Host-marking pheromone and use of previously established oviposition sites by the mediterranean fruit fly (Diptera: Tephritidae)

Under controlled conditions, the Mediterranean fruit fly, Ceratitis capitata(Wiedemann) preferred to initiate oviposition into preexisting, naturally formed oviposition punctures in a host fruit, kumquat (Fortunella japonica),over establishing new sites on the fruit. This preference was expressed despite the presence of naturally deposited host-marking pheromone (HMP)shown previously to deter oviposition. An almost-identical preference for existing punctures was expressed when females were presented with fruit bearing artificially made punctures on which HMP had been naturally deposited. Using artificial punctures and HMP extracts, the occurrence of punctures was manipulated independently of the presence of HMP.Under field-cage conditions, we found that (1) punctures stimulated egg-laying on kumquats, regardless of HMP treatment; (2) HMP extract inhibited egg-laying, regardless of the occurrence of punctures; and (3) the extent to which HMP inhibited egg-laying was greater on fruit free of punctures than on fruit bearing them. The physiological, evolutionary, and pest management implications of these results are discussed.     

Racemization of the aqua-{N-salicylidene-(S)-alaninato}copper(II) by reaction with potassium cyanate

Copper(II) N-salicylidene-(S)-alaninate trihydrate reacting as the S-enantiomeric parent compound with KOCN in hot diluted methanol yielded by slow crystallisation from the cooled reaction mixture (in the course of 1 day) the racemic product K[Cu{sal-(RS)-ala}(NCO)]. The parameters of the axial type EPR spectrum in X-band region and the LF band position in the electronic spectrum are typical of an axially distorted square pyramidal coordination of the Cu(II) atom in this complex. The spectral properties of the complex cuprate prepared and its basal crystallographic data are consistent with those of the earlier studied¹⁵ K₂[Cu₂{sal-(RS)-ala}₂(μ-NCO)₂] synthetized by using [Cu{sal-(RS)-ala}(H₂O)].H₂O as the racemic parent complex in the reaction mixture with KOCN.     

Host marking pheromone of Rhagoletis cerasi: field deployment of synthetic pheromone as a novel cherry fruit fly management strategy

We tested the efficacy of synthetic host marking pheromone (HMP) of the European cherry fruit fly (R. cerasi) as a fruit-infestation-reducing-agent in an experimental cherry orchard. Two different pheromone deployment strategies were compared: covering entire tree canopies with synthetic HMP or treating only one half (top to bottom or lower half) of the tree canopy. Pheromone application caused a tenfold reduction in fruit infestation if the entire tree canopy was covered (0.226 vs 0.021 pupae/fruit in untreated and treated trees, respectively). Results show, nevertheless, that a significant reduction in fruit infestation can be achieved by treating only one half of tree canopies (top to bottom) (0.021 vs 0.048 pupae/fruit when comparing totally vs partially treated trees). We conclude that synthetic cherry fruit fly HMP has potential as a fruit fly management tool, especially in cases where organically grown fruit reaches high market values.     

Oviposition Marking Behavior of <Emphasis Type="Italic">Diachasma alloeum</Emphasis>, (Hymenoptera: Braconidae), Parasitizing <Emphasis Type="Italic">Rhagoletis pomonella</Emphasis>, (Diptera: Tephritidae)

Diachasma alloeum (Muesebeck) (Hymenoptera: Braconidae) is a solitary larval endoparasitoid attacking Rhagoletis (Diptera: Tephritidae) species. Rhagoletis pomonella (Walsh) mark the surface of fruit after oviposition with an oviposition marking pheromone (OMP) which deters conspecific female flies. Herein we demonstrate that female D. alloeum wasps reared from either apple or hawthorn race R. pomenella larvae also deposit an OMP that reduces oviposition by conspecific female wasps. Significantly fewer wasps accepted fruit that had received prior wasp oviposition and OMP or OMP alone without oviposition compared with control fruit for a minimum of 7 days on both fruit types. Rinsing fruit with a 50% ethanol solution appeared to remove the OMP rendering fruit more acceptable for oviposition than marked fruit that was not rinsed. Wasps of each host race were able to detect and avoid the OMP of the sister race and fruit substrate type did not affect wasp response to the pheromone. The possibility of an internal marker deposited during oviposition is also discussed.     

