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B E Mazomenos - One of the best experts on this subject based on the ideXlab platform.
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almond seed wasp hymenoptera eurytomidae sex pheromone effect of trap type trap position blend ratio and time of the day on male attraction
Bulletin of Entomological Research, 2008Co-Authors: Christos G Athanassiou, Nickolas G Kavallieratos, B E MazomenosAbstract:Field trials were carried out in order to evaluate some of the factors affecting male response of the almond seed wasp, Eurytoma amygdali Enderlein, to traps baited with the Alkadienes (Z,Z)-6,9-tricosadiene and (Z,Z)-6,9-pentacosadiene, the male attractant of this species. The trials were conducted in Latomia, Microthivae, Kanalia and Sykourion (Thessaly, Central Greece) during the 2004 growing season. In all regions, captures in traps baited with a 7:3 ratio of the above blend significantly and positively correlated with male emergence from infested almonds that had been placed in cages in the experimental fields. Traps baited with the 7:3 pheromone ratio were significantly more effective in capturing males than traps baited with the 1:1 ratio, supporting the hypothesis that (Z,Z)-6,9-tricosadiene is the main component of this attractant. Of four trap types tested, Rebel and Lasiotraps attracted significantly more males than Delta and Funnel traps. Height had no effect on trap efficiency; however, males were captured earlier in the day in traps placed 2.3 m above grown than in traps placed 1.3 m above grown. Most male activity was recorded between 10 and 12 h, but captures were continuously recorded during the entire monitoring interval from 6 to 17 h.
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Alkadienes and alkenes sex pheromone components of the almond seed wasp eurytoma amygdali
Journal of Chemical Ecology, 2001Co-Authors: F D Krokos, M A Konstantopoulou, B E MazomenosAbstract:Whole body extracts of virgin Eurytoma amygdali females were attractive to males in laboratory bioassays. Extracts of various body parts of the female wasp elicited different responses to males, with the thorax extract being the most active. Preparative fractionation of the crude hydrocarbon extract on a silver nitrate impregnated silica gel column (alkanes, alkenes, and Alkadienes) revealed that the highest male response was elicited by Alkadienes and the lowest by alkenes, with the alkane fraction being inactive. The identification of alkenes and Alkadienes was based on gas chromatographic, mass spectrometric, and gas-phase infrared data. Laboratory bioassays suggested that the two Alkadienes, (Z,Z)-6,9-tricosadiene [(Z,Z)-6,9-C23:2], and (Z,Z)-6,9-pentacosadiene [(Z,Z)-6,9-C25:2], and to a lesser extent alkenes, identified in the female extract of E. amygdali were male attractants.
Julian P Sachs - One of the best experts on this subject based on the ideXlab platform.
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co occurrence of long chain diols keto ols hydroxy acids and keto acids in recent sediments of lake el junco galapagos islands
Organic Geochemistry, 2011Co-Authors: Zhaohui Zhang, Pierre Metzger, Julian P SachsAbstract:Lipid biomarkers in lacustrine sediments provide valuable information about lake history and environmental change. Here we report the occurrence of a unique set of lipid biomarkers from a freshwater crater lake, El Junco, in the Galapagos. In addition to previously reported Alkadienes, botryococcenes and lycopadienes indicative of Botryococcus braunii A, B and L races, we find highly branched C25 isoprenoids (HBIs) from diatoms, monomethyl alkanes likely from insect epicuticular waxes, long chain alkenols, diols and a triol, keto-ols, hydroxy acids and keto acids. Saturated and mono-unsaturated long chain diols from C30–C36 had terminal hydroxyl groups and hydroxyl groups between the ω16 and ω20 positions. Vicinal diols with hydroxyl groups at ω9 and ω10 were likely from the floating fern Azolla. C30–C36 keto-ols, mid-chain hydroxy and keto acids had mid-chain functional groups at similar positions to the diols, suggesting common origins. The predominance of ω20-hydroxy acids and diols, together with 20,21-dihydroxy-nonacosanoic acid is indicative of an Azolla source, while ω16 and ω18 hydroxy acids and diols imply a microalgal source.
