Gas chromatographic analysis of capsaicin in Gochujang.

A sensitive, precise, and specific gas chromatographic (GC) method was developed for the analysis of capsaicin in Gochujang and validated by comparing with a column high-performance liquid chromatographic (HPLC) method (AOAC 995.03). The method validation parameters yielded good results, including linearity, precision, accuracy, and recovery. The GC separation was performed on a (5% phenyl)-methylpolysiloxane column [length 30 m, internal diameter (id) 250 microm, film thickness 0.25 microm] followed by flame ionization detection. The conditions of temperature programming were initially 220 degrees C for 1 min, ramp at 5 degrees C/min to 270 degrees C, and hold for 10 min. The recovery of capsaicin in Gochujang was more than 92%, and the detection limit and lower determination limit of the GC analysis were 1.0 and 5.0 microg/g, respectively. The calibration graph for capsaicin was linear from 1 to 250 microg/mL for GC and 0.5 to 50 microg/mL for HPLC. The interday and intraday precisions (relative standard deviations) were <4.02%.

Simultaneous Determination of Piperine, Capsaicin, and Dihydrocapsaicin in Korean Instant-Noodle (Ramyun) Soup Base Using High-Performance Liquid Chromatography with Ultraviolet Detection.

A simultaneous analytical method for piperine, capsaicin, and dihydrocapsaicin in Korean instant-noodle soup base using HPLC was validated in terms of precision, accuracy, sensitivity, and linearity. The HPLC separation was performed on a reversed-phase C18 column (5 µm particle size, 4.6 mm id, 250 mm length) using a UV detector fixed at 280 nm. The LOD and LOQ of the HPLC analyses ranged from 0.25 to 1.03 mg/kg. The intraday and interday precisions of the individual piperine, capsaicin, and dihydrocapsaicin were <10.55%, and the recovery values ranged from 85.43 to 94.68%. The calibration curves exhibited good linearity (r(2) = 0.999) within the tested ranges. These results suggest that the analytical method in this study can be used to classify Korean instant noodles based on their levels of spiciness.

Extraction optimization for obtaining Artemisia capillaris extract with high anti-inflammatory activity in RAW 264.7 macrophage cells.

Plant extracts have been used as herbal medicines to treat a wide variety of human diseases. We used response surface methodology (RSM) to optimize the Artemisia capillaris Thunb. extraction parameters (extraction temperature, extraction time, and ethanol concentration) for obtaining an extract with high anti-inflammatory activity at the cellular level. The optimum ranges for the extraction parameters were predicted by superimposing 4-dimensional response surface plots of the lipopolysaccharide- (LPS-) induced PGE2 and NO production and by cytotoxicity of A. capillaris Thunb. extracts. The ranges of extraction conditions used for determining the optimal conditions were extraction temperatures of 57-65°C, ethanol concentrations of 45-57%, and extraction times of 5.5-6.8 h. On the basis of the results, a model with a central composite design was considered to be accurate and reliable for predicting the anti-inflammation activity of extracts at the cellular level. These approaches can provide a logical starting point for developing novel anti-inflammatory substances from natural products and will be helpful for the full utilization of A. capillaris Thunb. The crude extract obtained can be used in some A. capillaris Thunb.-related health care products.

Anti-inflammatory effects of an ethanolic extract of guava (Psidium guajava L.) leaves in vitro and in vivo.

Plant extracts have been used as a source of medicines for a wide variety of human ailments. Among the numerous traditional medicinal herbs, Psidium guajava L. (Myrtaceae), commonly known as guava, has long been used in folk medicines as a therapeutic agent for the treatment of numerous diseases in East Asian and other countries. The aim of this study was to investigate the anti-inflammatory activity of an ethanolic leaf extract of P. guajava (guava) in vitro and in vivo. Our results demonstrated that guava leaf extract (GLE) significantly inhibited lipopolysaccharide (LPS)-induced production of nitric oxide and prostaglandin E2 in a dose-dependent manner. GLE suppressed the expression and activity of both inducible nitric oxide synthase and cyclooxygenase-2 in part through the downregulation of ERK1/2 activation in RAW264.7 macrophages. Furthermore, GLE exhibited significant anti-inflammatory activity in 2 different animal models-Freund's complete adjuvant-induced hyperalgesia in the rat and LPS-induced endotoxic shock in mice.