Band 68, Heft 11-12

We aimed to determine the differences and similarities between Greek and Turkish propolis with respect to their chemical composition given that the two countries have many similarities in fl oral biodiversity. We observed that: a) Greek propolis is different from the European-type propolis, having a high terpene content; therefore we can definitely characterize it as a Mediterranean type; b) the Turkish propolis collected along the coast line of the Aegean Sea is similiar to the examined Greek propolis; c) the remaining Turkish samples, originating from the European part of Turkey, were found to be similiar to the Europeantype propolis, having a high fl avonoid content. Finally, especially two compounds, β-elemene and totarol, were found in Greek samples in quite high amounts that are thought to have important biological properties.

The rhizome of Phragmites australis has long been used for the treatment of hepatitis in traditional Chinese medicine. In this study, the hepatoprotective and antioxidant activities of an aqueous extract from the rhizome of P. australis (AE-PA) were evaluated. The acute toxicity test in mice showed that AE-PA was nontoxic since a dose of 2000 mg/kg body weight (b.w.) did not cause toxic symptoms or mortality. The prolongation of hexobarbitalinduced sleeping time by carbon tetrachloride (CCl 4 ) administration to mice was significantly reduced after pretreatment with AE-PA at 500 mg/kg b.w., proving the protective effect of the extract on microsomal drug-metabolizing enzyme. The oral administration of AE-PA to rats for 5 days before CCl 4 intoxication caused a significant decrease in the CCl 4 - induced elevation of hepatic enzymes activities in serum, such as aspartate aminotransferase, alanine aminotransferase, and lactic acid dehydrogenase. This suggested that AE-PA had good hepatoprotective activity against CCl 4 -induced liver injury, which was confirmed by pathomorphological examination of the liver. Through evaluation of hydroxyl radical and superoxide anion radical scavenging activities, respectively, it was demonstrated that AE-PA had good antioxidant activity, which possibly contributed to its hepatoprotective activity. More research is needed to study the bio-active compounds in P. australis and to identify the potential hepatoprotective and antioxidant agents.

Several species of the family Bromeliaceae are characterized by the production of proteases in unusual amounts, especially in fruits. Bromelain, an extract rich in cysteine endopeptidases obtained from Ananas comosus L., and a few other proteases have been used as anti-inflammatory agents for some years, but bromelain is still mainly being used as alternative and/or complementary therapy to the treatment with glucocorticoids, nonsteroidal antirheumatics, and immunomodulators. In this study, the anti-inflammatory action of a partially purified extract from Pseudananas macrodontes (Morr.) Harms fruits (PPE Pm ) is presented, whose main components are cysteine endopeptidases. The effect of PPE Pm was assessed in carrageenan-induced and serotonin-induced rat paw edema, as well as in the cotton pellet granuloma model. Doses with equal proteolytic activity of PPE Pm and bromelain produced significantly similar anti-inflammatory responses in the acute inflammatory models assayed, supporting the hypothesis that proteolytic activity could be responsible for the anti-inflammatory action. On the contrary, comparable anti-inflammatory effects of PPE Pm and bromelain in the chronic inflammatory assay required a much lower proteolytic activity content of PPE Pm , which could be due to a differential affinity for the protein target involved in this process.

A new series of 5-(p-substituted benzamido/phenylacetamido)-2-(p-tert-butylphenyl)benzoxazole derivatives were synthesized and evaluated for their antibacterial, antifungal, and antimycobacterial activities against antibiotic-resistant and -sensitive Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, and Mycobacterium tuberculosis as well as against Candida albicans and Candida krusei. The compounds possessed broad-spectrum activity against all of the tested Gram-positive and Gram-negative bacteria and yeasts, their minimum inhibitory concentrations (MICs) ranging between 16 - 128 μg/ml. One compound exhibited significant antibacterial activity (16 μg/ml) against an antibioticresistant Enterococcus faecalis isolate, having twice the potency of the compared standard drugs vancomycin and gentamycin sulfate. The compounds also showed moderate antitubercular activity with MIC values between 8 - 128 μg/ml against Mycobacterium tuberculosis and its clinical isolate.

