The role of volatile semiochemicals in mediating host location and selection by nuisance and disease-transmitting cattle flies

The role of volatile semiochemicals in mediating the location and selection within herds of Holstein-Friesian heifers by nuisance and disease-transmitting cattle flies was investigated using coupled gas chromatography-electrophysiology (GC-EAG), coupled gas chromatography-mass spectrometry (GC-MS), electrophysiology (EAG), laboratory behaviour and field studies. Using volatile extracts collected by air entrainment from heifers in the Netherlands, a number of active peaks were located by coupled GC-EAG for Musca autumnalis (de Geer) (Diptera: Muscidae) and Haematobia irritans (L.) (Diptera: Muscidae). Volatile samples were also collected from two heifers in Denmark shown in previous counting experiments to differ significantly in their fly loads. Coupled GC-EAG using Ha. irritans antennae revealed differences in the EAG response to the samples, with additional EAG activity in the sample collected from the heifer with the lower fly load. To identify more EAG active compounds, volatiles were also collected from 48-h-old urine by air entrainment. In total, 23 compounds were located and identified by coupled GC-EAG and GC-MS. Further electrophysiological testing of these compounds with five fly species [M. autumnalis, Ha. irritans, Hydrotaea irritans (L.) (Diptera: Muscidae), Stomoxys calcitrans (L.) (Diptera: Musicidae) and Wohlfahrtia magnifica (Schiner) (Diptera: Sarcophagidae)] showed that only some of the compounds were physiologically active across the range of flies tested. These included 1-octen-3-ol, 6-methyl-5-hepten-2-one, (Z)-3-hexen-1-ol, naphthalene, and all EAG active compounds identified from urine. Compounds showing significant EAG activity were tested for behavioural activity using a wind-tunnel designed for measuring upwind flight behaviour. At certain concentrations, 1-octen-3-ol, 6-methyl-5-hepten-2-one and 3-octanol increased upwind flight, whereas naphthalene, propyl butanoate and linalool reduced upwind flight. In field studies using small herds of heifers ranked according to their fly load, individual slow-release formulations of 1-octen-3-ol and 6-methyl-5-hepten-2-one, when applied to low and high fly loading heifers, reduced fly loads on these individuals. This study provides evidence for the hypothesis that the natural differential attractiveness within herds of Holstein-Freisian heifers, i.e. a single host species, for cattle flies is partly due to differences in volatile semiochemicals emitted from the host. It is suggested that this phenomenon applies to other vertebrate host species and their associated insect pests.     

蓝柄丽齿菌的化学成分

从担子菌亚门蓝柄丽齿菌(Calodon suaveolens)中首次分离得到8个化合物,通过波谱学技术并借助必要的化学方法最终确定结构,它们是：(22E,24R)-麦角甾-7,22-二烯-3β-醇(1),(22E,24R)-5α,8α-过氧麦角甾-6,22-二烯．3β-醇(2),(22E,24R)-麦角甾．5,7,22-三烯-3β-醇(3),(22E,24R)-3β-羟基麦角甾-5,22-二烯-7-酮(4),对羟基苯甲酸(5),尿嘧啶(6),polyozellin(7),(4E,BE）-2-N-(2’-羟基棕榈酰)-1-O-β-D-吡喃葡萄糖基-9-甲基-4,8-sphingadienine(8)。     

Rapid identification of microbial VOCs from tobacco molds using closed-loop stripping and gas chromatography/time-of-flight mass spectrometry

Several microbial volatile organic compounds (MVOCs) that can serve as potential chemical markers for microbial contamination in tobacco have been identified. Four different fungal species, Aspergillus niger (AN), A. ornatus (AO), Pencillium chrysogenum (PC) and Rhizopus stolonifer (RS), commonly reported in moldy tobacco were cultured and screened for MVOCs. Because the MVOCs emitted by a microbial species are substrate specific, the fungal strains were separately grown on potato dextrose agar (PDA) and tobacco products. MVOCs from the mold cultures grown on PDA and tobacco products were extracted using closed-loop stripping analysis (CLSA) and identified by gas chromatography/time-of-flight mass spectrometry (GC/TOF-MS). Some of the prominent tobacco mold markers identified by this method include: 1-octen-3-ol; 2-octen-1-ol; 2-methyl-1-butanol; 3-methyl-1-butanol; 1-octene and 2-pentanone. In particular, 1-octen-3-ol was detected in all the mold cultures and moldy tobacco samples analyzed. Olfactory evaluation of 1-octen-3-ol indicated a characteristic musty odor and the odor threshold was determined to be approximately 200 ng/ml. The limits of detection for 1-octen-3-ol using GC/TOF-MS and GC/mass selective detector (MSD) in the full-scan mode and selected ion monitoring (SIM) mode were investigated. The CLSA-GC/TOF-MS demonstrates a fast, sensitive and semi-quantitative analytical technique for screening tobacco materials for the presence of mold via chemical markers of microbial contamination.     

