Antioxidant and antimicrobial activities of essential oil and extracts of Saurauia lantsangensis hu root.

Antioxidant and antimicrobial activities of the essential oil and n-hexane (HEE), chloroform (CHE), ethyl acetate (EAE), and methanol (MEE) extracts, respectively, from the root of Saurauia lantsangensis Hu were investigated. The GC-MS analysis revealed 39 compounds representing 96.41% of the oil containing T-muurolol (13.85%), acetophenone (7.46%), alpha-cadinol (6.26%), methyl palmitate (5.36%), n-hexadecanoic acid (4.31%), torreyol (3.69%), and isospathulenol (3.48%) as major components. Antioxidant activities determined by three various testing systems, i.e., DPPH radical scavenging, superoxide anion radical scavenging, and reducing power assay, increased in the order: HEE < CHE < oil < MEE < EAE. CHE, EAE, MEE and oil exhibited a promising antimicrobial effect determined as the diameter of zones of inhibition (13.3-16.2, 16.5-20.4, 13.5-16.6, and 16.5-22.7 mm), respectively, along with their respective MIC values (500-1000, 125-500, 250-500, and 250-500 microg/ml) against Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli), Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus), and a yeast (Hansenula anomala).

28-day repeated dose oral toxicity of human copper-zinc superoxide dismutase from recombinant Pichia pastori in rats.

Human copper/zinc superoxide dismutase from recombinant Pichia pastori (RH-Cu/Zn-SOD) was orally administered, via gavage, to Sprague-Dawley rats at 500, 1,000, and 2,000 mg/kg body weight/day for 28 days. During the 28-day period, animals were examined for evidence of toxicity; there were no deaths, and in-life physical signs were normal. On day 29, the animals were exsanguinated, examined for gross pathology, and tissues were preserved for histopathology. Although statistical differences were noted in some hematology and clinical chemistry, they were of questionable biological significance. The results of the 28-day oral administration demonstrated a lack of toxicity of RH-Cu/Zn-SOD in rats. There were no treatment-related, toxicologically relevant changes in clinical signs, growth, food consumption, hematology, clinical chemistry, organ weights, or pathology. The no observed adverse effect level was greater than 2,000 mg/kg/day for RH-Cu/Zn-SOD in rats.

Chemical composition and larvicidal effects of essential oil of Blumea martiniana against Anopheles anthropophagus.

OBJECTIVE: To determine chemical composition of the hydrodistilled essential oil of Blumea martiniana, and to evaluate its larvicidal activity against Anopheles anthropophagus, the natural vector of malaria. METHODS: Chemical composition of essential oils extracted by steam distillation was investigated by gas chromatography and mass spectroscopy (GC-MS). Larvicidal activity of essential oil and its four main compounds was carried out by WHO method. Twenty larvae of early fourth-instar stage were used in the larvicidal assay and five replicates were maintained for each concentration. The 24 h LC(50) and LC(90) values were determined following probit analysis. RESULTS: Totally 68 compounds corresponding to 98.55% of the total oil were identified and the major constituents of essential oil were: linalool(10.36%), germacrene D(9.09%), borneol(6.24%), γ-terpinene(5.38%). The oil and linalool, germacrene D, borneol, γ-terpinene exerted significant larvicidal activity with LC(50) values of 46.86, 35.87, 44.61, 35.89, and 29.21 mg/L, respectively. It also showed a dose dependent effect on mortality. CONCLUSIONS: The essential oil of Blumea martiniana and its four major compounds may have potential for use in control of Anopheles anthropophagus larvae and could be useful in search of newer, safer and more effective natural compounds as larvicides.

Chemical composition and antimicrobial activities of essential oil of Blumea megacephala.

Blumea megacephala essential oil, obtained through steam distillation of samples collected from the Shiwang Mountains in Guangxi Province, China, was analyzed using GC-FID and GC-MS. Among the 65 compounds identified in the oil, the main compounds were borneol (13.6 %), ß-caryophyllene (9.56 %), germacrene D (9.09 %), sabinene (6.37 %), and α-humulene (4.78 %). Antimicrobial activity revealed that the essential oil (1000 µg/disc) has promising antimicrobial effects against several pathogens, giving satisfactory inhibition zone diameter values (21.5, 21.6, 23.4, 23.8, 21.9) and MIC values (125, 125, 62.5, 125, 125 µg/ml) against Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli), Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus), and yeast (Hansenula anomala). Antioxidant and antimicrobial activities were correlated with chemical composition.

[Studies on the antioxidative activity of polysaccharides from radix Saposhnikoviae].

OBJECTIVE: To research the antioxidant activity of polysaccharides from Saposhnikovia divaricata (Turez.) Schischk. METHOD: Polysaccharides from Saposhnikovia divaricata (Turez.) Schischk were obtained through hot water extracting and ethanol precipitating method. Using CTAB as precipitant, Saposhnikovia polysaccharide was separated into acid Saposhnikovia polysaccharide (A-SPS) and neutral Saposhnikovia polysaccharide (N-SPS). The total reducing power, scavenging effect to superoixide anion (O2-*), hydroxyl radical (*OH), 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH*) and inhibiting effect to lipid-peroxidation induced by Fe2+ of different Saposhnikovia polysaccharides were measured in vitro chemical simulated systems for evaluating their antioxidant activity. RESULTS: Saposhnikovia polysaccharides had some functions of scavenging free radicals and inhibiting lipid peroxidation, and scavenging effects on DPPH* and OH* were especially significant. A-SPS had better effect among different Saposhnikovia polysaccharides, and the scavenging rate of DPPH* and OH* could approach to 70% when the experimental concentration was 8 mg/ml . CONCLUSION: A-SPS, potential main active ingredient of Saposhnikovia polysaccharide, has strong antioxidant activity and can be applied as a potential natural antioxidant in food and medicine industry.