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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Contribuições à propagação de araçazeiro (Psidium cattleianum Sab.) e grumixameira (Eugenia brasiliensis Lam.) / Contributions to the propagation of strawberry guava (Psidium cattleianum Sab.) and grumixameira (Eugenia brasiliensis Lam.)

Rodriguez, Edwin Antonio Gutierrez January 2013 (has links)
Myrtaceae possui mais de 3000 espécies sendo Acca sp, Eucalyptus sp, Myrcianthes sp, Myrcia sp, Psidium sp, os gêneros mais representativos pela importância ambiental, econômica, farmacêutica, entre outras. O presente estudo teve como objetivo contribuir no aprimoramento das técnicas de propagação de Psidium cattleianum Sab e Eugenia brasiliensis Lam por estaquia e semeadura em condições in vivo e in vitro. Para P. cattleianum, na propagação in vivo foram testados: Doses de AIB na presença ou ausência de BAP no enraizamento de estacas herbáceas, e indução ao enraizamento de estacas de folha; na propagação in vitro foi testado, para organogênese: Efeito do acido giberélico, do tempo de imersão em NaOCl (2 %) e água 55°C por 10 min na germinação das sementes; Efeito da composição do meio de cultura e da relação entre concentrações de BAP:ANA no desenvolvimento de miniestacas. Para calogênese, para desinfestação de explantes na fase de introdução, foram testados: Pré-tratamento com solução de tiofanato-metílico (49 mg L-1 i.a) misturado com ampicilina (250 mg L-1); efeito do tempo de imersão e do pH da solução de NaOCl. Para desdiferenciação foi testado: Doses de cinetina na indução de calogênese em lâmina foliar e doses de 2,4-D em porções de hipocótilo. Para E. brasiliensis , in vivo, foram testados o efeito da concentração de AIB na indução de enraizamento de estacas e in vitro foi testado o efeito da concentração de AG3 no estabelecimento de miniestacas. Os principais resultados permitem inferir que as duas espécies são passíveis de se propagar por estaquia, sendo que para E. brasiliensis a técnica deve ser aprimorada para aumentar o percentual de enraizamento. Na propagação in vitro de P. cattleianum o meio WPM foi mais adequado para o estabelecimento de miniestacas. A eficiência do NaOCl na desinfestação de sementes e explantes para calogênese é afetada pela concentração da solução, tempo de contato e pH da solução. A desdiferenciação celular e a indução de calo em araçazeiro diferem em função do tipo de explante e concentração de cinetina. Análise histológica evidenciou a participação da região do periciclo vascular e borda dos explantes na calogênese e a diferença na população fenotípica nos explantes foliares. / Myrtaceae has over 3000 species being Acca sp, Eucalyptus sp, Myrcianthes sp, Myrcia sp, Psidium sp, the most representative genus for environmental, economic, pharmaceutical importance, among others. The present study aimed to contribute to the enhancement of propagation techniques of Psidium cattleianum Sab. and Eugenia brasiliensis Lam. by cuttings and sowing conditions in vivo and in vitro. For P. cattleianum, propagation in vivo were tested: IBA doses in the presence or absence of BAP on rooting herbaceous and inducing rooting of leaf; in vitro propagation was tested for organogenesis: Effect of gibberellic acid, immersion time in NaOCl (2%) and water (55 ° C for 10 min) on seed germination; Effect of culture medium composition and culture concentration ratio BAP: ANA on developing shoots. For callus induction, explants disinfection stage of introduction were tested: Pre-treatment with a solution of thiophanate-methyl (49 mg L-1 a.i) mixed with ampicilin (250 mg L-1); effect of immersion time and pH of NaOCl solution. For dedifferentiation were tested: doses of kinetin to induce callus formation in leaf blade and doses of 2,4-D in portions hypocotyl. In vivo for E. brasiliensis we tested the effect of IBA concentration in inducing rooting; in vitro was tested and the effect of GA3 concentration in establishing cuttings. The main results infer that the two species are likely to propagate by cuttings, and to E. brasiliensis technique should be enhanced to increase the percentage of rooting. For in vitro propagation of P. cattleianum the WPM was more suitable for the establishment of cutings. The efficacy of NaOCl in seed disinfection and explants for callus formation is affected by the solution concentration, dwell time and solution pH. The cellular dedifferentiation and callus induction in strawberry guava differ depending on the explant type and concentration of kinetin. Histological analysis showed the pericycle and vascular edge participation of explants on callus formation and phenotypic difference in population in leaf explants.
122