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biomarker evidence for the co occurrence of three races a b and l of botryococcus braunii in el junco lake galapagos
Organic Geochemistry, 2007Co-Authors: Zhaohui Zhang, Pierre Metzger, Julian P SachsAbstract:In spite of the fact that individual races of Botryococcus braunii are widely distributed in lakes, reports of the co-exis- tence of different chemical races are rare. Here we report biomarker evidence for the co-occurrence of three different races of B. braunii (A, B and L) in the water column and sediments of El Junco Lake, a freshwater crater lake at 700 m elevation on San Cristobal Island, Galapagos. We also show the existence of lycopadienes and lycopatrienes in suspended particles and sediments. Biomarker indicators of the three races were: cis and trans C25-C31 n-Alkadienes and a C29 triene for race A, a series of C34H58 botryococcenes for race B, and a C40H78 hydrocarbon, trans,trans-lycopadiene accompanied by minor amounts of isomers for race L. Epoxides derived from n-Alkadienes and trans,trans-lycopadiene, specific to races A and L respectively, were also detected. Several previously unreported lycopadienes and lycopatrienes were identified in both the water column and sediment, and are believed to represent by-products and intermediates, respectively, of trans,trans-lycopadiene synthesis. Botryococcene and lycopadiene concentrations reached 16.7 and 0.8 mg/g dry sediment in near-surface sediments, and varied over more than three orders of magnitude, while n-Alkadienes were present in trace quantities. Pyrolysates from the kerogen fraction of sediment contained lycopadiene and Alkadiene related lipids along with chemically resistant polymers of B. braunii cell walls. Apparently n-Alkadienes, botryococcenes and lycopadienes and -trienes can survive in oxic sedi- ments for several decades, and the down core variation in these lipids likely reflects changes in lake hydrology, alternately favoring the bloom or near-extinction of B. braunii race B. � 2007 Elsevier Ltd. All rights reserved.
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hydrogen isotope fractionation in freshwater algae i variations among lipids and species
Organic Geochemistry, 2007Co-Authors: Zhaohui Zhang, Julian P SachsAbstract:Five species of freshwater green algae, including three strains of Botryococcus braunii (two A Race, one B Race), Eudorina unicocca and Volvox aureus, were cultured under controlled conditions in media containing different concentrations of deuterium. The hydrogen isotopic ratios of lipids in the algae, including Alkadienes, botryococcenes, heptadecenes, fatty acids, and phytadiene, were measured by gas chromatography–isotope ratio-mass spectrometry (GC–IRMS) and found to closely track water δD values. While correlation coefficients (R2) in excess of 0.99 for all lipids in all species suggest that lipid δD values can be used to determine water δD values, hydrogen isotope fractionation was found to vary systematically between lipids and lipid homologues within a single alga, as well as for the same lipid between species of algae. Under similar growth conditions, two species of Chlorophyceae (Eudorina unicocca and Volvox aureus) and three species of Trebouxiophyceae (Botryococcus braunii) produced palmitic acid (C16 fatty acid) that differed by 90–100‰ relative to water. Ubiquitous lipids such as palmitic acid, with a multitude of aquatic and terrestrial sources, are therefore not good targets for D/H-based paleohydrologic reconstructions. In addition to the use of source-specific biomarkers that derive unambiguously from a single family or species, paleohydrologic applications of lipid D/H ratios will need to consider the as yet unstudied potential influence that environmental parameters such as nutrients, light and temperature, etc., may have on D/H fractionation during lipid synthesis.
Shigeru Okada - One of the best experts on this subject based on the ideXlab platform.
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Hydrocarbon productivities in different Botryococcus strains: comparative methods in product quantification.
