of fresh parts of Pinus sylvestris L., such as cones, needles, and branches, as well as dried unground and ground pinecones; dried and fresh Rosmarinus officinalis leaves; dried Levisticum officinale leaves; and dried Salvia officinalis L. leaves. The plant materials were individually extracted with 40% (v/v), 70% (v/v), and 96% (v/v) ethanol using ultrasound-assisted extraction (UAE) for 15, 30, or 60 min. This method is a green extraction technique, frequently applied to isolate active substances from plants. For the selected plant materials, Soxhlet extraction with 96% (v/v) ethanol was also performed. The qualitative and quantitative analyses of the components in the selected extracts were performed with gas chromatography coupled with mass spectrometry (GC-MS). The antioxidant activities of the extracts were evaluated with the DPPH and ABTS methods. The extracts of three plant materials with the highest antioxidant activities—dried Rosmarinus officinalis leaves, dried Salvia officinalis L. leaves, and dried and ground Pinus sylvestris L. cones—were selected to be incorporated in cosmetic emulsions containing glyceryl monostearate and Olivem 1000 as emulsifiers. The stabilities and antioxidant activities of the emulsions were evaluated. Moreover, the antimicrobial properties of the emulsions using microbiological tests were also determined. The findings suggest that the prepared emulsions are stable cosmetic products with a high antioxidant potential.

Geraniol is a compound belonging to the group of monoterpenes that finds many applications in organic syntheses, medicine and cosmetics. The following properties of geraniol and its derivatives are of particular interest in medicine: its anti-inflammatory, antioxidant, antimicrobial and anticancer effects. The geraniol oxidation process was carried out using a mineral of natural origin—vermiculite. Vermiculite is a catalyst that perfectly fits into modern trends in the organic industry, where the aim is to use cheap, renewable and relatively easily available catalytic materials (vermiculite is found on continents including Africa, North America, South America, Australia and Asia). Preliminary studies on the oxidation process of geraniol on vermiculite was carried out in a glass apparatus using molecular oxygen supplied by means of a bubbler and magnetic stirrer with a heating function. During the oxidation process of geraniol on vermiculite, the influence of the following parameters was examined: the temperature, amount of catalyst and reaction time. The main parameters of the process, on the basis of which the most favorable process conditions were selected, were the selectivity of the transformation to 2,3-epoxygeraniol, citral and 2,3-epoxycitral, and the conversion of geraniol. The composition of the post-reaction mixtures was determined qualitatively and quantitatively using the gas chromatography method. In addition, vermiculite was subjected to instrumental tests, such as XRD, SEM, EDX, FTIR and UV-VIS. Moreover, the specific surface area, pore volume and pore volume distribution were estimated on the basis of N2 sorption at −196 °C and also the acid-site concentration in vermiculite was established.

Avocado is a rich source of numerous nutrients, such as micro- and macroelements, essential unsaturated fatty acids, and vitamins essential for the correct functioning of the body. Consequently, its consumption has significantly increased in recent years. The primary edible part of the fruit is the flesh, while the seed is still considered biowaste. Currently, various methods for utilization of this biowaste are being explored, prompting the authors of this work to investigate the catalytic properties of ground avocado seeds. Dried, ground avocado seeds were used as the catalyst in the environmentally friendly oxidation of limonene with oxygen. The process was carried out in mild conditions, without the use of any solvent and at atmospheric pressure. The studies examined the influence of temperature (70–110 °C), the amount of the catalyst (0.5–5.0 wt%), and the reaction time (15–360 min). The analyses of the post-reaction mixtures were performed using the gas chromatography method (GC). The maximum value of the conversion of limonene obtained during the tests was 36 mol%. The main products of this process were as follows: 1,2-epoxylimonene, carveol, and perillyl alcohol. Also, the following compounds were determined in the post-reaction mixtures: carvone and 1,2-epoxylimonene diol. The studied process is interesting, taking into account both the management of waste in the form of avocado seeds and possible wide applications of limonene transformation products in medicine, cosmetics and the food industry. Given that limonene is now increasingly being extracted from waste orange peels, this is also a good way to manage the future naturally derived limonene and reduce the amount of waste orange peels. The presented studies fit perfectly with the goals of sustainable development and circular economy and may be the basis for the future development of “green technology” for obtaining value-added oxygenated derivatives of limonene. These studies show the use of waste biomass in the form of avocado seeds to obtain a green catalyst. In this context, our research presents an effective way of waste valorization.

