Antioxidant and antimicrobial activity in the seeds of Origanum vulgare L. subsp. gracile (C. Koch) Ietswaart and Origanum acutidens (Hand.-Mazz.) Ietswaart from Turkey

Origanum heracleoticum Essential Oils: Chemical Composition, Phytotoxic and Alpha-Amylase Inhibitory Activities

Many studies have demonstrated the herbicidal effects of several essential oils and their possible use as substitutes for chemical herbicides. Several enzymes play a very significant role in seed germination: among these, α-amylase could be involved in essential oil phytotoxic processes. The aims of this study were to compare the chemical composition of the essential oils of two ecotypes of O. heracleoticum growing in Cilento (Southern Italy) and to study their possible use as natural herbicide using Raphanus sativus, Sinapis arvensis and Lolium multiflorum seeds. Moreover, a possible inhibitory activity on the α-amylase enzyme extracted from germinating seeds was evaluated as a possible mechanism of action. Both oils, characterized by GC-MS, belonged to a carvacrol chemotype. The alpha-amylase activity was determined using DNSA (dinitrosalicylic acid) assay quantifying the reducing sugar produced. Furthermore, the essential oils demonstrated phytotoxicity at the highest dose tested, and an inhibitory effect on α-amylase, probably correlated with the phytotoxic effects, was registered. The oils showed interesting phytotoxic and alpha-amylase inhibitory activities, which deserve to be further investigated.

The biochemical content and antioxidant capacities of endemic Tanacetum densum (Lab.) Schultz Bip. subsp. laxum, and Tanacetum densum (Lab.) Schultz Bip. subsp. amani Heywood growing in Turkey

Abstract Medicinal plants have a significant role in preventing and curing several diseases, and Tanacetum L. is one of these plants. The aim of the present study is to determine the fatty acid, lipid-soluble vitamin, sterol, phenolic content, and antioxidant capacity of Tanacetum densum subsp. laxum and Tanacetum densum subsp. amani, to compare the effect of altitude on the biochemical content and to compare systematically by using fatty acids and phenolics. This study showed that palmitic acid (C16:0) and stearic acid (C18:0) are major sources of saturated fatty acid and oleic acid (C18:1 n9), and linoleic acid (18:2 n6c) and a-linolenic acid (C18:3 n3) are the principal unsaturated fatty acids in the two endemic Tanacetum densum taxa. Also, this study found that the unsaturated fatty acid content (60.11±1.61%) of Tanacetum densum subsp. laxum was higher than the unsaturated fatty acid content (44.13±1.28%) of Tanacetum densum subsp. amani. And also, the ω6/ω3 ratio of Tanacetum densum subsp. laxum (1.74) and Tanacetum densum subsp. amani (1.60) was found to be similar. However, this study determined that the lipid soluble vitamin and sterol content of two endemic Tanacetum taxa are low except for stigmasterol. Present study showed that catechin is principal phenolic in the Tanacetum densum taxa. This study also found that Tanacetum densum subsp. laxum and Tanacetum densum subsp. amani had the highest levels of catechin, vanillic acid, and caffeic acid content though the phenolic amounts, particularly catechin and quercetin, were dissimilar in the T. densum taxa. This study suggested that ecological conditions such as altitude may affect the biochemical content of two endemic Tanacetum densum taxa. Furthermore, the current study determined that two endemic Tanacetum L. taxa had potent radical scavenging capacities and found a correlation between total phenolics and antioxidant activity.

