Herbal Science Research - herbal extract

Red American Ginseng: Ginsenoside Constituents and Antiproliferative Activities of Heat-Processed Panax quinquefolius Roots.

Site Editor — Wed, 06 Jun 2007 00:14:00 -0700

Red American Ginseng: Ginsenoside Constituents and Antiproliferative Activities of Heat-Processed Panax quinquefolius Roots.: Planta Med. 2007 May 31;
Wang CZ, Aung HH, Ni M, Wu JA, Tong R, Wicks S, He TC, Yuan CS

Red Asian ginseng ( PANAX GINSENG C. A. Meyer, Araliaceae) is used in many Oriental countries. In this study, the saponin constituents and anticancer activities of steamed American ginseng ( PANAX QUINQUEFOLIUS L.) roots were evaluated. The contents of 12 ginsenosides in the roots were determined using high performance liquid chromatography (HPLC). After the steaming treatment (100 - 120 degrees C for 1 h and 120 degrees C for 0.5 - 4 h), the quantity of 7 ginsenosides decreased and that of 5 others increased. The content of ginsenoside Rg3, a previously recognized anticancer compound, increased significantly when the root was steamed at 120 degrees C for 0.5 - 3 h. The antiproliferative effects of unsteamed and steamed (120 degrees C for 1 h and 2 h) American ginseng root extracts were assayed by the modified trichrome stain (MTS) method using three cancer cell lines (SW-480, HT-29, NSCLC). Heat-processing increased the antiproliferative effect of American ginseng significantly, and the activity of the extract from roots steamed for 2 h was greater than that of roots steamed for 1 h. Chemical constituents and antiproliferative activities of white and red Asian ginseng have also been evaluated. Five representative ginsenosides, Rb1, Rd, Re, Rg2 and Rg3, were studied. Ginsenoside Rg3 had the most potent effect. The antiproliferative activities of red American ginseng are augmented when ginsenoside Rg3 is increased.

Antioxidant capacity of 55 medicinal herbs traditionally used to treat the urinary system: a comparison...

Site Editor — Wed, 21 Feb 2007 17:59:06 -0800

Antioxidant capacity of 55 medicinal herbs traditionally used to treat the urinary system: a comparison using a sequential three-solvent extraction process.: J Altern Complement Med. 2007 Jan;13(1):103-10 Authors: Wojcikowski K, Stevenson L, Leach D, Wohlmuth H, Gobe G

Background: The prevalence of chronic renal disease exceeds 10% in industrialized societies. Oxidative damage is thought to be one of the main mechanisms involved in nearly all chronic renal pathologies. Objective: We aimed to use the oxygen radical absorbance capacity (ORAC) method and a sequential multisolvent extraction process to compare the in vitro antioxidant capacity of 55 medicinal herbs and prioritize them for in vivo studies investigating the value of herbal therapies in the treatment of renal disorders. Methods: The herbs were chosen on the basis of their traditional use in kidney or urinary system disorders, or because they have attracted the attention of recent investigations into renal pathologies. The three solvents used for extraction were ethyl acetate, methanol, and 50% aqueous methanol. Silybum marianum (milk thistle) seed and Camellia sinensis (tea) leaf, both known to possess high antioxidant capacity, were included for comparison. Results: Twelve of the 55 herbs were comparable to or exceeded ORAC levels of milk thistle seed or tea leaf. The highest radical-scavenging activity was found in Olea europaea (olive leaf), Cimicifuga racemosa (black cohosh), Rheum palmatum (rhubarb), Glycyrrhiza glabra (licorice), and Scutellaria lateriflora (Virginia skullcap). Conclusions: The antioxidant capacity of many of the herbs studied may, at least in part, be responsible for their reputation as being protective of organs of the urinary system. Overall, the combined ORAC values for the methanol and aqueous methanol extracts comprised 84% of the total ORAC value. Sequential extraction with solvents of different polarities may be necessary to fully extract the antioxidant principles from medicinal plants.

The Design and Evaluation of Placebo Material for Crude Herbals: Artemisia afra Herb as a Model.

