Effects of Roasting Conditions on Antibacterial Properties of Vietnamese Turmeric (Curcuma longa) Rhizomes.

Processing with heat treatment has been reported to alter several therapeutic effects of turmeric. In Vietnamese traditional medicine, turmeric has been long used for bacterial infections, and roasting techniques are sometimes applied with this material. However, there have been no studies investigating the effects of these thermal processes on the plant's antibacterial properties. Our study was therefore performed to examine the changes that roasting produced on this material. Slices of dried turmeric were further subjected to light-roasting (80 °C in 20 min) or dark-roasting (160 °C in 20 min) processes. Broth dilution and agar-well diffusion methods were applied to examine and compare the effects of ethanol extracts obtained from non-roasted, light-roasted and dark-roasted samples, on a set of 6 gram-positive and gram-negative bacteria. In both investigations, dark-roasted turmeric was significantly less antibacterial than non-roasted and light-roasted materials, as evident by the higher values of minimum inhibitory concentrations and the smaller diameters of induced inhibitory zones. In addition, dark-roasting was also found to clearly reduce curcumin contents, total polyphenol values and antioxidant activities of the extracts. These results suggest that non-roasting or light-roasting might be more suitable for the processing of turmeric materials that are aimed to be applied for bacterial infections.

Short communication: Antibacterial effects of essential oils from Cinnamomum cassia bark and Eucalyptus globulus leaves-The involvements of major constituents.

Essential oils from Cinnamomum cassia bark and Eucalyptus globulus leaves have been traditionally applied for bacterial infections, through both of aromatherapy and oral application. (E)-cinnamaldehyde and 1,8 cineole have been identified as their major secondary metabolites, and are also generally considered as the main active ingredients responsible for their medicinal applications. However, ethnobotanical doctors still prefer to use whole essentials oils over purified compounds in bacterial infections. We therefore hypothesized that multi-compound extracts might exert better effects than isolated ingredients. In order to verify the hypothesis about advantages of whole materials, we examined antibacterial properties of the 2 plant essential oils in the comparison with their isolated major compounds, such as (E)-cinnamaldehyde and 1,8 cineole. Effects of liquid- and vapor-phase were examined on a set of 6 gram-positive and -negative bacteria, applying broth dilution, agar well diffusion and disc volatilization methods. In all 3 investigations, we observed that whole cinnamon and eucalyptus oils, with the lower concentrations of (E)-cinnamaldehyde (89.1%) and 1,8 cineole (61.2%), were able to induce better effects than the purified active compounds (≥ 99%). These results partly explain the advantages of using whole essential oils over isolated ingredients, and therefore support the application of traditional dosage forms for bacterial infections in ethnomedicine.

Neuroprotective effects of total alkaloids fraction of Huperzia serrata on scopolamine-induced neurodegenerative animals.

Huperzia serrata contains Huperzine A (HupA)-an alkaloid used to treat cognitive dysfunction. In this study, we used the total alkaloids (HsAE) to investigate their potential in managing cognitive impairment in comparison with HupA. The antioxidant activity was measured by DPPH assay. In the cellular study, the cell viability and level of ACh of SH-SY5Y cells were evaluated after pretreated with HsAE and scopolamine. For in vivo assay, mice were pre-treated with HsAE, and HupA and undergone scopolamine injection for cognitive impairment. The behavioral tests including the Y-maze and Morris water maze test and the AChE activity, the SOD, CAT, MDA level in the hippocampus and cortex were evaluated. HsAE showed significant scavenging properties on DPPH radicals. HsAE was not toxic to SH-SY5Y cells, and can rescue these cells upon scopolamine treatment. Intriguingly, HsAE showed the neuroprotection against scopolamine-induced amnesia in mice. Moreover, HsAE decreased AChE activity, MDA level, increased antioxidative enzyme activity in the hippocampus as well as cortex of mice, which was relatively better than that of HupA. These findings suggested that HsAE may significantly protect the neurons of mice with scopolamine-induced memory impairment connected to AChE depletion and oxidative stress.

Insecticidal and Feeding Deterrent Effects of Kaempferia galanga L. and Amomum subulatum on Pieris rapae L. Larva.

<b>Background and Objective:</b> <i>Pieris rapae</i> L., is one of the most widespread and destructive pests of cruciferous plants. At present, synthetic chemical insecticide is still the main approach to control this pest despite several disadvantages to human health and the wildlife environment as well as biological resistance. To search for plants having insecticidal activity, the biological effects of two medicinal plants <i>Kaempferia galanga</i> L. and <i>Amomum subulatum </i>on <i>Pieris rapae</i> L., were investigated. <b>Materials and Methods:</b> The methanol extracts of dry rhizomes and fruits of <i>Kaempferia galanga</i> L. and <i>Amomum subulatum </i>were used to determine the mortality, feeding and oviposition deterrence of larvae and adult of <i>Pieris rapae</i> L. <b>Results:</b> <i>Kaempferia galanga</i> L. and <i>Amomum subulatum</i> exhibited insecticidal activity against <i>Pieris rapae</i> L., with LC₅₀ values of 2.11 and 11.80% (w/v), respectively. In the antifeedant test, <i>Kaempferia galanga</i> L., extract showed no significant difference with the control at the low concentration (0.5 and 1%). Whereas, with a concentration of 0.5%, <i>Amomum subulatum</i> extract demonstrated a high antifeedant effect on <i>Pieris rapae</i> L., larvae. In addition, plants treated with these two extracts reduced eggs laid by <i>Pieris rapae</i> L., in field conditions showing the oviposition deterrent properties. <b>Conclusion:</b> These results indicated that <i>Kaempferia galanga</i> L. and <i>Amomum subulatum </i>extracts have insecticidal substances against <i>Pieris rapae </i>L., which can be used for developing effective pesticides or/and oviposition deterrents for integrated pest management.

