椒样薄荷、薄荷和苏格兰留兰香精油与抗生素的协同抑菌功能

以开花期的椒样薄荷（Mentha×piperita）、薄荷（M.haplocalyx）和苏格兰留兰香（M.×gentilis）叶片部位提取的精油为研究对象,通过GC-MS分析,并采用纸片扩散法研究了3种精油单独使用及与抗生素联合使用时对金黄色葡萄球菌、蜡状芽孢杆菌、大肠杆菌、绿脓杆菌和肺炎克雷伯氏菌的抑制情况。结果表明,（1）椒样薄荷与薄荷精油中含量最高的成分为薄荷醇、薄荷酮和异薄荷酮,苏格兰留兰香精油的主要成分为香芹酮和柠檬烯。薄荷和苏格兰留兰香精油符合欧洲药典与ISO标准,椒样薄荷需要继续改良以提高其精油品质与抑菌功能。（2）精油单独使用时,Pseudomonas aeruginosa ATCC15442对椒样薄荷精油和薄荷精油敏感;P.aeruginosa ATCC27853对薄荷精油和苏格兰留兰香精油敏感。精油与抗生素联合使用时抑菌范围和强度均有所改变：绿脓杆菌的2个菌株对精油与抗生素的组合最为敏感,其中,椒样薄荷精油与头孢他啶的组合对P.aeruginosa ATCC15442显示出最强的增效作用,薄荷精油与头孢他啶混合之后对P.aeruginosa ATCC27853出现拮抗作用。Staphylococcus aureus ATCC25923对所有精油以及精油与抗生素混合物均有抗性。（3）椒样薄荷、薄荷和苏格兰留兰香精油的不同成分及其含量差异不仅对精油品质有影响,而且影响精油对测试菌种的抑制作用,可考虑将其作为薄荷属植物品质育种的参考指标。     

椒样薄荷、薄荷和苏格兰留兰香精油与抗生素的协同抑菌功能

以开花期的椒样薄荷(Mentha × piperita)、薄荷(M. haplocalyx)和苏格兰留兰香(M. × gentilis)叶片部位提取的精油为研究对象, 通过GC-MS分析, 并采用纸片扩散法研究了3种精油单独使用及与抗生素联合使用时对金黄色葡萄球菌、蜡状芽孢杆菌、大肠杆菌、绿脓杆菌和肺炎克雷伯氏菌的抑制情况。结果表明, (1) 椒样薄荷与薄荷精油中含量最高的成分为薄荷醇、薄荷酮和异薄荷酮, 苏格兰留兰香精油的主要成分为香芹酮和柠檬烯。薄荷和苏格兰留兰香精油符合欧洲药典与ISO标准, 椒样薄荷需要继续改良以提高其精油品质与抑菌功能。(2) 精油单独使用时, Pseudomonas aeruginosa ATCC 15442对椒样薄荷精油和薄荷精油敏感; P. aeruginosa ATCC 27853对薄荷精油和苏格兰留兰香精油敏感。精油与抗生素联合使用时抑菌范围和强度均有所改变: 绿脓杆菌的2个菌株对精油与抗生素的组合最为敏感, 其中, 椒样薄荷精油与头孢他啶的组合对P. aeruginosa ATCC 15442显示出最强的增效作用, 薄荷精油与头孢他啶混合之后对P. aeruginosa ATCC 27853出现拮抗作用。Staphylococcus aureus ATCC 25923对所有精油以及精油与抗生素混合物均有抗性。(3) 椒样薄荷、薄荷和苏格兰留兰香精油的不同成分及其含量差异不仅对精油品质有影响, 而且影响精油对测试菌种的抑制作用, 可考虑将其作为薄荷属植物品质育种的参考指标。     

