Experimental analysis on the main contents of Rhizoma gastrodiae extract and inter-transformation throughout the fermentation process of Grifola frondosa

Research advances in probiotic fermentation of Chinese herbal medicines

Chinese herbal medicines (CHM) have been used to cure diseases for thousands of years. However, the bioactive ingredients of CHM are complex, and some CHM natural products cannot be directly absorbed by humans and animals. Moreover, the contents of most bioactive ingredients in CHM are low, and some natural products are toxic to humans and animals. Fermentation of CHM could enhance CHM bioactivities and decrease the potential toxicities. The compositions and functions of the microorganisms play essential roles in CHM fermentation, which can affect the fermentation metabolites and pharmaceutical activities of the final fermentation products. During CHM fermentation, probiotics not only increase the contents of bioactive natural products, but also are beneficial for the host gut microbiota and immune system. This review summarizes the advantages of fermentation of CHM using probiotics, fermentation techniques, probiotic strains, and future development for CHM fermentation. Cutting-edge microbiome and synthetic biology tools would harness microbial cell factories to produce large amounts of bioactive natural products derived from CHM with low-cost, which would help speed up modern CHM biomanufacturing.

Effects of N6 -(4-hydroxybenzyl) adenine riboside in stress-induced insomnia in rodents

Adenosine exhibits a somnogenic effect; however, there is no adenosinergic hypnotic because of cardiovascular effects. This study investigated whether N6-(4-hydroxybenzyl) adenine riboside (T1-11), extracted from Gastrodia elata, produces somnogenic effects in rodents. We determined the involvement of adenosine 2A receptors (A2ARs) in GABAergic neurons of the ventrolateral preoptic area (VLPO) and the cardiovascular effects. Change of cage bedding is employed as a stressor to induce insomnia in rodents, and electroencephalograms and electromyograms were used to acquire and analyse sleep-wake activity. We found that intracerebroventricular administration of T1-11 before a dark period increased non-rapid eye movement (NREM) and rapid eye movement (REM) sleep during a dark period, and T1-11-induced sleep increases were blocked by the A2AR antagonist, SCH58261, in naïve rats. Oral administration of T1-11 increased NREM sleep during both dark and light periods. Microinjection of the A2AR antagonist, SCH58261, into the VLPO blocked sleep effects of T1-11. In addition to the somnogenic effect in naïve mice, T1-11 suppressed the stress-induced insomnia and this suppressive effect was blocked by SCH58261. C-fos expression in GABAergic neurons of VLPO was increased after administration of T1-11 in Gad2-Cre::Ai14 mice, suggesting the activation of GABAergic neurons in the VLPO. T1-11 exhibited no effects on heart rate and the low frequency/high frequency ratio of heart rate variability. We concluded that T1-11 elicited somnogenic effects and effectively ameliorated acute stress-induced insomnia. The somnogenic effect is mediated by A2ARs to activate GABAergic neurons in the VLPO. This adenosine analogue could be a potential hypnotic because of no sympathetic and parasympathetic effects on the cardiovascular system.

The Application of Fermentation Technology in Traditional Chinese Medicine: A Review

In Chinese medicine, fermentation is a highly important processing technology whereby medicinal herbs are fermented under appropriate temperature, humidity, and moisture conditions by means of the action of microorganisms to enhance their original characteristics and/or produce new effects. This expands the scope of such medicines and helps them to meet the stringent demands of clinical application. Since ancient times, Chinese medicine has been made into Yaoqu to reduce its toxicity and increase its efficiency. Modern fermentation technologies have been developed on the basis of traditional fermentation techniques and modern biological technology, and they can be divided into solid fermentation, liquid fermentation, and two-way fermentation technologies according to the fermentation form employed. This review serves as an introduction to traditional fermentation technology and its related products, modern fermentation technologies, and the application of fermentation technology in the field of Chinese medicine. Several problems and challenges facing the field are also briefly discussed.

Comparison of Bioactive Compounds and Antioxidant Activities of Maclura tricuspidata Fruit Extracts at Different Maturity Stages

Maclura tricuspidata fruit contains various bioactive compounds and has traditionally been used in folk medicine and as valuable food material in Korea. The composition and contents of bioactive compounds in the fruit can be influenced by its maturity stages. In this study, total phenol, total flavonoid, individual polyphenolic compounds, total carotenoids and antioxidant activities at four maturity stages of the fruit were determined. Polyphenolic compounds were analyzed using high-pressure liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS) and HPLC. Among 18 polyphenolic compounds identified in this study, five parishin derivatives (gastrodin, parishin A, B, C, E) were positively identified for the first time in this plant. These compounds were also validated and quantified using authentic standards. Parishin A was the most abundant component, followed by chlorogenic acid, gastrodin, eriodictyol glucoside, parishin C, parishin E and parishin B. The contents of all the polyphenolic compounds were higher at the immature and premature stages than at fully mature and overmature stages, while total carotenoid was found to be higher in the mature and overmature stages. Overall antioxidant activities by three different assays (DPPH, ABTS, FRAP) decreased as maturation progressed. Antioxidant properties of the fruit extract are suggested to be attributed to the polyphenols.

Relative tissue distribution and excretion studies of gastrodin and parishin from powder and extract of Gastrodiae Rhizoma in rat by UHPLC-ESI-MS/MS

New research has indicated that Gastrodiae Rhizome (GR) has potential anti-diabetic and anti-asthmatic effects in mouse models. On the basis of our previous study of the relative bioavailability of gastrodin (GAS) and parishin (PA) from extract and powder of GR, we performed further research on the tissue distribution and excretion of the two analytes. A reliable bioanalytical method for the quantification of GAS and PA in rat tissues and excretion is required. Chromatographic separation was carried out on a gradient mobile phase of acetonitrile-water with 0.1% formic acid. Calibration curves (1/x² weighted) offered satisfactory linearity (r²  > 0.9835) within 100-3000 ng mL^-1 for GAS and (r²  > 0.9862) within 10-1000 ng mL^-1 for PA. The relative standard deviations of the intra-day and inter-day precision were all <14.98%, whilst the relative errors of the intra-day and inter-day accuracy were all within ±14.71%. The matrix effect and recovery values were satisfactory in all of the biological matrices examination. The data of relative differences in tissue distribution and excretion of GAS and PA from powder and extract of GR indicated that higher bioavailabilities for GAS and PA were obtained when a dosage of 4 g kg^-1 GR powder was used.

Relative bioavailability of gastrodin and parishin from extract and powder of Gastrodiae rhizoma in rat

A rapid, sensitive and reliable UHPLC-ESI-MS/MS method was developed for simultaneous determination of gastrodin and parishin in rat plasma. The LLOQ of the two analytes were 1.00×10(-1) and 8.30×10(-5)μg/mL, respectively. The intra-day and inter-day precision were all less than 10% of the relative standard deviation (RSD), whilst the accuracy were all within ±15% of the relative error (RE). The proposed method was successfully applied for pharmacokinetics study on the two analytes in rats after oral administration of Gastrodiae rhizoma (GR) extract and powder at low, medium and high dosages. Blood samples were collected from the suborbital vein at predetermined time points and were precipitated using methanol. Chromatographic separations were carried out on a Kinetex XB-C18 column (2.1mm×150mm, 1.7μm) with a gradient mobile phase of acetonitrile-water with 0.1% formic acid as a modifier. The pharmacokinetic parameters of the two analytes in rats were obtained and the relative bioavailability of gastrodin and parishin in two formulations were calculated. The results indicated that higher bioavailability was obtained when low dosage of GR powder was used, whereas, higher bioavailability values were obtained when medium and high dosages of GR extract were used.