Antagonistic Effects of Gingko biloba and Sophora japonica on Cerebral Vasoconstriction in Response to Histamine, 5-Hydroxytryptamine, U46619 and Bradykinin.

The aim of this study was to evaluate, for the first time, the antagonistic effects of Gingko biloba leaf (GB) and Sophora japonica L. flower bud (SJ) extracts on cerebral vasoconstriction in response to KCl, extracellular Ca[Formula: see text], histamine, 5-hydroxytryptamine (5-HT), 9,11-dideoxy-9[Formula: see text],11[Formula: see text]-methanoepoxy prostaglandin (PG) F[Formula: see text](U46619) and bradykinin (BK), in order to explain their traditional application for diseases associated with cerebral vasospasm. Isolated porcine basilar arteries (PBA) and endothelial cells from them were used as the study materials. Neither SJ nor GB had any effect on the contractions induced by KCl and extracellular Ca[Formula: see text]. SJ significantly inhibited the contraction induced by histamine, 5-HT, U46619 and BK, whereas GB inhibited histamine-induced contraction, but had no effects on the contractions induced by 5-HT, U46619 and BK. In the presence of diphenhydramine (a H1 receptor antagonist), ketanserin (a 5-HT2 receptor antagonist) and ONO-3708 (a thromboxane (TX) A2/PG receptor antagonist), the inhibitory effects of these extracts on the contractions induced by histamine, 5-HT and U46619 were abolished. SJ significantly inhibited the contractions induced by BK and PGF[Formula: see text], but in the presence of ONO-3708 (10[Formula: see text] M) had no effect on them. BK enhanced the production of PGF[Formula: see text] from cultured PBA endothelium cells, and SJ significantly attenuated this enhancement. These results suggest that SJ and GB have a H1-antagonistic effect, and that SJ also attenuates cerebral vasoconstriction mediated via 5-HT2 and TXA2/PG receptors. These findings appear to explain why SJ has been used traditionally as a therapeutic medication for cerebral vasospasm after cerebral hemorrhage.

Pharmacological characteristics of Artemisia vulgaris L. in isolated porcine basilar artery.

ETHNOPHARMACOLOGICAL RELEVANCE: In Vietnamese traditional herbalism, there are conflicting opinions about the effect of Artemisia vulgaris L. (AVL, English name: mugwort) on hypertension. Some ethnic doctors recommend the use of AVL for treatment of hypertension, whereas others advise against it. The purpose of this study was to clarify the pharmacological characteristics of AVL in isolated arteries to explain the conflicts surrounding the use of AVL for treatment of hypertension. MATERIALS AND METHODS: We initially performed a functional study using an organ bath system to investigate the effect of AVL extract on isolated porcine basilar artery. We then measured the change in intracellular free Ca(2+) concentration elicited by AVL using cultured smooth muscle cells loaded with the Ca(2+) indicator fluo-4. Finally, using HPLC, we determined the active components in AVL. RESULTS AND DISCUSSION: AVL induced vasoconstriction at resting tension, and endothelial removal enhanced this effect significantly. Pretreatment with PD123319 (an AT2 receptor antagonist), Nω-nitro-L-arginine (a nitric oxide synthase inhibitor), or both, also enhanced this effect. AVL-induced contraction was competitively inhibited by methiothepin (a 5-HT1 and 5-HT2 receptor antagonist) in the presence of ketanserin (a 5-HT2 receptor antagonist). Removal of extracellular calcium with nifedipine (an L-type Ca(2+) channel blocker) or ruthenium red (a ryanodine receptor blocker) significantly reduced AVL-induced contraction, whereas losartan (an AT1 receptor antagonist) and diphenhydramine (a H1 receptor antagonist) had no effect on this contraction. AVL increased the intracellular free Ca(2+) concentration in cultured cells, and this increment was inhibited by methiothepin. HPLC analysis revealed that the retention time of the first peak in the AVL profile was similar to that of the 5-HT standard, and that addition of 5-HT to the AVL sample enhanced this peak. On the other hand, AVL induced endothelium-independent relaxation under precontracted conditions with 60mM KCl. Captopril (an angiotensin converting enzyme inhibitor), atenolol (a ß1 receptor antagonist) and cimetidine (a H2 receptor antagonist) had no effect on this relaxation. In Ca(2+)-free 60mM KCl-containing solution, pretreatment with AVL significantly inhibited CaCl2-induced contraction. CONCLUSION: For the first time, the present study has demonstrated that AVL has two opposite effects, contraction and relaxation, on isolated artery, which may help to explain the conflicting indications for AVL in traditional herbalism. 5-HT is a significant factor affecting artery contraction in the presence of AVL.