Herb

About: Herb is a research topic. Over the lifetime, 1167 publications have been published within this topic receiving 17103 citations. The topic is also known as: herbs.

Antioxidant activity of plant extracts containing phenolic compounds

Abstract: The antioxidative activity of a total of 92 phenolic extracts from edible and nonedible plant materials (berries, fruits, vegetables, herbs, cereals, tree materials, plant sprouts, and seeds) was examined by autoxidation of methyl linoleate. The content of total phenolics in the extracts was determined spectrometrically according to the Folin-Ciocalteu procedure and calculated as gallic acid equivalents (GAE). Among edible plant materials, remarkable high antioxidant activity and high total phenolic content (GAE > 20 mg/g) were found in berries, especially aronia and crowberry. Apple extracts (two varieties) showed also strong antioxidant activity even though the total phenolic contents were low (GAE < 12.1 mg/g). Among nonedible plant materials, high activities were found in tree materials, especially in willow bark, spruce needles, pine bark and cork, and birch phloem, and in some medicinal plants including heather, bog-rosemary, willow herb, and meadowsweet. In addition, potato peel and beetroot peel extracts showed strong antioxidant effects. To utilize these significant sources of natural antioxidants, further characterization of the phenolic composition is needed.

Spices and herbs: their antimicrobial activity and its determination

Abstract: Throughout the years numerous investigations concerning the inhibition of microorganisms by spices, herbs, their extracts, essential oils and various constituents have been reported Many of these materials possess significant antimicrobial activity, which in many cases is due primarily to a particular constituent Interpretation and comparison of results of various studies is complicated by variations in the methodology used for the determination of antimicrobial activity The antimicrobial activity varies depending on the microorganism, the spice or herb and the test medium These and other factors are examined in the light of their effect on the outcome of the test method

The effect of herbs and their associated essential oils on performance, dietary digestibility and gut microflora in chickens from 7 to 28 days of age.

Abstract: 1. The effect of the dietary inclusion of 5 culinary herbs or their essential oils on the growth, digestibility and intestinal microflora status in female broiler chicks was assessed. From 7 to 28 d of age, either a basal control diet without supplement was given or one of 10 others, consisting of the basal diet with either 10 g/kg herb (thyme, oregano, marjoram, rosemary or yarrow) or 1 g/kg of essential oil. 2. Body mass (BM) and feed consumption (AFC) were measured on a weekly basis and used to calculate chick performance. Total viable counts of lactic acid bacteria, coliforms, anaerobes and Clostridium perfringens were determined at 25 d. Apparent nutrient digestibilities were calculated from the measured values for gross energy, nitrogen (N), dry matter (DM) and organic matter, and sialic acid concentration was also measured. 3. Generally, dietary thyme oil or yarrow herb inclusion had the most positive effects on chick performance, while oregano herb and yarrow oil were the poorest supplements. Only...

The allelopathic effects of Eucalyptus camaldulensis.

Abstract: In California the annual vegetation adjacent to natural- ized stands of Eucalyptus camaldulensis often is inhibited severely. Annual herbs rarely survive to maturity where Eucalyptus litter accu- mulates. In the ecotone between the trees and herbs a "bare zone," lacking both litter and significant herbaceous vegetation, often is encoun- tered. The occasional herb occurring in this zone is stunted less severely than those in the litter. Grassland of gradually increasing vigor begins at the edge of the bare zone. This pattern was not explained by differences in edaphic conditions, differential grazing, seed removal, or competition for light or nutrients. Competition for water was significant in the production of bare zones, but was not responsible for the lack of herbs in the litter zone. Here soil moisture levels were usually comparable to those in the grassland. Several volatile and water-soluble toxins were found in Eucalyptus tissues. Cineole and a-pinene, both highly toxic terpenes, were found adsorbed to colloidal soil particles of the litter and bare zones. Adsorbed terpenes were toxic to germinating seeds and seedlings. Water-soluble toxins found in the litter inhibited herb growth in laboratory, green- house, and field experiments. Of 10 isolated phenolic toxins, five were identified as caffeic acid, chlorogenic acid, p-coumaric acid, ferulic acid,