Applying a bioactivity-guided isolation strategy for the ethanolic extract of crown gall tumours induced on an Eucalyptus tereticornis tree, two new compounds in addition to a known one were isolated. The new compounds were identified as an amino acid derivative named 1-ethyl-6-(1´-methyl-1´-phenylethyl) piperidin-2-one (1) and a lanostane tetracyclic triterpene named 3β-hydroxy-24-methyllanosta-8,17(20),24(28)-trien-22-oic acid (2), together with stigmasterol-3-O-glucoside (3). The three compounds exhibited significant cytotoxic activity against two human cell lines, breast (MCF7) and colon (HCT116), with IC 50 values of 1.01, 1.54, and 2.15 μg/ml, respectively, against MCF7 and 3.49, 3.83, and 3.39 μg/ ml, respectively, against HCT116. Furthermore, in rats elevated levels of blood cholesterol, triglycerides, and low-density lipoprotein (LDLc) were significantly reduced, while the level of high-density lipoprotein (HDLc) was significantly increased by administration of the ethanolic extract as well as of 3. These results support a correlation between the reduction of blood cholesterol levels and improvement of colorectal cancer.

Photobacterium damselae subsp. piscicida (Phdp) is the causative agent of fish photobacteriosis (pasteurellosis) in cultured cobia (Rachycentron canadum) in Taiwan. A component was purified from the extracellular products (ECP) of the bacterium strain 9205 by fast protein liquid chromatography (FPLC) and identified as a phospholipase. An N-terminal sequence of 10 amino acid residues, QDQPNLDPGK, was determined by mass spectroscopy (MS) and found to be identical with that of another Phdp phospholipase (GenBank accession no. BAB85814) at positions 21 to 30. The corresponding gene sequence of the phospholipase (GenBank accession no. AB071137) was employed to design primers for amplification of the sequence by the polymerase chain reaction (PCR). The PCR products were transformed into Escherichia coli, and a recombinant protein product was obtained which was purified as a His-tag fusion protein by Ni-metal affinity chromatography. A single 43-kDa band was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Phosphatidylcholine was degraded by this protein to lysophosphatidylcholine and a fatty acid. These products were characterized by thin-layer (TLC) and gas chromatography (GC), respectively, allowing the identification of the protein as a phospholipase A 2 . The recombinant protein had maximum enzymatic activity between pH 4 and 7, and at 40 °C. The activity was inhibited by Zn 2+ and Cu 2+ , activated by Ca 2+ and Mg 2+ , and completely inactivated by dexamethasone and p-bromophenacyl bromide. A rabbit antiserum against the recombinant protein neutralized the phospholipase A 2 activity in the ECP of Phdp strain 9205 and the recombinant protein itself. The recombinant protein was toxic to cobia of about 5 g weight with an LD 50 value between 2 and 4 μg protein/g fish. The results revealed phospholipase A 2 as a fish toxin in the ECP of Phdp strain 9205.

The content of six ginsenosides (Rb1, Rb2, Rc, Rd, Rg1, and Re) was studied in the roots of field-grown plants, as well as in root-forming callus cultures and adventitious root cultures of Panax quinquefolium using high-performance liquid chromatography (HPLC). The highest level of saponins was isolated from root hairs (128 mg/g dry weight). The examined in vitro culture synthesized all identified saponins, although in smaller amounts than those obtained from field cultivation. Metabolites Rb1 and Re dominated in the ginseng biomass from both field crops and in vitro culture.

To produce novel types of sophorose lipids containing an odd number of carbon atoms in the lipophilic moiety, Candida bombicola ATCC 22214 was grown in 500-ml fl ask cultures with glucose as main carbon source, and additionally, 2-tridecanone as co-substrate. After solvent extraction, the crude product mixture was separated into pure fractions, and each fraction was analysed via NMR and mass spectroscopy. This effective strategy generated five new glycolipids, 2-tridecyl sophorosides, which differed in the number of glucose units, and acetyl and hydroxy groups, respectively. Based on these compounds, a proposal for the possible biosynthetic pathway was deduced. Two compounds of the mixture, mono- and diacetylated 2-tridecyl sophorosides, respectively, were able to lower the surface tension of water from 72 mN m -1 to 32 mN m -1 and the interfacial tension between water and nhexadecane from 43 mN m -1 down to 4 and 3 mN m -1 . Thus, both compounds possess a very good surfactant behaviour. Moreover, it was observed that the new products inhibit the growth of particular Gram-positive bacteria, and they indicate potential for antitumourpromoting activity.