Fatores bi?tico e abi?ticos que influenciam na concentra??o de podofilotoxina

Meira, Paloma Ribeiro 19 September 2013 (has links)
Submitted by Verena Bastos (verena@uefs.br) on 2015-10-14T21:06:54Z No. of bitstreams: 1 Paloma_R._Meira-disserta??o_2013.pdf: 1508066 bytes, checksum: cc4d4d39667159152b8407fa887ad2fa (MD5) / Made available in DSpace on 2015-10-14T21:06:54Z (GMT). No. of bitstreams: 1 Paloma_R._Meira-disserta??o_2013.pdf: 1508066 bytes, checksum: cc4d4d39667159152b8407fa887ad2fa (MD5) Previous issue date: 2013-09-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This paper describes the influence of abiotic and biotic factors in the concentration of secondary metabolites of pharmaceutical interest in medicinal plants, while it aims to answer how these factors influence the concentration of podophyllotoxin and yate?na Leptohyptis macrostachys in vitro, this goal. The specimen Leptohyptis macrostachys was established in vitro from seeds collected in the Chapada Diamantina-Ba; studying the rate of germination rate, the germination and mean germination of seeds grown on MS medium with different concentrations of salts constituents of this medium as well as different concentrations of sucrose and gibberellic acid. Was also studied, such as abiotic factors (culture medium, carbon source temperature, photoperiod and gas exchange) and biological (plant growth regulators) influenced the development (number of shoots and leaves and roots presence of friable callus, compact or oxidized) and production of podophyllotoxin and yate?na. To study the influence of these factors in getting these metabolites, plants were steeped at 40 ? C in ethanol to produce the extract. This was partitioned with water and after a specific treatment, injected into the HPLC. We established a protocol for Leptohyptis macrostachys growing from seeds in ? MS medium supplemented with 1.5% sucrose and 11.55 mM of GA3, there was no significant formation of callus in treatments applied and the concentration of podophyllotoxin was favored when L. macrostachys was grown in ? MS medium supplemented with 1.5% sucrose, closed with PVC film and kept in a growth room at 30 ? C. / Este trabalho descreve a influ?ncia de fatores abi?ticos e bi?tico na concentra??o de metab?litos secund?rios de interesse farmacol?gico em plantas medicinais, ao mesmo tempo que se prop?e a responder como esses fatores influenciam na concentra??o de podofilotoxina e yate?na em Leptohyptis macrostachys in vitro, objetivo deste. A esp?cime Leptohyptis macrostachys foi estabelecida in vitro a partir de sementes coletadas na regi?o da Chapada Diamantina-Ba; estudando o ?ndice de velocidade de germina??o, a germinabilidade e o tempo m?dio de germina??o de sementes cultivadas em meio MS com diferentes concentra??es de sais constituintes deste meio, bem como diferentes concentra??es de sacarose e ?cido giber?lico. Foi estudado tamb?m, como fatores abi?ticos (meio de cultivo, fontes de carbono temperatura, fotoper?odo e trocas gasosas)e bi?tico (reguladores vegetais) influenciaram no desenvolvimento (quantidade de brotos folhas e ra?zes e presen?a de calos fri?veis, compactos ou oxidados) e na produ??o de podofilotoxina e yate?na. Para estudar a influ?ncia estes fatores na obten??o destes metab?litos, as plantas foram maceradas ? 40?C em etanol para a produ??o do extrato. Este foi particionado com ?gua e, ap?s tratamento espec?fico, injetado no CLAE. Foi estabelecido um protocolo de cultivo para Leptohyptis macrostachys a partir de sementes em meio MS ? suplementado com 1,5% de sacarose e 11,55?M de GA3; n?o houve forma??o significativa de calos nos tratamentos aplicados e a concentra??o da podofilotoxina foi favorecida quando L. macrostachys foi cultivada em meio MS ? suplementado com 1,5% de sacarose, fechada com filme de PVC e mantida em sala de crescimento a 30?C.
123