<Emphasis Type="Italic">S</Emphasis>-isorobinal as the female sex pheromone from an alarm pheromone emitting mite, <Emphasis Type="Italic">Rhizoglyphus setosus</Emphasis>

The female sex pheromone of Rhizoglyphus setosus Manson (Astigmata: Acaridae) was identified as S-isorobinal (4S-4-isopropenyl-3-oxo-1-cyclohexene-1-carboxyaldehyde), which stimulated males sexually and enhanced the frequency of the male’s tapping and mounting behavior. Although the female hexane extract indicated no sign of sex pheromone activity against tested males, possibly due to the presence of the alarm pheromone neryl formate, an SiO₂ column fraction containing isorobinal elicited sex pheromone activity at a dose of one female equivalent. The stereochemistry of natural isorobinal was identified as S by an HPLC using a chiral column. Both S- and R-isorobinals exhibited maximum activity at the same dose of 1 and 10 ng with a convex dose–response relationship. Amounts of S-isorobinal were determined to be 11.7 ± 1.0 ng per female and 6.4 ± 1.3 ng per male by GLC. This is the second example of two pheromones (the alarm pheromone neryl formate, and the sex pheromone S-isorobinal) demonstrated to be components of the same opisthonotal gland secretion.Chemical ecology of astigmatid mites. LXXVIII     

Synthesis of Both the Enantiomers of 3-Octanol,the Pheromone of Various Species of Ants

(2S,3R,1′S,2′S)-Serricorole (1) and (2S,3R,1′R)-serricorone (2), sex pheromone components of the cigarette beetle (Lasioderma serricorne F.), were synthesized, starting from the enantiomers of methyl 3-hydroxypentanoate. The stereochemistry of the naturally occurring 1 was determined to be 2S,3R,1′S,2′S, and that of 2 to be 2S,3R,1′RS by comparing between the CD spectra of the natural and synthetic samples.     

Kinetic resolution of ketoprofen ester catalyzed by lipase from a mutant of CBS 5791

A biotransformation process was developed for the production of (S)-ketoprofen by enantioseletive hydrolysis of racemic ketoprofen ester using the mutant Trichosporon laibacchii strain CBS 5791. A satisfactory result was obtained, in which the E was 82.5, with an ee of 0.94 and a conversion of 0.47 under the optimum hydrolysis conditions [E is enantiomeric ratio, E=ln[1–X(1+ee)]/ln[1–X(1–ee)]; ee is enantiomeric excess, ee=(C_S–C_R)/(C_S+C_R): temperature of hydrolysis was 23°C]. The medium used in biotransformation was a mixture of growth broth and biotransformation broth at a ratio of 1:9, the concentration of Tween 80 was 15 g/l, the time of hydrolysis, 72 h. These results are promising for further scale-up. Tween 80 significantly improved lipase enantioselectivity and activity at the optimum concentration.     

Optical Resolution by Preferential Crystallization of (RS)-2-Amino-3-(2-carboxyethylthio)propanoic Acid

Electrophilic additions of DL- and L-Cys to propenoic acid afforded (RS)- and (R)-2-amino-3-(2-carboxyethylthio)propanoic acids [(RS)- and (R)-ACE], respectively. (RS)-ACE was found to exist as a conglomerate based on its melting point, solubility, and infrared spectrum. (RS)-ACE was optically resolved by preferential crystallization to yield (R)- and (S)-ACE. The obtained (R)- and (S)-ACE were efficiently recrystallized from water, taking account of the solubility of (RS)-ACE, to give them in optically pure form.     

