气质联用检测沉香燃烟粒相物中的挥发性成分

利用气质联用对沉香燃烟粒相物中的挥发性化合物进行定性及半定量检测,并对萃取溶剂、溶剂用量、振荡时间进行优化。最终选定二氯甲烷为萃取溶剂,溶剂用量为30 m L,振荡时间为30 min;对人工沉香和天然沉香燃烟粒相物谱图进行了分析,共鉴定出123种物质,主要为一些小分子挥发性物质、降解糖、单萜及含甲氧基的化合物,其中有26种物质具有各种香气特征的常用于食品香料的制备,在天然沉香燃烟中,26种具香气的物质所占鉴定物质总量的百分比高于人工沉香。     

<Emphasis Type="Italic">Cornus mas</Emphasis> (L.) Fruit as a Potential Source of Natural Health-Promoting Compounds: Physico-Chemical Characterisation of Bioactive Components

Interest in new sources of anti-inflammatory and antioxidant compounds has recently become a major research issue, with the cornelian cherry (Cornus mas L.) receiving particular attention for its significant amounts of phenolic compounds and vitamins, which exhibit a wide range of biological and pharmacological properties. This study was aimed at increasing knowledge regarding the cornelian cherry in Italy through the analysis of biologically active substances in the locally available genotype “Chieri”. Spectrophotometric methods were applied to evaluate antioxidant activity, total anthocyanin content and total polyphenolic content. Identification and quantification of the main phytochemical compounds (polyphenols, monoterpenes, organic acids and vitamin C) was performed via high performance liquid chromatography coupled to a diode array detector. C. mas extracts showed high levels of total soluble solids and low acidity. High amounts of phenolic secondary metabolites were observed, with particular reference to anthocyanins (134.71 mg_C3G/100 g_FW), which confer remarkable nutraceutical properties to the analysed samples. These results highlight the potential of C. mas fruits as a good source of natural antioxidants, suggesting their use as a functional food. Future studies should focus on identifying other specific phytochemical compounds and the genetic traits of local varieties in order to improve cornelian cherry cultivars for food and medicine production.     

The search for new natural herbicides – Strategic approaches for discovering fungal phytotoxins

Plant pathogens produce toxic metabolites which may play a role in affecting their plant hosts by the development of diseases. Such compounds present considerable potential as models for developing herbicides with new modes of action unrelated to those in current use. This study provides an overview on the chemical ecology of plant-pathogenic fungi interactions as a promising approach for discovering new molecules possessing herbicide activity, along with the main research strategies currently employed for the isolation and identification of such compounds. The steps involved in: a) isolating fungal phytotoxic metabolites; b) the factors affecting in vitro biosynthesis of phytotoxins, extraction and fractionation methods; c) the bioassay-guided fractionation procedure, and d) the bioassays most commonly used for monitoring isolation processes, are discussed.     

The phytotoxicity of insecticidal seed coatings and granular and spray soil treatments to grain yields in field experiments on the control of larvae of wheat bulb fly (Delia coarctata Fall.)

A simple statistical procedure has been derived to measure the direct effect of insecticides, particularly any phytotoxic effect, on cereal grain yields. Data from several years' field experiments on the use of insecticides to control larvae of the wheat bulb fly (Delia coarctata Fall.) (Diptera: Anthomyiidae) have been used to determine the ratio of (grain yield ÷ percentrage of undamaged shoots) for plots treated with an insecticide to (grain yield ÷ percentage of undamaged shoots) for untreated plots. A ratio < 1 indicated that the insecticide was phytotoxic; a ratio > 1 suggested that the compound was phytostimulant. The ratios of all the insecticidal seed coatings and soil treatments of granules and sprays which were tested in the field experiments have been measured. The ratios for all insecticides (apart from fonofos microencapsulated seed coating at one site in 1974–1975) were <1. The phytotoxicity of the insecticides was found to vary between years. Insecticidal soil treatments (granules and sprays) seemed to be as phytotoxic as seed coatings. Synthetic pyrethroid seed coatings were slightly less phytotoxic than organophosphorus seed coatings. In field experiments on the control of wheat bulb fly larvae by insecticides, phytotoxicity has usually been estimated by a subjective system of scoring plots visually before larval invasion of plants. This method was compared with the objective method of determining pesticide/untreated (or P/U) ratios. Visual scoring appears to be the more efficient method of determining the most phytotoxic insecticide, whereas the least phytotoxic insecticide is determined more accurately by the method of P/U ratios.     

