Classical theories of how animals make mate choices have focused on each sex's inherited preferences for the other sex's traits or behaviours. The present thesis was undertaken to investigate how social factors play a role in determining an animal's choice of mate. In the series of experiments reported here, 'focal' female and male Japanese quail were given the opportunity to observe another quail (a 'model') of the same sex mating with a conspecific of the opposite sex (a 'target'). Results of experiments described in chapters 2 and 3 revealed that focal females: (1) displayed an increased tendency to affiliate with male targets that they had observed mating with model females, and (2) found a target male more attractive if he had been observed just standing near another female. In Chapter 4, social influences or male mate choice were investigated. Focal males: (1) exhibited a decrease in their preference for female targets that they had observed mating with model males, and (2) showed a decrease in preference for a female target only if she had been seen mating with or being courted by a model male, not simply standing near him. Finally, in chapter 5, it was determined that for quail of both sexes, affiliation time was a reliable predictor of focal subjects' actual choice of a mate. Taken together, these results are consistent with the hypothesis that females gain benefits from attending to the mate choices of other females, whereas for males there is a cost associated with mating with a female that had recently muted with another male. / Thesis / Doctor of Philosophy (PhD)

Understanding what restricts vital rates is crucial in conservation efforts. For migratory birds, vital rates can be impacted by conditions experienced throughout the year. Migratory shorebird populations are rapidly declining, including populations of Dunlin (<i>Calidris alpina arcticola</i>), an Arctic-breeding shorebird. Prior adult survival estimates (0.41– 0.60) appeared insufficient to maintain a stationary population, however, it was unclear if estimates were reflective of bias or a real survival signal. Additionally, C. a. arcticola mate fidelity has yet to be determined, and because demographic rates can be linked to breeding ecology, understanding factors affecting both adult survival and mate fidelity might illuminate specific constraints on demographic rates for this species. I used a Barker (1997) model to estimate true survival (unbiased relative to fidelity) rates of adult C. a. arcticola using 19 years (2003 – 2021) of mark-recapture data and environmental data, collected from a breeding area, Utqiaġvik, Alaska, U.S.A. Breeding site data were supplemented with resighting observations and habitat data from non-breeding sites in eastern Asia (Japan, China, Taiwan). I examined breeding site environmental (temperature, snow melt date, precipitation) and ecological (predator abundance and predator-prey cycles, food resources, shorebird nesting density) in conjunction non-breeding site habitat (area of intertidal extent) effects on survival estimates. True survival averaged 0.62 (95% C.I. 0.50 – 0.72), and marginally declined six percent throughout the study period. Survival was positively related to intertidal extent on non-breeding grounds and heavy precipitation events on the breeding grounds; with precipitation influence on survival likely being driven by outliers in the data. I propose intertidal habitat (which declined 22% across 19 years) is likely a core driver of low survival rates. These results enforce that low adult survival rates are suppressing C. a. arcticola populations, as while other demographic rates (reproductive output, breeding propensity) are comparable with North American Arctic-breeding C. alpina subspecies, both adult survival rates and estimated population growth remain relatively lower. I emphasize that conservation efforts should be focused at areas currently losing intertidal habitat within the East Asian-Australasian Flyway to mitigate future C. a. arcticola declines. Using C. a. arcticola breeding site data, I tested four hypotheses to understand divorce in C. a. arcticola: the better option hypothesis, in which divorce improves reproductive success by obtaining a higher quality mate; the habitat mediated hypothesis, when divorce might occur if an opportunity exists to nest at a higher quality site than the prior breeding season; musical chairs, in which divorce is related to site-specific settlement choices upon arrival to the breeding grounds; and bet-hedging, in which divorce is more likely when mates arrive to the breeding grounds asynchronously, and an individual will pair with a new mate to avoid the cost of waiting for a previous mate to return to it. I used a logistic regression model to investigate effects on C. a. arcticola divorce with environmental and ecological factors that might influence divorce. Of the females nesting in consecutive years, 20% of those females divorced; and in the cases of males nesting in consecutive years, 55% of those males divorced. Both sexes were more likely to divorce when there was greater availability of experienced mates on the breeding grounds, significantly in males (β = 0.81, 95% CI = -0.65 – 2.28), compared to females (β = 1.27, 95% CI = 0.28 − 2.25). The results indicate males divorce behavior supports the better-option hypothesis, in which males divorced to "upgrade" to a mate with more breeding experience than their prior mate. However, male divorce behaviors also supported the bet-hedging hypothesis, as evidenced by similar nest initiation dates between divorced and reuniting males, which indicated males may divorce to avoid reproductive costs associated with waiting for a later-returning mate. Female divorce behavior was linked to either the habitat-mediated hypothesis, in which individuals attempt to acquire better habitat than their prior breeding site, or the better-option hypothesis, both evidenced by divorced females improving their reproductive success from the prior year. Divorced females exhibited higher egg success rates compared to divorced males, indicating females are likely the sex breaking the pair. Together, the results present novel information concerning C. a. arcticola. The first chapter presents direct connections between intertidal habitat loss and lower adult survival, and enforce calls for restoration of Asian intertidal areas along flyways to aid the conservation of migratory shorebirds. The second chapter provides the first estimates of C. a. arcticola mate fidelity and insight towards better understanding migratory shorebird breeding ecology. / Master of Science / Our understanding what influences bird populations is frequently related to identifying factors affecting population dynamics and breeding ecologies. Arctic-breeding migratory shorebirds face unique circannual challenges, as the Arctic is experiencing rapid and unprecedented climate change. Additionally, climate change and coastline development can significantly alter coastal environments used by shorebirds during non-breeding periods. Dunlin (<i>Calidris alpina arcticola</i>) are Arctic-breeding shorebirds that migrate annually to non-breeding areas in East Asia. Previous estimates of C. a. arcticola adult survival rates raised concerns about population stability, but it was unclear if these estimates reflected real survival patterns. Beyond survival rates, mate fidelity and implications of mate fidelity for this subspecies remains unknown. Understanding mate fidelity can clarify demographic constraints, as it can have significant implications for breeding dispersal and population structure. I used 19 years of data collected from a C. a. arcticola breeding site to obtain unbiased estimates of adult survival, factoring in fidelity to the breeding site, and, considered environmental and ecological variables from both breeding and non-breeding grounds thought to influence adult survival. Results indicated a slightly higher adult survival rate than previously estimated, but still low enough to remain depressive on population growth. Survival was positively linked to non-breeding habitat (intertidal areas). These results emphasize the need for conservation efforts aimed at intertidal areas along East Asian migratory routes and non-breeding locations. Using this same long-term dataset, I tested different divorce hypotheses to understand why C. a. arcticola divorce: which could be for better mates (better-option), to acquire better nesting habitat (habitat-mediated), because of settlement strategies upon arrival to breeding grounds (musical chairs), or due to differences in arrival timing to the breeding grounds between pair members and avoiding associated delayed reproductive costs while waiting for a prior year's mate (bet-hedging). I modeled divorce based on sex, individual breeding experience, arrival timing, annual reproductive output, and prior-year's seasonal environmental conditions at the breeding site. Divorce rates were higher in years when higher variation in mate quality were available breeding site, especially among males, who "upgraded" for higher-quality mates (better-option). Divorce behaviors also supported the bet-hedging hypothesis (divorce happens to avoid the cost of waiting for a previous mate to return) for males, and the habitat-mediated (divorce happens to acquire better breeding site habitat than the prior year) strategy in females. Divorced females had better hatching success then divorced males in the year of divorce, indicating they were the sex initiating divorce most frequently. This study provides insight into C. a. arcticola breeding ecology and demography, offering the first estimates of both true adult survival and mate fidelity rates for this subspecies. These findings contribute to our understanding of migratory shorebird dynamics and aim to support conservation efforts for migratory shorebird populations.

