Biochemical Entomology

Lactic acid the most widely occurring hydroxy-carboxylic acid has traditionally been used as food preservative and acidulent. So long, it has been produced through either chemical synthesis route or fermentation route the latter being the dominating one. Despite its tremendous potential for large scale production and use in a wide variety of applications, cost-effective production of high purity lactic acid has remained a challenge for decades, mainly due to high downstream processing cost. In the recent years, possibility of integration of highly selective membranes with the conventional fermentors has opened a golden opportunity for full commercial exploitation of the tremendous application potential of this wonder chemical. This paper discusses recent developments of such membrane-based processes representing process intensification in production of monomer grade lactic acid while suggesting a very promising production scheme.

Amritodus atkinsoni and Idioscopus clypeus are the two species belong to subfamily Idiocerinae BAKER, 1915 (Hemiptera: Cicadellidae). These are the most destructive pests of Mango fruit orchards in District Faisalabad. The research work for purpose of species identification was conducted In Taxonomic lab, Department of Entomology, University of Agriculture, Faisalabad during year 2018-2019. The Mango Leafhopper specimens were collected with the help of sweep netting from mango orchards. The specimens after collection were killed by placing them in poison bottle. Stereo light microscope digital camera fitted B41 Olympus was used with magnification power Omax 3.5X-90X USB3 18 MP and variable magnification to identify key characters of leafhoppers from District Faisalabad. Taxonomic keys and checklist of subfamily Idiocerinae were provided for further description.

Cotton production is one of the main sources of income for the population and contributes to the socioeconomic development in the northern and central areas of Côte d'Ivoire. However, cotton crop is subject to large and diversified pest problems, including jassids. Heavy infestations of jassids are likely to induce the stopping of plant development or the shedding of reproductive organs. For the last decade, there has been an increase and persistence of leafhopper attacks throughout the crop cycle despite insecticide treatments. This study aims to determine the biochemical mechanism likely to be involved in insecticide susceptibility of jassids. A biochemical assay of enzyme activities was performed on adult populations of jassids collected from cotton fields in six different localities (Bouaké, Korhogo, Boundiali, Ferké, Ouangolo and Niakara) within the cotton growing area of Côte d'Ivoire. The method of Brogdon et al. (1997) was adopted with minor modifications. Alpha-esterase activity values ranged from 380.334 to 965.775 nmol α-naphtol/min/mg protein for Bouaké and Ouangolo respectively. Beta-esterase activity ranged from 398.640 nmol β-naphtol/min/mg protein for Bouaké to 1,528.885 nmol β-naphtol/min/mg protein for Ouangolo. Oxidase activity ranged from 0.016 nmol P450 EU/mg protein for Ferké to 0.038 nmol P450 EU/mg protein for Ouangolo. Glutathione-δ-transferases varied between 0.554 nmol GSH conj/min/mg protein for Ferké and 1.128 nmol GSH conj/min/mg protein for Niakara.

We evaluated the utility of DNA barcodes for identifying Thaumatotibia
leucotreta (Meyrick) infesting sweet oranges in Nigeria. Approximately 658 bp of the mitochondrial gene cytochrome oxidase subunit I (COI) was amplified, sequenced, and analyzed for 32 adult samples, eight from each of the four geopolitical zones of Nigeria. All of the samples had identical sequences except for two, both of which showed a transition from “G” to “A” at position 433 bp. DNA barcodes of specimens from Nigeria showed 100% similarity with sequences of T. leucotreta in
the Barcode of Life Database (BOLD) from Kenya and South Africa; all the Nigerian samples cluster with T. leucotreta from BOLD with a bootstrap support of 90. DNA barcoding is consistent with identifications of the samples based on morphology.

Raspy crickets (Orthoptera: Gryllacrididae) are unique among the orthopterans in producing silk, which is used to build shelters. This work studied the material composition and the fabrication of cricket silk for the first time. We examined silk-webs produced in captivity, which comprised cylindrical fibers and flat films. Spectra obtained from micro-Raman experiments indicated that the silk is composed of protein, primarily in a beta-sheet conformation, and that fibers and films are almost identical in terms of amino acid composition and secondary structure. The primary sequences of four silk proteins were identified through a mass spectrometry/cDNA library approach. The most abundant silk protein was large in size (300 and 220 kDa variants), rich in alanine, glycine and serine, and contained repetitive sequence motifs; these are features which are shared with several known beta-sheet forming silk proteins. Convergent evolution at the molecular level contrasts with development by crickets of a novel mechanism for silk fabrication. After secretion of cricket silk proteins by the labial glands they are fabricated into mature silk by the labium-hypopharynx, which is modified to allow the controlled formation of either fibers or films. Protein folding into beta-sheet structure during silk fabrication is not driven by shear forces, as is reported for other silks.