Allelopathic Effects of Some Volatile Substances from the Tomato Plant

Summary

The allelopathic effects of chemical substances released from the tomato plant (Lycopersicon esculentum Mill.) were investigated on various receptor plants. Bioassays under controlled conditions in a growth chamber showed that germination and seedling growth of Lactuca sativa and growth of Vitis were reduced when grown near tomato plants. It was also observed that when plants were grown in a U-tube pot with tomato plant, the tomato roots excreted allelochemicals that inhibit growth of tested species. To identify the phytotoxic compounds from tomato plant, a GC/MS method was employed. Forty compounds, such as trans-2-hexenal, a-terpineol, linalool, phenylace-taldehyde, methylsalicylic acid and tetradecanoic acid were identified from the essential oil of tomato plants. The volatile substances from leaves inhibited seed germination and seedling growth of receptor plants in laboratory tests. Inhibitory response varied with the concentration of compounds. These findings suggest that the tomato plant may have an interesting allelopathic potential.     

Advances in the identification and agrochemical importance of sesquiterpenoids from Bulnesia sarmientoi essential oil

Bulnesia sarmientoi Lorentz ex Griseb volatile oil was characterized by GC × GC-TOF-MS analysis. Major components were guaiol and bulnesol, followed by hanamyol. The enhanced sensitivity and superior resolution of GC × GC resulted in the identification of thus-far unreported oil constituents as β-guaiene, guaioxide, elemol, germacrene-B, eudesm-5-en-11-ol, γ-eudesmol, α-eudesmol and (−)-hanamyol. The insecticidal effect of B. sarmientoi oil and its main constituents (guaiol, bulnesol and hanamyol) on Spodoptera littoralis, Rhopalosiphum padi and Myzus persicae was studied. Guaiol affected the aphids in a dose-response fashion, showing low efficiency, while bulnesol and hanamyol were inactive. Both the oil and its constituents were also assayed for antifungal action against Fusarium spp. and phytotoxicity to Lactuca sativa. Among the pure compounds tested, bulnesol had a low-moderate effect on Fusarium moniliforme while hanamyol had a strong effect on Fusarium solani. Neither the oil nor the tested compounds affected L. sativa germination or radicle length, indicating that B. sarmientoi is not phytotoxic.     

Cyclic Bis-1,3-dialkylpyridiniums from the Sponge Haliclona sp.

Eight novel cyclic bis-1,3-dialkylpyridiniums, as well as two known compounds from the cyclostellettamine class, were isolated from the sponge Haliclona sp. from Korea. Structures of these novel compounds were determined using combined NMR and FAB-MS/MS analyses. Several of these compounds exhibited moderate cytotoxic and antibacterial activities against A549 cell-line and Gram-positive strains, respectively. The structure-activity relationships of cyclostellettamines are discussed based on their bioactivities.     

Antiviral lead compounds from marine sponges

Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Several of them have successfully been approved as antiviral agents for clinical use or have been advanced to the late stages of clinical trials. Most of these drugs are used for the treatment of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). The most important antiviral lead of marine origin reported thus far is nucleoside Ara-A (vidarabine) isolated from sponge Tethya crypta. It inhibits viral DNA polymerase and DNA synthesis of herpes, vaccinica and varicella zoster viruses. However due to the discovery of new types of viruses and emergence of drug resistant strains, it is necessary to develop new antiviral lead compounds continuously. Several sponge derived antiviral lead compounds which are hoped to be developed as future drugs are discussed in this review. Supply problems are usually the major bottleneck to the development of these compounds as drugs during clinical trials. However advances in the field of metagenomics and high throughput microbial cultivation has raised the possibility that these techniques could lead to the cost-effective large scale production of such compounds. Perspectives on biotechnological methods with respect to marine drug development are also discussed.     