不同产量水平椒样薄荷栽培措施调查分析

对伊犁地区不同产量条田椒样薄荷进行调查,分析促进椒样薄荷高产的必要措施。研究发现合适的种植密度是椒样薄荷高产的先决条件,多年生椒样薄荷每667 m~2出苗密度在4-5.5万株时,椒样薄荷才具有高产的潜能;高产薄荷具有返青早、生长势强的特点,但仅通过生物状无法判断椒样薄荷产量。椒样薄荷产量高低与收割时间及管理措施相关,但与土壤的肥力水平无明显相关性。     

滇产薄荷的化学研究

研究了滇产３８个薄荷样品,测定了样品的得油率及化学成分。滇产薄荷的得油率在０．１８％￣０．５２％之间。从挥发油中鉴定出了１００多种化学成分,主要含醇、酮、酯、萜烯类化合物。栽培的家薄荷挥发油富含香芹酮、柠檬烯,其化学分类属于香芹酮系列。野生薄荷挥发油富含薄荷醇和薄荷酮,属于薄荷酮系列;部分野薄荷样品,富含香芹酮、环氧辣薄荷烯酮或芳樟醇,属于混合系列。     

国外薄荷属植物精油积累的生理和生态学研究

薄荷油和留兰香油都是从薄荷属植物中得到的重要天然香料。这些精油的组成非常复杂,例如椒样薄荷(Mentha piperita)油已发现120多种成分,苏格兰留兰香(M.cardiaca)油含有194种化合物。但它们的主体成分都是对(艹孟)烷衍生物——单萜化合物。在生产实践中,植物的含油率,以及精油的化学组成、物理化学常数和香气香味,在不同的栽培地区、气候条件和收获期存在明显的差异。这就引起了植物学家、植物化学家和香     

基于RAPD标记的薄荷属(Mentha L.)植物亲缘关系分析

应用RAPD标记方法分析了薄荷属(Mentha L. )7个种38个种源间的遗传多样性,并采用UPGMA聚类分析方法探讨了38个种源间的亲缘关系.结果表明,用20条随机引物从38个种源的总DNA中共扩增出111条带,其中多态性条带91条,多态性条带百分率达81.98%,表明薄荷属植物种间和种内存在丰富的遗传多样性.聚类分析结果表明,在遗传相似系数0.43 处,供试的38个种源被分为2大类,其中第1大类包含日本薄荷(M. arvensis L. )、灰薄荷(M. vagans Boriss. )、留兰香(M. spicata L. )、皱叶留兰香(M. crispata Schrad. ex Willd. )、椒样薄荷(M.×piperita L. )和薄荷(M. haplocalyx Briq. )的37个种源,第2大类仅包含唇萼薄荷(M. pulegium L. )1个种源.在遗传相似系数0.74处,38个种源被分为6组:A组仅包含日本薄荷1个种源;B组包含灰薄荷的4个种源;C组包含留兰香的2个种源和皱叶留兰香的6个种源;D组包含椒样薄荷的5个种源和留兰香的2个种源;E组包含薄荷的17个种源;F组仅包含唇萼薄荷1个种源.在遗传相似系数0.83处,B组、C组、D组和E组可各自进一步划分为不同的亚组.研究结果显示,基于RAPD标记分析的聚类分析结果与传统形态学分类结果基本相吻合;同一种类来源相同或相近的种源聚在一起,说明薄荷属植物种内的遗传关系与地理分布和环境差异有一定的相关性.     

椒样薄荷试管苗生根的影响因素分析

椒样薄荷(M entha piperitaL.)为多年生宿根型长日照植物,原产美国密执安、威斯康星及印第安纳等地[1],中国黑龙江、陕西、新疆、河北、江苏、浙江及安徽等地有少量引种栽培[2~4]。从其茎叶中提取的芳香挥发油具有辛辣凉爽的香气,广泛用于医药、牙膏、牙粉、糖、饮料和酒等产业     

