[Effects of tree species on polysaccharides content of epiphytic Dendrobium officinale].

To reveals the effects of tree species on polysaccharides content of epiphytic Dendrobium officinale. The polysaccharides content of D. officinale attached to living tress in wild or stumps in bionic-facility was determined by phenol-sulfuric acid method. There were extremely significant differences of polysaccharides content of D. officinale attached to different tree species, but the differences had no relationship with the form and nutrition of barks. The polysaccharides content of D. officinale mainly affected by the light intensity of environment, so reasonable illumination favored the accumulation of polysaccharides. Various polysaccharides content of D. officinal from different attached trees is due to the difference of light regulation, but not the form and nutrition of barks.

Coffee berry borer joins bark beetles in coffee klatch.

Unanswered key questions in bark beetle-plant interactions concern host finding in species attacking angiosperms in tropical zones and whether management strategies based on chemical signaling used for their conifer-attacking temperate relatives may also be applied in the tropics. We hypothesized that there should be a common link in chemical signaling mediating host location by these Scolytids. Using laboratory behavioral assays and chemical analysis we demonstrate that the yellow-orange exocarp stage of coffee berries, which attracts the coffee berry borer, releases relatively high amounts of volatiles including conophthorin, chalcogran, frontalin and sulcatone that are typically associated with Scolytinae chemical ecology. The green stage of the berry produces a much less complex bouquet containing small amounts of conophthorin but no other compounds known as bark beetle semiochemicals. In behavioral assays, the coffee berry borer was attracted to the spiroacetals conophthorin and chalcogran, but avoided the monoterpenes verbenone and α-pinene, demonstrating that, as in their conifer-attacking relatives in temperate zones, the use of host and non-host volatiles is also critical in host finding by tropical species. We speculate that microorganisms formed a common basis for the establishment of crucial chemical signals comprising inter- and intraspecific communication systems in both temperate- and tropical-occurring bark beetles attacking gymnosperms and angiosperms.

Masting in whitebark pine (Pinus albicaulis) depletes stored nutrients.

• In masting trees, synchronized, heavy reproductive events are thought to deplete stored resources and to impose a replenishment period before subsequent masting. However, direct evidence of resource depletion in wild, masting trees is very rare. Here, we examined the timing and magnitude (local vs individual-level) of stored nutrient depletion after a heavy mast event in Pinus albicaulis. • In 2005, the mast year, we compared seasonal changes in leaf and sapwood nitrogen (N) and phosphorus (P) concentrations and leaf photosynthetic rates in cone-bearing branches, branches that never produced cones, and branches with experimentally removed cones. We also compared nutrient concentrations in cone branches and branches that had never had cones between 2005 and 2006, and measured tree ring width and new shoot growth during 2005. • During the mast year, N or P depletion occurred only in tissue fractions of reproductive branches, where photosynthetic rates were reduced. However, by the end of the following year, nutrients were depleted in all branches, indicating individual-level resource depletion. New shoot and radial growth were not affected by masting. • We provide direct evidence that mast events in wild trees deplete stored nutrients. Our results highlight the importance of evaluating reproductive costs over time and at the individual level.

Assessment of mechanisms involved in antinociception caused by myrsinoic acid B.

Myrsinoic acid B (AMB) is a prenylated-benzoic acid derivative isolated from the Rapanea genus. Recent studies suggest that AMB has antihyperalgesic and antinociceptive properties in different animal models. The present study was designed to investigate the mechanisms involved in antinociception elicited by AMB (60 mg/kg) when administered by intraperitonial route (i.p.) in mice. The antinociceptive response of the compound was characterized by a reduction in contractions of the abdominal muscle, together with stretching of the hind limbs in response to i.p. injection of acetic acid (0.6%, 0.45 ml/mouse). The antinociception caused by AMB in the acetic acid test was significantly attenuated by i.p. treatment of mice with nitric oxide precursor, (L-arginine, 600 mg/kg), alpha2 and alpha1-adrenoceptor antagonists (yohimbine, 0.2 mg/kg/prazosin, 0.2 mg/kg), p-chlorophenylalanine (PCPA) an inhibitor of serotonin synthesis (100 mg/kg), 1-(2-methoxyphenyl)-4-(4-phthalimidobutyl)piperazine (NAN 190), a 5-HT1(A) selective receptor antagonist (0.5 mg/kg) and a non-selective cholinergic antagonist (atropine, 10 mg/kg). Its action was also modulated by the adrenal-gland hormones. In contrast, antinociception was not affected by naloxone (non-selective opioid receptor antagonist, 1.0 mg/kg), phaclofen (2.0 mg/kg) and bicuculline (1.0 mg/kg) GABA(B) and GABA(A) receptor antagonists, respectively, ondansetron (0.3 mg/kg) and ketaserin (1.0 mg/kg), (5-HT3 and 5-HT2 receptors, respectively) and haloperidol (0.2 mg/kg), a non-selective dopaminergic receptor. The antinociceptive effects are not related to muscle-relaxant or sedative action. These results indicate that AMB produces antinociception through mechanisms that involve interaction with L-arginine-nitric oxide, the serotonergic and cholinergic systems, as well as interaction with the alpha-adrenoceptors.

The anti-ophidian properties of Anacardium occidentale bark extract.