Biological activities of Zn(II)-S-methyl-cysteine complex as antiradical,inhibitor of acid phosphatase enzyme and in vivo antidepressant effects

The antidepressant effect of simple Zn(II) salts has been proved in several animal models of depression. In this study, a coordination metal complex of Zn(II) having a sulfur containing ligand is tested as antidepressant for the first time. Forced swimming test method on male Wistar rats shows a decrease in the immobility and an increase in the swimming behavior after treatment with [Zn(S-Met)₂] (S-Met=S-methyl-l-cysteine) being more effective and remarkable than ZnCl₂. The thiobarbituric acid and the pyranine consumption (hydroxyl and peroxyl radicals, respectively) methods were applied to evaluate the antioxidant activity of S-Met and [Zn(S-Met)₂] showing evidence of attenuation of hydroxyl but not peroxyl radicals activities. UV-vis studies on the inhibition of acid phosphatase enzyme (AcP) demonstrated that S-methyl-l-cysteine did not produce any effect but, in contrast, [Zn(S-Met)₂] complex behaved as a moderate inhibitor. Finally, bioavailability studies were performed by fluorescence spectroscopy denoting the ability of the albumin to transport the complex.     

Influence of Conspecific Presence, Experience, and Host Quality on Oviposition Behavior and Clutch Size Determination in Anastrepha ludens (Diptera: Tephritidae)

Females of some insect species adjust the number of ovipositions and clutch size adaptively depending on conspecific density and probably experience. In a series of three experiments, we examined the effect of the presence of conspecifics, host quality, and oviposition experience on oviposition behavior and clutch size determination by females of the polyphagous fruit fly Anastrepha ludens (Diptera: Tephritidae). In the first experiment, we determined that grouped (eight females per cage) A. ludens females tended to visit and oviposit in more hosts than did solitary females probably as a result of stimulation by the presence of conspecifics. We also determined that females with previous oviposition experience visited and oviposited in more hosts than inexperienced ones. Importantly, when females were grouped, we observed significantly more landings on unoccupied hosts (i.e., devoid of flies) than on occupied ones (i.e., with at least one fly on it). However, oviposition experience, and not female density, was the most important factor affecting clutch size. Naive females deposited larger egg clutches than experienced ones. In the second experiment, we found that oviposition experience and host quality (i.e., clean fruit or fruit covered with a host marking pheromone [HMP] extract), influenced clutch size and the decision of females to defend or not defend the host. Clutch size and number of fights were greater on clean than on HMP-marked hosts. In the third experiment, we observed that host quality (i.e., size) played a significant role with regard to the number of female fights, host marking behavior, and clutch size. Specifically, females fought and dragged their aculeus longer on small- and medium-sized hosts than on large ones. But this behavior varied according to whether females were kept alone or grouped. Clutch size was greatest in the largest hosts. Considering all the above, we believe that the observed increase in ovipositional activity by grouped A. ludens females can be attributed to competition through mutual interference and not social facilitation as has been reported in other tephritid species.     

A novel approach to the assessment of fruit damage caused by <Emphasis Type="Italic">Carposina sasakii</Emphasis> (Lepidoptera: Carposinidae) using pheromone trap catches in Korean orchards

This study reports a model that utilizes pheromone trap catches to assess the fruit damage caused by Carposina sasakii. The model consisted of four steps: (1) obtaining influx population density using pheromone traps, (2) estimating the actual female population within a defined area using an estimated conversion rate, (3) calculating the total number of eggs using the oviposition model of C. sasakii, and (4) estimating the proportion of fruits infested with eggs (potential damaged fruits) using the relationship between mean egg density per fruit and the proportion of fruits infested with eggs. The relationship between mean egg density ([`(x)] \bar{x} ) per fruit and variance (s ²) was well described by Taylor’s power law, and its parameters were successfully incorporated into the equation that estimates the relationship between mean egg density and the proportion of fruits infested with eggs. In peach orchards, the model accurately predicted the proportion of fruits infested with eggs at the beginning of C. sasakii emergence in early season, but overestimated it in the mid-season. The fitting ability of the model outputs largely increased when the factor of oviposition behavior of C. sasakii was incorporated into the simulation processes, applying the allocation module of total eggs between peaches and apples.     