Site Editor — Wed, 31 Jan 2007 19:11:05 -0800

The Design and Evaluation of Placebo Material for Crude Herbals: Artemisia afra Herb as a Model.: Phytother Res. 2007 Jan 30; Authors: Dube A, Manthata LN, Syce JA

Herbal materials are known to present significant challenges with regard to designing credible placebos. This study intended to demonstrate the possibility of designing placebo material for crude herbals and used Artemisia afra, a popular traditional herbal medicine in South Africa, as a model. To produce the placebo, step-wise solvent extractions were conducted on the plant leaves and the process was monitored spectrophotometrically and using high performance liquid chromatography (HPLC) with diode array detection. The odour and taste between the placebo and A. afra was matched by inclusion of linalool and sodium saccharin, respectively. The muscle relaxant activity of the placebo was evaluated using an isolated guinea-pig tracheal muscle preparation. The UV absorbance of the extracts and the HPLC chromatograms, showed that most of the phytochemical constituents had been removed and the placebo closely resembled the A. afra leaves. The EC(50) of the placebo and the leaves were 4846.00 and 68.49 mg/mL, respectively, which showed that not only did the A. afra leaves possess muscle relaxant activity, but that the placebo did not possess any significant activity compared with the A. afra leaves (p value 0.0001). These results demonstrated that it is possible to design credible, pharmacologically inert placebo material for crude herbals. Copyright (c) 2007 John Wiley & Sons, Ltd.

Hepatoprotective herbal drug, silymarin from experimental pharmacology to clinical medicine.

Site Editor — Sat, 13 Jan 2007 21:35:06 -0800

Hepatoprotective herbal drug, silymarin from experimental pharmacology to clinical medicine.: Indian J Med Res. 2006 Nov; 124(5): 491-504. Authors: Pradhan SC, Girish C

Silymarin, a flavonolignan from 'milk thistle' (Silybum marianum) plant is used almost exclusively for hepatoprotection and amounts to 180 million US dollars business in Germany alone. In this review we discuss about its safety, efficacy and future uses in liver diseases. The use of silymarin may replace the polyherbal formulations and will avoid the major problems of standardization, quality control and contamination with heavy metals or bacterial toxins. Silymarin consists of four flavonolignan isomers namely- silybin, isosilybin, silydianin and silychristin. Among them, silybin being the most active and commonly used. Silymarin is orally absorbed and is excreted mainly through bile as sulphates and conjugates. Silymarin offers good protection in various toxic models of experimental liver diseases in laboratory animals. It acts by antioxidative, anti-lipid peroxidative, antifibrotic, anti-inflammatory, membrane stabilizing, immunomodulatory and liver regenerating mechanisms. Silymarin has clinical applications in alcoholic liver diseases, liver cirrhosis, Amanita mushroom poisoning, viral hepatitis, toxic and drug induced liver diseases and in diabetic patients. Though silymarin does not have antiviral properties against hepatitis virus, it promotes protein synthesis, helps in regenerating liver tissue, controls inflammation, enhances glucuronidation and protects against glutathione depletion. Silymarin may prove to be a useful drug for hepatoprotection in hepatobiliary diseases and in hepatotoxicity due to drugs. The non traditional use of silymarin may make a breakthrough as a new approach to protect other organs in addition to liver. As it is having a good safety profile, better patient tolerability and an effective drug at an affordable price, in near future new derivatives or new combinations of this drug may prove to be useful.

The Induction of CYP1A2, CYP2D6 and CYP3A4 by Six Trade Herbal Products in Cultured Primary Human Hepatocytes.