Chemical composition of the essential oil of Artemisia absinthium growing wild in Iran

Studies were conducted to investigate the composition of essential oil of wormwood (Artemisia absinthium L.) growing wild in Iran. The wormwood aerial parts were harvested in full blooming time from an area between Deylaman and Asiabar villages, at Alborz altitudes in Guilan province in September 2005. Aerial parts were dried at shade (room temperature) for several days and their essential oil was extracted by hydrodistillation method in a Clevenger apparatus and analyzed by GC/MS. Results showed that essential oil yield was 1.3%. Twenty eight components representing 93.3% of the oil were identified, which were mostly monoterpenes. beta-pinene and beta-thujone were the main components, which their contents were 23.8 and 18.6% respectively. The largest part of the essential oil was formed by hydrocarbon monoterpenes (47.8%). The results proved that chemotype of the studied wormwood essential oil was specific and different from other wormwood essential oil chemotypes, which have been reported so far.     

Biomedical Compounds from Marine organisms

The Ocean, which is called the ‘mother of origin of life’, is also the source of structurally unique natural products that are mainly accumulated in living organisms. Several of these compounds show pharmacological activities and are helpful for the invention and discovery of bioactive compounds, primarily for deadly diseases like cancer, acquired immuno-deficiency syndrome (AIDS), arthritis, etc., while other compounds have been developed as analgesics or to treat inflammation, etc. The life-saving drugs are mainly found abundantly in microorganisms, algae and invertebrates, while they are scarce in vertebrates. Modern technologies have opened vast areas of research for the extraction of biomedical compounds from oceans and seas.     

Evaluation of spray programmes for the management of leaf spot incited by Pseudomonas syringae pv. syringae on tomato cv. Cuore di bue

Four experimental trials were carried out in northern Italy under greenhouse conditions against bacterial leaf spot of tomato, incited by Pseudomonas syringae pv. syringae, a disease recently observed in the country. The efficacy of spray programmes, based on the use of several copper-based compounds, acibenzolar-S-methyl, fosetyl Al and two biological control agents, Bacillus subtilis strain QST 713 and Pseudomonas chlororaphis MA 342, was tested. The best results were obtained with the alternation of copper oxychloride, used alone or in mixture with acibenzolar-S-methyl, with acibenzolar-S-methyl, applied for a total of two sprays. Acibenzolar-S-methyl applied alone was also effective. However, due to its possible slight phytotoxic effect, observed in our case in one trial, strategies relying on a limited number of its application are preferred. The efficacy of acibenzolar-S-methyl is higher under lower inoculum conditions. Among the tested copper-based fungicides, copper oxychloride provided the best and most consistent results, with no or limited phytotoxicity. Other copper compounds were much less effective and sometimes caused a reduction in plant height. The disease suppression achieved with B. subtilis strain QST 713 was only partial, while P. chlororaphis was not effective. The advantages of programmes based on rotation of copper compounds and acibenzolar-S-methyl are discussed.     

茶树挥发性萜类物质及其糖苷化合物生物合成的研究进展

挥发性单萜（C₁₀）与倍半萜（C₁₅）,常具有宜人的花果香气。茶鲜叶中此类物质的种类及其糖苷化合物的含量和水解对成品茶的香气香型有重要影响。就可能影响茶树挥发性萜类物质及其糖苷化合物合成途径中的限速反应和相关的酶进行综述,认为1-脱氧-D-木酮糖-5-磷酸还原异构酶（DXR）和羟甲基戊二酰辅酶A还原酶（HMGR）是影响萜类代谢前体异戊烯基焦磷酸（IPP）及二甲烯丙基焦磷酸（DMAPP）的限速酶。单萜和倍半萜合成酶是挥发性萜类化合物生物合成途径中的关键酶。此外,糖基转移酶可能与茶鲜叶中糖苷态萜类香气化合物的合成和积累有关。糖苷水解酶则催化茶鲜叶中糖苷态香气物质的水解,导致香气物质的释放。调节相关基因的表达,将有可能控制萜类代谢流向挥发性萜类合成分支。本文还讨论了影响茶叶香气品质的其他因素,如茶树品种、栽培环境,以及加工方法等。     

Chemical composition and anti-fungal properties of the essential oils and crude extracts of Orthosiphon stamineus Benth

