A botanical, phytochemical and ethnomedicinal review of the genus Mitragyna korth: Implications for products sold as kratom

Publication date: 18 April 2017
Source:Journal of Ethnopharmacology, Volume 202
Author(s): Paula N. Brown, Jensen A. Lund, Susan J. Murch
Ethnopharmacological relevanceThe genus Mitragyna (Rubiacaeae) has been traditionally used in parts of Africa, Asia and Oceania. In recent years, there has been increased interest in species of Mitragyna with the introduction of products to western markets and regulatory uncertainty.Aim of the studyThis paper reviewed the traditional ethnomedicinal uses of leaves for species belonging to the genus Mitragyna with reference to the botany and known chemistry in order to highlight areas of interest for products currently being sold as kratom.Materials and methodsA literature search was conducted using Web of Science, Google Scholar, the Royal Museum for Central Africa, Internet Archive, Hathi Trust, and Biodiversity Heritage Library search engines in the spring of 2015, fall of 2016 and winter of 2017 to document uses of bark, leaf and root material.ResultsLeaves of M. speciosa (kratom) had the most common documented ethnomedicinal uses as an opium substitute or remedy for addiction. Other species of Mitragyna were reportedly used for treating pain, however the mode of preparation was most often cited as topical application. Other uses of Mitragyna included treatment of fever, skin infections, and as a mild anxiolytic.ConclusionsMitragyna species have been used medicinally in various parts of the world and that there is significant traditional evidence of use. Modern products that include formulations as topical application of liniments, balms or tinctures may provide effective alternatives for treatment of certain types of pains. Future research is required to establish safety and toxicology limits, medicinal chemistry parameters and the potential for different physiological responses among varying genetic populations to support regulatory requirements for Mitragyna spp.

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Sutherlandia frutescens modulates adrenal hormone biosynthesis, acts as a selective glucocorticoid receptor agonist (SEGRA) and displays anti-mineralocorticoid properties

Publication date: 18 April 2017
Source:Journal of Ethnopharmacology, Volume 202
Author(s): C.A. Sergeant, D. Africander, P. Swart, A.C. Swart
Ethnopharmacological relevanceSutherlandia frutescens is a traditional African medicinal plant used in the treatment of stress and anxiety, while also exhibiting anti-inflammatory properties.Aim of studyThe study aimed at linking anti-stress and anti-inflammatory properties of S. frutescens to its influence on glucocorticoid biosynthesis and the inflammatory response via steroid receptor interaction.Materials and methodsThe influence of S. frutescens extracts and sutherlandioside B (SUB),10 and 30µM, on key steroidogenic enzymes was assayed in COS-1 cells. Effects were also assayed on basal and stimulated hormone levels in the adrenal H295R cell model. Agonist activity for transactivation and transrepression of the extract and SUB with the glucocorticoid- (GR) and mineralocorticoid receptor (MR) was subsequently investigated.ResultsInhibitory effects of the extract towards progesterone conversion by CYP17A1 and CYP21A2 were significant. SUB inhibited CYP17A1 and 3β-HSD2, while not affecting CYP21A2. In H295R cells, SUB decreased cortisol and androgen precursors significantly. The extract decreased total steroid production (basal and stimulated) with cortisol and its precursor, deoxycortisol, together with mineralocorticoid metabolites significantly decreased under forskolin stimulated conditions. S. frutescens extracts and SUB repressed NF-κB-driven gene expression without activating GRE-driven gene expression and while neither activated MR mediated gene transcription, both antagonized the effects of aldosterone via the MR.ConclusionData provide evidence linking anti-stress, anti-inflammatory and anti-hypertensive properties of S. frutescens to inhibition of steroidogenic enzymes and modulation of adrenal hormone biosynthesis. Findings suggesting S. frutescens and SUB exhibit dissociated glucocorticoid characteristics underline potential therapeutic applications in the treatment of inflammation and hypertension.