Influence of avocado (Persea americana) Cx-cellulase on the structural features of avocado cellulose

Avocado (Persea americana Mill.) fruit produce copious quantities of the enzyme Cx-cellulase (EC 3.2.1.4) during ripening. The possibility that Cx-cellulase is able to disrupt cellulose microfibril oranization was investigated using molecular weight (M_r), x-ray diffraction, and ultrastructural analyses of cell walls from unripe avocado fruit incubated with the purified enzyme. Results indicate that Cx-cellulase causes a downshift in the M_r of unbranched cell-wall polymers in the M_r range of 10⁶–10⁷ Da. There is an increase in the proportion of crystalline cellulose, and cellulose fibrils appear to lose cohesiveness in response to enzyme activity. We propose that Cx-cellulase attacks avocado cellulose at accessible sites in the peripheral and integral noncrystalline regions of the microfibril, resulting in a loss of cohesiveness within the fibril structure and an alteration in the binding of associated cell-wall matrix polysaccharides. The initial loss of avocado mesocarp firmness during fruit ripening may be linked to the onset of Cx-cellulase activity.Abbreviations CMC carboxymethylcellulose - DMAC dimethylacetamide - DS developmental stage - M molecular weight - XG xyloglucan     

Resolution of RS-abscisic acid and the separation of abscisic acid metabolites from plant tissue by high-performance liquid chromatography

Attempts to resolve the enantiomers of racemic abscisic acid (ABA) by high-performance liquid chromatograpy on a chiral stationary-phase column were unsuccessful. However, reduction of RS-methyl ABA (RS-Me-ABA) with sodium borohydride generates a new chiral centre and one of the two isomeric products, the RS-Me-1′,4′-cis-diol of ABA, was separated into its enantiomers by high-performance liquid chromatography on an optically active Pirkle column.High-performance liquid chromatography on a μBondapak C₁₈ column separated the metabolites and conjugates of [2-¹⁴C]ABA fed to tomato shoots. The resolution method was used to measure the relative proportions of R and S enantiomers in the free acid liberated from conjugates of ABA.     

S-isorobinal as the female sex pheromone from an alarm pheromone emitting mite, Rhizoglyphus setosus

The female sex pheromone of Rhizoglyphus setosus Manson (Astigmata: Acaridae) was identified as S-isorobinal (4S-4-isopropenyl-3-oxo-1-cyclohexene-1-carboxyaldehyde), which stimulated males sexually and enhanced the frequency of the male’s tapping and mounting behavior. Although the female hexane extract indicated no sign of sex pheromone activity against tested males, possibly due to the presence of the alarm pheromone neryl formate, an SiO₂ column fraction containing isorobinal elicited sex pheromone activity at a dose of one female equivalent. The stereochemistry of natural isorobinal was identified as S by an HPLC using a chiral column. Both S- and R-isorobinals exhibited maximum activity at the same dose of 1 and 10 ng with a convex dose–response relationship. Amounts of S-isorobinal were determined to be 11.7 ± 1.0 ng per female and 6.4 ± 1.3 ng per male by GLC. This is the second example of two pheromones (the alarm pheromone neryl formate, and the sex pheromone S-isorobinal) demonstrated to be components of the same opisthonotal gland secretion.     