Detection and mass spectrometric characterization of novel long-term dehydrochloromethyltestosterone metabolites in human urine

The biotransformation of dehydrochloromethyltestosterone (DHCMT, 4-chloro-17β-hydroxy,17α-methylandrosta-1,4-dien-3-one) in man was studied with the aim to discover long-term metabolites valuable for the antidoping analysis. Having applied a high performance liquid chromatography for the fractionation of urinary extract obtained from the pool of several DHCMT positive urines, about 50 metabolites were found. Most of these metabolites were included in the GC-MS/MS screening method, which was subsequently applied to analyze the post-administration and routine doping control samples. As a result of this study, 6 new long-term metabolites were identified tentatively characterized using GC-MS and GC-MS/MS as 4-chloro-17α-methyl-5β-androstan-3α,16,17β-triol (M1), 4-chloro-18-nor-17β-hydroxymethyl,17α-methyl-5β-androsta-1,13-dien-3α-ol (M2), 4-chloro-18-nor-17β-hydroxymethyl,17α-methyl-5β-androst-13-en-3α-ol (M3), its epimer 4-chloro-18-nor-17α-hydroxymethyl,17β-methyl-5β-androst-13-en-3α-ol, 4-chloro-18-nor-17β-hydroxymethyl,17α-methylandrosta-4,13-dien-3α-ol (M4) and its epimer 4-chloro-18-nor-17α-hydroxymethyl,17β-methylandrosta-4,13-dien-3α-ol. The most long-term metabolite M3 was shown to be superior in the majority of cases to the other known DHCMT metabolites, such as 4-chloro-18-nor-17β-hydroxymethyl,17α-methylandrosta-1,4,13-trien-3-one and 4-chloro-3α,6β,17β-trihydroxy-17α-methyl-5β-androst-1-en-16-one.     

Chemical synthesis, spectral properties, and chromatography of 4alpha-methyl and 4beta-methyl isomers of (24R)-24-ethyl-5alpha-cholestan-3beta-ol and (24S)-24-ethyl-cholesta-5,22-dien-3beta-ol.

Described herein are chemical syntheses of the following compounds: 4-methyl-(24S)-24-ethyl-cholesta-4,22-dien-3-one, 4,4-dimethyl-(24S)-24-ethyl-cholesta-5,22-dien-3-one, 4beta-methyl-(24R)-24-ethyl-5alpha-cholestan-3beta-ol, 4alpha-methyl-(24R)-24-ethyl-5alpha-cholestan-3beta-ol, 4alpha-methyl-(24S)-24-ethyl-5alpha-cholest-22-en-3beta-ol, 4-methyl-6beta-bromo-(24S)-24-ethyl-cholesta-4,22-dien-3-one, 4alpha-methyl-(24S)-24-ethyl-cholesta-5,22-dien-3beta-ol, 4alpha,5alpha-epoxy-(24S)-24-ethyl-cholesta-4,22-dien-3beta-yl acetate, 4beta-methyl-(24S)-24-ethyl-cholest-22-en-3beta,5alpha-diol, 4beta-methyl-5alpha-hydroxy-(24S)-24-ethyl-cholest-22-en-3beta-yl acetate, 4beta-methyl-(24S)-24-ethyl-cholesta-5,22-dien-3beta-yl acetate and 4beta-methyl-(24S)-24-ethyl-cholesta-5,22-dien-3beta-ol. Chromatographic, nuclear magnetic resonance, and mass spectral data are presented for the compounds under consideration.     