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In situ determination of trace elements in Fucus spp. by field-portable-XRF

Publication date: 1 September 2017
Source:Science of The Total Environment, Volumes 593–594
Author(s): Andrew Turner, Hiu Poon, Alex Taylor, Murray T. Brown
Fresh and freeze-dried sample sections of the coastal macroalgae, Fucus serratus and F. vesiculosus, and the brackish water macroalga, F. ceranoides, have been analysed for trace elements by field-portable-X-ray fluorescence (FP-XRF) spectrometry using a Niton XL3t in a low density mode with thickness correction. When analysed fresh in a laboratory accessory stand for a period of 200 seconds, As, Br, Fe and Zn were registered in the apex, mid-frond and lower stipe of all species, with detection limits of a few μg g⁻¹ (As) or a few tens of μg g⁻¹ (Br, Fe, Zn); when analysed dry under the same conditions, concentrations returned were systematically higher and Cu and Pb were detected in a number of F. ceranoides sections. Concentrations arising from both approaches on a dry weight basis were highly correlated, with deviations from unit slope attributed to the absorption of fluorescent X-rays by internal and surficial water when analysed fresh. With algorithms correcting for the effects of water on mass and X-ray absorption, sections of F. vesiculosus and F. ceranoides were analysed in situ with the XRF connected to a mobile stand and laptop. Dry weight concentrations returned for As and Zn were significantly correlated with respective concentrations subsequently determined by ICP-MS following acid digestion and with a slope close to unity; lower concentrations of Fe returned by ICP were attributed to the incomplete acid digestion of silt particles that evaded an initial cleaning step, while Br concentrations could not be verified independently because of loss of volatile forms during digestion. The in situ determination of trace elements in fucoids by FP-XRF provides a rapid and non-destructive means of monitoring environmental quality and identifying hot-spots of contamination, and enables a research strategy to be developed iteratively that is informed by immediate results.

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Topographic, optical and chemical properties of zinc particle coatings deposited by means of atmospheric pressure plasma

Publication date: 15 July 2017
Source:Applied Surface Science, Volume 410
Author(s): L.M. Wallenhorst, L. Loewenthal, G. Avramidis, C. Gerhard, H. Militz, G. Ohms, W. Viöl
In this research, topographic, optical and chemical properties of zinc oxide layers deposited by a cold plasma-spray process were measured. Here, zinc micro particles were fed to the afterglow of a plasma spark discharge whereas the substrates were placed in a quite cold zone of the effluent plasma jet. In this vein, almost closed layers were realised on different samples. As ascertained by laser scanning and atomic force microscopic measurements the particle size of the basic layer is in the nanometre scale. Additionally, larger particles and agglomerates were found on its top. The results indicate a partial plasma-induced diminishment of the initial particles, most probably due to melting or vaporisation. It is further shown that the plasma gives rise to an increased oxidation of such particles as confirmed by X-ray photoelectron spectroscopy. Quantitative analysis of the resulting mixed layer was performed. It is shown that the deposited layers consist of zinc oxide and elemental zinc in approximately equal shares. In addition, the layer's band gap energy was determined by spectroscopic analysis. Here, considerable UV blocking properties of the deposited layers were observed. Possible underlying effects as well as potential applications are presented.

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Highlights

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Detection of norovirus virus-like particles using a surface plasmon resonance-assisted fluoroimmunosensor optimized for quantum dot fluorescent labels