Journal of Applied Phycology, 2010Co-Authors: Ela Eroglu, Shigeru Okada, Anastasios MelisAbstract:Six different strains of the green microalgae Botryococcus belonging to the A-race or B-race, accumulating Alkadiene or botryococcene hydrocarbons, respectively, were compared for biomass and hydrocarbon productivities. Biomass productivity was assessed gravimetrically upon strain growth in the laboratory under defined conditions. Hydrocarbon productivities were measured by three different and independent experimental approaches, including density equilibrium of the intact cells and micro-colonies, spectrophotometric analysis of hydrocarbon extracts, and gravimetric quantitation of eluted hydrocarbons. All three hydrocarbon-quantitation methods yielded similar results for each of the strains examined. The B-race microalgae Botryococcus braunii var. Showa and Kawaguchi-1 constitutively accumulated botryococcene hydrocarbons equivalent to 30% and 20%, respectively, of their overall biomass. The A-race microalgae Botryococcus braunii, varieties Yamanaka, UTEX 2441 and UTEX LB572 constitutively accumulated Alkadiene hydrocarbons ranging from 14% to 13% and 10% of their overall biomass, respectively. Botryococcus sudeticus (UTEX 2629), a morphologically different green microalga, had the lowest hydrocarbon accumulation, equal to about 3% of its overall biomass. Results validate the density equilibrium and spectrophotometric analysis methods in the quantitation of botryococcene-type hydrocarbons. These analytical advances will serve in the screening and selection of B. braunii and of other microalgae in efforts to identify those having a high hydrocarbon content for use in commercial applications.
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phylogenetic placement genome size and gc content of the liquid hydrocarbon producing green microalga botryococcus braunii strain berkeley showa chlorophyta
Journal of Phycology, 2010Co-Authors: Taylor L Weiss, Shigeru Okada, Spencer J Johnston, Kazuhiro Fujisawa, Koremitsu Sumimoto, Joseph Chappell, Timothy P DevarenneAbstract:We report the genome size and the GC content,and perform a phylogenetic analysis on Botryococcusbraunii Ku¨tz., a green, colony-forming, hydrocarbon-rich alga that is an attractive source for biopetro-leum. While the chemistry of the hydrocarbonsproduced by the B race of B. braunii has beenstudied for many years, there is a deficiency of infor-mation concerning the molecular biology of thisalga. In addition, there has been some discrepancyas to the phylogenetic placement of the Berkeley (orShowa) strain of the B race. To clarify its classifica-tion, we isolated the Berkeley strain nuclear SSU(18S) rRNA gene and b-actin cDNA and used thesesequences for phylogenetic analysis to determinethat the Berkeley strain belongs to the Trebouxio-phyceae class. This finding is in agreement withother B races of B. braunii, indicating the Berkeleystrain is a true B race of B. braunii. To better under-stand molecular aspects of B. braunii, we obtainedthe Berkeley strain genome size as a first step ingenome sequencing. Using flow cytometry, we deter-mined the B. braunii Berkeley genome size to be166.2 ± 2.2 Mb. We also estimated the GC contentof the Berkeley strain as 54.4 ± 1.2% for expressedgene sequences.Key index words:18S rRNA sequences;Botryococcusbraunii;Chlorophyta;GCcontent;genomesize;hydrocarbons; phylogenetic analysis; Trebouxio-phyceaeAbbreviations: 18S rRNA, nuclear SSU(18S)ribosomalRNA; cDNA, complementary DNA; RT–PCR,reverse transcription–PCRB. braunii is a green, colonial microalga withunique liquid-hydrocarbon biosynthetic capabilitiesthat have made this organism a promising source ofrenewable hydrocarbon fuels. The cells of a B. brau-nii colony are held together by an extracellularmatrix composed of a polymer core of aldehydesderived from very long-chain fatty acids (Maxwellet al. 1968, Knights et al. 1970). Although some B.braunii liquid hydrocarbons can be found intracellu-larly, most liquid hydrocarbons are retained withinthe colony extracellular matrix.Three distinct races of B. braunii (A, B, and L)are classified by the type of hydrocarbons occurringin the extracellular matrix. The A race accumulatesthe fatty acid–derived Alkadienes and alkatrienes,while the L race accumulates the tetraterpene lyco-padiene. The focus of this study, the B race, accu-mulates the triterpenoid hydrocarbons known asbotryococcenes (Banerjee et al. 2002, Metzger andLargeau 2005).B. braunii possesses many characteristics thatmake it attractive as a biofuel feedstock source.B. braunii has been observed forming massive, densefreshwater blooms, and it is suggested that B. brau-nii oils have contributed to oil deposits throughoutthe world (Traverse 1955, Gelpi et al. 1968, Wake