The hydrodistilled essential leaves and stems oils of Orthosiphon stamineus Benth were analysed by GC–MS/MS. Sixty nine compounds representing 97.6 and 97.4% of the total leaves and stems oils, respectively were identified, of which β-caryophyllene (24.0 and 35.1%), α-humulene (14.2 and 18.4%), β-elemene (11.1 and 8.5%), 1-octen-3-ol (8.2 and 7.0%), β-bourbonene (3.4 and 3.0%), β-pinene (2.1 and 1.7%), caryophyllene oxide (1.6 and 2.2%), camphene (1.6 and 1.3%) and limonene (1.2 and 1.1%) were the major compounds. Thus, the monoterpenes and sesquiterpenes were the predominant portions of the oils. Essential oils and methanol extract of O. stamineus and the derived fractions of hexane, chloroform, and ethyl acetate were tested for anti-fungal activity, which was determined by disc diffusion and minimum inhibitory concentration (MIC) determination methods. The oils, methanol extract and derived fractions of methanol extract displayed great potential of anti-fungal activity as a mycelial growth inhibitor against the tested phytopathogenic fungi such as Botrytis cinerea, Rhizoctonia solani, Fusarium solani, Colletotricum capsici and Phytophthora capsici, in the range of 49.3–70.3% and minimum inhibitory concentration ranging from 500 to 1000 μg/ml.     

Recent Advances and Applications of Experimental Technologies in Marine Natural Product Research

Marine natural products are a rich source of novel and biologically active compounds. The number of identified marine natural compounds has grown 20% over the last five years from 2009 to 2013. Several challenges, including sample collection and structure elucidation, have limited the development of this research field. Nonetheless, new approaches, such as sampling strategies for organisms from extreme ocean environments, nanoscale NMR and computational chemistry for structural determination, are now available to overcome the barriers. In this review, we highlight the experimental technology innovations in the field of marine natural products, which in our view will lead to the development of many new drugs in the future.     

Preliminary evaluation of phosphorous acid,fosetyl-A1 and metalaxyl for controlling Phytophthora cambivora on almond and cherry

Aqueous solutions of 1·0 or 10·0 g a.i/l of phosphorous acid (H₃PO₃) neutralized with KOH and applied as a foliar spray or soil drench inhibited the development of stem lesions on potted almond and cherry plants inoculated with Phytophthora cambivora and in most cases were effective as either 0·25 g a.i./l metalaxyl or 3·2 g a.i./l fosetyl-A1 drenches. Sprays or drenches of 10 g a.i. H₃PO₃/l were phytotoxic to potted almonds causing marginal leaf scorch, leaf drop and brown necrotic lesions on young shoots. Foliar sprays of 1 g a.i. H₃PO₃/l or drenches of 20 g a.i. H₃PO₃/l were not phytotoxic to 4-year-old Mahaleb cherry trees and restricted lesions caused by P. cambivora for up to 17 weeks after application. A 10% neutralized solution of H₃PO₃ injected directly into the trunk of cherry trees inhibited P. cambivora lesions for a similar period but the treatment was initially phytotoxic.     

Effect of drying temperature on essential oil content and composition of sweet wormwood (Artemisia annua) growing wild in Iran

Studies were conducted to show the effect of different temperatures in the drying process on the amount and quality of essential oils of sweet wormwood (Artemisia annua L.). The sweet wormwood aerial parts were harvested in full blooming time from an area around the Siahkal city in north of Iran in September 2005. In order to complete drying, the aerial parts were placed at shade (room temperature) and in oven at 35, 45, 55 and 65 degrees C temperatures. The aerial parts essential oil was extracted by hydrodistillation in a Clevenger apparatus and analyzed by GC/MS. Results showed that higher drying temperatures decreased the essential oil content, from 1.12% (room temperature) 0.88% (35 degrees C), 0.55% (45 degrees C) to 0.50% (55 degrees C) and 0.37% (65 degrees C). Thirty-five components were determined in essential oils, which were mostly monoterpenes. The drying temperatures had a significant effect on the essential oils composition and proportion of the various components, as when the temperature increased, the monoterpenes content gradually decreased and vice versa for sesquiterpenes. The major components were artemisia ketone and 1, 8 cineol for room and 45 degrees C; artemisia ketone, 1, 8 cineol and camphor for 35 and 55 degrees C and beta-caryophyllene and germacrene D for 65 degrees C temperatures.     

