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The CDC25 phosphatases regulate the cell division cycle by controlling the activity of cyclin-dependent kinases. While screening for inhibitors of phosphatases among natural products we repeatedly found that some polyprenyl-hydroquinones and polyprenyl-furans (furanoterpenoids) (furospongins, furospinosulins) were potent CDC25 phosphatase inhibitors. These compounds were extracted, isolated and identified independently from three sponge species (Spongia officinalis, Ircinia spinulosa, Ircinia muscarum), collected at different locations in the Mediterranean Sea. The compounds were inactive on the Ser/Thr phosphatase PP2C-alpha and on three kinases (CDK1, CDK5, GSK-3), suggesting that some potent and selective CDC25 phosphatase might be designed from these initial structures.

Some Viburnum species are used for preparation of the traditional drink called gilaburu in Anatolia. In the current study, our goal was to evaluate acetylcholinesterase (AChE) inhibitory and antioxidant activities of the ethyl acetate, methanol, and water extracts prepared from the branches, leaves, and fruits of Viburnum opulus and Viburnum lantana along with salicin, amentoflavone, and chlorogenic acid, three major compounds abundantly found in these species. AChE enzyme inhibition was tested in vitro using an enzyme-linked immunosorbent assay microplate reader at 50, 100, and 200 μL/mL concentrations. Antioxidant activity was examined by ferrous ion chelating capacity, ferric reducing antioxidant power, and β-carotene bleaching assay at 500, 1,000, and 2,000 μg/mL. Total phenol and flavonoid contents of the extracts were also established by Folin-Ciocalteau and AlCl(3) reagents, respectively. Our data revealed that the leaf methanol extract of V. opulus displayed a significantly high inhibitory effect against AChE (57.63 ± 1.23%, 87.41 ± 0.99%, and 93.19 ± 0.87% at 50, 100, and 200 μg/mL, respectively). The extracts of V. lantana exerted higher antioxidant activity.

Sage is commonly consumed as a herbal tea in Anatolia, where not only Salvia species, but also Sideritis species are called "sage" by the local people. Therefore, it was decided to investigate the most common species of sage-called plants sold in aktars. Eighty-seven samples randomly purchased from 21 provinces throughout Turkey were identified, which finally led to the identification of 7 species; Salvia tomentosa, Salvia fruticosa, Sideritis congesta, Sideritis pisidica var. termessi, Sideritis arguta, Sideritis perfoliata and Sideritis libanotica subsp. linearis. Infusions prepared from all samples were preliminarily tested for their antioxidant activity and 7 representative species were further evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, ferrous ion-chelating and ferric-reducing antioxidant power (FRAP) tests at 0.25, 0.50, and 1.0 mg ml-1 and for their antiacetylcholinesterase activity. The infusions were subjected to the DPPH bioautographic revelatory test, which led to the conclusion that a flavonoid derivative seemed to be responsible for the antioxidant activity in Sideritis congesta and S. pisidica var. termessi

The ethyl acetate, methanol, and water extracts of 16 Ballota species (Family Lamiaceae)-Ballota acetabulosa, Ballota antalyanse, Ballota cristata, Ballota glandulosissima, Ballota inaequidens, Ballota larendana, Ballota latibracteolata, Ballota macrodonta, Ballota nigra ssp. anatolica, B. nigra ssp. foetida, B. nigra ssp. nigra, B. nigra ssp. uncinata, Ballota pseudodictamnus ssp. lycia, Ballota rotundifolia, Ballota saxatilis ssp. brachyodonta, and B. saxatilis subsp. saxatilis-were screened for their 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical quenching, ferric-reducing antioxidant power, and ferrous ion-chelating capacity at 1mg/mL. Hispanolone, a major diterpene found in the Ballota genus, was also tested in the same manner. Total phenol and flavonoid contents of the extracts were determined by Folin-Ciocalteau and AlCl(3) reagents, respectively. The extracts showed insignificant quenching activity against DPPH radical, but they had moderate antioxidant activity (0.597 ± 0.03 to 1.342 ± 0.01) in the ferric-reducing test compared to chlorogenic acid (the reference compound) (3.618 ± 0.01). All of the extracts (ranging from 65.1 ± 0.64% to 96.3 ± 0.09%) and hispanolone (97.31 ± 0.30%) exerted a remarkable ferrous ion-chelating effect. The highest total phenol (gallic acid equivalent) and flavonoid (quercetin equivalent) contents were found in the ethyl acetate extract of B. glandulosissima (393.7 ± 3.03 and 140.6 ± 1.97 mg/g of extract, respectively). Therefore, Ballota species could be a good source of natural preservatives in foodstuffs.

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