In vitro bioaccessibility and activity of Greek oregano (Origanum vulgare L. ssp. hirtum (link) Ietswaart) compounds as affected by nitrogen fertilization

Abstract

BACKGROUND Greek oregano is a culinary and medicinal herb native to the Mediterranean region; however nowadays it is cultivated in many regions all over the world. It is commonly used as a spice for flavoring food products and in various traditional medicine applications. This study investigated the effect of nitrogen fertilization at 0–150 kg N ha−1 on the potential bioaccessibility and activity of Greek oregano compounds. For this purpose the total phenolic content, rosmarinic acid content, and antioxidant activities of the raw material, as well as digested fractions, were determined. RESULTS Nitrogen fertilization had a negative influence on the phenolic content and antioxidant activity of raw material; however, its effect on the potential bioaccessibility varied depending on the dose. The highest potential bioaccessibility and activity was determined for plants fertilized with 30 kg N ha−1. For the gastric and intestinal phases of digestion, the potential bioaccessibility percentages were 39.5% and 29.6% for total phenolics, 53.1% and 11.2% for rosmarinic acid content, 45.2% and 44.4% for antiradical activity against 2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS), 39.2% and 27.2% for antiradical activity against 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 50.2% and 23.4% for reducing power, respectively. CONCLUSION The results showed that nitrogen fertilization is an important factor determining the in vitro bioaccessibility of Greek oregano compounds. Furthermore, the nutraceutical potential of herbs, in term of the bioaccessibility of bioactive compounds, may be optimized during plant cultivation by applying an accurate nitrogen level. © 2020 Society of Chemical Industry

Chemical Characteristics and Antioxidant Activity of Arctostaphylos uva-ursi L. Spreng. at the Southern Border of the Geographical Range of the Species in Europe

“…Furthermore, compared with other valuable natural sources of antioxidants, e.g., Greek oregano, whose extracts and by-products are recognized as strong antioxidant agents for food preservation [74], higher antioxidant activity was determined for bearberry. Previous studies indicate that the antiradical activity in Greek oregano ranged from 150.8 to 235.1 mg TE g −1 against ABTS, from 101.8 to 160.7 mg TE g −1 against DPPH, and from 73.2 to 114.4 TE g −1 of ferric reducing power, depending on cultivation conditions (nitrogen dose), in the case of the same analytical procedures [75]. Figure 12 shows the results of the PCA ordination of the bearberry samples.…”

Response of Phenolic Compounds in Lippia graveolens Kunth Irrigated with Aquaculture Wastewater and Steiner Solution

“…According to Bueno-Duran [12], different spectra of light affect the monoterpene content; based on this, red light increases the carvacrol content, blue light increases the thymol content in L. graveolens, and UV-C light application increases the total phenolic content [13]. Moreover, nitrogen deficiency enhances secondary metabolites' production, such as phenolic compounds and flavonoids in Greek oregano [14].…”

Wheat rolls fortified with Greek oregano (Origanum vulgaressp.hirtum(Link) Ietswaart) leaves – phytochemical changes during processing and simulated digestion, nutrient digestibility, and functional properties

“…family native to the northeast regions of the Mediterranean basin i.e. Greece, the Balkans, Turkey, and Cyprus, 14 Besides the areas of natural occurrence, this plant is cultivated worldwide because of its versatile uses as a culinary, medicinal, aromatic, melliferous, and ornamental herb. 15,16 The main purpose of the use of Greek oregano is to flavor such dishes as soups, salads, sauces, and meats; however, it is also used as a natural preservative to protect against deterioration and prolong the storage time of various foods.…”

“…15,16 The main purpose of the use of Greek oregano is to flavor such dishes as soups, salads, sauces, and meats; however, it is also used as a natural preservative to protect against deterioration and prolong the storage time of various foods. 14 In traditional phytotherapy, oregano-derived medications have been employed for the prevention and treatment of cold, cough, headache, diabetes, and digestive disorders. 17,18 Furthermore, previous scientific data have shown that this herb is characterized by a wide range of beneficial activities, such as antibacterial, antifungal, antioxidant, anti-inflammatory, antiproliferative, antispasmodic, diaphoretic, sedative, diuretic, tonic, and carminative activity.…”

“…[15][16][17][18] The promising properties of Greek oregano are mainly attributed to two major groups of its phytochemicalsessential oils and phenolic compounds, with essential oils mainly regarded as substances responsible for powerful antimicrobial properties and phenolic compounds associated with multidirectional antioxidant, anti-inflammatory, and anti-cancer activity. 14,17,18 One of the primary phenolic compounds in Greek oregano and in other members of the Labiatae (Juss.) family is rosmarinic acid.…”