Constitutional isomers, stereoisomers and conformers of bis[di-tert-butyl(trimethylsilyl)cyclopentadienyl]disulfane

Reaction of tBu₂(Me₃Si)C₅H₂Li with S₂Cl₂ leads to [tBu₂(Me₃Si)C₅H₂]₂S₂. This compound exists as a pair of diastereomers (1,2) with sulfur in an allylic position of the cyclopentadiene system. Each diastereomer exists as a racemate of RS,SR and RR,SS enantiomers, respectively. 1 rapidly, 2 slowly convert below room temperature to a pair of diastereomers (3,4) with sulfur in vinylic position. Again, each diastereomer exists as a racemate of RS,SR and RR,SS enantiomers. 3 and 4 are the stable constitutional isomers at ambient temperatures and do not interconvert. The structures of 2, 3 and 4 have been determined by single crystal X-ray diffraction.     

Intra-allelic variation in introns of the <Emphasis Type="Italic">S</Emphasis><Subscript><Emphasis Type="BoldItalic">13</Emphasis></Subscript><Emphasis Type="Italic">-RNase</Emphasis> allele distinguishes sweet,wild and sour cherries

The cherry (Prunus avium), a self-incompatible diploid species, and the sour cherry (Prunus cerasus), a self-incompatible or self-compatible allotetraploid species derived from P. avium and Prunus fruticosa, share several S-RNase alleles, including S ₁₃ . An inactive form, S ₁₃ °, is found in some sour cherries. Two (AT) microsatellites are associated with allele S ₁₃ -RNase, one in the first intron and one in the second. Their length polymorphisms were studied in 14 sweet and 17 wild cherries (both P. avium) and in 42 sour cherries. Fluorescent primers amplifying each microsatellite were designed and amplification products sized on an automated sequencer. Variants ranged from 247 to 273 bp for the first intron microsatellite and from 308 to 322 bp for the second. There were 34 combinations and, surprisingly, the lengths of the two microsatellites were correlated. Generally, the sweet, wild and sour cherries had different combinations, and the four examples of S ₁₃ °-RNase were associated with three different combinations. Certain sequences associated with the microsatellites match footprints of transposons. The distribution of combinations indicated little overlap between the three populations analysed and provided useful insights into relationships of some of the accessions allowing some parentages to be checked. In the diploid sweet and wild cherries, S ₁₃ variants presumably resulted from slippage during replication, but in the tetraploid sour cherries, which can have more than one copy of S ₁₃ or S ₁₃ °, intra-allelic crossing over may have generated new variants. The possible involvement of transposable elements in the origin of these microsatellites is considered.     

Synthesis of Streptovitacin-C2 Isomers

(2R*,4S*,6S*,αS*)- and (2R,4R,6R,αS)-Streptovitacin-C₂ (STV-C₂) (1a and 1b) were synthesized by an aldol condensation of (2R*,4S*)- or (2R,4R)-2,4-dimethyl-2-trimethylsiloxy-1-cyclohexanone (15a or 15b) with 4-(2-oxoethyl)-2,6-piperidinedione (16), which was followed by desilylation of the products. The stereochemistry of the synthesized STV-C₂ isomers (1a and 1b) was elucidated by NMR. STV-C₂ isomers (1a and 1b) did not show strong antimicrobial activity against Saccharomyces cerevisiae and Pyricularia oryzae.     

New tailored substituted benzothiazole Schiff base Cu(II)/Zn(II) antitumor drug entities: effect of substituents on DNA binding profile,antimicrobial and cytotoxic activity