Electroantennogram responses of the stable fly, Stomoxys calcitrans, to components of host odour

Abstract. Electroantennograms (EAGs) were recorded from laboratory-reared male and female Stomoxys calcitrans (L.) in response to a range of synthetic chemicals known to be electrophysiologically-active for other biting flies. Of the eight compounds initially tested, only two - 1-octen-3-ol and 3-methylphenol - consistently elicited larger electroantennograms (EAGs) than did control treatments; 1-octen-3-ol was the most potent. EAG recovery time was inversely correlated with EAG amplitude. EAGs recorded with primary C₂-C₁₂ carbon chain-length primary aliphatic alcohols peaked at octan-1–ol with pentan-1-ol, hexan-1-ol and heptan-1-ol also eliciting EAG responses significantly larger than the controls. When different C₈ carbon chain compounds and nonane were tested: 1-octen-3-ol elicited the largest EAGs followed by, in decreasing activity, octan-1-ol, 1-bromooctane, octan-3-ol, octanal, 2-octanone, octanoic acid and nonane. The EAG response of 1-octen-3-ol increased sigmoidally with dose, with the threshold at between 2 and 20 ng, and the peak response at 200 μg on filter paper. EAGs larger than control were also elicited by entrained ox odour and ox breath. The behavioural implications are discussed.     

Antiprogestational agents. The synthesis of 7-alkyl steroidal ketones with anti-implantational and antidecidual activity

A series of 7α- and 7β- alkyl derivatives of steroidal 4-en- and 5-en-3-ones were prepared by 1,6-conjugate addition of organocopper reagents to various steroidal 4,6-dien-3-ones of the androstane, estrane and gonane series. Biological study of these and related compounds revealed that 17β-hydroxy-7α-methyl-5-androsten-3-one (2), 17β-hydroxy-7α-methyl-5-estren-3-one acetate and 17β-hydroxy-7α-methyl-4-estren-3-one acetate had significant anti-implantational and antidecidual activities. The contragestative effects were associated with the latter antihormonal properties, and not with the androgenicity of these compounds.     

SDE-GC-MS法分析三种虫生真菌菌丝中挥发性成分

采用同时蒸馏萃取-气相色谱质谱联用（SDE-GC-MS）的方法分析了蝉拟青霉、拟细羽束梗孢、根足被毛孢菌丝的挥发性成分,从中分别鉴定出44、28和19种化合物,它们主要为萜类化合物、芳香族化合物、醇类、烷烃类、酯类和醛类。成分比较发现,3种虫生真菌挥发性物质中有3种主要共有成分,分别为丁羟基甲苯、1-辛烯-3-醇、苯乙醛。除共有成分外,它们各自都有大量特有成分,其中蝉拟青霉主要有5-甲基-2-呋喃-乙酸酯、反式-2,4-癸二烯醛、长叶烯等;拟细羽束梗孢主要有5-羟基-2-癸烯酸-δ-内酯、2,4-二甲基-恶唑、苯酚、β-榄香烯等;根足被毛孢主要有3,4,5-三甲基-苯甲醛、1,3-二甲基-3,4,5,6-四氢化-2(1H)嘧啶、顺式-2-羟基-1-（羟甲基）-9-十八碳一烯酸乙酯。     

木荷花挥发性成分的GC-MS分析

采用无水乙醚超声萃取得到新鲜木荷(Schima superba)花浸膏提取物,顶空固相微萃取富集挥发性成分,气相色谱-质谱联用仪分析,归一化法计算各组分的相对含量.鉴定出挥发性化合物中的51个成分,约占相对总含量的99%;挥发性成分中含氧化合物的含量超过93%,其中主要的化合物及其相对含量为酮代异佛尔酮(26.33%)、氧化芳樟醇(19.53%)、环氧芳樟醇(8.80%)、3,7-二甲基-2,6-辛二烯-1-醇(8.23%)、白藜芦素(7.89%)、4-羟基3,5,5-三甲基-2-环己烯-1-酮(6.54%)、2,6,6-三甲基-1,4-环己二酮(4.06%)、苯乙醇(2.17%)、2-甲基-2-壬烯-1-醇(2.04%)等.     

