The results give a scientific basis to the traditional utilization of these Juniperus species, also demonstrating their potential as sources of natural antioxidant and antimicrobial compounds.

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Avocado (Persea americana Mill.) is a member of Lauraceae with one-seeded berry fruit and cultivated in all tropical, subtropical regions in the world and in the Southern coast region of Turkey. Oxidative damage caused by UV can trigger inflammation, resulting in serious inflammatory skin diseases including eczema, seborrheic dermatitis, hyperpigmentation and ageing. Enzyme inhibitors involved in melanogenesis, such as tyrosinase, have been used recently for hyperpigmentation and skin diseases in cosmetic products. Objective: This study aimed to evaluate the antioxidant, anti-inflammatory, anti-tyrosinase activities and total polyphenolic contents of the different parts of P. americana fruit. Methods: The fruit was divided into exocarp, mesocarp, seed, and then methanol and n-hexane extracts were prepared. DPPH and ABTS free radical scavenging capacities and inhibitory potentials on lipid peroxidation were determined to investigate the antioxidant potentials of the extracts. Anti-inflammatory activities of the extracts were evaluated by measuring the stabilization level of the human red blood cell membrane. The tyrosinase inhibitory activities of the samples were determined using mushroom tyrosinase. Results: In general methanol extracts possessed remarkable higher DPPH free radical scavenging activities than n-hexane extracts. The highest activity was determined in methanol extracts of seed (4.17 ± 0.04 mg/mL) followed by exocarp (5.25 ± 0.05 mg/mL). Overall methanol extracts possessed higher ABTS free radical scavenging activities than n-hexane extracts. The greatest ABTS free radical scavenging activity was obtained in methanol extracts of seed (0.03 ± 0.01 mg/mL). In the anti-lipid peroxidation assay, the greatest activity was noticed in methanol extracts of seed (7.71 ± 0.36 µg/mL) followed by exocarp (12.12 ± 0.34 µg/mL), while all n-hexane extracts were inactive. Overall methanol extracts exhibited higher anti-inflammatory and antioxidant properties than n-hexane extracts. However, the maximum anti-tyrosinase activity was determined in n-hexane extracts of exocarp (0.40 ± 0.01 mg/mL) followed by seed (0.46 ± 0.01 mg/mL). Conclusions: These extracts are promising candidates for use as natural products-based antioxidant and anti-inflammatory properties in inflammation-related disease, and also anti-tyrosinase properties in dermatological applications.

Erica species (Ericaceae) are widely used due to their medicinal properties in Turkish folk medicine. In this study, the antioxidant capacities of the extracts with different polarities of the aerial parts of Erica arborea, E. manipuliflora, E. bocquetii and E. sicula subsp. libanotica native to Turkey were investigated. 1,1-diphenyl-2-picrylhydrazyl (DPPH •) radical scavenging and the thiobarbituric acid (TBA) test systems used for the determination of antioxidant capacities. Also, total phenol contents in the extracts were determined as spectrophotometric. All extracts exhibited strong scavenging activity against DPPH except the chloroform extracts. Ethyl acetate extracts of Erica species had the best scavenging activity against DPPH, as well as the highest DPPH scavenging activity was exhibited by E. manipuliflora and E. bocquetii with IC50 values of 0.002±0.001 and 0.004±0.000 µg/mL, respectively. In TBA test, the highest activity was observed in the ethyl acetate extract of E. manipuliflora (IC50= 0.001±0.000 µg/mL), followed by the water extract of this plant (0.03± 0.005 µg/mL). The highest total phenolic content was found in the ethyl acetate extracts ranging from 875.5 to 701.7 mg GAE/g extract. Our results showed that the ethyl acetate extracts of Erica taxa are rich in natural antioxidant substances.

Objective: Oak species are medicinal plants with traditional use around the world. These species, which are very rich in tannins, have potential as antibacterial agents in terms of the polyphenolic compounds content. In this study, the antibacterial potential and phytochemical content of the branches and leaves of Quercus macranthera subsp. syspirensis, which is endemic to Turkey, were investigated.Material and Method: Plant materials were collected from Araç (Kastamonu/Turkey) in 2020. Methanol extracts were prepared from dried and powdered branches and leaves. The antibacterial activity test was evaluated by broth microdilution method as a minimal inhibition concentration (MIC) against Staphylococcus