https://pubs.rsc.org/en/content/articlepdf/2019/NP/C8NP00092A

Marine natural products.

Flavonoids, a group of natural substances with variable phenolic structures, are found in fruits, vegetables, grains, bark, roots, stems, flowers, tea and wine. These natural products are well known for their beneficial effects on health and efforts are being made to isolate the ingredients so called flavonoids. Flavonoids are now considered as an indispensable component in a variety of nutraceutical, pharmaceutical, medicinal and cosmetic applications. This is attributed to their anti-oxidative, anti-inflammatory, anti-mutagenic and anti-carcinogenic properties coupled with their capacity to modulate key cellular enzyme function. Research on flavonoids received an added impulse with the discovery of the low cardiovascular mortality rate and also prevention of CHD. Information on the working mechanisms of flavonoids is still not understood properly. However, it has widely been known for centuries that derivatives of plant origin possess a broad spectrum of biological activity. Current trends of research and development activities on flavonoids relate to isolation, identification, characterisation and functions of flavonoids and finally their applications on health benefits. Molecular docking and knowledge of bioinformatics are also being used to predict potential applications and manufacturing by industry. In the present review, attempts have been made to discuss the current trends of research and development on flavonoids, working mechanisms of flavonoids, flavonoid functions and applications, prediction of flavonoids as potential drugs in preventing chronic diseases and future research directions.

/pdf/flavonoids-an-overview-5gkev1wgy2.pdf

Flavonoids: an overview

Male circumcision for HIV prevention in young men in Kisumu, Kenya : a randomised controlled trial. Commentary

Medicinal plants of India with anti-diabetic potential.

While use of synthetic antioxidants (such as butylated hydroxytoluene and butylated hydroxyanisole) to maintain the quality of ready-to-eat food products has become commonplace, consumer concern regarding their safety has motivated the food industry to seek natural alternatives. Phenolic antioxidants can inhibit free radical formation and/or interrupt propagation of autoxidation. Fat-soluble vitamin E (α-tocopherol) and water-soluble vitamin C (L-ascorbic acid) are both effective in the appropriate matrix. Plant extracts, generally used for their flavoring characteristics, often have strong H-donating activity thus making them extremely effective antioxidants. This antioxidant activity is most often due to phenolic acids (gallic, protocatechuic, caffeic, and rosmarinic acids), phenolic diterpenes (carnosol, carnosic acid, rosmanol, and rosmadial), flavonoids (quercetin, catechin, naringenin, and kaempferol), and volatile oils (eugenol, carvacrol, thymol, and menthol). Some plant pigments (anthocyanin and anthocyanidin) can chelate metals and donate H to oxygen radicals thus slowing oxidation via 2 mechanisms. Tea and extracts of grape seeds and skins contain catechins, epicatechins, phenolic acids, proanthocyanidins, and resveratrol, all of which contribute to their antioxidative activity. The objective of this article is to provide an overview of natural antioxidants, their mechanisms of action, and potential applications.

https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1541-4337.2011.00156.x

Natural antioxidants: sources, compounds, mechanisms of action, and potential applications

Most of the bulbous plants are known for their medicinal purposes in addition to their ornamental value. Turkey is one of the home country of many beautiful bulbous plants. In continuation of our extensive studies on finding new natural cholinesterase inhibitors from Turkish medicinal plants, Iris L. species were investigated for their in vitro cholinesterase inhibitory effects designed to assess cholinesterase inhibitor activities on both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) and antioxidant capacities with respect to their neuroprotective potential in this study. The dichloromethane and methanol extracts prepared from the bulbs of 47 Iris taxa were screened by using modified Ellmann method and the highest butyrylcholinesterase inhibitory effect was found in the methanol extract of the bulbs of Iris pseudacorus L. The dichloromethane sub-extract, which is obtained bioactivity-guided fractionation of methanol extract of I. pseudacorus L., was exhibited significant butyrylcholinesterase inhibitory activity (73.65 ± 2.06 %). These active sub-extract was subjected to fractionation on column chromatography and obtained six fractions. Among the fractions, coded as N5 was shown the significant butyrylcholinesterase inhibitory activity (93.78 ± 1.49 %) compared with galanthamine (80.02 ± 0.12 %). Fractionation of N5 on flash chromatography the highest butyrylcholinesterase inhibitory activity of sub-fraction coded as DS-5 was determined as 94.00 ± 1.03 %. The responsible compound from the activity of this sub-fraction was detected as irisolidone glucopyranoside based on its mass data by using LC-ESI-Q/TOF-MS-MS technique.

/pdf/isolation-and-identification-of-cholinesterase-inhibitors-5bmoo9jgih.pdf

Isolation and Identification of Cholinesterase Inhibitors from the Bulbs of Iris pseudacorus L.

Taksol ve türevleri̇ni̇n bi̇yosentezi̇ : the biosynthesis of taxol and derivatives

GenusTaxus(Taxaceae) is represented by eight species and two hybrids in the world. HoweverTaxushas only one species growing in TurkeyTaxus baccataL. (European yew)1,2. Many compounds such as taxoids, lignans, flavonoids, steroids, diterpenoids and sugar derivatives have been isolated commonly in this genus3,4.

Lignans from Taxus baccata L.

Separation and Determination of Solanaceous Alkaloids by High-Performance Liquid Chromatography

Many of the Turkish medicinal plants have useful medicinal aspects and contain alkaloids of potential medicinal uses. Continuing our researches carried out on various medicinal plants have resulted in the isolation and structure elucidation of new and known alkaloids. During the last ten years, the isolation and structure elucidation of several new alkaloids from Fumaria, Corydalis, Ruta, Haplophyllum, Galium, Leucojum, Buxus, Thermopsis, Senecio, Consolida and Veratrum species growing in Turkey have been completed.

Bilge Sener

Papers

Isolation and Identification of Cholinesterase Inhibitors from the Bulbs of Iris pseudacorus L.

Taksol ve türevleri̇ni̇n bi̇yosentezi̇ : the biosynthesis of taxol and derivatives

Lignans from Taxus baccata L.

Separation and Determination of Solanaceous Alkaloids by High-Performance Liquid Chromatography

New Alkaloids of Some Turkish Medicinal Plants