Flavonoids rosemary

Nowadays, consumers would like those antioxidants present in food products not only to stabilise food lipids, but also to be absorbed through the intestinal wall and protect the lipids of blood plasma against oxidation. This effect is relatively evident in the case of tocopherols (which are liposoluble) or ascorbic acid (which is hydrophilic), but much less evidence is available on antioxidants of medium polarity, such as flavonoids, rosemary oleoresins or green or black tea catechins. 

Negative atmospheric pressure chemical ionization (APC) low-energy collision activation mss spectrometry has also been employed for the characterization of flavonoids in extracts of fresh herbs. Besides the separation, quantitative determination and identification of flavonoids, the objective of the study was the comparison of the efficacy of the various detection systems in the analysis of flavonoids in herb extracts. Freeze-dried herbs (0.5g of chives, cress, dill, lovage, mint, oregano, parsley, rosemary, tarragon and thyme) were ground and extracted with 20 ml of 62.5 per cent aqueous methanol. After sedimentation the suspension was filtered and used for HPLC analyses. Separations were carried out in an... 

Spices (rosemary, sage, thyme) contain considerable amounts of flavonols and flavones, mainly in the glycoside form (154). Thus, phenolic analyses in spices were often considered in order to determine the optimum time for plant collection to give maximum flavonoid contents and for health benefits (154,155). Flavonoids (naringin, luteolin, apigenin, and chrysoeriol) were extracted from spices using a percolation process at room temperature with solvents (MeOH and EtOAc), and HPLC analysis was carried out (155). 

Main components 1-3% essential oil, rosemary acid (primarily responsible for the antioxidating effect of sweet marjoram), ursolic and oleanolic acid, phenols like arbutin [152], flavonoids [153, 154]. 

Main components 1.5-2.5% essential oil, rosemarinic acid (see rosemary), flavonoids [266, 267], tannins, oleanolic and ursolic acid. 

The flavonoids are a group of secondary metabolites widely distributed in the plant kingdom [63]. In 1984, more than 4000 flavonoids were identified in plants [64]. The major dietary sources of flavones are spices and pot herbs, such as parsley, rosemary, and thyme [65], whereas flavonols are predominantly found in onions, kale, broccoli, apples, berries and cherries, and in tea and red wine [66]. The flavanones are mainly restricted to citrus fruits [67], and flavanols are found in considerable amounts in tea, apricots, apples, and cherries [66]. 

Labiatae Basil, marjoram, mint, thyme, rosemary, dill, oregano, sage Mono-, diterpenes, flavonoids, rosmarol, ursolic acid, phenolic derivatives... 

Extracts derived from most members of the Labiatae family (Table 3) have the potential to reduce the oxidation of food products and extend shelf life. This antioxidant action is dependent on the ability of the constituent phenolics to scavenge free radicals and chelate metals [27]. This dual effect has implications for CHD since it has been proposed in some studies, mainly from Europe, that a high status of iron increases the risk of CHD [28]. A number of the active compounds found in rosemary have also been found in sage and other herbs. In oregano, four flavonoids were identified among the active fraction [29], while in thyme, dimers of thymol and flavonoids have been isolated and characterized. 

As shown by recent studies, a number of natural extracts from selected herbs (such as rosemary, sage, oregano, and thyme), which were found to be rich in polyphenols, flavonoids, and other compounds, have been well proved to be effective in retarding the development of rancidity in oils and fatty acids. Indeed, the activity of the natural extracts has been found to be dependent, among other factors, on the type and polarity of the extraction solvent, the isolation procedures, and the active components from the raw materials."" ... 

Rosemary (Rosmarinus officinalis) contains flavonoids, phenols, volatile oil and terpenoids. Topical application of rosemary extract, carnosol or ursolic acid to mouse skin inhibited the covalent binding of benzo[a]pyrene to epidermal DNA (Huang et al. 1994), tumour initiation by 7,12-dimethylbenz [ajanthracene (Singletary and Nelshoppen 1991), 12-0-tetradecano)dphorbol-13-acetate-induc-ed tumour promotion, ornithine decarboxylase (EC 4.1.1.17) activity and inflammation. Carnosol showed potent antioxidative activity in a,a-diphe-nyl-P-picrylhydrazyl free radicals scavenge and DNA protection from Fenton reaction (Lo et al. 2002). 

Rosemary is composed of various phenolics such as rosmarinic acid, the flavonoid hesperidin, and the terpenoids camosic acid, camasol, and rosmanol (Al-Sereiti et al. 1999). Rosemary is well known for antioxidant and antimicrobial activity (Naghibi et al. 2005). Multiple extracts and bioactive constituents of rosemary were evaluated for in vitro effect on human cancer cells (Yesil-Celiktas etal. 2010). These included human small cell lung, prostate, liver, breast, and myeloid leukemia, all rosemary extracts and finctionated compounds were toxic to the cell lines at low doses but camosic acid was most effective (Yesil-Celiktas et al. 2010). Bakirel etal. reported in 2007 that ethanol extracts of rosemary reduced blood glucose, and increased insulin levels of rabbits with induced diabetes. They also noted increased levels of the antioxidants SOD and CAT in these animals. 

Sage contains chlorogenic acid as well as many other phenolics and flavonoids seen in basil, oregano, and rosemary (Kintzios 2000). 

Other natural antioxidants - rice bran oil, sesame oil, rosemary extract, flavonoids... 

This chapter will focus on developments in rice bran oil and sesame seed oil, both of which have exceptional oxidative stability and diverse biological activity. In addition, rosemary antioxidants will be described, with an account of methods for extracting bioactive compounds and a discussion of the stability of these compounds in food systems. Recent literature on the stability and health benefits of flavonoids will complete the chapter. 

The antioxidant activity of rosemary has been well documented over the past 50 years. The active constituents include phenolic acids, diterpenes, and flavonoids. Cuppett and HaU (1998), Ho et al. (2000) and Yanishlieva and Heinonen (2(X)1) have completed thorough reviews on rosemary antioxidants, and readers should consult these for additional information. Three prominent compounds - camosic acid, camosol, and rosmarinic acid (Figure 3) - have received the most attention. Camosic acid and camosol account for 1.7-5.5%... 

Cuvelier et al. (1996) assessed the antioxidant activity of 24 pilot-plant and commercial rosemary extracts and identified 22 different compounds for investigation. These included diterpenes, flavonoids, and phenolic acids. There was no apparent correlation between antioxidant activity and extract composition but the most effective extracts contained camosol, rosmarinic acid, and camosic acid and, to a lesser extent, caffeic acid, rosmanol, rosmadial, cirsimaritin, and genkwanin. Camosol was a component of all 24 extracts while rosmarinic and camosic acids were found in 83% and 71% of the extracts, respectively (Cuvelier et al, 1996). Richheimer et al. (1996) also evaluated the antioxidant components in a variety of plant and commercial rosemary products. In the commercial products, camosol and camosic acid were the predominant forms with low levels of methyl camosate. No clear relationship between the type of commercial rosemary extract and antioxidant composition was established. These investigators found that 7-methoxy-rosmanol was present in the commercial extracts but not in extracts obtained... 

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