Caracterização in vitro do metabolismo e da absorção intestinal da casearina X / In vitro characterization of metabolism and intestinal absorption of casearin X

Silva, Rodrigo Moreira da 14 March 2016 (has links)
As principais propriedades farmacológicas da Casearia sylvestris, uma espécie de árvore cujas folhas são utilizadas na medicina popular, já foram descritas na literatura. Recentemente foi demonstrada a potente atividade citotóxica in vitro da casearina X (CAS X), o diterpeno clerodânico majoritário isolado das folhas de C. sylvestris, contra linhagens de células tumorais humanas. Apesar dos resultados promissores, sua potente atividade citotóxica in vitro não pode ser extrapolada para uma potente atividade in vivo, a menos que possua boa biodisponibilidade e duração desejável do seu efeito. Tendo em vista que o avanço nas pesquisas de produtos naturais requer a avaliação pré-clínica de propriedades farmacocinéticas, no presente trabalho foi realizada a caracterização in vitro do metabolismo e da absorção intestinal da CAS X, com o objetivo de prever sua biodisponibilidade in vivo. Para os estudos de metabolismo in vitro, foi utilizado o modelo microssomal hepático de ratos e de humanos. Foi desenvolvido um método analítico para a quantificação da CAS X em microssomas, empregando a precipitação de proteínas com acetonitrila no preparo das amostras e a cromatografia líquida de alta eficiência para as análises. O método foi validado de acordo com os guias oficiais da Agência Nacional de Vigilância Sanitária e da European Medicine Agency (EMA). A CAS X demonstrou ser substrato para as reações de hidrólise mediada pelas carboxilesterases (CES) e apresentou um perfil cinético de Michaelis-Menten. Foram estimados os parâmetros de Vmax e KM, demonstrando que o clearance intrínseco em microssomas hepático de humanos foi 1,7 vezes maior que o de ratos. O clearance hepático foi estimado por extrapolação in vitro-in vivo, resultando em mais de 90% do fluxo sanguíneo hepático em ambas as espécies. Um estudo qualitativo para a pesquisa de metabólitos foi feito utilizando espectrometria de massas, pelo qual foi possível sugerir a formação da casearina X dialdeído como produto de metabolismo. Nos estudos de absorção intestinal in vitro foi utilizado o modelo de monocamadas de células Caco-2. Um método analítico por cromatografia líquida acoplada a espectrometria de massas foi desenvolvido e validado de acordo com o EMA, para as etapas de quantificação da CAS X no sistema de células. Os parâmetros cinéticos de permeabilidade aparente absortiva e secretória da CAS X foram estimados em um sistema celular, no qual a atividade hidrolítica da CES foi inibida. Assim, a CAS X foi capaz de permear a monocamada de células Caco-2, provavelmente por transporte ativo, sem a ocorrência de efluxo, mas com significativa retenção do composto dentro das células. Em conjunto, os ensaios in vitro realizados demonstraram a susceptibilidade da CAS X ao metabolismo de primeira passagem, como substrato para as CES específicas expressas no fígado e intestino. / Casearia sylvstris leaves are commonly used by folk medicine and its main pharmacological properties were already described in the literature. Casearin X (CAS X) is the major clerodane diterpene isolated from the leaves of C. sylvestris. Recently, the in vitro cytotoxic activity of the CAS X was demonstrated against human tumor cells lineages. Despite promising results, the CAS X in vitro cytotoxic activity cannot be extrapolated to an in vivo activity, unless the compound has good bioavailability and desirable duration of its effect. The advance in natural products research requires a pharmacokinetic preclinical assessment to justify a therapeutic indication. Thereby, this present work aims to predict the CAS X in vivo bioavailability, by the in vitro characterization of the metabolism and intestinal absorption. The rat and human hepatic microsomal model was used for in vitro metabolism studies. An analytical method for quantification of CAS X in microsomes was developed, employing protein precipitation with acetonitrile for sample preparation and High Performance Liquid Chromatography for analysis. This method was validated in according to Agência Nacional de Vigilância Sanitária and European Medicine Agency guidelines (EMA). CAS X demonstrated to be substrate for carboxylesterases (CES) by hydrolysis reaction, with a Michaelis-Menten kinetic profile. The parameters Vmax and KM was estimated and the intrinsic clearance was 1.7-fold higher in humans than rats. The hepatic clearance was estimated by in vitro-in vivo extrapolation, resulting in more than 90% of the hepatic blood flow for both species. A qualitative study was carried out for the metabolite identification, using Mass Spectrometry, suggesting the formation of casearin X dialdehyde as metabolism product. Monolayer of Caco-2 cells was used for the in vitro intestinal absorption studies. An analytical method by Liquid Chromatography coupled to Mass Spectrometry was developed and validated, according to EMA, for the quantification of CAS X in cells systems. The apparent permeability was estimated in both, absorptive and secretory directions, using cells monolayers with inhibited CES hydrolysis. CAS X was able to cross the Caco-2 cells monolayer, probably by active transport, with no significant efflux, but with a high retention of the compound inside the cells. These findings demonstrated that CAS X is susceptible to first-pass metabolism, as substrate for specific CES expressed in both, liver and intestine.
124

