Bioassays provide an authentication of the traditional knowledge of medicinal plants. Antibacterial, antioxidant and phenolic content of nine medicinal plants (Achillea millefolium, Prunella vulgaris, P. laciniata, Lythrum salicaria, Epilobium angustifolium, E. hirsutum, Pedicularis comosa, Agrimonia eupatoria and Verbena officinalis) were investigated in connection with folkloric usages. Aerial parts of nine plant species were extracted with water and methanol (MeOH). Disc diffusion method was performed to evaluate the antibacterial activity of the extracts against ten pathogenic bacteria. Antioxidant activity was determined by using 2,2-diphenyl-1- picrylhydrazil (DPPH) radical photometric assay. Total phenolic and flavonoid content were investigated by using Folin-Ciocaltaeu and aluminum chloride (AlCl3) colorimetric method, respectively. Quantitative analysis of phenolic constituents of nine plants species were performed by high performance liquid chromatography-diode array detector (HPLC-DAD) via chosen ten phenolic standards (gallic acid monohydrate, caffeic acid, rutin hydrate, luteolin-7-O-β-D glucoside, kaempferol, rosmarinic acid, myricetin, quercetin, coumarin and apigenin). E. hirsutum showed the best antibacterial activity against gram-positive bacteria (S auerus, S. epidermidis and S. pyogenes). L. salicaria also demonstrated strong and broad spectrum antibacterial activity. P. laciniata, L. salicaria and E. angustifolium showed potent antioxidant activity. The highest phenolic and flavonoid content was observed with E. hirsutum and A. millefolium, respectively. L. salicaria also had very high amount of total phenol and flavonoid content. HPLC-DAD analysis displayed that P. laciniata and A. eupatoria were the best sources of rosmarinic acid. Furthermore, V. officinalis and P. vulgaris also had remarkable amount of rutin. This study revealed the scientific rationale behind the traditional knowledge of the tested plants. Consistent with traditional usages, the most prominent plants were L. salicaria, E. hirsutum and E. angustifolium in regard to strong antibacterial and antioxidant potentials. These plants may be proper natural sources with potential applications in pharmaceutical and food industry.

Lichens are a symbiotic relationship between a fungus and a photosynthetic partner. Chemical characterization and bioactive potentials (antiproliferative, antioxidant, and antibacterial) of five lichen species (Evernia prunastri, Platismatia glauca, Pseudevernia furfuracea, Ramalina fastigiata, and Ramalina farinacea) were assessed. Five lichen metabolites (usnic acid, atranorin, stictic acid, evernic acid, and fumarprotocetraric acid) were analyzed by HPLC-DAD. E. prunastri was noteworthy evernic acid source. Antiproliferative activity was evaluated using human breast adenocarcinoma (MCF-7) and human hepatocellular carcinoma (HepG2/C3A) cell lines. The strongest activity was observed for P. glauca against HepG2/C3A, while the only lichen species that induced cytotoxicity against MCF-7 cell line was P. furfuracea. The highest antioxidant activity was also obtained with P. furfuracea. E. prunastri and R. farinaceae had the highest phenolic and flavonoid contents, respectively. Antibacterial activities of the extracts were determined against ten pathogenic bacteria. The most effective antibacterial agent was methanol extract of R. fastigiata. Our findings have revealed the pharmaceutical potentials of tested lichen species.

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Turkish hazel (Corylus colurna L.) is one of the naturally grown hazelnut species in Turkey. It can be easily separated from other hazel species with its thick single stem and tall appearance. It can be used in afforestation and erosion control studies due to low demand for habitat and strong root system. It contains substances with high medicinal value in its fruits and leaves. Hazel leaves have strong antioxidant activity due to their high phenolic content. Objective of the study was primarily to determine the individual phenolic constituents of six different population of Turkish Hazelnut and then to evaluate the effect of water deficiency stress generated by irrigation regime on phenolic constituents and photosystem II activity on these genotypes. Grafted plants were produced by taking scions from six different populations of Turkish Hazelnut (Oğuzlar, Erenler, Merkeşler, Seben, Güney Felakettin and Pelitcik). The study was started when the grafted seedlings were 7 years old in greenhouse. During the experiment (June and July), two different levels of irrigation were applied (W1: the soil was fully irrigated to reach field capacity in each irrigation; W2: 50% reduction of W1 irrigation water). After the application of two different irrigation regimes, leaves were collected for each month, dried, extracted with methanol and then quantitatively analyzed and compared for individual phenolic constituents (gallic acid monohydrate, caffeic acid, rutin hydrate, luteolin-7-O-β-D glucoside, kaempferol, rosmarinic acid, myricetin, quercetin, coumarin and apigenin) by using high performance liquid chromatography (HPLC) coupled with a diode array detector (DAD). Generally, rutin, kaempferol and luteolin were dominant individual phenols in methanol extracts of Turkish hazelnut leaves. Pelitcik population was noticeable source of rutin and kaempferol in June, and the halved irrigation regime significantly increased the levels of both phenols in July. Similarly, the highest total phenolic content was observed in the Pelitcik population in June and the halved irrigation regime significantly increased the total phenolic content in both months in this population. It was also determined to what extent water deficiency physiologically affects the quantum efficiency (Fv/Fm) of photosystem II activity through chlorophyll fluorescence technique in hazelnut leaves. Generally, Fv/Fm value decreased with water deficiency. This study showed that water deficiency stress generally caused an increase in phenolic constituents in Turkish Hazel leaves and they may be proper natural sources of phenolic constituents with abiotic stress applications in pharmaceutical and food industry.