Whereas there is growing interest in producing biomaterials containing coiled-coils, relatively few studies have made use of
naturally occurring fibrous proteins. In this study, we have characterized fibrous proteins used by mother praying mantises to produce an extensive covering for their eggs called an ootheca and demonstrate the production of artificial ootheca using recombinantly produced proteins. Examination of natural oothecae by infrared spectroscopy and solid-state nuclear
magnetic resonance revealed the material to consist of proteins organized predominately as coiled-coils. Two structural proteins, Mantis Fibroin 1 and Mantis Fibroin 2, were identified in ootheca from each of three species. Between species, the primary sequences of both proteins had diverged considerably, but other features were tightly conserved, including low molecular weight, high abundance of Ala, Glu, Lys, and Ser, and a triblock-like architecture with extensive central coiled-coil domain. Mantis fibroin hydrophobic cores had an unusual composition containing high levels of alanine and aromatic residues. Recombinantly produced mantis fibroins folded into coiled-coils in solution and could be fabricated into solid materials with high coiled-coil content. The structural features of mantis fibroins and their straightforward recombinant production make them promising templates for the production of coiled-coil biomimetics materials.

Extensive folklore records from pre-modern Estonia give us an excellent opportunity to study a variety of local plant knowledge and plant use among the peasantry in various parts of the country. One important biocultural domain where plant knowledge has been crucial was in the various methods of combating different ectoparasites that cohabited and coexisted with humans and their domestic animals. Some of these methods were widely known (world-wide, Eurasia, Europe, Baltic Rim), while others were more local. Here we discuss ways of reducing clothes moths Tineola bisselliella (Hummel) (Lepidoptera: Tineidae), human fleas Pulex irritons L. (Siphonaptera: Pulicidae) and bedbugs Cimex lectularius L. (Hemiptera: Cimicidae) with the help of plants. Various taxa used as traditional repellents have been identified. The use of plants as repellents and their toxic principles are also discussed from a comparative perspective.

Resumo. Cynaeus angustus (LeConte) caracteriza-se como praga de grãos armazenados, possui diversos substratos alimentares listados em sua ecologia alimentar entre eles o milho, trigo, sorgo e soja. Porém não há registro de seus hábitos no amendoim in natura, assim o objetivo deste estudo foi apresentar a tabela de vida estática, para C. Angustus em condições de laboratório utilizando como substrato o amendoim, e avaliar a composição proteica nos diferentes estádios de desenvolvimento de C. angustus. A quantificação de proteínas foi feita pelo método de microbiureto e o método qualitativo foi feito per método eletroforético. Assim a quantificação de proteínas indicou um aumento de seus valores durante o desenvolvimento dos insetos: larvas 38,22 mg/mL, pupas 47,53 mg/mL e adultos de 60.00 mg/mL. Foi possível observar o perfil electroforético de C. angustus indicando um aumento significativo na variedade de proteínas (29 a 700 kDa) sobre as diferentes etapas deste inseto. Os dados obtidos pela analise populacional indicam que C. angustus apresenta maiores taxas iniciais de sobrevivência, alto potencial biótico e desenvolvimento contínuo em condições favoráveis que mostram potenciais condições de cultivo e pode ser usado como uma fonte nutricional tal como mencionado para outras espécies da mesma família. Abstract. Cynaeus angustus (LeConte) is characterized as a pest of stored grain, there is several food substrates on their feeding ecology including corn, wheat, sorghum and soybeans. But there is no record of their habits in peanut in natura, so the aim of this study was to present the static life table, to C. angustus in laboratory conditions using as substrate the peanut, and evaluate the protein composition in different stages of development C. angustus. The quantification of proteins was taken by microbiureto method and qualitative method was done per electrophoretic method. Protein quantitation indicated an increase of its values during development of insects: larvae 38,22 mg/mL, pupae 47,53 mg/mL and adults 60,00 mg/mL. It was possible to observe the electrophoretic profile C. angustus showed a significant increase in the variety of proteins (29-700 kDa) on the different stages of the insect. Data obtained from the population analysis indicate that C. angustus shows higher initial survival rates, high biotic potential and continuous developing in favorable conditions showing potential growing conditions and, that can be used as a nutritional source such as mentioned for other species of the same family.