Piperitone from Mentha longifolia var. chorodictya Rech F. reduces the nitrofurantoin resistance of strains of enterobacteriaceae

The diluted essential oil of Mentha longifolia (L.) var. chlorodictya Rech F. foliage enhanced the bactericidal activity of nitrofurantoin decreasing the minimum inhibitory concentration (MIC) of nitrofurantoin for nitrofurantoin-resistant strains of Enterobacteriaceae. Thin-layer chromatography (TLC) analysis of the essential oil detected a fraction (R(f) = 0.35, UV lambda(max) of 232.5), which was the most effective in enhancement of nitrofurantoin activity. Using gas liquid chromatography and known standards, the active fraction was identified as piperitone. 1 microl of the piperitone fraction decreased the MIC of nitrofurantoin 3-20 fold for the different strains of Enterobacteriaceae tested.     

薄荷冰片和麝香对鼻气道阻力及鼻感觉的影响

祖国医学常将薄荷、冰片作为改善鼻通气药以治疗鼻阻塞，但其作用机理尚不清楚。本实验在５２名受试者中研究了吸入薄荷冰、冰片、麝香对鼻气流阻力及鼻感觉的影响。结果发现这３种具有挥发性的药物都能够不同程度的引起鼻气道通畅的感觉，但对鼻气道阻力却无明显影响。因此作者认为此类药物可称为假性鼻通气药。     

薄荷化学成分的研究

目的:对薄荷非挥发性成分进行研究。方法:利用色谱技术进行分离,波谱技术等方法鉴定结构。结果:从薄荷中分离鉴定9个化合物,分别为大黄素(Ⅰ)、大黄酚(Ⅱ)、大黄紊甲醚(Ⅲ)、苯甲酸(Ⅳ)、反式桂皮酸(Ⅴ)、β-谷甾醇(Ⅵ)、芦荟大黄素(Ⅶ)、熊果酸(Ⅷ)和胡萝卜苷(Ⅸ)。结论:化合物Ⅰ,Ⅱ,Ⅲ,Ⅴ,Ⅶ为首次从薄荷中分离鉴定。     

Antispermatogenic effect of chromatographic fractions isolated from petroleum ether extract of Mentha arvensis leaf in the albino mouse

The antifertility activity of column chromatographically isolated fractions (petroleum ether:benzene 1:1 v/v and chloroform:methanol 1:1 v/v) of a petroleum ether extract of Mentha arvensis leaf were evaluated in the male albino mouse. Administration of the fractions for 20 days at a dose of 1.0 mg/mouse/alternate day reduced the wet weights of genital organs and induced infertility in the male mouse without loss of libido as evaluated by sterile matings with normal proestrus females. Absence of spermatozoa in the cauda epididymes as a consequence of spermatogenic arrest is considered contributory to the antifertility effect. © 1997 John Wiley & Sons, Ltd.     

Phytotherapeutic prevention of dental biofilm formation

The antimicrobial and biofilm formation preventive properties of Mentha piperita and Rosmarinus officinalis essential oils and chlorhexidine were assessed against Streptococcus mutans and Streptococcus pyogenes. 26 and 20 compounds were identified by GC and GC-MS analysis in hydrodistilled oils from M. piperita and R. officinalis, respectively. The minimal bactericidal concentrations (MBC) of the M. piperita and R. officinalis oils and chlorhexidine were (6000, 2000, 8000 ppm) and (1000, 4000, 1000 ppm) for S. mutans and S. pyogenes, respectively. The decimal reduction time (D) of S. mutans exposed to the oils at their MBC levels was 2.8 min while chlorhexidine showed a longer time. The D values of S. pyogenes on exposure to the MBC levels of M. piperita and R. officinalis oils and of chlorhexidine were 2.14, 4.28 and 2.8 min, indicating a higher efficacy of M. piperita oil. Biofilm formation was performed by growing S. mutans culture with and without essential oils in LB medium in polystyrene tubes. In vitro biofilm inhibitory properties were in the order M. piperita > R. officinalis > chlorhexidine. In vivo experiments on the antibiofilm properties revealed that all concentrations of the oils were significantly (p < 0.001) more effective than chlorhexidine. In conclusion, essential oils may be considered as safe agents in the development of novel antibiofilm agents.     