Site Editor — Sat, 13 Jan 2007 21:34:04 -0800

The Induction of CYP1A2, CYP2D6 and CYP3A4 by Six Trade Herbal Products in Cultured Primary Human Hepatocytes.: Basic Clin Pharmacol Toxicol. 2007 Jan; 100(1): 23-30 Authors: Hellum BH, Hu Z, Nilsen OG

The aim of this study was to evaluate the in vitro inductive potential of six commonly used trade herbal products on CYP1A2, CYP2D6 and CYP3A4 metabolic activities. Herbal components were extracted from the trade products in a way that ensured a composition equal to that present in the original product. Primary human hepatocytes and specific CYP substrates were used. Classic inducers were used as positive controls and herbal extracts were added in in vivo-relevant concentrations. Metabolites were determined by high performance liquid chromatography (HPLC). St. John's wort and common valerian were the strongest inducing herbs. In addition to induction of CYP3A4 by St. John's wort, common valerian and Ginkgo biloba increased the activity of CYP3A4 and 2D6 and CYP1A2 and 2D6, respectively. A general inhibitory potential was observed for horse chestnut, Echinacea purpurea and common sage. St. John's wort inhibited CYP3A4 metabolism at the highest applied concentration. Horse chestnut might be a herb with high inhibition potentials in vivo and should be explored further at lower concentrations. We show for the first time that G. biloba may exert opposite and biphasic effects on CYP1A2 and CYP2D6 metabolism. Induction of CYP1A2 and inhibition of CYP2D6 were found at low concentrations; the opposite was observed at high concentrations. CYP2D6 activity, regarded generally as non-inducible, was increased by exposure to common valerian (linear to dose) and G. biloba (highest concentration). An allosteric activation is suggested. From the data obtained, G. biloba, common valerian and St. John's wort are suggested as candidates for clinically significant CYP interactions in vivo.

Year-and-a-half old, dried Echinacea roots retain cytokine-modulating capabilities in an in vitro human older adult model...

Site Editor — Sat, 06 Jan 2007 19:00:11 -0800

Year-and-a-half old, dried Echinacea roots retain cytokine-modulating capabilities in an in vitro human older adult model of influenza vaccination.: Planta Med. 2006 Oct;72(13):1207-15 Authors: Senchina DS, Wu L, Flinn GN, Konopka del N, McCoy JA, Widrelechner MP, Wurtele ES, Kohut ML

Alcohol tinctures prepared from aged Echinacea roots are typically taken for preventing or treating upper respiratory infections, as they are purported to stimulate immunity in this context. The effects of long-term (> 1 year) dry storage on the capabilities of Echinacea spp. roots from mature individuals to modulate cytokine production are unknown. Using an older human adult model of influenza vaccination, we collected peripheral blood mononuclear cells from subjects 6 months post-vaccination and stimulated them in vitro with the two Type A influenza viruses contained in the trivalent 2004-2005 vaccine with a 50 % alcohol tincture prepared from the roots of one of seven Echinacea species: E. angustifolia, E. pallida, E. paradoxa, E. purpurea, E. sanguinea, E. simulata, and E. tennesseensis. Before being processed into extracts, all roots had been stored under dry conditions for sixteen months. Cells were cultured for 48 hours; following incubation, supernatants were collected and assayed for interleukin-2, interleukin-10, and interferon-gamma production, cytokines important in the immune response to viral infection. Four species ( E. angustifolia, E. purpurea, E. simulata, E. tennesseensis) augmented IL-10 production, diminished IL-2 production, and had no effect on IFN-gamma production. Echinacea pallida suppressed production of all cytokines; E. paradoxa and E. sanguinea behaved similarly, although to a lesser extent. The results from these in vitro bioactivity assays indicate that dried Echinacea roots stored for sixteen months maintain cytokine-modulating capacities. Our data support and extend previous research and indicate that tinctures from different Echinacea species have different patterns of immune modulation; further, they indicate that certain species may be efficacious in the immune response to viral infection.

An approach to the inheritance of the sesquiterpene chemotypes within Petasites hybridus.

