Rooibos tea

Bramati, L. et al.. Quantitative characterization of flavonoid compounds in Rooibos tea (Aspa-lathus linearis) by LC-UV/DAD, J. Agric. Food Chem., 50, 5513, 2002. 

The dihydrochalcones aspalathin and nothofagin have been identified as the main flavonoids in the South-African Rooibos tea (Aspalathus linearis) [41]. 

Figure 1.17 Hydroxychalcones occurring in unfermented rooibos tea and flavanone...

Joubert E, Ferreira D. 1996. Antioxidants of rooibos tea—a possible explanation for its health promoting properties SA J Food Sci Nutr 8 79-83. 

Krafczyk N, Glomb MA. 2008. Characterization of phenolic compounds in rooibos tea. J Agric Food Chem 56 3368-3376. 

Gilani AH, Khan AU, Ghayur MN, Ali SF, Herzig JW. 2006. Antispasmodic effects of Rooibos tea (Aspalathus linearis) is mediated predominantly through K + -channel activation. Basic Clin Pharmacol Toxicol 99 365-373. 

In the food industry, these natural products have now been classified under a new class of food called nutraceuticals or functional foods, because these products provide a health benefit beyond basic nutrition 22, 23). According to Wilkinson 24), most of the nutraceuticals used in the food industry are plant derived. Further, Addae-Mensah (25), showed that the world trade in medicinal plants accounts for about 30% of the total dmg market and was estimated excluding plants used as raw material sources for the essential oils required to manufacture cosmetics, food additives and other non-medicinal purposes. The increased recogiution of the value of natural products in the pharmaceutical, neutraceutical, cosmetic and other industries have created a huge demand for raw natural products. By taking Rooibos tea as an example from South Africa, Wilson 26) in detail describes the demand for Rooibos from different countries. However, for many natural products estimation of the actual demand is very difficult and the data sparse given the diversity of natural products used across industries and production variation within and across countries and the lack of... 

However, a source of the non-natural 9S isomer (2) was first required. The ready availability of natural crinitol made a racemization/resolution route, as illustrated in Scheme 1, attractive. Racemization was accomplished by Collins oxidation (16,25) to the dicarbonyl compound (14), followed by lithium aluminum hydride (LAH) reduction to give the racemic mixture (1 + 2). Resolution via diastereomeric derivatives seemed plausible. Esterification with enantiomerically pure a-methoxy-a-(trifluoromethyl) phenylacetic acid (MTPA) (17), followed by separation of diastereomers by recycle-HPLC (R-HPLC), had earlier been used to purify enantiomers of ipsenol and ipsdienol (26). A model system, the resolution of -3-nonen-2-ol, a secondary allylic alcohol naturally occurring in Rooibos tea (16,27), also worked satisfactorily. Therefore, the route using the bis-(MTPA) esters was selected for crinitol. 

M. Kawakami, A. Kobayashi and K. Katoh, Volatile constituents of Rooibos tea (Aspalathus linearis) as affected by extraction process, J. Agric. Food Chem., 41 (1993) 633-636. 

Nakano, M. Anti-HIV Activity of Alkaline Extracts of Rooibos Tea Leaves. Aromatopia. 1997,24, 28-30. 

Kawano A, Nakamura H, Hata S, Minakawa M, Miura Y, Yagasaki K (2009) Hypoglycemic effect of aspalathin, a rooibos tea component from Aspalaihus linearis, in type 2 diabetic model db/db mice. Phytomedicine 16 437... 

Rooibos tea from Aspalathus linearis 4 flavones, 8 flavonols, 2 dihydrochalcones SLE (boiled, water) Phenomenex Luna Phenyl-Hexyl (250 X 4.6 mm, 5 pm) Graditmt 2 % acetic acid (aq.) and MeCN DAD [123]... 

Rooibos tea Aspalathus linearis) Chronic 21 mo Drinking water Rat Normal aging Reduced TBA reactive substance formation in frontal cortex, occipital cortex, hippocanqrus, and cerebellum [134]... 

Inanami O, Asanuma T, Inukai N, Jin T, Shimokawa S, Kasai N, Nakano M, Sato F, Kuwabara M. The suppression of age-related accumulation of lipid peroxides in rat brain by administration of Rooibos tea (Aspalathus linearis). Neurosci Lett 1995 196 85-88. 

---