Snakebites in rural areas of tropical and subtropical regions are commonly treated with medicinal plants. In this report, we have studied the ability of Anacardium occidentale bark extract to neutralize enzymatic as well as pharmacological effects induced by Vipera russelii venom. The extract neutralized the viper venom hydrolytic enzymes such as phospholipase, protease, and hyaluronidase in a dose dependent manner. These enzymes are responsible for both local effects of envenomation such as local tissue damage, inflammation and myonecrosis, and systemic effects including dysfunction of vital organs and alteration in the coagulation components. In addition, extract neutralized the pharmacological effects such as edema, hemorrhage, and myotoxic effects including lethality, induced by venom. Since, it inhibits both hydrolytic enzymes and pharmacological effects; it may be used as an alternative treatment to serum therapy and, in addition, as a rich source of potential inhibitors of hydrolytic enzymes involved in several physiopathological diseases.

[Effects of tree ages and geographic area on quality of bark of Magnolia officinalis and M. officinalis var. biloba].

The effects of tree ages and geographic area on quality of bark of Magnolia officinalis (MO) and M. officinalis var. biloba (MOB) were studied. The volatile oils of samples extracted by a water stream distillation method were analyzed using a GC/MS method. The non-volatile ingredients of samples were determined by an HPLC method. Seven and twenty characteristic peaks were detected in the HPLC and GC fingerprint of MO, respectively, and the similar HPLC and GC fingerprint were showed in MOB. For samples collected in the same geographic area with different ages, the concentrations of active ingredients varied barely, whereas for those samples collected from different geographic area, differences on the concentrations of active ingredients were observed, for example, the concentrations of the amount of magnolol and honokiol in samples collected in Hubei province were higher than those collected in other areas. Big differences on the concentrations of active ingredients were found between MO and MOB, for MO, the ratio of honokiol/ magnolol was more than 0.7, whereas the ratio-was less than 0.7 in the case of MOB, and the concentrations of honokiol in MO were higher than those in MOB.

[Study on effect of picking bud and cutting old branch on the production of root bark of Fengdan in Anhui].

OBJECTIVE: To increase the production of root bark of Fengdan by means of picking bud and cutting old branch cultivated in Nanling, Anhui province. METHODS: An experimental plot where Fengdan has been culitivated for 4 years was selected, which was divided into 3 sections for the experiment of picking bud, cutting old branch and comparison. The buds were picked in spring of the first year. 20 plants were dug randomly from both of picking bud and comparison section monthly during April and September, and the dry weight of their root bark was recorded, respectively. The old branches were cut in autumn. 20 plants were dug randomly from both sections of cutting branch and comparison monthly during April and September of the second year, and their root bark dry weight was recorded. RESULTS: The statistical and comparative results showed that compared to the comparison section, prcking bud section botains little increase of production of root bark, while cutting old branch section had got notable increase of production. CONCLUSION: Picking bud plays an unimportant role in the production of Fengdan bark, while cutting old branch has significant influence on it.

Phloem transdifferentiation from immature xylem cells during bark regeneration after girdling in Eucommia ulmoides Oliv.

Eucommia ulmoides Oliv. (Eucommiaceae), a traditional Chinese medicinal plant, was used to study phloem cell differentiation during bark regeneration after girdling on a large scale. Here it is shown that new sieve elements (SEs) appeared in the regenerated tissues before the formation of wound cambium during bark regeneration after girdling, and they could originate from the transdifferentiation of immature/differentiating axial xylem cells left on the trunk. Assays of water-cultured twigs revealed that girdling blocked sucrose transport until the formation of new SEs, and the regeneration of the functional SEs was not dependent on the substance provided by the axis system outside the girdled areas, while exogenous indole acetic acid (IAA) applied on the wound surface accelerated SE differentiation. The experiments suggest that the immature xylem cells can transdifferentiate into phloem cells under certain conditions, which means xylem and phloem cells might share some identical features at the beginning of their differentiation pathway. This study also showed that the bark regeneration system could provide a novel method for studying xylem and phloem cell differentiation.

Pharmacological actions of Heteromorpha trifoliata ("dombwe") on rat isolated muscle preparations.

OBJECTIVE: To investigate the effects of Heteromorpha trifoliata on rat uterine and skeletal muscle. DESIGN: Laboratory based study using experimental animals. Investigating the effects of the plant extract and agonists on isolated muscle preparations. SETTING: Department of Physiology, University of Zimbabwe. SUBJECTS: 28 Sprague-Dawley rats. MAIN OUTCOME MEASURES: Amplitude of contraction of uterine smooth muscle and skeletal muscle. RESULTS: Experiments were performed on the isolated rat uterus preparation in which strips of myometrium were placed in tissue baths filled with Kreb's solution. The aqueous extract of the root bark of Heteromorpha trifoliata ("dombwe") contracted the rat uterus. The contractions were not antagonised by atropine but were blocked by both cyproheptadine and verapamil. In addition, "dombwe" induced a contracture of the rat diaphragm muscle in the presence of alcuronium. CONCLUSIONS: The contractile effects on the uterus appear to involve stimulation of 5-HT2 receptors leading to an increase in calcium influx into the smooth muscle cell. Promotion of calcium influx could also explain the effects observed on the skeletal muscle preparation since the contracture induced by "dombwe" occurred in the presence of the nicotinic antagonist, alcuronium. In view of the effects of "dombwe" on other smooth muscle preparations (from previous work) it appears that the pharmacological profile of the crude aqueous extract of the root bark of Heteromorpha trifoliata is complex and suggestive of the presence of more than one active ingredient.