In vitro activity of extracts and constituents of Pelagonium against rapidly growing mycobacteria

Extracts of the roots of plants of the Geraniaceae family have been used for many years in South Africa as native herbal remedies and there is circumstantial evidence for efficacy in the treatment of pulmonary tuberculosis. We have examined dried roots of Pelargonium reniforme and P. sidoides for antibacterial activity against rapidly growing mycobacteria. Fractions with activity against Mycobacterium aurum and M. smegmatis were obtained from both plant species by bioassay-guided fractionation of n-hexane extracts and were found to contain mixtures of straight-chain fatty acids. Analysis by gas chromatography–mass spectrometry (GC–MS) of the corresponding fatty acid methyl esters revealed structures with chain lengths ranging from C12 to C26. Unsaturated compounds were analysed as the corresponding dimethyl disulfide adducts to determine double-bond positions. Active mixtures differed in the relative abundance of their components, but all contained 16:0 (palmitic), Δ⁹-18:1 (oleic) and Δ^9,12-18:2 (linoleic acid) as the major components. When tested against M. aurum, M. smegmatis and other rapidly growing mycobacteria (M. fortuitum, M. abscessus and M. phlei), all saturated compounds except 12:0 were devoid of antimycobacterial activity, whereas unsaturated compounds showed antimycobacterial activity related to their degree of unsaturation, their chain length and the bacterial species tested. The most potent compound was linoleic acid, with MIC of 2 mg/l against M. aurum.     

Immunomodulatory principles of Pelargonium sidoides

Extracts and isolated constituents (coumarins and phenols) of Pelargonium sidoides DC, a plant species used in folk medicine by the Southern African native population, were evaluated for their effects on nonspecific immune functions. Although this herbal medicine is also successfully employed in modern phytotherapy in Europe to cure infectious diseases of the respiratory tract, the scientific basis of its remedial effects is still unclear. Thus, functional bioassays including an in vitro model for intracellular infection with Leishmania parasites, an extracellular Leishmania growth assay, a fibroblast-virus protection assay (IFN activity), a fibroblast-lysis assay (TNF activity) and a biochemical assay for inorganic nitric oxides (iNO) were employed. None of the test samples revealed significant activity against extracellular, promastigote Leishmania donovani, the causative agent of human visceral leishmaniasis. In contrast, apart from the coumarin samples, all the Pelargonium extracts (EC(50) <0.1-3.3 microg/mL), gallic acid (EC(50) 4.4 microg/mL) and its methyl ester (EC(50) 12.5 microg/mL) significantly reduced the intracellular survival of L. donovani amastigotes within murine macrophages. These data indicate that the samples acted indirectly on Leishmania parasites, possibly by activating leishmanicidal macrophage functions. Macrophage activation was confirmed by detection of tumour necrosis factor (TNF-alpha) and inorganic nitric oxides (iNO) in supernatants of sample-treated macrophage cultures. Synthesis of iNO is a well-known effector mechanism of macrophages against microorganisms such as Leishmania. Interestingly, blocking iNO-synthase with L-NMMA had no substantial effect on sample-induced intracellular Leishmania kill. From bioassay-guided fractionation, gallic acid and its methyl ester present in large amounts in P. sidoides and in its active extracts, were identified as the prominent immunomodulatory principle for this herbal medicine. The results, when taken together with recent reported antibacterial activity, provide a rational basis for both the traditional and the present utilization of P. sidoides in the claimed conditions.     

Anticoagulant 1,2,3,4,6-pentagalloyl-β-d-glucopyranose isolated from geranium (Pelargonium inquinans Ait)

Geranium (Pelargonium inquinans Ait) leaves were extracted with 80% MeOH, and partitioned into n-hexane, ethyl acetate, BuOH and H2O to isolate the anticoagulant principles. The EtOAc fraction was found to be the most active, and was further purified using silica and octadecylsilane column chromatography employing a bioassay-guided fractionation method. The active compound was isolated and identified as 1,2,3,4,6-pentagalloyl-beta-D-glucopyranose (PGG) (compound I). The isolated anticoagulant significantly prolonged the activated partial thrombin time (APTT) and thrombin time (TT) using normal human plasma. One microgram of 1,2,3,4,6-pentagalloyl-beta-D-glucopyranose showed 0.063 heparin units in the APTT and 2.73 heparin units in the TT for anti-thrombosis. This is the first report of the isolation of PGG from geranium plants.     

Antitubercular Activity of Compounds Isolated from Pelargonium sidoides.

Abstract

The recent increase in the incidence of tuberculosis with the emergence of multidrug-resistant (MDR) cases has lead to the search for new drugs that are effective against MDR strains of Mycobacterium tuberculosis. and can augment the potential of existing drugs against tuberculosis. Pelargonium sidoides. DC (Geraniaceae) is highly valued by traditional healers for its curative properties and is well-known to treat coughs, diarrhea, and tuberculosis. The butanol root extract was found have bioactive inhibitory activity against M. tuberculosis. at a concentration of 2.5 × 10³ µg/mL. Phytochemical analysis of the active fraction from the root of P. sidoides. led to the isolation and identification of six compounds: coumarins (umckalin, scopoletin, 6,8-dihydroxy-5.7-dimethoxy-2H.-benzopyran-2-one, and 6,8-dihydroxy-7-methoxy-2H.-benzopyran-2-one) and flavonoids (catechin and epigallocatechin, which is reported for the first time from P. sidoides.). The isolated compounds were evaluated for antitubercular activity with M. smegmatis. and M. tuberculosis.. Intracellular activity of these compounds was also investigated using THP-1 human macrophages infected with M. tuberculosis.. The isolated compounds did not show activity inhibitory against M. tuberculosis., intracellularly and extracellularly, at the highest concentration tested in the current study. Epigallocatechin and scopoletin showed good inhibitory activity against M. smegmatis., exhibiting a minimum inhibitory concentration (MIC) of 7.8 µg/mL. Catechin and umckalin exhibited MIC values of 31.25 and 62.5 µg/mL, respectively.     