Convergência de vias de desenvolvimento: análise da capacidade de formar órgãos in vitro em mutantes de tomateiro afetando a arquitetura foliar / Convergence of developmental pathways: in vitro analysis of organ formation capacity in tomato mutants affecting leaf architecture

Oliveira, Guilherme Pereira de 03 July 2015 (has links)
O cultivo in vitro de células, tecidos e órgãos vegetais, iniciado no começo do século XX, propiciou avanços no conhecimento científico e biotecnológico. O processo de regeneração in vitro depende tanto das condições de cultivo quanto da base genética dos explantes utilizados. Alguns autores postulam que a regeneração pode ser dividida em etapas e o balanço entre hormônios vegetais é responsável por determinar o destino dos explantes (e.g. formação de raízes, gemas ou calos). Em estudo realizado anteriormente, foi constatada a alta capacidade de regeneração de gemas caulinares adventícias in vitro do mutante Mouse-ears, que apresenta folhas com maior complexidade. Diante disso, neste trabalho outros mutantes que afetam a arquitetura foliar, como entire, procera, clausa, potato-leaf e Mouse-ears, foram avaliados ex vitro e in vitro, no \"background\" da cultivar Micro-Tom (MT). A caracterização fenotípica dos genótipos demonstrou que as mutações estudadas afetam vários outros aspectos do desenvolvimento, além das folhas. Muitas das diferenças observadas ex vitro, são em parte devidas à transição de estágio vegetativo para reprodutivo. Ao analisarmos os resultados de regeneração in vitro (formação de gemas caulinares e raízes adventícias; e crescimento de calos), nota-se que a capacidade organogenética de cada mutante não tem correlação com o grau de complexidade foliar, mas sim com tipo de mutação envolvida. Análises morfológicas de eventos in vitro e ex vitro quanto à formação de gemas caulinares adventícias e do meristema apical caulinar, respectivamente, denotam que ocorrem tanto similaridades quanto disparidades entre os dois processos. Os resultados indicam que provavelmente os mutantes entire (respota constitutiva a auxina por perda de função de um AUX/IAA) e Mouse-ears (super expressão do gene KNOX TKN2) atuam na etapa de indução de raízes e gemas, respectivamente, no processo de regeneração in vitro. Em contra partida, procera (resposta constitutiva a giberelina) atuaria na etapa de aquisição de competência ou retardo do desenvolvimento pós-indução. Além disso, TKN2 demonstrou ter um importante papel na formação de gemas caulinares adventícias in vitro. As vias para a formação de orgãos ex vitro (e.g. folhas, raízes, gemas axilares etc.) são diferentes da in vitro. Apesar disso, vários genes e moléculas recrutados em uma via de desenvolvimento ex vitro podem interferir na organogênese in vitro. / The in vitro culture of plant cells, tissues and organs, started at the beginning of the 20th century, has been leading to scientific and biotechnological advances ever since. The process of in vitro regeneration depends on the growth conditions as well as the genotype of the explant. Several authors postulated that regeneration can bedivided into steps and that the hormonal balance will determinate the fate of the explant (e.g. formation of roots, shoots or callus). In a previous study, it was found that the mutant Mouse-ears, which exhibits a more complex leaf architecture, has high capacity of shoot regeneration. Hence, in the present work others mutants affecting leaf architecture such as entire, procera, clausa, potato-leaf and Mouse-ears were measured ex vitro and in vitro in the MT background. These assessments aimed to investigate if there are similarities in organogenesis between in vitro and ex vitro. The phenotypic characterization of the genotypes showed that these mutations affect several aspects of plant development and not only the leaf architecture. Many differences observed ex vitro are in part due to the transition from vegetative to