Site Editor — Sat, 06 Jan 2007 18:59:20 -0800

An approach to the inheritance of the sesquiterpene chemotypes within Petasites hybridus.: Planta Med. 2006 Oct;72(13):1254-6 Authors: Chizzola R, Langer T, Franz C

Sesquiterpene esters are the active principle in the medicinal plant Petasites hybridus. Two chemotypes, the petasin chemotype and the furanopetasin chemotype, are known, but only the first one is suitable for pharmaceutical purposes. Experimental crossings were performed within and between plants of both chemotypes to study the genetic basis of the occurrence of these sesquiterpenes. The chemotype was determined by TLC in extracts of a small piece of rhizome in the parent plants and the progenies. A model including the combined action of two genes is proposed to explain the inheritance of the chemotypes where the furanopetasin chemotype is under recessive genetic control.

Immunoactive polysaccharide-rich fractions from Panax notoginseng.

Site Editor — Sat, 06 Jan 2007 18:58:21 -0800

Immunoactive polysaccharide-rich fractions from Panax notoginseng.: Planta Med. 2006 Oct;72(13):1193-9 Authors: Zhu Y, Pettolino F, Mau SL, Shen YC, Chen CF, Kuo YC, Bacic A

Panax notoginseng is a commonly used medicinal plant in south-western China. In a previous study, a sequential solubilisation of P. notoginseng high-molecular-weight (HMW) polymers using phenol-acetic acid-water, hot water, weak and strong alkali was performed to determine the structure of the component polysaccharides and proteins. The effects of these extracted HMW fractions on the human complement system, polymorphonuclear neutrophils (PMN) and peripheral blood mononuclear cells (PBMC) are reported here. Fr (1MKOH), which was extracted with 1 M KOH, showed the strongest complement-fixing activity and priming of reactive oxygen species (ROS) production by PMNs, as well as a mitogenic effect. Fr (1MKOH) was further fractionated by anion-exchange chromatography followed by gel-permeation chromatography. 1MD3-G2, the fraction most strongly bound to the DEAE anion-exchange column with a molecular weight of 1140 kDa, showed the highest complement-fixing activity. It is composed of acidic polysaccharides [including glucuronoarabinoxylan (GAX), homogalacturonan (HGA), rhamnogalacturonan I (RG I)], neutral polysaccharides (4-galactan and arabinan), and some protein.

Authentication is fundamental for standardization of Chinese medicines.

Site Editor — Thu, 04 Jan 2007 17:48:02 -0800

Authentication is fundamental for standardization of Chinese medicines.: Planta Med. 2006 Aug;72(10):865-7 Authors: Zhao Z, Hu Y, Liang Z, Yuen JP, Jiang Z, Leung KS

Chinese medicines (CMs) are being used more and more widely throughout the world. Since there are many poisoning incidents caused by misuse or confusion of CMs, their safe use has become a critical issue internationally. In this paper, based on the investigation of the current market of CMs, reasons for various confusions of Chinese Materia Medica (CMM) are analyzed and clarified, such as herbs with multiple sources, regional custom-herbs, confusion in nomenclature, similarity in appearance, and complexity of processed products. Authentication of plant material is critical to the safe and effective use of CMM. In this paper, several authentication methods, such as taxonomy, morphology, microscopy, physical and chemical authentication, DNA molecular biology and their advanced applications in this area, are introduced. Furthermore, it is proposed that an authority on the authentication of CMM be established, as a physical institution and/or as an electronic database.

Overview on the analytical tools for quality control of natural product-based supplements: a case study of ginseng.

Site Editor — Wed, 03 Jan 2007 18:43:30 -0800

Overview on the analytical tools for quality control of natural product-based supplements: a case study of ginseng.Assay Drug Dev Technol. 2005 Dec;3(6):683-99 Authors: Yap KY, Chan SY, Weng Chan Y, Sing Lim C