雌性中缅树鼩繁殖期尿液的挥发性成分分析

正动物化学通讯包含信号发出者、化学信号、信号接收者三要素。尿液、粪便及特化腺分泌物是哺乳动物的主要气味源,由醇、烷烃、酸、酯、肽、蛋白质等组成,且其化学成分较为复杂(Novotny et al.,1999;Zhao and Wang,2010;Zhang and Zhang,2011)。尿液中化学信号发挥着极为重要作用,可以编码多种信息,如编码身体质量     

Volatile compounds of endophyte-free and infected tall fescue (Festuca arundinacea Schreb.).

Volatile compounds produced by intact plants and ground leaf tissue from endophyte-infected (E+) and endophyte-free (E-) tall fescue (Festuca arundinacea Schreb.) were collected by a purge-and-trap procedure and analyzed by gas chromatography/mass spectrometry The volatile compound profile from ground leaf tissue was similar between E+ and E- clonal plants; however, the sheaths of E+ clonal plants produced higher levels of 1-octen-3-ol, a characteristic volatile compound derived from lipid peroxidation in fungi, which was absent in E- clonal plants. Intact plants produced fewer volatiles than macerated leaves. At 25 degrees C, (Z)-3-hexen-1-ol acetate was the most abundant compound, accounting for 77 and 89% of the total volatile emission from E+ and E- plants, respectively. Higher temperature (32 degrees C) significantly reduced the production of (Z)-3-hexen-1-ol acetate. Nonanal was the most abundant compound at 32 degrees C accounting for 52 and 45% of the total volatile emission from E+ and E- plants. Treatment of E+ and E- plants with jasmonic acid (JA) dramatically altered the volatile compound profile. The levels of (E)-beta-ocimene increased more than 200-fold and accounted for at least 43% of the total volatile emission. Although the presence of endophyte resulted in some qualitative and quantitative differences in the production of volatile compounds, they are unlikely to account for the differences in insect resistance between E+ and E- plants. Nevertheless, the production of a unique spectrum of volatiles after JA treatment may represent a significant plant-based defense response in tall fescue that is independent of endophyte.     

Fungal volatiles as indicators of food and feeds spoilage.

Fungal growth leads to spoilage of food and animal feeds and to formation of mycotoxins and potentially allergenic spores. Fungi produce volatile compounds, during both primary and secondary metabolism, which can be used for detection and identification. Fungal volatiles from mainly Aspergillus, Fusarium, and Penicillium have been characterized with gas chromatography, mass spectrometry, and sensory analysis. Common volatiles are 2-methyl-1-propanol, 3-methyl-1-butanol, 1-octen-3-ol, 3-octanone, 3-methylfuran, ethyl acetate, and the malodorous 2-methyl-isoborneol and geosmin. Volatile sesquiterpenes can be used for taxonomic classification and species identification in Penicillium, as well as to indicate mycotoxin formation in Fusarium and Aspergillus. Developments in sensor technology have led to the construction of "electronic noses" (volatile compound mappers). Exposure of different nonspecific sensors to volatile compounds produces characteristic electrical signals. These are collected by a computer and processed by multivariate statistical methods or in an artificial neural network (ANN). Such systems can grade cereal grain with regard to presence of molds as efficiently as sensory panels evaluating grain odor. Volatile compound mapping can also be used to predict levels of ergosterol and fungal colony-forming units in grain. Further developments should make it possible to detect individual fungal species as well as the degree of mycotoxin contamination of food and animal feeds.     

Antennal and behavioral responses of Cis boleti to fungal odor of Trametes gibbosa

Cis boleti (Coleoptera: Ciidae) preferentially colonizes fungi from the genus Trametes that are known as important wood decomposers. The aim of our research was to investigate if C. boleti uses the chemical volatile composition of its fungal host, Trametes gibbosa, as a key attraction factor. Therefore, the T. gibbosa fruiting body volatiles were analysed by using gas chromatography-mass spectrometry, with parallel electroantennographic detection (GC-MS/EAD) using adults of C. boleti. Furthermore, we examined the behavioral responses of C. boleti to the T. gibbosa volatile compounds. The dominant component of the T. gibbosa fruiting body bouquet was 1-octen-3-ol. Other volatiles, like the aldehydes hexanal, nonanal, and (E,E)-2,4-decadienal and the terpene alpha-bisabolol, were present in minor quantities. 1-Octen-3-ol was released with a ratio of the (R)- and (S)-enantiomers of 93:7, respectively. Electroantennography (EAG) employing C. boleti antennae yielded consistently dominant responses to 1-octen-3-ol. GC-EAD and EAG responses to pure standard compounds showed that C. boleti also perceived other host fungal volatiles. A highly significant attraction to 1-octen-3-ol was observed in behavioral tests. Female beetles were significantly attracted to the (S)-(+)- enantiomer at 10 times lower doses than male beetles. Our finding is the first direct proof that ciid beetles use 1-octen-3-ol as a key cue for host finding.     