一种根癌农杆菌介导的耐盐椒样薄荷含芽茎段转化系统

椒样薄荷的转基因技术是提高精油产量和品质的重要手段,为解决耐盐椒样薄荷叶片不定芽诱导过程中易褐化,难分化,不适合作为转基因外植体的问题,利用含芽的椒样薄荷茎段作为外植体建立了一种根癌农杆菌介导的外源基因转化体系。利用正交试验对转化所用的根癌农杆菌菌液浓度、转化时间和共培养时间进行优化,结果显示:3个因素对转化效果的影响作用表现为转化时间(B)菌液浓度(A)共培养时间(C),筛选出的最优转化条件为菌液浓度为OD_(600)=0.8,转化时间为15 min,共培养时间为3 d。对不同转化液组分进行优化筛选,结果获得最适的转化液组分为:1/5MS+0.5 g/L MES(2-(N-吗啡啉)乙磺酸)+1%葡萄糖+2%蔗糖,PH5.4。利用不同植物表达载体进行转化,并通过基因组PCR和GUS染色进行转化植株的阳性检测,结果表明该转化体系适用于多种植物表达载体的转化,容易获得再生植株,为耐盐椒样薄荷的基因转化提供新的方法与体系。     

满天香精油化学成分的研究

采用Finngan-4510型毛细管气相色谱/质谱/电子计算机联用(GC/MS/DS)技术,辅以~1H NMR,~18C NMR和化学的手段,对广西龙州产满天香精油进存定性定量分析,分离出37个组分,鉴定了其中26个,占精油总量的97.40％。其主要成分为薄荷酮(51.09％)、异满天酮(7.95％)、(+)-新薄荷醇(19.42％)、枞油烯(5.71％)、薄荷醇,β-水芹烯等。薄荷香是一种富含薄荷酮、薄荷醇的新资源植物。     

国产野生薄荷挥发油化学组分变异及其化学型

采用气－质联用的方法,对国产野生薄荷（ＭｅｎｔｈａｈａｐｌｏｃａｌｙｘＢｒｉｑ．）居群的挥发油成分进行了分析,２２个样品可归纳为６个化学型：（１）薄荷酮－胡薄荷酮型（ｍｅｎｔｈｏｎｅ－ｐｕｌｅｇｏｎｅｔｙｐｅ）;（２）胡椒酮型（ｐｉｐｅｒｉｔｏｎｅｔｙｐｅ）;（３）氧化胡椒酮－氧化胡椒烯酮型（ｐｉｐｅｒｉｔｏｎｅｏｘｉｄｅ－ｐｉｐｅｒｉｔｅｎｏｎｅｏｘｉｄｅｔｙｐｅ）;（４）芳樟醇－氧化胡椒酮型（ｌｉｎａｌｏｏｌ－ｐｉｐｅｒｉｔｏｎｅｏｘｉｄｅｔｙｐｅ）;（５）香芹酮型（ｃａｒｖｏｎｅｔｙｐｅ）;（６）薄荷醇－乙酸薄荷酯型（ｍｅｎｔｈｏｌ－ｍｅｎｔｈｙｌａｃｅｔａｔｅｔｙｐｅ）。结合地理分布和薄荷属单萜类成分生物合成途径,对上述主要类型进行了讨论。     

Composition,Chemical Variability and Biological Activity of Cymbopogon schoenanthus Essential Oil from Central Algeria

Cymbopogon schoenanthus (L.) Spreng . (Poaceae) is an aromatic plant whose aerial parts and rhizome produced an essential oil with pleasant odor. A chemical variability has been observed depending of the countries where the plant grows wild, including Algeria. The chemical compositions of 24 oil samples isolated from plants harvested in Central Algeria have been investigated, to evidence homogeneity or chemical variability within a given area of harvest. Twenty of these were dominated by cis‐ and trans‐p‐menth‐2‐en‐1‐ols (22.6 %±3.6 and 14.3 %±1.7, resp.) beside four atypical compositions. Otherwise, aerial parts and rhizomes produced similar essential oils. Lastly, a fair antimicrobial activity was measured against Staphylococcus aureus strain, while the antioxidant potential was low.     