Publication date: 15 July 2017
Source:Biosensors and Bioelectronics, Volume 93
Author(s): Hiroki Ashiba, Yuki Sugiyama, Xiaomin Wang, Haruko Shirato, Kyoko Higo-Moriguchi, Koki Taniguchi, Yoshimichi Ohki, Makoto Fujimaki
A highly sensitive biosensor to detect norovirus in environment is desired to prevent the spread of infection. In this study, we investigated a design of surface plasmon resonance (SPR)-assisted fluoroimmunosensor to increase its sensitivity and performed detection of norovirus virus-like particles (VLPs). A quantum dot fluorescent dye was employed because of its large Stokes shift. The sensor design was optimized for the CdSe-ZnS-based quantum dots. The optimal design was applied to a simple SPR-assisted fluoroimmunosensor that uses a sensor chip equipped with a V-shaped trench. Excitation efficiency of the quantum dots, degree of electric field enhancement by SPR, and intensity of autofluorescence of a substrate of the sensor chip were theoretically and experimentally evaluated to maximize the signal-to-noise ratio. As the result, an excitation wavelength of 390nm was selected to excite SPR on an Al film of the sensor chip. The sandwich assay of norovirus VLPs was performed using the designed sensor. Minimum detectable concentration of 0.01ng/mL, which corresponds to 100 virus-like particles included in the detection region of the V-trench, was demonstrated.



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The distribution of elements in the body of invasive Chinese mitten crabs (Eriocheir sinensis H. Milne-Edwards, 1853) from Lake Dąbie, Poland

Publication date: July 2017
Source:Journal of Food Composition and Analysis, Volume 60
Author(s): Arkadiusz Nędzarek, Przemysław Czerniejewski, Arkadiusz Drost, Filip Harasimiuk, Sylwia Machula, Agnieszka Tórz, Paweł Masalski
The Chinese mitten crab (Eriocheir sinensis) is an invasive species in the Baltic Sea catchment area. Its numbers in fishery are steadily growing and can potentially become a considerable export product. However, the meat of these crustaceans is known to accumulate contaminants, such as trace elements. Therefore, in this study we examined the content of Al, As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, U, Zn in the claws, legs, and carapace of Chinese mitten crabs from Lake Dąbie (south-western catchment area of the Baltic Sea). Concentrations of Mo and U were within the sensitivity limit of the analytical method, and the average concentrations (inmgkg⁻¹dw) of the remaining elements ranged from 0.016 (Cd, claw meat) to 191 (Fe, carapace). The meat had very high concentrations of essential metals (Fe>20, Cu>17, Zn>16, Mn>2, in mgkg⁻¹ dw). The concentrations of Pb and Cd were 5 and 100 times lower than the threshold for foods established by the Commission Regulation (EC) No 1881/2006. The meat of crabs from Lake Dąbie should be safe for consumers and may be a source of elements playing important functions in metabolic processes.



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Differential endozoochory of aquatic invertebrates by two duck species in shallow lakes

Publication date: April 2017
Source:Acta Oecologica, Volume 80
Author(s): Luis Valls, Andreu Castillo-Escrivà, Luis Barrera, Eulalia Gómez, José Antonio Gil-Delgado, Francesc Mesquita-Joanes, Xavier Armengol
Animal vectors are essential for the movement of invertebrate resting eggs between water bodies. However, differences in habitat preferences and feeding behaviour between bird species may result in variations in the dispersal of invertebrates via these birds, even if the different bird species live in the same lake. To test such effects, faecal samples from Anas platyrhynchos (collected in autumn and spring) and Tadorna tadorna (collected in spring) were cultured in water at 20° C and 12 L: 12 D conditions in order to quantify the resting eggs which could be internally transported by these birds. One half of each faecal sample was initially cultured at a conductivity of 0.6 mS cm⁻¹ and the other half at 6 mS cm⁻¹. 1054 invertebrates hatched from a total of 60 faecal samples, including cladocerans, copepods, ostracods, rotifers and ciliates, with a wide variability among faeces. Autumn yielded a low proportion of samples with hatchlings (12.5%) compared to spring (90%). Significant differences were observed between birds, but not between conductivity treatments. Thus, our results imply different hatching dynamics affected by disperser and season, but most species transported as resting eggs by birds seem to have a wide tolerance to hatch under variable salinity conditions. These differences may largery influence the metacommunity dynamics of lake networks, and could be a key factor to consider in wetland conservation planning.



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