Peter Hoi-Fu Yu

A review of the pharmacological effects of Arctium lappa (burdock).

Arctium lappa, commonly known as burdock, is being promoted/recommended as a healthy and nutritive food in Chinese societies. Burdock has been used therapeutically in Europe, North America and Asia for hundreds of years. The roots, seeds and leaves of burdock have been investigated in view of its popular uses in traditional Chinese medicine (TCM). In this review, the reported therapeutic effects of the active compounds present in the different botanical parts of burdock are summarized. In the root, the active ingredients have been found to “detoxify” blood in terms of TCM and promote blood circulation to the skin surface, improving the skin quality/texture and curing skin diseases like eczema. Antioxidants and antidiabetic compounds have also been found in the root. In the seeds, some active compounds possess anti-inflammatory effects and potent inhibitory effects on the growth of tumors such as pancreatic carcinoma. In the leaf extract, the active compounds isolated can inhibit the growth of micro-organisms in the oral cavity. The medicinal uses of burdock in treating chronic diseases such as cancers, diabetes and AIDS have been reported. However, it is also essential to be aware of the side effects of burdock including contact dermatitis and other allergic/inflammatory responses that might be evoked by burdock.

Chlorogenic Acid Exhibits Cholesterol Lowering and Fatty Liver Attenuating Properties by Up‐regulating the Gene Expression of PPAR‐α in Hypercholesterolemic Rats Induced with a High‐Cholesterol Diet

Hypercholesterolemia is a major risk factor for the development of cardiovascular disease and nonalcoholic fatty liver disease. Natural compounds have been proved to be useful in lowering serum cholesterol to slow down the progression of cardiovascular disease and nonalcoholic fatty liver disease. In the present study, the hypocholesterolemic and hepatoprotective effects of the dietary consumption of chlorogenic acid were investigated by monitoring plasma lipid profile (total cholesterol, triglycerides, high‐density lipoprotein and low‐density lipoprotein) in Sprague–Dawley rats fed with a normal diet, a high‐cholesterol diet or a high‐cholesterol diet supplemented with chlorogenic acid (1 or 10 mg/kg/day p.o.) for 28 days. Chlorogenic acid markedly altered the increased plasma total cholesterol and low‐density lipoprotein but decreased high‐density lipoprotein induced by a hypercholesterolemic diet with a dose‐dependent improvement on both atherogenic index and cardiac risk factor. Lipid depositions in liver were attenuated significantly in hypercholesterolemic animals supplemented with chlorogenic acid. It is postulated that hypocholesterolemic effect is the primary beneficial effect given by chlorogenic acid, which leads to other secondary beneficial effects such as atheroscleroprotective, cardioprotective and hepatoprotective functions. The hypocholesterolemic functions of chlorogenic acid are probably due to the increase in fatty acids unitization in liver via the up‐regulation of peroxisome proliferation‐activated receptor α mRNA. Copyright

A review of the anticancer and immunomodulatory effects of Lycium barbarum fruit

The anticancer effects of traditional Chinese medicine (TCM) have attracted the attention of the public vis-à-vis existing cancer therapies with various side effects. Lycium barbarum fruit, commonly known as Gou Qi Zi in China, is a potential anticancer agent/adjuvant. Its major active ingredients, L. barbarum polysaccharides (LBP), scopoletin and 2-O-β-d-glucopyranosyl-l-ascorbic acid (AA-2βG), are found to have apoptotic and antiproliferative effects on cancer cell lines. Moreover, LBP also contributes to body’s immunomodulatory effects and enhances effects of other cancer therapies. It is not known whether there are any undesirable effects. Further studies on its pharmacological mechanisms and toxicology could facilitate a safe usage of this TCM herb.

Antioxidative activities and the total phenolic contents of tonic Chinese medicinal herbs.