The quality of pharmaceutical products like ginseng is important for ensuring consumer safety and efficacy. Many ginseng products sold today are in various formulations such as powder, capsules, tablets, soft-gels, liquid extracts, and tea. This renders ginseng less identifiable by smell, taste, or physical appearance. Furthermore, as ginseng is expensive, adulteration with other cheaper products occurs. Hence quality assurance of ginseng is needed. This paper reviews the major techniques for ascertaining the level of ginsenosides, the primary active ingredients for ginseng, and covers high-performance liquid, gas, and thin-layer chromatographies, infrared and nuclear magnetic resonance spectroscopies, enzyme immunoassays, and other molecular methods. Supporting techniques such as ultraviolet, fluorescence, diode array and evaporative light scattering detections, and mass spectrometry will also be touched upon. This review also discusses the principles and applications of biosensors-in particular fiber optic-based sensors-and their feasibility in ginseng analysis based on preliminary studies. Despite their potential, there is currently no or limited commercial exploitation of fiber optic-based sensors to perform ginseng quality analysis. The opportunity for biosensors to be used for the rapid quality surveillance of ginseng is appealing, but several key issues still need to be addressed before they find widespread applications in the traditional Chinese medicine industry.

Recovery of catechin compounds from Korean tea by solvent extraction.

Site Editor — Fri, 06 Oct 2006 16:48:27 -0700

Recovery of catechin compounds from Korean tea by solvent extraction.: Bioresour Technol. 2006 Mar;97(5):790-3 Authors: Row KH, Jin Y

Catechin compounds from Korean green tea as potential sources of anticancer and antioxidant components were target materials in this work. The methodologies of solvent extraction and partition were utilized to recover catechin compounds from green tea. The optimum experimental condition was obtained by optimizing operating factors, such as, the extraction solvent, extraction time and operating temperature. After extracting the green tea with water at 80 degrees C for 40 min, the extract was partitioned with water/chloroform, which was best suited to remove caffeine impurity from the extract. Further, the resulting extract was partitioned water/ethyl acetate to deeply purify the catechin compounds of EGC, EC, EGCG and ECG. The experimental result in this work could be extended to preparative HPLC to obtain EGCG on commercial scale.

Antibacterial activity of crude methanolic extract and its fractions of aerial parts of Anthemis tinctoria.

Site Editor — Wed, 04 Oct 2006 19:04:33 -0700

Antibacterial activity of crude methanolic extract and its fractions of aerial parts of Anthemis tinctoria.: Indian J Biochem Biophys. 2005 Dec;42(6):395-7 Authors: Akgul C, Saglikoglu G

The antibacterial activity of the methanolic extract and its fractions of aerial parts of Aniheinis tinctoria (Asteraceae) was investigated against representative gram-positive Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 29212) and gram-negative strains Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853). The activity was concentrated mainly in the dichloromethane (DCM) and hexane fractions of crude methanolic extract. The 5 mg of DCM extract per disk produced 15-16 mm of inhibition zone against S. aureus and P. aeruginosa, however, no activity was found against E. faecalis and E. coli. The hexane fraction showed activity against S. aureus, P. aeruginosa and E. faecalis. As DCM fraction showed the highest antibacterial activity in the disk diffusion assay, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of only this fraction was determined against S. aureus and P. aeruginosa. These values were found to be in the range of 1.25 to 10 mg/ml.

Multivariate analysis of integrated and full-resolution 1H-NMR spectral data from [...] : St. John's Wort.

Site Editor — Wed, 04 Oct 2006 18:50:35 -0700

Multivariate analysis of integrated and full-resolution 1H-NMR spectral data from complex pharmaceutical preparations: St. John's wort.: Planta Med. 2006 May; 72(6): 556-63 Rasmussen B, Cloarec O, Tang H, Staerk D, Jaroszewski JW

Commercial herbal preparations are typically very complex mixtures and the relationship between content of various constituents and pharmacological action of the formulation is usually unclear. Such formulations are nevertheless standardized using a single marker constituent or a group of closely related constituents, which provides no information about other abundant constituents present in the extract. In this study, principal component analysis of 600 MHz 1H-NMR spectra of extracts of commercial formulations of St. John's wort (Hypericum perforatum), acquired in methanol-d4 and DMSO-d6, was shown to be able to discriminate between various preparations according to their global composition, including differentiation between various batches from the same supplier, while no clustering into classes of tablets and capsules was observed. This suggests that the plant extract variability rather than the manufacturing process accounts for the data clustering. Major variations in the content of flavonoids, recently linked to the antidepressant activity of St. John's wort extracts, were detected. Use of two NMR solvents provided complementary data sets, allowing assessment of various aspects of sample composition from separate PCA models. Both integrated (about 200 variables) and full-resolution NMR data (about 30,000 variables) have been used. The latter approach, applied for the first time in analysis of a herbal preparation, provided via loading plots more precise information about constituents responsible for data clustering, and may be generally preferable for PCA analysis of NMR data of plant extracts and herbal medicines.