非洲隔囊蚁巢伞的化学成分研究(英文)

从肯尼亚安波塞利产的隔囊蚁巢伞(Termitomyces schimperi)子实体中分离得到8个已知化合物,通过波谱方法鉴定它们的结构为(22E,24R)-麦角甾-5,7,22-三烯-3β-醇(1),(3β,5α,9α-三羟基麦角甾-7,22-二烯-6-酮(2),5α,8α-过氧-(22E,24R)-麦角甾-6,22-二烯-3β-醇(3),麦角甾-4,6,8(14),22-四烯-3-酮(4),D-阿拉伯糖醇(5),D-半乳糖醇(6),脑苷脂B(7)和脑苷脂D(8)。所有化合物均首次从该真菌中分离得到。     

Production of malodorous steroids from androsta-5,16-dienes and androsta-4,16-dienes by Corynebacteria and other human axillary bacteria

The biotransformations of a number of steroids, chiefly 5,6,16,17-tetradehydro-androstanes, are reported. The strains investigated were Corynebacteria sp. G38, G40, G41, B, Brevis sp. CW5 and Micrococcus sp. M-DH2. Corynebacterium sp. G41 proved remarkably efficient in effecting oxidative isomerisation of 5-ene-3-sterols into the corresponding 4-en-3-ones. The main biochemical reactions involved were oxidation at C-3; no reduction processes were observed. Conversions of 3β-sterols into the C-3 oxo-steroids were high, but were correspondingly low for the 3-sterol epimers. Androsta-4,16-dien-3-one and 5β-androsta-16-en-3-one are crucial to the formation of malodour. The rate of formation of these compounds was measured over 72 h incubation periods using three substrates: androsta-5,16-dien-3β-ol, androsta-4,16-dien-3β-ol and androsta-5,16-dien-3-one. Induction studies of the transformation of the androsta-5,16-dien-3β-ol into the very odorous compound androsta-4,16-dien-3-one showed that cells incubated with a mixture of antibiotics displayed the same extent of biotransformation as normal cells if the concentration of antibiotic was low (1, 3, 5 and 7 μg/ml), although at concentrations higher than 10 μg/ml, biotransformation yields were reduced. Pre-incubation with a 3β-fluoro-steroid inhibited the formation of the odorous androsta-4,16-dien-3-one.     

粤东产重瓣臭茉莉挥发油化学成分的GC-MS分析

采用水蒸气蒸馏法对粤东产重瓣臭茉莉(Clerodendrum chinense (Lour.) Merr.)挥发油进行提取, 并运用GC-MS对其成分进行分析和鉴定。结果分离出31个峰, 确定了31种化合物, 按峰面积归一化法计算各组成化合物的相对百分含量。所鉴定化合物的含量占全油的100%, 其主要成份1-辛烯-3-醇(蘑菇醇) (49.50%)、(E)-3-己烯-1-醇(青叶醇) (13.39%)、芳樟醇(9.41%)、环己醇(3.37%)、3-辛醇(1.69%)、n-正戊酸-(Z)-3-己烯酯(1.42%)、1-己醇(1.38%)、糠醛(1.37%)和a-萜品烯醇(1.17%)等9种化合物占全油的81.53%。     

木蹄层孔菌子实体化学成分及对肿瘤细胞的抑制作用的研究

运用硅胶、sephadex LH-20等柱色谱,从木蹄层孔菌子实体的乙醇提取物分离得到12个化合物,通过单体的理化性质、NMR和MS技术鉴定单体的结构为3-十六碳酸酯-7,22-二烯麦角甾醇（1）,十八烷酸（2）,棕榈酸（3）,7,22-二烯麦角甾-3-酮（4）,麦角甾-7,22-二烯-3-醇（5）,5,8-过氧麦角甾-6,22-二烯-3-醇（6）,3,3-二甲氧基-7,22-二烯麦角烷（7）,28-乙酰白桦脂醇（8）,白桦脂醇（9）,β-羟基十八烷酸（10）,9,10-二羟基十八烷酸（11）,瑞香素（12）。采用Alamar Blue法检测单体化合物对人肺癌细胞NCI-H 460和人胃癌细胞SGC-7901的抑制活性。结果表明,化合物4对NCI-H 460细胞株的抑制活性最高,化合物9对SGC-7901的抑制活性最高。     