Abstract.Chinese medicated diet is an everyday practice in China. In this study, 16 commonly used soup making tonic Chinese medicinal herbs were selected for antioxidative capacities by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP), and the total phenolic contents of these herbal extracts were measured by the Folin-Ciocalteu method. It confirmed that drinking tonic soups could supplement total antioxidants intake. Amongst the tested herbal extracts, extracts of Canarium album Raeusch., Flos caryophylli and Fructus amomi were found to have the highest antioxidative activities in both DPPH and FRAP assays. Their antioxidative activities were comparable to ascorbic acid and butylated hydroxytoluene. Thus, these herbs are safe and inexpensive sources of natural antioxidants. A significant relationship between the antioxidative effects and total phenolic contents were found, indicating phenolic compounds are the major contributor of antioxidative capacities of these herbs. In addition, a strong correlation between DPPH assay and FRAP assay implied that antioxidants in these herbs were capable of scavenging free radicals and reducing oxidants.

Water extract of Rheum officinale Baill. induces apoptosis in human lung adenocarcinoma A549 and human breast cancer MCF-7 cell lines

ETHNOPHARMACOLOGICAL RELEVANCE Rheum officinale Baill. (Da Huang) is one of the herbs commonly used in traditional Chinese medicine formulae against cancer. The traditional decoction is similar to the water extract used in the present study. AIM OF THE STUDY The water extract of Da Huang was investigated to see if it possesses anticancer effects through apoptotic pathways. MATERIALS AND METHODS Human lung adenocarcinoma A549 and human breast cancer MCF-7 cell lines were treated with different concentrations of Da Huang water extract at different time intervals. Growth inhibition was detected by MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] and colony formation assays; apoptosis was detected by cell morphologic analysis, DNA fragmentation analysis and COMET assay. RESULTS Da Huang water extract was found to have significant growth inhibitory effects on both A549 and MCF-7 cell lines with IC(50) values 620+/-12.7 and 515+/-10.1 microg/ml, respectively. Growth inhibitory effects were dose- and time-dependent. A significant decrease in cell number, DNA fragmentation and single DNA strand breakages were observed in the Da Huang water extract treated A549 and MCF-7 cells. CONCLUSIONS This suggests that the water extract of Da Huang exerts potential anticancer activity through growth inhibition and apoptosis on MCF-7 and A549 cells lines.

In vitro cytotoxicity, hemolysis assay, and biodegradation behavior of biodegradable poly(3‐hydroxybutyrate)–poly(ethylene glycol)–poly(3‐hydroxybutyrate) nanoparticles as potential drug carriers

Nanoparticles based on amorphous poly(3-hydroxybutyrate)-poly(ethylene glycol)-poly(3-hydroxybutyrate) (PHB-PEG-PHB) are potential drug delivery vehicles, and so their cytotoxicity and hemolysis assay were investigated in vitro using two kinds of animal cells. The PHB-PEG-PHB nanoparticles showed excellent biocompatibility and had no cytotoxicity on animal cells, even when the concentrations of the PHB-PEG-PHB nanoparticle dispersions were increased to 120 microg/mL. Moreover, no hemolysis was detected with the PHB-PEG-PHB nanoparticles, suggesting that the PHB-PEG-PHB nanoparticles were obviously much hemocompatible for drug delivery applications. In the presence of intracellular enzyme esterase, the biocompatible PHB-PEG-PHB nanoparticles might be hydrolyzed, and their biodegradable behavior was monitored by the fluorescence spectrum and the pH meter. The initial biodegradation rate of the PHB-PEG-PHB nanoparticles was closely related to the enzymatic amount and the PHB block length. Compared with that obtained from the fluorescence determination, the initial biodegradation rate from pH measurement was faster. The biodegraded products mainly consisted of 3HB monomer and dimer, which were the metabolites present in the body.