Olimarabidopsis pumila is a close relative of the model plant Arabidopsis thaliana but, unlike A. thaliana, it is a salt-tolerant ephemeral plant that is widely distributed in semi-arid and semi-salinized regions of the Xinjiang region of China, thus providing an ideal candidate plant system for salt tolerance gene mining. A good-quality cDNA library was constructed using cap antibody to enrich full-length cDNA with the gateway technology allowing library construction without traditional methods of cloning by use of restriction enzymes. A preliminary analysis of expressed sequence tags (ESTs) was carried out. The titers of the primary and the normalized cDNA library were 1.6 · 10 6 cfu/mL and 6.7 · 10 6 cfu/mL, respectively. A total of 1093 clones were randomly selected from the normalized library for EST sequencing. By sequence analysis, 894 high-quality ESTs were generated and assembled into 736 unique sequences consisting of 72 contigs and 664 singletons. The resulting unigenes were categorized according to the gene ontology (GO) hierarchy. The potential roles of gene products associated with stress-related ESTs are discussed. The 736 unigenes were similar to A. thaliana, A. lyrata, or Thellungiella salsuginea. This research provides an overview of the mRNA expression profile and first-hand information of gene sequence expressed in young leaves of O. pumila.

Cytochrome P450 proteins, widely distributed multifunctional enzymes, are mainly involved in biosynthetic and degradative pathways of endogenous compounds and the detoxification of xenobiotics in insects. Moreover, these enzymes exhibit peroxidase-like activity, therefore they may be involved in protecting organisms against the toxicity of reactive oxygen species (ROS). In the present study, we cloned a CYP4G11 gene - AccCYP4G11 - from the Chinese honey-bee (Apis cerana cerana). The open reading frame of the cDNA was 1656 bp long and encoded a 551 amino acids polypeptide, which shared high sequence identity with homologous cytochrome P450 proteins. In the genomic DNA sequence, a 5'-flanking region consisting of 1168 bp was obtained, and some putative transcription factor binding sites were predicted. Quantitative polymerase chain reaction (Q-PCR) revealed that the level of AccCYP4G11 was higher in the epidermis than in other tissues, and Acc- CYP4G11 was expressed in all stages with the highest level in two-week-old adult worker honey-bees. More over, the expression patterns under oxidative stress indicated that Acc- CYP4G11 transcription was significantly influenced by external factors, such as temperature challenges, ultraviolet (UV) light, and insecticide treatment. AccCYP4G11 was regulated differentially in response to oxidative stress and may be involved in protecting honey-bees from oxidative injury.

Wheel bugs (Heteroptera: Reduviidae: Harpactorinae: Arilus) are general predators, the females of which have reddish-orange subrectal glands (SGs) that are eversible like the osmeteria in some caterpillars. The rancid odor of Arilus and other reduviids actually comes from Brindley's glands, which in the North (A. cristatus) and South (A. carinatus) American wheel bugs studied emit similar blends of 2-methylpropanoic, butanoic, 3-methylbutanoic, and 2-methylbutanoic acids. The Arilus SG secretions studied here are absolutely species specific. The volatile SG components of A. carinatus include (E)-2-octenal, (E)-2-nonenal, (E)-2-decenal, (E,E)-2,4-nonadienal, (E)-2-undecenal, hexanoic acid, 4-oxo-nonanal, (E,E)-2,4-decadienal, (E,Z)-2,4- or (Z,E)-2,4-decadienal, and 4-oxo-(E)-2-nonenal; whereas in A. cristatus the SG secretion contains β-pinene, limonene, terpinolene, terpinen-4-ol, thymol methyl ether, α-terpineol, bornyl acetate, methyl eugenol, β-caryophyllene, caryophyllene oxide, and farnesol. Arilus spp. SG secretions may be sex pheromones, but verification of this hypothesis requires further testing.