Effects of Ramie Leaf according to Drying Methods on Antioxidant Activity and Growth Inhibitory Effects of Cancer Cells

Abstract

This study was carried out to discriminate the effects of the ramie leaf according to the drying methods (hot air drying and freeze drying) on antioxidative activity in vitro and antiproliferation in human cancer cells. There were no significant differences in total polyphenol content of ramie leaf ethanol extracts depending on the drying methods, but total flavonoid content was significantly higher in hot air dried ramie leaf (HR) than in freeze dried ramie leaf (FR). The DPPH radical scavenging activity of HR and FR ethanol extracts were found to be 77.74%, and 77.29% in 1000 ppm, respectively. Antioxidative index of HR and FR ethanol extracts measured by Rancimat were lower than those in BHT, BHA, and ascorbic acid, but were higher than that in control. The antiproliferation effect of 80% ethanol extracts of HR and FR on liver cancer cell line (H460), stomach cancer cell line (AGS), and lung cancer cell line (A549) were increased with a dose-dependent manner. The cancer cell growth inhibition activities of HR and FR ethanol extracts at the concentration of 800 μg/mL showed greater than 80% on Hep G2 and A549 cell line, and greater than 75% on AGS cell line. These results suggest that HR and FR ethanol extracts possess potential antioxidative effect and antiproliferation in human cancer cells, and those activities of ramie leaf ethanol extracts depending on the drying methods were similar.

Beneficial role of Boehmeria nivea in health and phytochemical constituents

“…In comparison, BN stem extract revealed lower DPPH radical scavenging activity at the same concentrations and did not show any ABTS radical scavenging effect at the tested concentrations. Previous studies reported BN EtOH leaf extracts as effective antioxidant sources based on DPPH and nitrite radical scavenging activity and reducing power (Kim et al, 2014, 2015). In addition, BN leaf extract showed a higher oxygen radical absorbance capacity (ORAC) value compared to the petiole extract and root extract but lower than the xylem and bud extracts (Wang et al, 2019), suggesting that the antioxidant activity of BN leaf extracts was superior to the BN stem extracts, which may be attributed to the high polyphenol concentrations in leaves (Cho et al, 2017; Lee et al, 2009).…”

“…Nho et al (2010) demonstrated that BN EtOAc leaf extract (250 μg/ml) possessed an anti‐proliferative activity of 67.21% against human colon cancer cells (LoVo) and 56.08% against human lung cancer cells (NCI‐H460). According to Kim et al (2014), 800 μg/ml of ethanol extracts of BN leaf displayed cancer cell growth inhibitory activities of more than 80% on hepatoma (HepG2) and lung cancer (A549) cell lines and over 75% on AGS cells. By contrast, among human malignant melanoma (A375), cervical carcinoma (KB), and HepG2 cell lines, Wang et al (2019) reported that BN petiole and leaf only exhibited inhibitory effects toward HepG2 cells (0.92 ± 0.14 to 1.41 ± 0.07 mg dry weight/ml), and these effects were weaker than the other four parts of the plant examined.…”

Ramie Leaf Extracts Suppresses Adipogenic Differentiation in 3T3-L1 Cells and Pig Preadipocytes

“…Several studies have shown that the antioxidant capacities of natural products depend on the drying method used ( Kim et al, 2007 ; Ferreira and Luthria, 2010 ; Gümü ay et al, 2015 ). Our previous study revealed that both HR and FR extracts had a high 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and high total flavonoid contents ( Kim et al, 2014b ), but that there was no difference between them ( Chen et al, 1997 ). Oxidative stress is caused by an imbalance between pro-oxidants and antioxidants and it plays a critical role in the pathology of various diseases ( Furukawa et al, 2004 ).…”

“…Food preparation methods can affect the nutritional and functional qualities of the food. We have investigated to compare the physicochemical composition and antioxidative properties between HR and FR ( Kim et al, 2014a , b ). There were no significant differences in moisture, crude protein, crude fat, crude ash, and carbohydrate content depending on the drying methods, but the dietary fiber content was significantly higher in FR than in HR.…”

“…Ramie is a rich source of amino acids, vitamins, minerals, dietary fibers, and flavonoids ( Lee et al, 2009 ). Recent studies have shown that the physiochemical composition and the antioxidant properties of ramie vary between hot-air-dried ramie leaf (HR) and freeze-dried ramie leaf (FR) ( Kim et al, 2014a , b ). However, the effect of preparation method on its anti-adipogenic effect has not yet been evaluated.…”