Antibacterial and antifungal activity of essential oils of Mentha suaveolens

The essential oils (EO) of Mentha suaveolens, a wild Labiatae, which grows in several regions in Morocco, were characterized and their antimicrobial activity assessed. The main aromatic constituents of this plant, as characterized by IR, NMR and MS studies, were pulegone, piperitenone oxide (PEO) and piperitone oxide (PO) occurring in different amounts depending on the subspecies. These constituents as well as a series of other aromatic products such as carvone, limonene and menthone, were tested for their antimicrobial activity against 19 bacteria including Gram-positive and Gram-negative and against three fungi, using solid phase and microtitration assays. Pulegone-rich essential oil inhibited efficiently all the micro-organisms tested with MICs ranging between 0.69 and 2.77 ppm. Among the components from Mentha suaveolens EO, pulegone was the most effective against the tested microorganisms, followed by PEO and PO. The structure-activity relationship is discussed on the basis of the activity of the other aromatic derivatives tested such as carvone, limonene, menthone and the profile of the essential oils of Mentha suaveolens was compared with other Mentha species.     

Modulation of serum phosphatases activity in Swiss albino mice against gamma irradiation by Mentha piperita Linn

The modulatory influence of mentha oil (Mentha piperita Linn.) against a lethal dose (8.0 Gy) of gamma irradiation on the activities of serum phosphatases in Swiss albino mice was studied at various post-irradiation intervals between 6 h and 30 days. Mentha oil (40 microL/animal/day) given orally for 3 consecutive days prior to whole-body irradiation (8.0 Gy) showed a modulation of activity of serum phosphatases. The values of acid phosphatase activities were significantly higher in the irradiated groups throughout the experiment compared with the mentha treated unirradiated animals. However, the acid phosphatase activity of mentha treated irradiated animals showed a significant decline over untreated irradiated animals at all autopsy intervals, which attained the normal value on day 5. On the contrary, a marked decrease in serum alkaline phosphatase activity was noted in both irradiated groups but in the mentha treated irradiated group the values of alkaline phosphatase activity were found to be significantly higher than the respective control during the period of study being normal at day 5 post-irradiation and onwards.     

Anti-inflammatory effect of Mentha longifolia in lipopolysaccharide-stimulated macrophages: Reduction of nitric oxide production through inhibition of inducible nitric oxide synthase

Abstract

Mentha longifolia is an aromatic plant used in flavoring and preserving foods and as an anti-inflammatory folk medicine remedy. The present study assessed the effects of M. longifolia extracts, including essential oil and crude methanol extract and its fractions (ethyl acetate, butanol and hexane), on nitric oxide (NO) production and inducible NO synthase (iNOS) mRNA expression in lipopolysaccharide (LPS)-stimulated J774A.1 cells using real-time polymerase chain reaction (PCR). The cytotoxic effects of the extracts on the cells were examined and non-cytotoxic concentrations (<0.2?mg/ml) were used to examine their effects on NO production and iNOS mRNA expression. Only the hexane fraction that contained high levels of phenolic and flavonoid compounds at concentrations from 0.05–0.20?mg/ml significantly reduced NO production in LPS-stimulated cells (p?<?0.001). Real-time PCR analysis indicated the ability of this fraction at the same concentrations to significantly decrease iNOS as well as TNFα mRNA expression in the cells (p?<?0.001). All extracts were able to scavenge NO radicals in a concentration-dependent manner. At concentrations greater than 0.2?mg/ml, total radicals were 100% scavenged. In conclusion, M. longifolia possibly reduces NO secretion in macrophages by scavenging NO and inhibiting iNOS mRNA expression, and also decreases TNFα pro-inflammatory cytokine expression, thus showing its usefulness in the inflammatory disease process.     

薄荷属4种栽培植物的组织形态

薄荷是常用的辛凉解表药,也是广泛用于食品和烟草工业的香料。它的油和脑具很高的经济价值。本文报道国产4种薄荷的形态及解剖研究。对4种薄荷分别进行了性状描写,叶、茎的解剖构造和粉末特征以及花粉粒、小坚果、非腺毛和气孔的电镜扫描观察比较,为薄荷的鉴定和生产提供科学依据。