Biochemical parameters and antioxidant property of three Salvia L. taxa endemic in Turkey

The aim of the present study was to determine and compare the fatty acids, lipid soluble vitamins, sterols, phenolics, and antioxidant capacities of three endemic Salvia L. taxa (S. euphratica var. Montbret & Aucher ex Bentham leiocalycina (Rech. Fil.) Hedge, S. euphratica var. Montbret & Aucher ex Bentham euphratica (Rech. Fil.) Hedge and S. pseudoeuphratica Rech.Fil.) and to evaluate these results systematically. The fatty acid compositions were determined by using gas chromatography, while the lipid soluble vitamins, sterols, and phenolics were determined by using HPLC. Also, the antioxidant capacities of three Salvia taxa were measured in vitro. Palmitic acid was found as major saturated fatty acid while oleic acid, linoleic acid, α-linolenic acid, and erucic acid were found as major unsaturated fatty acids in the present study. It was found that S. euphratica var. euphratica had lower palmitic acid (8.94 ± 0.71%), total saturated fatty acid (19.16 ± 0.15%), and higher unsaturated fatty acid content (82.08 ± 0.52%) than other studied taxa. Furthermore, it was shown that S. euphratica var. euphratica had different 18.3/18:2 (0.36) unsaturated/saturated fatty acid (4.28) ratios. However, this study demonstrated that Salvia taxa had low lipid soluble vitamins, sterol contents. On the other hand, it was shown that Salvia taxa had similar catechin (509.2 ± 4.21 µg/g and 552.2 ± 9.21 µg/g) and vanillic acid amounts (351.2 ± 2.17 µg/g and 396.8 ± 4.1 µg/g) in this study. And also, it was found that Salvia taxa had high rosmarinic acid content while S. euphratica var. leiocalycina had the highest rosmarinic acid content (1480 ± 7.57 µg/g). On the other hand, it was shown that the two ferulic acid contents of S. euphratica varieties were higher (1175 ±/5.21 µgmg-1740.2 ± 4.82 µg/mg) than the ferulic acid content of S. pseudoeuphratica of which was the lowest (19.2 ± 0.97 µg/mg). The present results suggested that the biochemical results guided the morphological studies, and Salvia taxa have a potent antioxidant capacity.

Chemical compositions, radical scavenging capacities and antimicrobial activities in seeds of Satureja hortensis L. and Mentha spicata L. subsp. spicata from Turkey

The present study determined some biological compounds, radical scavenging activity and antimicrobial capacity in seeds of Satureja hortensis L. and Mentha spicata L. subsp. spicata. Alpha-linolenic acid (C18:3 n3) has been found to be the major polyunsaturated fatty acid of Satureja hortensis L. (66.24 ± 1.24%) and Mentha spicata L. subsp. spicata (48.17 ± 1.01%). Linoleic acid (C18:2 n6) is identified as the second major polyunsaturated fatty acid in the present study and oleic acid (C18:1 n9) is determined as the major monounsaturated fatty acid. Current study showed that Satureja hortensis L. and Mentha spicata L. subsp. spicata have low levels of saturated fatty acids. It has been demonstrated that ergosterol (263.1 ± 2.14 µg/g), stigmasterol (39.07 ± 0.91 µg/g) and beta-sitosterol (14.64 ± 0.49 µg/g) have been found in Mentha spicata L. subsp. spicata, while ergosterol (69.41 ± 1.75 µg/g) and beta-sitosterol (19.81 ± 1.14 µg/g) have been determined in Satureja hortensis L. Also, this study determined that Satureja hortensis L. and Mentha spicata L. subsp. spicata have low lipide-soluble vitamin content. Furthermore, it has been found that Satureja hortensis L. contains naringenin (612.57 ± 2.57 µg/g), morin (86.97 ± 1.12 µg/g), quercetin (22.87 ± 0.75 µg/g), and kaempferol (20.11 ± 0.94 µg/g) while naringenin (135.91 ± 1.91 µg/g), naringin (61.23 ± 2.15 µg/g) and quercetin (47.51 ± 1.17 µg/g) have been detected as major flavonoids in the seeds of Mentha spicata L. subsp. spicata. The results of the present study suggest that methanol extracts of Satureja hortensis L. and Mentha spicata L. subsp. spicata have significant free radical scavenging activity. The present results revealed that Satureja hortensis L. and Mentha spicata L. subsp. spicata showed major activity against gram-positive and gram-negative microorganisms, fungi and yeast.