Hazelnut green leafy cover

Alasalvar, C., Karamac, M., Amarowicz, R., and Shahidi, R, Antioxidant and antiradical activities in extracts of hazelnut kernel (Corylus avellana L.) and hazelnut green leafy cover, J. Agric. Food Chem., 54, 4826-4832, 2006. 

Hazelnut kernel (without skin) Hazelnut green leafy cover... 

Five soluble phenolic acids (free and esterifled), one of which is a hydroxylated derivative of benzoic acid (gallic acid) and four are cinnamic acid derivatives (caffeic, p-coumaric, ferulic, and sinapic acids), have been studied and tentatively identified in ethanolic extracts of hazelnut kernel and hazelnut by-products (Table 13.2) [31]. The order of total phenolic acid concentration was as follows hazelnut hard shell > hazelnut green leafy cover > hazelnut tree leaf > hazelnut skin > hazelnut kernel. Different phenolic acids predominate in each plant part examined. Among the identified phenolic acids, p-conmaric acid was most abundant in hazelnut kernel, hazelnut green leafy cover, and hazelnut tree leaf, whereas gallic acid was most abundant in hazelnut skin and hazelnut hard shell, possibly implying the presence and perhaps the dominance of tannins in the latter samples (Table 13.2). The same number, but different concentration, of phenolic acids have also been reported in hazelnnt kernel and hazelnut green leafy cover [30]. 

Hazelnut green leafy cover Hazelnut tree leaf... 

There has been an increased interest in natural antioxidants from plant-derived foods and then-by-products for their role in preventing oxidation of human LDL cholesterol. Table 13.8 shows the inhibition of copper-induced human LDL oxidation by hazelnut extracts. Hazelnut skin and hazelnut green leafy cover extracts at 50 ppm concentration effectively inhibited copper-induced oxidation of... 

Siriwardhana and Shahidi [33] evaluated the Trolox equivalents antioxidant capacity (TEAC) of almond and its by-product extracts and found that ethanolic extracts, at the same concentration the TEAC values, followed the order of brown skin > green shell cover > whole seed (kernel). Values of brown skin and green shell cover extracts were 12.6- and 9.8-fold higher than that of whole seed extract, respectively. Alasalvar et al. [30] observed that hazelnut kernel and its green leafy cover extracts from 80% (v/v) ethanol were characterized as having significantly lower (P < 0.05) total antioxidant activity compared to those of extracts obtained from 80% (v/v) acetone. 

Small amounts of paclitaxel were also isolated from Turkish Tombul hazelnut tree leaf (0.05 J.g/g extract) and hard shell (0.08(tg/g extract). In addition to paclitaxel, 10 deacetyl baccatin III and cephalomannine (leaf and hard shell) and baccatin III (green leafy cover) were found in the extracts (Table 13.10). Taxanes were not detected in the extracts of hazelnut kernel and hazelnut skin from Turkish Tombul cultivar. 

Siriwardhana and Shahidi [33] reported that hydrogen peroxide scavenging activities at lOOppm were 59%, 63%, and 66% and at 200ppm were 86%, 91%, and 91% for whole almond seed, brown skin, and green shell (leafy) cover extracts, respectively. The results obtained from both hazelnut and almond clearly show that extracts from by-products scavenged organic free radicals more effectively than kernel or seed extracts. 

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