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Hydrocarbon productivities in different Botryococcus strains: comparative methods in product quantification
2010Co-Authors: Ela Eroglu, Shigeru Okada, Anastasios MelisAbstract:Abstract Six different strains of the green microalgae Botryococcus belonging to the A-race or B-race, accumulating Alkadiene or botryococcene hydrocarbons, respectively, were compared for biomass and hydrocarbon productivities. Biomass productivity was assessed gravimetrically upon strain growth in the laboratory under defined conditions. Hydrocarbon productivities were measured by three different and independent experimental approaches, including density equilibrium of the intact cells and micro-colonies, spectrophotometric analysis of hydrocarbon extracts, and gravimetric quantitation of eluted hydrocarbons. All three hydrocarbon-quantitation methods yielded similar results for each of the strains examined. The B-race microalgae Botryococcus braunii var. Showa and Kawaguchi-1 constitutively accumulated botryococcene hydrocarbons equivalent to 30 % and 20%, respectively, of their overall biomass. The A-race microalgae Botryococcus braunii, varieties Yamanaka, UTEX 2441 and UTEX LB572 constitutively accumulated Alkadiene hydrocarbons ranging from 14 % to 13 % and 10 % of their overall biomass, respectively. Botryococcus sudeticus (UTEX 2629), a morphologically different green microalga, had the lowest hydrocarbon accumulation, equal to about 3 % of its overall biomass. Results validate the density equilibrium and spectrophotometric analysis methods in the quantitatio
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hydrocarbon composition of newly isolated strains of the green microalga botryococcus braunii
Journal of Applied Phycology, 1995Co-Authors: Shigeru Okada, Masahiro Murakami, Katsumi YamaguchiAbstract:Four new strains of Botryococcus braunii were isolated from Japanese waters and cultured under defined conditions. Their hydrocarbon content and composition were analyzed and compared with those of the Darwin and Berkeley strains. The Yamanaka strain produced only Alkadienes characteristic of the A race, whereas the others, the Yayoi, Kawaguchi-1 and -2 strains as well as the Darwin and Berkeley strains, produced botryococcenes peculiar to the B race. The hydrocarbon content of the Yamanaka strain was 16.1 % dry weight and that of the B race strains ranged from 9.7 to 37.9%. Botryococcene composition of the Japanese strains differed from each other as well as from the Darwin and Berkeley strains. More than 50% of the hydrocarbons in the Yayoi, Darwin, and Berkeley strains were composed of C34H58, but the main components were different from one another as isomers. The Kawaguchi-1 and -2 strains did not have a high level of C34 botryococcenes, C32 ones being the main components. In these strains significant amounts of squalene-related compounds were detected.
Mirela Dumitrescu - One of the best experts on this subject based on the ideXlab platform.
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recognition of alkenones in a lower aptian porcellanite from the west central pacific
Organic Geochemistry, 2004Co-Authors: Simon C. Brassell, Mirela DumitrescuAbstract:ODP Leg 198 drilling on Shatsky Rise recovered a lower Aptian porcellanite ( � 120.5 Ma) deposited during oceanic anoxic event (OAE) 1a that contains C36–C39 alkadienones: C37:2 and C39:2 alkadien-2-ones and C36:2 and C38:2 alkadien-3-ones. This alkenone distribution differs from that typical of contemporary sediments and haptophyte algae, but resembles that of Cretaceous sediments from the Blake-Bahama basin. The discovery of alkenones in the early Aptian extends their sedimentary record by 15 M.y. to 120.5 M.y. and demonstrates the potential for long-term survival of these diagnostic functional lipids under favorable depositional conditions and subsequent shallow burial. It also contributes to the understanding and reconstruction of evolutionary developments in alkenone distributions and biosynthesis over geologic time. # 2003 Elsevier Ltd. All rights reserved.