reproductive phase. When analyzing the results of in vitro regeneration (formation of adventitious shoots and roots; and callus growing) it is noticed that the organogenetic capacity of each mutant have no correlation with the degree of leaf complexity but with the type of mutation involved. Morphological analysis of in vitro and ex vitro events, such as formation of adventitious shoots and shaping of shoot apical meristem, respectively, denotes similarities and divergences between the processes. The results indicate that probably the mutants entire (constitutive response to auxin due to a loss-of-function in an AUX/IAA) and Mouse-ears (overexpression of a KNOX TKN2) act at the induction step of root and shoot, respectively, in the in vitro regeneration process. On the other hand, procera (constitutive response to gibberellin) acts at the competence step or the arrest of the development after induction. Furthermore, TKN2 showed an important role in the formation of in vitro adventitious shoots. The pathways for ex vitro organ formation (e.g. leaf, root, axillary buds, etc.) are different from that for in vitro. Nevertheless, genes and molecules recruited in the pathway of ex vitro development may interfere in the in vitro organogenesis.
125

Field performance and in vitro hardening studies of micropropagated red raspberry

Deng, Ribo January 1992 (has links)
No description available.
126

Development of in vitro toxicity methods for fire combustion products

Lestari, Fatma, Safety Science, Faculty of Science, UNSW January 2006 (has links)
A large range of polymers are used in building and mass transport interiors which released more toxic products during combustion. This work explores the cytotoxicity of selected chemicals and smoke derived from materials combustion. A selection of polymers and fiberglass reinforced polymer (FRP) composites used in building and railway carriage interiors including: polyethylene (PE), polypropylene (PP), polycarbonate (PC), polymethyl methacrylate (PMMA), polyvinyl chloride (PVC), melamine plywood, and two FRPs were studied. A small scale laboratory fire test using a vertical tube furnace was designed for the generation of combustion products. The volatile organic compounds were identified using ATD-GCMS (Automatic Thermal Desorption-Gas Chromatography Mass Spectrometry). The in vitro techniques were developed for human cells exposure to fire effluents including the indirect (impinger) and direct (air/liquid interface using Harvard Navicyte Chamber) exposure. Cytotoxic effects were assessed based on cell viability using a range of in vitro assays. Human skin tissue was also used as preliminary study to assess the toxic effects at the tissue level. A minor change in the cellular function of the skin from the exposure of PMMA combustion products was observed. The combustion study was conducted under different burning stage of fire: non-flaming and flaming combustion. Results suggested that PVC was the most toxic material for both non-flaming (IC50 1.24 mg/L) and flaming combustion (IC50 1.99 mg/L). The degree of toxicity generated depends on the fire stage: non-flaming or flaming combustion. Some materials revealed to be more toxic under flaming combustion (PP, PC, FRPs), whilst others (PVC, PMMA, PE, and melamine plywood) appear to be more toxic under non-flaming combustion. A strong correlation was shown between the change in toxicity as measured by IC50 and TLC and the change in concentration of volatile organic compounds (VOCs) and particulates. A comparison between in vitro data versus published in vivo combustion data indicated the in vitro results to be more sensitive than animal toxicity data. The outcome of this study has the potential for an alternative method to current fire toxicity standard, whilst providing more accurate toxicity information for fire safety professionals, materials manufacturer, building designers and consumer safety data.
127

