Method validation and measurement uncertainty for the simultaneous determination of synthetic phenolic antioxidants in edible oils commonly consumed in Korea.

This study investigated a method for the validation and determination of measurement uncertainty for the simultaneous determination of synthetic phenolic antioxidants (SPAs) such as propyl gallate (PG), octyl gallate (OG), dodecyl gallate (DG), 2,4,5-trihydroxy butyrophenone (THBP), tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) in edible oils commonly consumed in Korea. The validated method was able to extract SPA residues under the optimized HPLC-UV and LC-MS/MS conditions. Furthermore, the measurement of uncertainty was evaluated based on the precision study. For HPLC-UV analysis, the recoveries of SPAs ranged from 91.4% to 115.9% with relative standard deviations between 0.3% and 11.4%. In addition, the expanded uncertainties of the SPAs ranged from 0.15 to 5.91. These results indicate that the validated method is appropriate for the extraction and determination of SPAs and can be used to verify the safety of edible oil products containing SPAs residues.

Acute and subchronic (13-week) toxicity of fermented Acanthopanax koreanum extracts in Sprague Dawley rats.

The biological fermentation of plants is usually used to improve their product properties, including their biological activity. Acanthopanax koreanum is a plant indigenous to Jeju, Korea; however, fermented A. koreanum (FAK) has not been guaranteed to be safe. Therefore, in this study, a safety evaluation of aqueous extracts of FAK was performed using Sprague Dawley rats. The acute toxicity of FAK did not influence animal mortality, body weight changes or the animals' clinical appearance at a concentration of 5000 mg/kg body weight. Using doses of 500, 1000 and 2000 mg/kg/day in a subchronic (13-week) toxicity study, the administration of FAK in male rats increased their body weight, food consumption, absolute liver weight, liver-associated enzymes and total cholesterol content. However, these effects of FAK were not considered toxic because the changes were not accompanied by any evidence of clinical signs or any change in the histopathological examination. On the other hand, the FAK-treated female rats did not exhibit significant changes in their body weight, food consumption, absolute and relative organ weights or liver enzymes. These results suggest that the acute oral administration of FAK is non-toxic to rats, and 13 weeks of repeated dosing demonstrated no FAK-related toxicity at a concentration of 2000 mg/kg. Therefore, the no-observed-adverse-effect level (NOAEL) of FAK was determined to be 2000 mg/kg/day for both male and female rats.

The antioxidant activity and their major antioxidant compounds from Acanthopanax senticosus and A. koreanum.

The antioxidant activity and chlorogenic acid and caffeic acid contents were investigated from different parts of Acanthopanax senticosus and A. koreanum. Antioxidant activity was assessed by various in vitro assays such as DPPH, ABTS, FRAP, reducing power assays and ORAC, and the chlorogenic acid and caffeic acid were validated by HPLC chromatography. Among the various extracts, the fruit extracts of A. senticosus and A. koreanum exhibited strongest antioxidant activities including ABTS, FRAP, reducing power and ORAC, however, strongest DPPH radical scavenging activity was observed from the leaf extract of A. senticosus. In addition, the antioxidant activities of various extracts were correlated with total phenolic and proanthocyanidin contents. The major phenolic contents from various parts of these plants observed that leaf extract of A. senticosus expressed higher levels of chlorogenic acid (14.86 mg/dry weigh g) and caffeic acid (3.09 mg/dry weigh g) than other parts. Therefore, these results suggest that the leaf of A. senticosus may be an excellent natural source for functional foods and pharmaceutical agents, and the validated method was useful for the quality control of A. senticosus.

Acute and subchronic (28 days) oral toxicity studies of Codonopsis lanceolata extract in Sprague-Dawley rats.

Codonopsis lanceolata is a perennial plant that has been used as a food and in traditional medicine for the treatment of cough, bronchitis, and inflammation in East Asia including Korea, Japan, and China. However, information regarding its toxicity is limited. Therefore, we performed a safety evaluation of aqueous C. lanceolata root extract (CLE) in Sprague-Dawley rats. Assessment of acute toxicity revealed that CLE did not influence mortality, clinical appearance, body weight gain, or necropsy findings at a dose of 5000 mg/kg body weight. In the subchronic oral toxicity, data revealed that several significant alteration in food consumption, water consumption, protein excretion, WBCs levels, TGs, BUN levels, and the absolute and relative weights in the liver, spleen and lungs. However, these changes were transient and were not considered treatment related because they showed no apparent dose dependent. These results suggest that CLE (1250, 2500, and 5000 mg/kg body weight/day) administered orally does not cause acute or subchronic toxicity to male or female rats. The 50% lethal dose (LD50) of CLE was determined to be greater than 5000 mg/kg.

Codonopsis lanceolata extract prevents diet-induced obesity in C57BL/6 mice.

Codonopsis lanceolata extract (CLE) has been used in traditional medicine in the Asian-Pacific region for the treatment of bronchitis, cough, and inflammation. However, it is still unclear whether obesity in mice can be altered by diet supplementation with CLE. To investigate whether CLE could have preventative effects on high fat diet (HFD)-induced obesity, male C57BL/6 mice were placed on either a normal chow diet, 60% HFD, or a HFD supplemented with CLE (60, 180, and 360 mg/kg/day) for 12 weeks. CLE decreased body weight and subcutaneous and visceral fat weights in HFD-induced obese mice. CLE group mice showed lower fat accumulation and a smaller adipocyte area in the adipose tissue compared with the HFD group mice. CLE group mice exhibited lower serum levels of triglycerides, total cholesterol, low density lipoprotein (LDL), glucose, and insulin compared with the HFD group mice. In addition, CLE decreased liver weight and lowered the increase in aspartate aminotransferase (AST) and alanine transaminase (ALT) levels in HFD-induced obese mice. These results indicate that CLE can inhibit the development of diet-induced obesity and hyperlipidemia in C57BL/6 mice.