Inhibition of potato sprout growth by carvone enantiomers and their bioconversion in sprouts

Summary The monoterpenes (R)-(−)-carvone and (S)-(+)-carvone inhibited sprout growth in a model system consisting of sprouts growing from potato eye pieces. The sprout tissue was not necrotic after carvone treatment and the inhibition was reversible, since after treatment the sprouts showed regrowth either by continued top growth or by branching. However, the effect of both isomers on sprout growth differed, and (S)-(+)-carvone inhibited the elongation of the sprouts sooner than did (R)-(−)-carvone. This might be explained by a faster uptake of the former, since the concentration of (S)-(+)-carvone and its derivatives was twice as high during the first 4 days compared with (R)-(−)-carvone-treated sprouts. The sprouts were able to reduce (R)-(−)-carvone mainly into neodihydrocarveol, and (S)-(+)-carvone into neoisodihydrocarveol; in addition hydroxylated compounds were also detected. To whom correspondence should be addressed     

Amino Alcohols from the Ascidian Pseudodistoma sp

Seven new amino alcohol compounds, pseudoaminols A–G (1–7), were isolated from the ascidian Pseudodistoma sp. collected off the coast of Chuja-do, Korea. Structures of these new compounds were determined by analysis of the spectroscopic data and from chemical conversion. The presence of an N-carboxymethyl group in two of the new compounds (6 and 7) is unprecedented among amino alcohols. Several of these compounds exhibited moderate antimicrobial activity and cytotoxicity, as well as weak inhibitory activity toward Na⁺/K⁺-ATPase.     

The effectiveness of carbamate and copper compounds in the control of Cercospora beticola Sacc. and their effects on yield and quality composition of autumn sown sugar beets

The fungicidal effectiveness of Zn-carbamate and copper compounds and their effects on yield and quality composition of autumn-sown beets were investigated under field conditions in a subtropical area. The two kinds of compounds — at their specific optimal treatment combinations — were equally effective in their fungicidal action and in leaf preservation. Weekly applications were required in the warmer part of the growing season for optimal results; however, during the cooler, earlier period triweekly applications were sufficient. Sprinkler pre-irrigation was essential for effective control by the fungicide-treatments. Zn-carbamate significantly exceeded the two copper compounds in sucrose storage (by 1395 kg/ha). This was the result of a less phytotoxic — respiration enhancement — effect. Beaurdice, a metallic Cu-compound, exerted the most detrimental effect. The optimal treatment for sucrose storage increased: (a) the total sucrose by 5170 kg up to 18,430 kg/ha, (b) the daily net storage rate of sucrose by 311.4%, and (c) sucrose/m³ of water by 610–710 g. The effective treatments considerably improved the technological value of the beet by: (a) increasing the juice purity by 4.7% to 91.7%, (b) decreasing the sol. ash and sol. N ratios and (c) maintaining the sucrose concentration at the same, or slightly higher, level throughout the entire experimental season. It was shown that the Cu-ions restricted the sol. ash concentration in the beet by interfering with the uptake of the mineral elements or by enhancing their incorporation.     

Effects of alfalfa leaf extracts and phenolic allelochemicals on early seedling growth and root morphology of alfalfa and barnyard grass

Alfalfa (Medicago sativa L.) plants contain water-soluble substances that are autotoxic as well as allelopathic to other plants. Laboratory experimentation through a petri dish assay with imbibed seeds was conducted to evaluate the phytotoxic effects of alfalfa cv. “Vernal” leaf extracts, coumarin, trans-cinnamic acid, o-coumaric acid, and hydro-cinnamic acid on the seedling growth and anatomical responses of 6 day-old alfalfa and barnyard grass. With increasing concentration, the alfalfa leaf extracts significantly reduced root lengths of alfalfa and barnyard grass (Echinochloa crus-galli, Beauv. var. oryzicola Ohwi). Coumarin, trans-cinnamic acid, o-coumaric acid, and hydro-cinnamic acid at 10⁻⁴ M significantly reduced root lengths of alfalfa and barnyard grass. The root systems, especially root tips of alfalfa, were stunted and swollen by the aqueous alfalfa leaf extracts at 30 g l⁻¹ and coumarin at 10⁻³ M. This research suggests that alfalfa plant extracts significantly affected root growth and morphological differentiation of susceptible plants, resulting in reduction of their biomass in the presence of either autotoxic or allelopathic compounds. The results may have value in enabling weed control based on natural plant extracts.