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recognition of alkenones in a lower aptian porcellanite from the west central pacific
Organic Geochemistry, 2004Co-Authors: Simon C. Brassell, Mirela DumitrescuAbstract:Abstract ODP Leg 198 drilling on Shatsky Rise recovered a lower Aptian porcellanite (∼120.5 Ma) deposited during oceanic anoxic event (OAE) 1a that contains C36–C39 alkadienones: C37:2 and C39:2 alkadien-2-ones and C36:2 and C38:2 alkadien-3-ones. This alkenone distribution differs from that typical of contemporary sediments and haptophyte algae, but resembles that of Cretaceous sediments from the Blake-Bahama basin. The discovery of alkenones in the early Aptian extends their sedimentary record by 15 M.y. to 120.5 M.y. and demonstrates the potential for long-term survival of these diagnostic functional lipids under favorable depositional conditions and subsequent shallow burial. It also contributes to the understanding and reconstruction of evolutionary developments in alkenone distributions and biosynthesis over geologic time.
Christos G Athanassiou - One of the best experts on this subject based on the ideXlab platform.
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almond seed wasp hymenoptera eurytomidae sex pheromone effect of trap type trap position blend ratio and time of the day on male attraction
Bulletin of Entomological Research, 2008Co-Authors: Christos G Athanassiou, Nickolas G Kavallieratos, B E MazomenosAbstract:Field trials were carried out in order to evaluate some of the factors affecting male response of the almond seed wasp, Eurytoma amygdali Enderlein, to traps baited with the Alkadienes (Z,Z)-6,9-tricosadiene and (Z,Z)-6,9-pentacosadiene, the male attractant of this species. The trials were conducted in Latomia, Microthivae, Kanalia and Sykourion (Thessaly, Central Greece) during the 2004 growing season. In all regions, captures in traps baited with a 7:3 ratio of the above blend significantly and positively correlated with male emergence from infested almonds that had been placed in cages in the experimental fields. Traps baited with the 7:3 pheromone ratio were significantly more effective in capturing males than traps baited with the 1:1 ratio, supporting the hypothesis that (Z,Z)-6,9-tricosadiene is the main component of this attractant. Of four trap types tested, Rebel and Lasiotraps attracted significantly more males than Delta and Funnel traps. Height had no effect on trap efficiency; however, males were captured earlier in the day in traps placed 2.3 m above grown than in traps placed 1.3 m above grown. Most male activity was recorded between 10 and 12 h, but captures were continuously recorded during the entire monitoring interval from 6 to 17 h.
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evaluation of the major female eurytoma amygdali sex pheromone components z z 6 9 tricosadiene and z z 6 9 pentacosadiene for male attraction in field tests
Journal of Chemical Ecology, 2004Co-Authors: Basilis E Mazomenos, Christos G Athanassiou, Nickolas G Kavallieratos, Panagiotis MilonasAbstract:We evaluated the attraction of male almond seed wasp Eurytoma amygdali to the synthetic Alkadienes (Z,Z)-6,9-tricosadiene and (Z,Z)-6,9-pentacosadiene and their blend in almond orchards using baited rubber septa attached to cardboard rectangular adhesive traps. The two Alkadienes were recently isolated from virgin female whole body extracts and SPME collected volatiles. The alkenes (Z)-9-tricosene, (Z)-9-pentacosene, and (Z)-9-heptacosene, present in female extracts, were also added to the blend of the Alkadienes and tested. The Alkadienes tested individually attracted males when the traps were baited with doses ranging from 10 to 30 mg/trap. The maximum number of males was attracted to traps baited with 10 mg of a (Z,Z)-6,9-C23:2:(Z,Z)-6,9-C25:2 blend at a ratio of 7:3. Results with the three alkenes added to the blend were inconclusive because of low populations. The present study on E. amygdali is the first one reporting attraction of males to synthetic sex pheromone components in field trials for a Eurytomidae species. The synthetic Alkadienes blend offers the potential to develop an effective system for monitoring populations of the almond seed wasp in almond orchards.