Content of Fatty Acids and Phenolics in Coratina Olive Oil from Tunisia: Influence of Irrigation and Ripening

The quality indices and chemical composition of Coratina olive oil produced in the northern region of Tunisia were evaluated, to determine the effect of three different irrigation regimes of the trees on the olive oils. The olives were sampled at two different stages of maturity, the oils were extracted, and standard methods were used to analyze the composition and quality of the oils. The fatty‐acid contents and quality parameters were only slightly affected by the irrigation regime. The contents of palmitic, oleic, and linoleic acids were above 12, 72, and 8%, respectively, for the second harvest, regardless of the irrigation level of the olive trees. Parameters such as the α‐tocopherol content and the phenolic profile were found to be significantly affected by the harvesting time; however, inconsistent changes were observed for the irrigation regimes, especially for the oil of the second harvest. It was shown that the irrigation conditions of the olive trees as well as the harvesting time of the fruits gave rise to a diverse range of olive oils in Tunisia.     

Effects of growth regulators on fruit abscission in oil palm, Elaeis guineensis

By delaying harvest of fruit bunches of the oil palm Elaeis guineensis Jacq., an increase in their oil content can be obtained, but this is accompanied by increased harvesting costs and lower oil quality, as the number of detached fruit increases. Treatment of ripening bunches with auxins, gibberellic acid, or ethephon retards fruit abscission, and harvest can be delayed by up to 5 days without increase in the number of detached fruit. Indications are that oil yield might increase by more than 5% during this period, without change in harvesting costs or oil quality.     

Effects of timber harvest on river food webs: physical, chemical and biological responses

I compared physical, chemical and biological characteristics of nine rivers running through three timber harvest regimes to investigate the effects of land use on river ecosystems, to determine whether these corresponded to changes linked with downstream location, and to compare the response of different types of indicator variables. Physical variables changed with downstream location, but varied little with timber harvest. Most chemical variables increased strongly with timber harvest, but not with downstream location. Most biological variables did not vary systematically with either timber harvst or downstream location. Dissolved organic carbon did not vary with timber harvest or downstream location, but correlated positively with salmonid abundance. Nutrient manipulations revealed no general pattern of nutrient limitation with timber harvest or downstream location. The results suggest that chemical variables most reliably indicate timber harvest impact in these systems. The biological variables most relevant to human stakeholders were surprisingly insensitive to timber harvest, however, apparently because of decoupling from nutrient responses and unexpectedly weak responses by physical variables.     

木香薷精油提取最佳采收期的研究

采用测定生物量与精油提取相结合的方法来研究确定木香薷的最佳采收期。结果表明:霍山地区木香薷的最佳采收期在8月中旬。木香薷生物量的增长在前期主要表现为当年生小枝数的增加,而后期表现为当年生小枝重量的增加。从5月12日到8月17日,每100 g干重的当年生枝产精油量逐渐增加,而8月17日之后精油产量逐渐下降,以8月7日为最高达到1.62 g,得率为1.62%。     

Production of sophorolipids in high concentration from deproteinized whey and rapeseed oil in a two stage fed batch process using Candida bombicola ATCC 22214 and Cryptococcus curvatus ATCC 20509

High concentrations of 422 g sophorolipids l–1 were produced using a two-stage cultivation process: first deproteinized whey concentrate (DWC) containing 110 g lactose l–1 was used for cultivation of the yeast Cryptococcus curvatus ATCC 20509, resulting in 34 g dry weight l–1, 20 g single-cell oil l–1 and reducing the chemical oxygen demand (COD) from 159 g l–1 to 35 g oxygen l–1. Afterwards cells were disrupted by passing the cell suspension directly through a high pressure laboratory homogeniser. After autoclavation, the resulting crude cell extract containing the single-cell oil served as substrate for growth of Candida bombicola ATCC 22214 and for sophorolipid production in a second stage. When the single-cell oil was consumed, repeated feeding of 400 g rapeseed oil l–1 was started increasing the yield of sophorolipids to 422 g l–1. A simple technique for product isolation, sedimentation, could be used to harvest the crude sophorolipids. © Rapid Science Ltd. 1998     