Are Extraction Methods in Quantitative Assays of Pharmacopoeia Monographs Exhaustive? A Comparison with Pressurized Liquid...

Site Editor — Wed, 04 Oct 2006 18:33:12 -0700

Are Extraction Methods in Quantitative Assays of Pharmacopoeia Monographs Exhaustive? A Comparison with Pressurized Liquid Extraction.: Planta Med. 2006 Aug 21; Basalo C, Mohn T, Hamburger M

The extraction methods in selected monographs of the European and the Swiss Pharmacopoeia were compared to pressurized liquid extraction (PLE) with respect to the yield of constituents to be dosed in the quantitative assay for the respective herbal drugs. The study included five drugs, Belladonnae folium, Colae semen, Boldo folium, Tanaceti herba and Agni casti fructus. They were selected to cover different classes of compounds to be analyzed and different extraction methods to be used according to the monographs. Extraction protocols for PLE were optimized by varying the solvents and number of extraction cycles. In PLE, yields > 97 % of extractable analytes were typically achieved with two extraction cycles. For alkaloid-containing drugs, the addition of ammonia prior to extraction significantly increased the yield and reduced the number of extraction cycles required for exhaustive extraction. PLE was in all cases superior to the extraction protocol of the pharmacopoeia monographs (taken as 100 %), with differences ranging from 108 % in case of parthenolide in Tanaceti herba to 343 % in case of alkaloids in Boldo folium.

Improved quality control method for Danshen products-Consideration of both hydrophilic and lipophilic active components.

Site Editor — Fri, 09 Jun 2006 07:17:24 -0700

Improved quality control method for Danshen products-Consideration of both hydrophilic and lipophilic active components.: J Pharm Biomed Anal. 2006 Jan 31; Authors: Zhou L, Chow M, Zuo Z

The current study intends to provide an improved quality control analysis for Danshen product-a representative herbal product with known active components that are both hydrophilic and lipophilic in nature. A simple HPLC method with photodiode-array (PDA) ultraviolet detection was developed for the simultaneous determination of three major lipophilic components (cryptotanshinone, tanshinone I and tanshinone IIA) and three major hydrophilic components (danshensu, protocatechuic aldehyde and salvianolic acid B) of Danshen (Salvia miltiorrhiza). These six components were successfully separated using Radial-pak C18 cartridge with the elution gradient consisting of 0.5% acetic acid in water and 0.5% acetic acid in acetonitrile at a flow rate of 1ml/min. The intra-day and inter-day precisions of the analysis were within 2.32 and 2.0%, respectively. The detection limits were 0.02, 0.01, 0.01, 0.05, 0.005 and 0.02mug/ml for cryptotanshinone, tanshinone I, tanshinone IIA, danshensu, protocatechuic aldehyde and salvianolic acid B, respectively. The developed method has been applied to the simultaneous determination of above six major components in Fufang Danshen Tablet and Dripping Pill products by extraction with methanol and water. It has been demonstrated that salvianolic acid B and danshensu are the major components among the eight commercial Fufang Danshen products studied. The current developed method with methanol as extraction solvent provides a simple and efficient method for simultaneous detection of both lipophilic and hydrophilic major components in Danshen products.

Development and stability of semisolid preparations based on a supercritical CO(2) Arnica extract.