The data gathered for this exploratory study of parental influence on mate selection supported the thesis that parents influence their childrens' mate selection. Fifty married university students were interviewed and fifty-five of their parents returned mailed questionnaires. Although students indicated that they, themselves, had chosen their spouses, seventy per cent of the students perceived parental influence on their choice of mate. Thirty-six per cent of the parents felt that they had influenced their childrens' choice of a spouse. It was postulated that parents through socialization and by acting as validators of their childrens' choices--by encouraging approved matches and discouraging opposed matches, exerted influence. Three types of influence were found which were classified according to BurKess' typology of parental influence: controlling of social contacts, opposition to disapproved matches, and the child's conscious desire to choose a mate his or her parents would approve. In these ways, by determining an appropriate field of eligibles, the parents directly and indirectly had input into their childrens' choice of mates. The great majority of parents met the individuals dated and/ or courted by their children. Of these parents, most approved of the individuals met; if they disapproved they communicated their feelings very overtly. The “individual choice" explorations of mate selection are questioned, and it is suggested that a study with a larger representative sample be undertaken to ascertain parental influence on mate selection for the population. / Master of Science

The aim of this research was to identify differences in personality that correlate with attraction to potentially psychopathic individuals. A sample of 587 (437 female) undergraduate psychology students at the University of Central Florida were recruited for participation. The participants were presented with a fictional dating profile of a psychopathic individual of the other sex. Participants were asked to rate their attraction to the individual portrayed in the dating profile, and proceeded to complete a series of personality instruments. Data was analyzed using a multiple regression analysis at a 0.05 confidence interval. High levels of attraction were significantly predicted by scores on psychopathy, need for affiliation, empathy, and impulsivity.