Misguided hope: a narrative analysis of couples' stories of childlessness despite treatment with assisted reproductive technology

Peters, Kathleen, k.peters@uws.edu.au January 2006 (has links)
Abstract Societal expectations for procreation often result in infertile couples accessing assisted reproductive technology (ART). In the current state of this technology, the successful outcome of the birth of a child does not always occur. This study contributes to nurses' understanding of what it is like for couples to remain involuntarily and permanently childless after infertility treatment has ended, and aims to bring about change in attitudes and practice towards this group. Literature that acknowledges individuality as well as shared experience for couples who remain childless after infertility treatment is scarce. Health professionals may therefore encounter difficulties in providing this group with appropriate support. This research used a qualitative approach informed by feminist perspectives to gather stories of five couples' experiences of childlessness after accessing ART. Individual conversations with both members of the marital partnership were recorded, transcribed and analysed. The study found that due to the societal expectation of procreation, and the falsely elevated 'success rates' of ART, couples often delayed decisions about whether they should persevere with treatment, hence reducing the possibility of exploring alternative methods of parenting. As well as highlighting the ambiguity of the term 'success', the study suggests that the hope that technology brings childless couples prolongs decision making and simultaneously serves to compound the sense of failure experienced by these couples. The couples' engagement with ART, as well as their inability to conform to the normative family of parents and their biological children, also contributed to periods of isolation. Following the decision to remain childless, the participants found that setting achievable and challenging goals assisted in re-building their self-esteem, and enhanced the process of adapting to their life without children. Although participant couples expressed obvious grief at remaining childless, they also showed resilience by managing attached difficulties and stigmatisation, and by creating positive future outcomes. For these childless couples, the strength of their relationships was seen as critical in the process of overcoming adversity. This study suggests ART clinics should provide more realistic information to individual couples regarding the likelihood of taking home a baby. Further to this, independent counselling support is recommended for couples prior to and during ART treatment, and when this treatment is ceased.
128

The effect of paternal heat stress on the development of preimplantation embryos in the mouse / by Bi-ke Zhu.

Zhu, Bike January 2002 (has links)
"July 2002" / Bibliography: leaves 185-247. / xvi, 247 leaves : ill., plates (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / "Paternal heat stress has been reported not only to damage spermatogenesis, endocrine and biochemical functions of testicular tissues, but also to affect the development of preimplantation, implanting and post-implantation embryos in both animals and humans. However, the relationship between the development of preimplantation embryos and the extent of damage of germ cells during heating has not been considered in detail and the molecular mechanisms underlying the effect of paternal heat stress on the development of embryos have not been investigated. These issues form the focus for the studies presented in this thesis. All work was undertaken in mice, using F1 C57/CBA progeny." -- Abstract / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Science, 2002
129

Sorghum tannins: Interaction with Starch and its Effects on in vitro Starch Digestibility