Responses of an anaerobic fixed-film reactor to hydraulic shock loadings

The responses of an anaerobic fixed-film reactor (AFFR) to hydraulic shock loadings were studied. The AFFR was started up with a synthetic wastewater of 3000 mg COD/l at 5.00 d hydraulic retention time (HRT), achieving 98.1% COD removal efficiency. When stable operation was attained, the HRT was sporadically adjusted to 2.50, 1.25, 1.00 and 0.50 d to simulate two, four, five and 10 times hydraulic shock loadings, respectively, while the COD loading was maintained constant. Under two, four and five times hydraulic shock loadings, the COD removal efficiency was temporarily reduced to between 84.4 and 88.3%, and the pH of the treated effluent and the biogas production were also affected. The AFFR could recover from the temporary inhibition due to these shock loadings and resumed normal operation within eight days. On the other hand, under 10 times hydraulic shock loading, the treatment performance deteriorated drastically. Volatile fatty acids (VFAs) accumulated in the AFFR liquor, resulting in reactor souring and failure. When the HRT was returned to 5.00 d, the biofilter could be recovered within a few days. The ability of the AFFR to recover from critical hydraulic shock loadings and system failure was attributed to the immobilized-biofilm design, which enabled the temporarily inhibited biofilms to be retained in the AFFR and regain activity when favourable conditions were restored.

Correlation Between Antioxidative Power and Anticancer Activity in Herbs from Traditional Chinese Medicine Formulae with Anticancer Therapeutic Effect

Abstract Lobeliae chinensis. Herba (“ban bian lian”), Rheum officinale. Baill. (“da huang”), Sanguisorba officinalis. Linn. (“di yu”), Agrimonia pilosa. Ledeb. (“xian he cao”), and Paris polyphylla. Smith (“zhi hua tou”) are well-known traditional Chinese medicines. They are commonly used in traditional Chinese medicine formulae against cancer. In this study, the antioxidant and anticancer effects of water extracts of these herbs were investigated. In the antioxidant and anticancer studies, water extracts of di yu, xian he cao, and da huang were show to be the most antioxidative and had the highest growth inhibitory effect on human lung adenocarcinoma A549 cell and human breast cancer MCF-7 cell. By comparing their percentage free radical scavenging capacity (SR%) and percentage growth inhibition on A549 and MCF-7 cells, a positive linear relationship between antioxidant activity and anticancer effect of the five herbal water extracts was found. This suggested that the antioxidants of the herbal water extracts might contribute to their anticancer effects on A549 and MCF-7 cells.

Accumulation of biopolymers in activated sludge biomass.

In this study, activated sludge bacteria from a conventional wastewater treatment process were induced to accumulate polyhydroxyalkanoates (PHAs) under different carbon-nitrogen (C:N) ratios. As the C:N ratio increased from 20 to 140, specific polymer yield increased to a maximum of 0.38 g of polymer/g of dry cell mass while specific growth yield decreased. The highest overall polymer production yield of 0.11 g of polymer/g of carbonaceous substrate consumed was achieved using a C:N ratio of 100. Moreover, the composition of polymer accumulated was dependent on the valeric acid content in the feed. Copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] was produced in the presence of valeric acid. The 3-hydroxyvalerate (3HV) mole fraction in the copolymer was linearly related to valeric content in the feed, which reached a maximum of 54% when valeric acid was used as sole carbon source. When the 3HV U in the polymer increased from 0-54 mol%, the melting temperature decreased from 178 degrees to 99 degrees C. Thus, the composition, and hence the mechanical properties, of the copolymer produced from activated sludge can be controlled by adjusting the mole fraction of valeric acid in the feed medium.

Conversion of industrial food wastes by Alcaligenes latus into polyhydroxyalkanoates.

Broader usage of biodegradable plastics in packaging and disposable products as a solution to environmental problems would heavily depend on further reduction of costs and the discovery of novel biodegradable plastics with improved properties. As the first step in our pursuit of eventual usage of industrial food wastewater as nutrients for microorganisms to synthesise environmental-friendly bioplastics, we investigated the usage of soya wastes from a soya milk dairy, and malt wastes from a beer brewery plant as the carbon sources for the production of polyhydroxyalkanoates (PHA) by selected strain of microorganism. Bench experiments showed that Alcaligenes latus DSM 1124 used the nutrients from malt and soya wastes to biosynthesise PHAs. The final dried cell mass and specific polymer production of A. latus DSM 1124 were 32g/L and 70% polymer/cells (g/g), 18.42 g/L and 32.57% polymer/cell (g/g), and 28 g/L and 36% polymer/cells (g/g), from malt waste, soya waste, and from sucrose, respectively. These results suggest that many types of food wastes might be used as the carbon source for the production of PHA.