Site Editor — Fri, 09 Jun 2006 07:17:02 -0700

Development and stability of semisolid preparations based on a supercritical CO(2) Arnica extract.: J Pharm Biomed Anal. 2006 Jan 31; Authors: Bilia AR, Bergonzi MC, Mazzi G, Vincieri FF

Conventional herbal drug preparations (HDP) based on Arnica montana L. have a low content of the active principles, sesquiterpene lactones, which show poor stability and low physical compatibility in semisolid formulations. Recently, an innovative supercritical carbon dioxide (CO(2)) extract with high sesquiterpene content has been marketed. Development of six semisolid preparations (cetomacrogol, polysorbate 60, polawax, anphyphil, natrosol and sepigel) based on this innovative CO(2) extract is discussed. Stability of these preparations was investigated according to ICH guidelines. The evaluation of in vitro release of active constituents was performed using the cell method reported in the European Pharmacopoeia. Preliminary data on in vivo permeation of three selected formulations is demonstrated using the "skin stripping" test, according to the FDA, in healthy subjects. Analysis of sesquiterpene lactones within the extract and in vitro and in vivo studies was performed by RP-HPLC-DAD-MS method. The cetomacrogol showed the best release profile in the in vitro test, while in the in vivo test the best preparation resulted polysorbate 60 and polawax.

Antibacterial and antioxidant activity of Sutherlandia frutescens (Fabaceae), a reputed anti-HIV/AIDS phytomedicine.

Site Editor — Fri, 09 Jun 2006 04:29:30 -0700

Antibacterial and antioxidant activity of Sutherlandia frutescens (Fabaceae), a reputed anti-HIV/AIDS phytomedicine.: Phytother Res. 2005 Sep;19(9):779-81 Authors: Katerere DR, Eloff JN

Dried ground leaves of Sutherlandia frutescens were extracted by both sequential extraction with four solvents, starting with the least polar and separately with acetone, ethanol and water. The extracts were tested for antibacterial and antioxidant activity. The hexane extract was, generally, the most active extract against S. aureus, E. faecalis and E. coli with MIC values of 0.31, 1.25 and 2.50 mg/mL, respectively. The second method extracted compounds with antioxidant activity as shown by the DPPH free-radical scavenging assay. The use of Sutherlandia frutescens for topical staphylococcal infections, when formulated in an oily base appears to have a rational basis.

Antibacterial and antioxidant activity of Sutherlandia frutescens (Fabaceae), a reputed anti-HIV/AIDS phytomedicine.

Site Editor — Fri, 09 Jun 2006 04:29:16 -0700

Antibacterial and antioxidant activity of Sutherlandia frutescens (Fabaceae), a reputed anti-HIV/AIDS phytomedicine.: Phytother Res. 2005 Sep;19(9):779-81 Authors: Katerere DR, Eloff JN

Hypogylcemic activity of aqueous extract of some indigenous plants.

Site Editor — Fri, 09 Jun 2006 04:26:08 -0700

Hypogylcemic activity of aqueous extract of some indigenous plants.: Pak J Pharm Sci. 2005 Jan;18(1):62-4 Authors: Khan B, Arayne MS, Naz S, Mukhtar N

Pakistan is rich in medicinally important plants and has an ancient herbal treatment methods. Our work is based on the study of some indigenous plants which show inhibitory effect of glucose utilization, and are in use as hypoglycemic agent in traditional system of medicine. Gymnema sylvestre, Momordica charantia and Eugenia jumbolana have been shown to possess hypoglycemic activity of varying degree. The results in three different media revealed that, hypoglycemic activity is more prominent in neutral and basic media as compared to acidic medium.

[Study on the preparation of effervescent tablets of EGb and its quality]

Site Editor — Fri, 09 Jun 2006 04:05:40 -0700

[Study on the preparation of effervescent tablets of EGb and its quality]: Zhong Yao Cai. 2005 Jan;28(1):52-4 Authors: Hu L, Zheng J, Shao S

OBJECTIVE: To prepare effervescent tablets of EGb and establish quality preparation. METHOD: Taking pH, disintegration time and rigidity as index, the formulation and technique of EGb effervescent tablets were optimized by orthogonal experiment, the products were prepared and its stability were tested. RESULT: The optimum procedure condition was adding 12.5% citric acid, 20% sodium bicarbonate encapsulated by PEG6000, the products were tested by stability, the preparation was stable. CONCLUSION: It is valuable to be further studied as a new preparation of EGb.