Ribeiro de Barros, Frederico 14 March 2013 (has links)
Most of the calories in cereal foods come from starch. Decreasing starch digestibility is fundamental to prevent obesity and diabetes. This study investigated interactions of condensed tannins (proanthocyanidins-PA) and other sorghum phenolic compounds with starch molecules and their effect on in vitro starch digestibility. High tannin (predominant in large molecular weight PA, 80%), black (monomeric polyphenols) and white (low in polyphenols) sorghum phenolic extracts were cooked with starches varying in amylose content. Starch pasting properties, polyphenol profile and in vitro starch digestibility were evaluated. Unlike other treatments, samples with tannin phenolic extracts had significantly (P ≤ 0.05) lower setback in the test using a Rapid Visco Analyser (RVA) compared to control. The same treatments had the least extractable phenol and PA contents after cooking with all starches. These evidences suggest interactions between starch molecules and PA. Furthermore, after mixing tannin phenolic extracts with pure amylose/amylopectin, extractable polymeric PA was in much lower concentration (62% less) in presence of amylose compared to amylopectin. This drop in concentration increased to 85% when purified tannin extract (90% polymeric PA) was used. This indicates a stronger interaction between amylose and large molecular weight PA. When high amylose starch was used in an autoclave cooking/cooling technique, the RS content of control (26.4%) was similar (P > 0.05) to samples with black phenolic extracts (27%); samples with tannin phenolic extracts increased RS to about 40%. The RS increased to 46% when purified tannin extract was used. All these evidences suggest that sorghum condensed tannins, specifically the polymeric PA, directly interacted with amylose, increasing RS content, whereas the monomeric polyphenols did not. This study opens opportunities to use tannin sorghum to develop products for diabetics and weight control, high in dietary fiber and natural dark color. In the other part of this project, polyphenols from black and tannin sorghum bran were extracted using an Accelerated Solvent Extractor (ASE) and eco-friendly solvents such as water, and mixtures ethanol/water. ASE at 120 and 150 degrees C using 50 and 70% ethanol/water was efficient in extracting as much phenols (45 mg GAE/g) and 12% more antioxidants (628 μmol TE/g) from black sorghum compared to conventional methods using aqueous acetone and acidified methanol. Therefore, ASE extracts from black sorghum could be used in beverages and in colorants containing high antioxidant content.
130

Microplitis croceipes (Hymenoptera: Braconidae): A Life History Study and in vitro Rearing

McLoud, Laura Ann 2011 August 1900 (has links)
Microplitis croceipes (Hymenoptera: Braconidae) is an endoparasitoid and potential biological control agent of the tobacco budworm, Heliothis virescens (Lepidoptera: Noctuidae), an agricultural pest. The first objective of the following research was to amend current larval life history descriptions of M. croceipes. Larval head capsule width measurements were used to distinguish instar, and exuvium in abdominal cavities of post-egression hosts were indicative of a molt during parasitoid egression. Data revealed the larvae of M. croceipes pass through five instars, rather than three, as is indicated in the literature. The second objective was to investigate the suitability of potential artificial diets to be used in in vitro rearing of M. croceipes larvae. Three concentrations each of glucose, trehalose, and protein, as well as a combination diet (derived from initial diet trials) were tested. Growth, molting, and death were noted for each diet, and data indicated that diet had a significant effect for each performance measure (p = 0.0000, p < 0.0001, p < 0.0001, respectively). Data also indicated that trehalose and protein were more vital to larval parasitoid development (growth and molting) than was glucose, but no larvae were reared passed the second instar on an artificial diet. The final goals of the research were to evaluate the plausibility of rearing M. croceipes larvae to adulthood in vitro and to investigate post-egression host defensive behavior. Larvae were dissected from their hosts just prior to egression and placed in a cell culture plate in previously collected host hemolymph. Larvae were able to initiate pre-egression behavior in an in vitro environment, and a small percentage (6.67%) exhibited ecdysial splitting of the cuticle, however, no larvae were able to make the final molt in vitro. Post-egression hosts exhibited defensive behavior that may suggest they play a role in protecting pupating parasitoids. When the parasitoid exuvium was pulled from the egression wound in the host, hemolymph loss occurred and duration of the defensive behavior significantly decreased (p < 0.0001), indicating the exuvium acted to plug the egression wound, which prevented the host from bleeding to death and made it possible for the host to exhibit defensive behavior.

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