New tailored Cu(II) & Zn(II) metal-based antitumor drug entities were synthesized from substituted benzothiazole o?vanillin Schiff base ligands. The complexes were thoroughly characterized by elemental analysis, spectroscopic studies {IR, ¹H & ¹³C NMR, ESI?MS, EPR} and magnetic susceptibility measurements. The structure activity relationship (SAR) studies of benzothiazole Cu(II) & Zn(II) complexes having molecular formulas [C₃₀H₂₂CuN₅O₇S₂], [C₃₀H₂₀Cl₂CuN₅O₇S₂], [C₃₀H₂₀CuF₂N₅O₇S₂], [C₃₀H₂₂N₄O₄S₂Zn], [C₃₀H₂₀Cl₂N₄O₄S₂Zn], and [C₃₀H₂₀F₂N₅O₇S₂Zn], with CT?DNA were performed by employing absorption, emission titrations, and hydrodynamic measurements. The DNA binding affinity was quantified by K _b and K _sv values which gave higher binding propensity for chloro-substituted Cu(II) [C₃₀H₂₀Cl₂CuN₅O₇S₂] complex, suggestive of groove binding mode with subtle partial intercalation. Molecular properties and drug likeness profile were assessed for the ligands and all the Lipinski’s rules were found to be obeyed. The antimicrobial potential of ligands and their Cu(II) & Zn(II) complexes were screened against some notably important pathogens viz., E. coli, S. aureus, P. aeruginosa, B. subtilis, and C. albicans. The cytotoxicity of the complexes [C₃₀H₂₀Cl₂CuN₅O₇S₂], [C₃₀H₂₀CuF₂N₅O₇S₂], [C₃₀H₂₀Cl₂N₄O₄S₂Zn], and [C₃₀H₂₀F₂N₅O₇S₂Zn] were evaluated against five human cancer cell lines viz., MCF?7 (breast), MIA?PA?CA?2 (pancreatic), HeLa (cervix) and Hep?G2 (Hepatoma) and A498 (Kidney) by SRB assay which revealed that chloro-substituted [C₃₀H₂₀Cl₂CuN₅O₇S₂] complex, exhibited pronounced specific cytotoxicity with GI₅₀ value of 4.8 μg/ml against HeLa cell line. Molecular docking studies were also performed to explore the binding modes and orientation of the complexes in the DNA helix.     

Preparation of Four Geometric Isomers of (11E)-4,6,11-Hexadecatrienal and Their Effect toward Male Eri-Silk Moths

Four geometric isomers of (11E)-4,6,11-hexadecatrienal were prepared, and their pheromone activity towards male eri-silk moths was evaluated. The EAG activity of each isomer was determined by the EAG-GLC method in order of increasing activity to be (4Z,6E,11E)- and (4E,6E,11E)?? (4E,6Z,11E) ?? (4Z,6Z,11E)-hexadecatrienal.     

Cytotoxic and Genotoxic Effects of <Emphasis Type="Italic">cis</Emphasis>-Tetraammine(oxalato)Ruthenium(III) Dithionate on the Root Meristem Cells of <Emphasis Type="Italic">Allium cepa</Emphasis>

Ruthenium complexes have attracted much attention as possible building blocks for new transition-metal-based antitumor agents. The present study examines the mitotoxic and clastogenic effects induced in the root tips of Allium cepa by cis-tetraammine(oxalato)ruthenium(III) dithionate {cis-[Ru(C₂O₂)(NH₃)₄]₂(S₂O₆)} at different exposure durations and concentrations. Correlation tests were performed to determine the effects of the time of exposure and concentration of ruthenium complex on mitotic index (MI) and mitotic aberration index. A comparison of MI results of cis-[Ru(C₂O₂)(NH₃)₄]₂(S₂O₆) to those of lead nitrate reveals that the ruthenium complex demonstrates an average mitotic inhibition eightfold higher than lead, with the frequency of cellular abnormalities almost fourfold lower and mitotic aberration threefold lower. A. cepa root cells exposed to a range of ruthenium complex concentrations did not display significant clastogenic effects. Cis-tetraammine(oxalato)ruthenium(III) dithionate therefore exhibits a remarkable capacity to inhibit mitosis, perhaps by inhibiting DNA synthesis or blocking the cell cycle in the G2 phase. Further investigation of the mechanisms of action of this ruthenium complex will be important to define its clinical potential and to contribute to a novel and rational approach to developing a new metal-based drug with antitumor properties complementary to those exhibited by the drugs already in clinical use.