Pressurized hot water extraction of bioactive or marker compounds in botanicals and medicinal plant materials.

Site Editor — Fri, 09 Jun 2006 03:59:54 -0700

Pressurized hot water extraction of bioactive or marker compounds in botanicals and medicinal plant materials.: J Chromatogr A. 2005 Dec 30; Authors: Ong ES, Cheong JS, Goh D

To reduce the use of organic solvent, pressurized hot water extraction (PHWE) has been shown to be a feasible option for the extraction of bioactive and marker compounds in botanicals and medicinal plants. The parameters that may affect the extraction efficiencies in PHWE include temperature, extraction time and addition of small percentage of organic solvent or surfactants. Currently, applications of PHWE for the extraction of thermally labile compounds in botanicals are still rather limited. PHWE with and without the additional of a small percentage of organic solvent such as ethanol is highly suited for the chemical standardization and quality control of medicinal plants. At the same time, it can be applied at the pilot scale as a manufacturing process for medicinal plants. Surfactant assisted PHWE was found to enhance the extraction of thermally labile and more hydrophobic species in medicinal plants at a lower temperature. The addition of small amount of surfactants in PHWE is highly suited for the determination of bioactive or marker compounds in medicinal plants. With proper optimization, PHWE was observed to have good extraction efficiency and precision when compared to other reference methods of extraction.

Reduction of catechin astringency by the complexation of gallate-type catechins with pectin.

Site Editor — Fri, 09 Jun 2006 03:43:50 -0700

Reduction of catechin astringency by the complexation of gallate-type catechins with pectin.: Biosci Biotechnol Biochem. 2005 Jul;69(7):1306-10 Authors: Hayashi N, Ujihara T, Kohata K

The reductive effect of pectin on tea catechin astringency was investigated by using a taste sensor system and (1)H-NMR spectroscopy. The sensor analysis revealed that the astringency of gallate-type catechins (EGCg and ECg) was reduced by the addition of pectin, whereas that of non-gallate-type catechins (EGC and EC) hardly changed. Changes in the (1)H-NMR chemical shifts of the catechins and pectin in mixed solutions showed that the gallate-type catechins formed complexes with pectin more closely than the non-gallate-type catechins. These results demonstrate that complexation between the gallate-type catechins and pectin is a factor for reducing catechin astringency.

Dry granulation and compression of spray-dried plant extracts.

Site Editor — Fri, 09 Jun 2006 03:43:04 -0700

Dry granulation and compression of spray-dried plant extracts.: AAPS PharmSciTech. 2005;6(3):E359-66 Authors: Soares LA, González Ortega G, Petrovick PR, Schmidt PC

The purpose of this research was to evaluate the influence of dry granulation parameters on granule and tablet properties of spray-dried extract (SDE) from Maytenus ilicifolia, which is widely used in Brazil in the treatment of gastric disorders. The compressional behavior of the SDE and granules of the SDE was characterized by Heckel plots. The tablet properties of powders, granules, and formulations containing a high extract dose were compared. The SDE was blended with 2% magnesium stearate and 1% colloidal silicon dioxide and compacted to produce granules after slugging or roll compaction. The influences of the granulation process and the roll compaction force on the technological properties of the granules were studied. The flowability and density of spray-dried particles were improved after granulation. Tablets produced by direct compression of granules showed lower crushing strength than the ones obtained from nongranulated material. The compressional analysis by Heckel plots revealed that the SDE undergoes plastic deformation with a very low tendency to rearrangement at an early stage of compression. On the other hand, the granules showed an intensive rearrangement as a consequence of fragmentation and rebounding. However, when the compaction pressure was increased, the granules showed plastic deformation. The mean yield pressure values showed that both granulation techniques and the roll compaction force were able to reduce the material's ability to undergo plastic deformation. Finally, the tablet containing a high dose of granules showed a close dependence between crushing strength and the densification degree of the granules (ie, roll compaction force).