Cudrania tricuspidata Bureau (Moraceae) shows numerous pharmacological effects and has been used in traditional herbal remedies for inflammation, gastritis, tumors, and liver diseases. However, no validated analytical method for the standardization and optimization of the biological properties of C. tricuspidata preparations has been reported. We developed and validated a reverse-phase high-performance liquid chromatography (HPLC) method for the separation and quantification of active markers. Ethanolic extracts of C. tricuspidata leaves were prepared and evaluated for chemical profiles and biological activities. The 80% ethanolic extract demonstrated the greatest antioxidant activity and phenolic content, while the 100% ethanolic extract had the greatest total flavonoid content and xanthine oxidase (XO) inhibitory activity. The validated HPLC method confirmed that chlorogenic acid, rutin, and kaempferol were present in C. tricuspidata leaf extracts. We postulated that the antioxidant and anti-hyperuricemic/gout effects of C. tricuspidata extract could be attributed to these marker compounds. Our results suggested that the flavonoid-rich fraction of the leaf extract may be utilized for the treatment and prevention of hyperuricemia-related diseases, and the validated method and marker compounds could be applied for the quality control of C. tricuspidata preparations.

Dendropanax morbifera Leveille (Araliaceae) has been used in traditional oriental remedies for cancer, inflammation, diabetes, and thrombosis. However, a validated analytical method, standardization, and optimization of extraction conditions with respect to biological activity have not been reported. In this study, a simple and validated HPLC method for identifying and quantifying active substances in D. morbifera was developed. Hot water and ethanolic D. morbifera leaf extracts from different production regions were prepared and evaluated with regard to their chemical compositions and biological activities. The contents of active compounds such as rutin and chlorogenic acid were determined in four samples collected from different regions. The 80% ethanolic extract showed the best antioxidant activity, phenolic content, reducing power, and xanthine oxidase (XO) inhibitory activity. The validated HPLC method confirmed the presence of chlorogenic acid and rutin in D. morbifera leaf extracts. The antioxidant and XO inhibitory activity of D. morbifera extract could be attributed to the marker compounds. Collectively, these results suggest that D. morbifera leaves could be beneficial for the treatment or prevention of hyperuricemia-related disease, and the validated HPLC method could be a useful tool for the quality control of food or drug formulations containing D. morbifera.

Cudrania tricuspidata Bureau (Moraceae) (CT) is a dietary and medicinal plant distributed widely in Northeast Asia. There have been no studies on the effect of CT and/or its active constituents on in vivo xanthine oxidase (XO) activity, hyperuricemia, and gout. The aim of this study was to investigate XO inhibitory and antihyperuricemic effects of the ethanol extract of CT leaf (CTLE) and its active constituents in vitro and in vivo. Gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC) analyses were used to determine a chemical profile of CTLE. XO inhibitory and antihyperuricemic effects of CTLE given orally (30 and 100 mg/kg per day for 1 week) were examined in potassium oxonate-induced hyperuricemic ICR mice. CTLE exhibited XO inhibitory activity in vitro with an IC50 of 368.2 μg/mL, significantly reduced serum uric acid levels by approximately 2-fold (7.9 nM in normal mice; 3.8 nM in 30 mg/kg CTLE; 3.9 nM in 100 mg/kg CTLE), and significantly alleviated hyperuricemia by reducing hepatic (by 39.1 and 41.8% in 30 and 100 mg/kg, respectively) and serum XO activity (by 30.7 and 50.1% in 30 and 100 mg/kg, respectively) in hyperuricemic mice. Moreover, several XO inhibitory and/or antihyperuricemic phytochemicals, such as stigmasterol, β-sitosterol, vitamin E, rutin, and kaempferol, were identified from CTLE. Compared with rutin, kaempferol showed markedly higher XO inhibitory activity in vitro. Our present results demonstrate that CTLE may offer a promising alternative to allopurinol for the treatment of hyperuricemia and gout.

Dendropanax morbifera H. Levis a medicinal plant native to South Korea, East Asia, and South America. Among some 75 species, one species grows in Korea. In previous studies, D. morbifera extracts with anti-oxidant, anti-inflammatory, anti-complementary and anti-cancer activities were reported. The present study aims to investigate optimization of extraction and evaluation of anti-hyperuricemic effects of D. morbifera leaf and the phytochemicals contained therein. Ethanol and hexane extract were found to display the best xanthine oxidase inhibition among six types of solvent and water extract. The antioxidant effect of the ethanol extract was superior to that of the hexane extract. The DPPH radical scavenging effect of the ethanol and hexane extracts were 81.52 ± 1.57% and 2.69 ± 0.16. The reducing power of the ethanol and hexane extracts were 9.71 ± 0.15 and 0.89 ± 0.01 mg/g equivalent of gallic acid. Total phenols of the ethanol and hexane extracts were 6.53 ± 0.16 and 0.63 ± 0.001 mg/g equivalent of gallic acid. In addition, we compared the two marker compounds from D. morbifera, chlorogenic acid and rutin, which were determined in the ethanol extract at 0.80 ± 0.03% and 0.52 ± 0.01%, respectively. We found that the ethanol extracts showed better xanthine oxidase inhibition than hexane extracts. Especially, ethanol extracts showed higher antioxidant activity than hexane extracts. Based on these results, we selected the ethanol extract as an effective xanthine oxidase inhibitor and confirmed whether ethanol extracts showed xanthine oxidase inhibition in animal experiments. The in vivo mouse study demonstrated that ethanol extract of D. morbifera leaf at the dose of 300 mg/kg could inhibit blood/hepatic xanthine oxidase activity and this result shows that the xanthine oxidase inhibitory activity in vitro is reproduced in vivo. The present study showed that ethanol extract was optimal xanthine oxidase inhibitor which can be applied to prevent diseases related to hyperuricemia.

We evaluated the antioxidant and antibacterial activity of hexnane, ethyl acetate, acetone, methanol, ethanol, and water extracts of the Quercus acuta leaf. The antioxidant properties were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, reducing power, and total phenolic content. Antibacterial activity was assessed against general infectious pathogens, including antibiotic-resistant clinical isolates. The methanolic extract showed the highest DPPH radical scavenging activity and total phenolic content, while the reducing power was the highest in the water extract. The ethyl acetate extract showed the best antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) strains. Additionally, it displayed antibacterial activity against Staphylococcus aureus KCTC1928, Micrococcus luteus ATCC 9341, Salmonella typhimurium KCTC 1925, Escherichia coli KCTC 1923, and eight MRSA strains. These results present basic information for the possible uses of the ethanolic and ethyl acetate extracts from Q. acuta leaf in the treatment of diseases that are caused by oxidative imbalance and antibiotic-resistant bacterial infections. Six active compounds, including vitamin E, which are known to possess antioxidant and antibacterial activity, were identified from the extracts. To the best of our knowledge, this is the first study that reports the chemical profiling and antibacterial effects of the various QA leaf extracts, suggesting their potential use in food therapy or alternative medicine.