Antioxidant Properties of Du-zhong (Eucommia ulmoides Oliv.) Extracts and Their Effects on Color Stability and Lipid Oxidation of Raw Pork Patties

Abstract

The ethanol extracts from leaf, roasted cortex, and seed of Du-zhong ( Eucommia ulmoides Oliv.) were examined for total phenolics content (TPC) and total flavonoids content (TFC). The antioxidant activity of the extracts was evaluated by measuring the radical scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and lipid peroxidation inhibition capacity in a beta-carotene/linoleic acid system. Du-zhong leaf extract was found to have the highest TPC content (94.46 +/- 1.17 mg of gallic acid equiv/g of solid extract) and TFC content (61.36 +/- 0.59 mg of catechin equiv/g of solid extract). In the above three antioxidant assay systems, Du-zhong leaf extract also exhibited the strongest antioxidant capacities, followed by roasted cortex extract and seed extract. The effects of Du-zhong extracts (leaf, roasted cortex, and seed) on lipid oxidation, meat color, and metmyoglobin (MetMb) formation in raw pork patties were investigated and compared with that of butylated hydroxytoluene (BHT) during refrigerated storage at 4 degrees C for 8 days. The results indicated that the addition of leaf extract at 0.1% (w/w), roasted cortex extract at 0.1% (w/w), and BHT at 0.01% (w/w) decreased day 8 TBARS values by 35, 20, and 37%, respectively. Du-zhong leaf extract at 0.1% (w/w) also exhibited a certain stabilizing effect on meat redness a* value and retarded the formation of MetMb. This study suggests that Du-zhong leaf extract may be a potential source of natural antioxidants.

Eucommia ulmoides Oliv. Bark. protects against hydrogen peroxide-induced neuronal cell death in SH-SY5Y cells

“…Based on previous study, we hypothesized that EUE may attenuate the learning and memory impairments induced by Ab 25-35 by an antioxidant mechanism. In fact, previous studies have shown directly that EUE inhibits oxidative stress Lee et al, 2005;Xu et al, 2010;Hsieh, 2000, 2003). Because evidence suggests that oxidative stress contributes to the perturbation of calcium homeostasis and subsequent apoptosis observed in AD patients (Annunziato et al, 2003;Joseph et al, 1997;Yu et al, 2001).…”

Phenolic composition and antioxidant activity of culms and sugarcane (Saccharum officinarum L.) products

“…Often no correlation is observed between results by RSA and b-CLAM (Tsao, Yang, Xie, Sockovie, & Khanizadeh, 2005). RAS is more selective toward hydrophilic compounds, while b-CLAM reflects contents of lipophilic substances (Sahreen, Khan, & Khan, 2010;Xu, Tang, Liu, Li, & Dai, 2010). For these reasons, conclusions based only on one method may lead to underestimation of antioxidant activities.…”

Chlorogenic Acid Prevents Osteoporosis by Shp2/PI3K/Akt Pathway in Ovariectomized Rats

“…Polyphenolic compounds from the Chinese herb du-zhong ( Eucommia ulmoides Oliver ) exhibit osteoprotective activity as well as antioxidative effects[28–30]. Du-zhong extract can inhibit lipid peroxidation and oxidative damage in biomolecules[31–34]. Good correlation was observed between the polyphenolic content and antioxidant activity level of du-zhong extracts[35].…”