褐薄小齿菌的化学成分研究

从褐薄小齿菌(Hydnellum concrescens)子实体中分离得到9个已知化合物,借助光谱手段,它们的化学结构分别鉴定为:friedelin(1),(22E,24R)-麦角甾-5,7,22-三烯-3β-醇(2),5α,8α-过氧-(22E,24R)-麦角甾-6,22-二烯-3β-醇(3),(22E,24R)-麦角甾-5,22-二烯-3β-羟基-7-酮(4),6-甲氧基-cerevisterol(5),thelephantin K(6),thelephantin I(7),thelephantin J(8),thelephantin L(9)。     

Exploiting volatile organic compounds in crop protection: A systematic review of 1-octen-3-ol and 3-octanone

The 21st century has brought new challenges to the agri-food industry due to population growth, global warming, and greater public awareness of environmental issues. Ensuring global food security for future generations is crucial. However, pests, weeds, and diseases still significantly contribute to crop losses, and the availability of effective conventional synthetic pesticides is decreasing. To address this, new and diverse pest management tools are needed. One pest management tool showing potential for invertebrate pest management is the exploitation of volatile organic compounds (VOCs)—in particular, the compounds 1-octen-3-ol and 3-octanone. This review aims to explore the extent to which 1-octen-3-ol and 3-octanone show potential in the future management of invertebrate crop and animal pests. A significant increase in the rate of publication of literature on the use of 1-octen-3-ol and 3-octanone in crop protection since 2018 is identified by this review, therefore, showing the potential importance of these compounds for use in future pest management. This review also identifies key interactions between naturally occurring biosynthesised 1-octen-3-ol and 3-octanone, and a range of invertebrate targets. Many of these interactions with key crop pests are sourced from the taxonomic families Lamiaceae, Fabaceae, and Trichomaceae. However, analysis of the practical application of these sources in an integrated pest management programme identifies clear limitations with the use of naturally occurring biosynthesised 1-octen-3-ol and 3-octanone. Rather, future focus should be placed on the development and exploitation of synthesised nature identical 1-octen-3-ol and 3-octanone for use as a biopesticide product. Overall, 1-octen-3-ol and 3-octanone show potential for exploitation in future crop protection, being abundant in source and diversity of invertebrate interactions. However, their use as a naturally occurring biosynthesised chemical is likely not practical for direct implementation in crop protection. Rather, focus should be placed on the development and exploitation of synthesised nature identical variants of these compounds for use as a biopesticide.     

土壤真菌 Aspergillus fumigatus固体发酵产物的化学成分及抗氧化活性研究

为研究来源于哀牢山国家级自然保护区河谷的土壤真菌Aspergillus fumigatus固体发酵产物的化学成分及抗氧化活性研究,采用正相硅胶柱层析、反相硅胶柱层析和Sephadex LH-20分离纯化,借助核磁共振波谱等方法鉴定化合物结构,从中共得到13个化合物,分别鉴定为rubrofusarin B(1)、rubrofusarin A(2)、carbonarone A(3)、aspernigrin A(4)、flavasperone(5)、(22 E,24 R)-5α,8α-过氧麦角甾-6,22-二烯-3β-醇(6)、(22 E,24 R)-5α,8α-过氧麦角甾-6,9(11),22-三烯-3β-醇(7)、ourosperone A(8)、(22 E,24 R)-麦角甾-5,7,22-三烯-3β-醇(9)、stigmast-1,5-dien-3β-ol(10)、fonsecinones A(11)、asperpyrone C(12)、asperpyrones B(13)。其中,化合物1~5和7~13为从该菌种中首次分离。抗氧化活性结果显示,化合物8对DPPH(IC₅₀=3.453 mg/mL)、ABTS+(IC₅₀=0.155 mg/mL)、OH(IC₅₀=0.019 mg/mL)自由基都有一定的清除效果。