Biological effects of essential oils - A review

With digital equipment becoming increasingly networked, either on wired or wireless networks, for personal and professional use alike, distributed software systems have become a crucial element in information and communications technologies. The study of these systems forms the core of the ARLES' work, which is specifically concerned with defining new system software architectures, based on the use of emerging networking technologies. In this context, we concentrate on the study of distributed systems which bring to life the vision of ubiquitous computing systems, also known as ambient intelligence.

반도체 공정 overview

Phenolics and polyphenolics in foods, beverages and spices: Antioxidant activity and health effects – A review

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

Total equivalent antioxidant capacity (TEAC) and phenolic content of 26 common spice extracts from 12 botanical families were investigated. Qualitative and quantitative analyses of major phenolics in the spice extracts were systematically conducted by reversed-phase high-performance liquid chromatography (RP-HPLC). Many spices contained high levels of phenolics and demonstrated high antioxidant capacity. Wide variation in TEAC values (0.55−168.7 mmol/100 g) and total phenolic content (0.04−14.38 g of gallic acid equivalent/100 g) was observed. A highly positive linear relationship (R2 = 0.95) obtained between TEAC values and total phenolic content showed that phenolic compounds in the tested spices contributed significantly to their antioxidant capacity. Major types of phenolic constituents identified in the spice extracts were phenolic acids, phenolic diterpenes, flavonoids, and volatile oils (e.g., aromatic compounds). Rosmarinic acid was the dominant phenolic compound in the six spices of the family La...

Antioxidant Capacity of 26 Spice Extracts and Characterization of Their Phenolic Constituents

The Stevia genus (Asteraceae) comprises around 230 species, distributed from the southern United States to the South American Andean region. Stevia rebaudiana, a Paraguayan herb that produces an intensely sweet diterpene glycoside called stevioside, is the most relevant member of this genus. Apart from S. rebaudiana, many other species belonging to the Stevia genus are considered medicinal and have been popularly used to treat different ailments. The members from this genus produce sesquiterpene lactones, diterpenes, longipinanes, and flavonoids as the main types of phytochemicals. Many pharmacological activities have been described for Stevia extracts and isolated compounds, antioxidant, antiparasitic, antiviral, anti-inflammatory, and antiproliferative activities being the most frequently mentioned. This review aims to present an update of the Stevia genus covering ethnobotanical aspects and traditional uses, phytochemistry, and biological activities of the extracts and isolated compounds.

https://www.mdpi.com/1420-3049/26/9/2733/pdf

Stevia Genus: Phytochemistry and Biological Activities Update.

14,15-Dihydroxygermacranolides and Other Constituents of Mikania minima

In Algerian traditional medicine, the aerial parts of Ammoides atlantica (Coss. et Dur.) Wolf. (Apiaceae) are reported to have a wide range of biological activities such as antibacterial and antidiarrheic activity. The in vitro antibacterial activity of the oil was evaluated by Disc diffusion method against several strains of bacteria, and this activity was shown to be very strong against most of the tested microorganisms, especially Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, and Enterococcus faecalis ATCC 29212. The MIC was also carry out and Bacillus subtilis ATCC 6633 (vegetative form) resulted to be the most sensitive microorganism with a MIC value inferior of 6.25 mg/L. The essential oil was analyzed by GC and GC/MS. The main components were thymol (53.2%), γ-terpinene (19.4%) and p-cymene (10.6%).

César A.N. Catalán

Papers

Stevia Genus: Phytochemistry and Biological Activities Update.

14,15-Dihydroxygermacranolides and Other Constituents of Mikania minima

Composition and Antibacterial Activity of The Essential Oil of Ammoides atlantica (Coss. et Dur.) Wolf

Glaucolides from Vernonia fulta

Kaempferol 3-α-d-glucopyranoside-7-α-l-rhamnopyranoside from Erythroxylon cuneifolium