利咽化痰通络法结合超声雾化治疗慢性咽炎的临床观察

目的观察利咽化痰通络法结合超声雾化治疗慢性咽炎的临床疗效。方法180例慢性咽炎患者依照区组随机化法分为安慰剂组、实验组、对照组各60例。安慰剂组用生理盐水20 mL进行超声雾化喷喉,实验组用生理盐水15 mL＋中药天竺雾化剂5 mL行超声雾化喷喉,对照组用庆大霉素8万单位＋地塞米松注射液10 mg＋生理盐水配成20 mL溶液行超声雾化喷喉。每次治疗时间均为10 min,每日1次,持续2周。治疗前、治疗2周后分别观察记录患者临床症状及咽部体征评分。结果治疗后三组的临床症状及咽部体征评分均较治疗前有所下降,差异均有统计学意义（P〈0.05）;但实验组的临床症状及咽部体征评分降低程度及临床疗效均明显优于安慰剂组及对照组,差异均有统计学意义（P〈0.05）。结论利咽化痰通络法结合超声雾化治疗慢性咽炎有良好的临床疗效。     

A historical, scientific and commercial perspective on the medicinal use of Pelargonium sidoides (Geraniaceae)

Ethnopharmacological context

A detailed review of the ethnobotany and commercial history of Pelargonium sidoides is presented, together with a brief summary of pre-clinical and clinical scientific results that support the use of the plant in modern, evidence-based phytomedicines. The aim is to identify the main factors responsible for the success in product development.

Materials and methods

The literature studied includes all modern scientific papers and also old documents and books that are no longer readily accessible.

Results

Available ethnobotanical information shows that several tuberous Pelargonium species (including Pelargonium sidoides) are important traditional medicines with a rich ethnobotanical history. A summary of the interesting history of the commercial development of Stevens’ Cure or Umckaloabo in Europe is presented. Scientific evidence for the efficacy of the product, mainly as a treatment for acute bronchitis, is reviewed. These include numerous in vitro studies as well as 18 clinical studies. The botanical identity of the plant and its complex mixture of coumarins and other chemical constituents are summarised.

Conclusions

The use of Pelargonium stems or tubers for a variety of ailments (including the complications of dysentery) is an important but hitherto under-estimated part of traditional medicine in southern Africa. Key elements in the successful development of Pelargonium sidoides from a profound traditional remedy to a highly successful phytomedicine include the choice of species, a favourable cost–benefit ratio, innovative marketing over many years, good scientific evidence of the botanical and chemical identity of the product and convincing proof of concept.     

香叶天竺葵精油及单体抗氧化能力比较

根据试样对二苯代苦味肼基自由基(DPPH·)的清除作用,评价了香叶天竺葵茎和叶精油及其单体,以及蒸馏后的残渣和废水的抗自由基活性.所试样品中几乎都有一定的抗氧化作用,以中午采集的叶片提取物的DPPH·清除率最高,达99.70%.废水和残渣的清除率分别达97.56%和90.24%.提示天然香料工业所弃的废水和残渣可提取到具有较强的抗自由基活性的物质,为种植香叶天竺葵综合利用提供了可能.     

Methylhexanamine is not detectable in Pelargonium or Geranium species and their essential oils: A multi‐centre investigation

In an earlier study, we developed two sensitive and reliable procedures for gas chromatography‐mass spectrometry (GC‐MS) and liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) analysis of methylhexaneamine (MHA) in P. graveolens plant materials and volatile oils. None of the analyzed plant materials or oils showed any detectable levels of MHA which was further substantiated by high resolution liquid chromatography‐quantum time of flight‐mass spectrometry (LC‐QTOF‐MS) analysis with a limit of detection of 10 ppb. However, other laboratories (two studies) reported the presence of MHA in some samples of P. graveolens and pelargonium oil acquired by the investigators from China. Because of the controversy of whether Pelargonium species or pelargonium oil contains MHA, it was recommended that splits of multiple samples be analyzed by different laboratories. In this investigation, multiple plant materials and oil samples were collected from around the world. These samples were submitted to four different sites for analysis. All sites adopted a similar extraction method. All the analysis sites used LC‐MS/MS or LC‐QTOF‐MS and detection limit was set close to the 10 ng/mL as previously reported. A total of 18 plant samples belonging to 6 different Pelargonium species and 9 oils from different locations around the world were split among 4 different analytical laboratories for analysis (each lab received the same samples). None of the laboratories detected MHA in any of the samples at or around the 10 ppb detection level of the procedure used. Copyright © 2014 John Wiley & Sons, Ltd.     

Studies on the mode of action of essential oils of scented-leaf Pelargonium (Geraniaceae)

A selection of essential oils obtained by steam distillation from scented-leaf Pelargonium species, hybrids and cultivars were assessed for their method of spasmolytic activity in vitro using an isolated smooth muscle preparation. Their mechanism of action was postsynaptic and not atropine-like. The spasmolytic action was correlated with the chemical composition of the essential oils assessed by gas chromatography and mass spectroscopy. The spasmolytic effect of Pelargonium essential oils with a rose-like odour was most likely mediated through cAMP, and not through cGMP; the action of all other essential oils with diverse odours was neither through cAMP, cGMP, nor via calcium channel blockade or potassium channel activation. The mechanism of action of the main components of the rose-like pelargoniums, citronellol and geraniol, reflected that of the whole oils. © 1998 John Wiley & Sons, Ltd.