People are paying more and more attention to their physical appearance. One way is the use of cosmetics containing antioxidants that slow down the skin ageing process. The application of photoprotective agents is another factor that protects the skin against ageing. Preparations based on natural raw materials are considered to be more safe. The evaluation of both antioxidant and photoprotective potential seems to be of interest for formulating new cosmetics. The aim of this study was to evaluate the antioxidant and in vitro photoprotective potential of Lavandula angustifolia alcoholic extracts. Two methods, i.e., DPPH and ABTS, based on spectrophotometric analysis were applied to determine antioxidant activity. Additionally, the in vitro sun protection factor (SPF) of these extracts was determined and a correlation between this parameter and the antioxidant potential of the extracts was also evaluated. The extracts of dry flowers and herbs of lavender were prepared using ultrasound-assisted extraction. As extractants, four short-chain alcohols, i.e., methanol, ethanol, n-propanol, and isopropanol, in three concentrations were applied to obtain the extracts. To evaluate the stability of the extracts, the determination of antioxidant activity by the DPPH and ABTS methods as well as the SPF value in vitro were performed twice: immediately after the preparation of the extracts and twelve months later. Moreover, the GC-MS analysis of certain extracts was also performed. In extracts made in diluted alcohols, a higher antioxidant potential was observed. A similar observation was made for the in vitro SPF determination. A significant correlation was seen between the antioxidant activity determined by the ABTS method and SPF (for herbs analysed immediately after extract preparation and twelve months later, r = 0.713 and 0.936, respectively, and for flower extracts, r = 0.640 and 0.801, respectively). For the DPPH method, a significant correlation was found only for herb extracts (r = 0.520 and 0.623, respectively). In general, slightly higher antioxidant or photoprotective in vitro potential were observed in later-analysed extracts. However, no significant differences were noted between the antioxidant activity or the photoprotection factor of the extracts determined immediately after their preparation and twelve months later, except for the flower extracts evaluated using the DPPH method (p < 0.0001). A very high correlation was found between the SPF values for both herb and flower extracts evaluated immediately and twelve months later, r = 0.953 and 0.899, respectively. Based on the obtained results, the extracts of Lavandula angustifolia Hidcote Blue variety could be considered as a possible component of anti-ageing cosmetics.

The subject of the presented work was the study of the pathways of geraniol transformation during its oxidation with molecular oxygen in the presence of a natural Japanese volcanic clay mineral—mironekuton—used as a green heterogeneous catalyst. Prior to the catalytic tests, a comprehensive characterization of mironekuton was carried out using SEM, XRD, EDX, FTIR, and UV–Vis techniques. The catalytic experiments were aimed at establishing reaction conditions enabling effective geraniol conversion and controlling the distribution of valuable transformation products under solvent-free conditions. The influence of temperature (75–100 °C), catalyst content (0.5–5.0 wt%), and reaction time (15–360 min) was systematically investigated. The obtained results demonstrated that pristine mironekuton exhibits moderate activity and limited selectivity toward low-molecular-weight oxygenated derivatives of geraniol, such as 2,3-epoxygeraniol, 2,3-epoxycitral, and citral. Instead, dehydration, isomerization, and dimerization reactions play a significant role, leading to the formation of higher-molecular-weight products, particularly thunbergol and 6,11-dimethyldodeca-2,6,10-trien-1-ol. Sulfuric acid treatment of mironekuton results in a pronounced enhancement of catalytic activity and a substantial shift in product distribution. This effect is directly related to the increased surface acidity, which promotes dehydration–dimerization pathways over epoxidation, leading to thunbergol as the dominant product with high and reproducible selectivity, while epoxidation products are no longer detected. Kinetic modeling of the geraniol transformation process revealed that epoxidation steps are kinetically disfavored and that epoxide species act only as short-lived intermediates, whereas dehydration–dimerization pathways are kinetically preferred. Overall, the results indicate that acid-activated mironekuton functions as an efficient and environmentally benign heterogeneous catalyst, favoring selective thunbergol formation under mild, solvent-free conditions, using molecular oxygen as a green oxidant.

Cinnamon bark is a rich source of bioactive compounds with antioxidant activity. Such properties are valuable for food applications. Aim of the study was to compare the antioxidant potential of alcoholic extracts obtained from the bark of Cinnamomum verum and Cinnamomum cassia. Ultrasound-assisted extraction was performed using ethanol, methanol, 1-propanol, and 2-propanol at different concentrations and extraction times. Extracts were prepared from broken and ground bark to evaluate the effect of the degree of raw material grinding on extraction efficiency. Antioxidant activity was determined using the DPPH and ABTS assays immediately after extraction and after six months of extracts storage at room temperature. All extracts were analyzed by GC-MS immediately after extraction, while selected extracts prepared from ground bark were re-analyzed after six years of storage. Extracts from ground bark showed higher antioxidant activity than those from broken bark. Antioxidant capacity depended on alcohol and its concentration used for extraction. GC-MS analysis identified cinnamaldehyde derivatives, eugenol, linalool, and other phenolic compounds. Although some statistically significant differences were observed after six months of storage, the antioxidant activity of most extracts remained relatively stable, indicating good preservation of antioxidant properties during storage. These findings suggest that both Cinnamomum verum and Cinnamomum cassia may serve as promising natural antioxidants for food applications.