The Effects of Solar Radiation on Plant Growth, Oil Yield and Oil Quality of Japanese Mint

Plants of Japanese mint (Mentha arvensis L. subsp. haplocalyxBriquet var. piperascens Holmes) were grown under 100, 64, 49and 28% conditions of prevailing radiation for 10 weeks, withharvests at 4, 6.8 and 10 weeks. Measurements were made on plantgrowth, yields of essential oil and chemical composition ofoil. The greatest morphological responses to increased shading intensitywere increases in stem length and leaf area. Little responseto shading was shown by mean relative growth rate (RGR) or meannet assimilation rate (NAR) while that of mean leaf area ratio(LAR) was marked. No significant differences in oil yield werefound among different treatments at the final harvest nor werethere great differences in amounts of menthol and menthone,two important constituents of Japanese mint oil. The experiments indicate that, within the experimental limitsimposed, Japanese mint tends to compensate in growth and oilproduction for shading effects. This work may also explain thedifferent and sometimes contradictory results reported in theliterature on the effects of shading on mint oil production     

Comparative chemical composition of the essential oils obtained by microwave-assisted hydrodistillation and hydrodistillation from Agrimonia pilosa LEDEB. Collected in three different regions of China

Conventional hydrodistillation (HD) and microwave-assisted hydrodistillation (MAHD) were performed to obtain the volatile oils of Agrimonia pilosa Ledeb. harvested in three different regions of China, which were subsequently characterized by GC-FID and GC/MS analyses. Compared with HD, MAHD was advantageous in terms of energy savings and extraction time (60 vs. 240?min for MAHD and HD, resp.). The chemical composition varied among the different oils obtained, and the variations in the contents of the main constituents of the oils were irregular. Hence, these variations affected both the quantity and composition of the oils. The oil yields (0.15-0.21%) were affected by the method of extraction and the region of harvest, with the maximum amount of oil obtained by MAHD for the plants collected in Hubei (HB) and the minimum yield obtained by HD for the plants from Zhejing (ZJ). Hexadecanoic acid constituted the major compound of the essential oils, with the highest content found in the oil obtained by HD for plants from HB (41.18%) and the lowest one found in the oil obtained by MAHD from plants from ZJ (11.83%). Microwave irradiation did not adversely affect the composition of the essential oils. The findings show that MAHD is a modern, green, and fast technology.     

Effect of soil sodicity on the growth,yield and chemical composition of groundnut (Arachis hypogaea Linn.)

Summary A replicated field experiment was conducted to study the effect of exchangeable sodium percentage (ESP) on the yield, chemical composition, protein and oil content and uptake of nutrients by groundnut (Arachis hypogaea Linn.) variety M-13. ESP over 15 delayed germination and emergence of flowers. There was continuous decrease in dry matter yield at 30 and 60 days of growth, grain and straw yield after harvest and protein, oil and kernel percent with increase in soil ESP. A 50 per cent reduction in groundnut yield was observed at an ESP of 20. Increasing soil ESP, increased Na and decreased K, Ca and N contents, but had no effect on the Mg, P, S, Fe, Mn, Zn and Cu contents of the plant. Sodium content of the plant increased, while potassium and nitrogen decreased with age of the plant. The uptake of all the nutrients decreased with increase in soil ESP. The results showed that groundnut is a relatively sensitive crop to soil sodicity.     

Black leaf streak of bananas in Fiji

Black leaf streak of bananas, caused by Mycosphaerella sp., prevented fruit of export quality forming and bunches maturing. Some infected leaves lived less than 50 days and were seldom retained until harvest. Maneb or benomyl applied in oil/water emulsions gave good control and benomyl was so effective that plants had ten leaves at harvest and some leaves survived for 245 days. Plants sprayed with maneb or benomyl flowered I month early. No benomyl residues were detected in the fruit exported to New Zealand. The control of black leaf streak by sprays containing oil has caused other leaf diseases to become more prevalent and the ensuing complex disease situation is discussed.