Theoretical models of sexual selection assume that female mating preferences are fixed and variation found between individuals resulting solely from allelic variation at specific loci coding for sexual preferences. For the last decade, an increasing number of studies have demonstrated that individual phenotypic variation in preferences was common across a wide range of taxa and induced by the environmental context and the females’ condition. Further, developmental stages of life are crucial in the formation of behaviours in general and have proven to be determinant to learn sexual preferences in some species that dispense care for their young. However, very little studies have analysed how the early social and physical environments shape female mate choice in species that lack parental care. In this thesis, I used guppies (Poecilia reticulata), firstly, to investigate the influence of various aspects of the social environment provided by males during two ontogenetic phases. Secondly, I explored whether learned preferences in a foraging context during development could be transferred into a mating context. Considering the early social environment, I explored three distinctive features potentially displayed by males and that females might experience while growing. Females were reared with different values of a sexual trait not genetically preferred in the population (orange colour) and different values of a trait for which they had innate predisposition (total colour area). In both cases, females were exposed to the different treatments for the whole developmental period or for its later phase. My results indicated that females changed their sexual behaviours in response to both type of traits experienced, reversing sometimes their genetic preferences. Moreover, the timing of exposure seemed to be a key factor in the acquisition of preferences as females exposed only to the later part of development with different values of total colour didn’t rely anymore on colour patterns to discriminate among males. In a third body of experiment, I examined whether the overall phenotypic variance exhibited by males during whole development, independently of the values of a specific sexual cue, mediated female’s behaviours. In a context of high variance, female became choosier relatively to those experiencing less variance. As a response, males switched mating tactics and attempted more forced copulations. In its final part, my thesis searched for a link that might have arisen, owing to developmental conditions, between preferences using the same sensory modality in two behavioural contexts. Maturing females were given food that was associated to a certain colour and subsequently tested for both their coloured preference in a foraging and a sexual context. Although no foraging preference for the corresponding colour was detected, females that experienced a yellow stimulus preferred yellower males compared to females with other experiences. Taken together these results suggest that developmental conditions and especially the social environment play a pivotal role in the process of mate choice. Under some circumstances, learned mate preferences override genetically-based preferences highlighting the importance of non-genetic mechanisms. Accordingly, it is urgent to integrate in the study of sexual selection and reproductive isolation this dimension. In guppies, for instance, the effect of early social life might contribute to the maintenance of colour pattern polymorphism found in males.

Curling är unik i avseendet att man kan påverka stenens bana efter att den släppts av spelaren. Beroende på trycket (Kg) och frekvensen (soptag/min) man kan applicera under sopmoment påverkas stenen olika mycket. Syftet med studien är att undersöka om curlingspelare med greppsula är mer uthålliga beträffande trycket och frekvensen vid sopning under flera stenar jämfört med curlingspelare som sopar med glidsula. Studien är en experimentellundersökning med två grupper och urvalet bestod av 17 män, 16–23 år, som spelade curling i någon av de två högsta serierna i Sverige. Undersökningsdeltagarna sopade tre stenar i följd under 15 sekunder med 50 sekunders vila mellan varje sten. Utrustningen som användes var mätinstrumentet (Broom-Mate), pulsklockan (Pm25, Beurer: Tyskland) och (Borg-Rpe-skalan). Resultatet från studien tyder på att det inte finns några signifikanta skillnader mellan att sopa med greppsula eller glidsula gällande förmågan att applicera och bibehålla trycket och frekvensen under tre sopade stenar. / Curling is unique in the way that you can affect the path of the curling rock after it´s been released. Depending on the amount of force (Kg) and frequency (strokes/min) of the sweeping motion it affects the path differently. The purpose of this study is to exam if curling players sweeping with gripper on are better regarding sustaining their force and frequency sweeping multiple stones compared to curling players sweeping with sliders on. The report is an experimental study with two groups. The selection consisted of 17 men, aged 16-23 years, regularly playing in one of the two top leagues in Sweden. The participants swept three stones in a row during 15 seconds with 50 seconds rest in between the stones. Equipment used during the collection of data were the (Broom-mate), heartrate monitor (Pm25, Beurer: Germany) and (Borg-RPE-scale). The results from the report suggest that there´s no significant difference between sweeping with gripper or slider on, regarding the ability to apply and sustain their force and frequency during three rounds of sweeping.

A alimentação humana necessita de nutrientes essenciais em sua dieta de forma balanceada. A carne é uma perfeita fonte de proteína e suplemento de ferro, zinco e outros micronutrientes como as vitaminas. O consumo de carne deve ser cada vez maior, já que a produção mundial que em 2012 era de 302 milhões de toneladas, hoje é de aproximadamente 319 milhões. Concomitantes ao aumento no consumo mundial de carne surgem dois problemas. A carne e produtos cárneos induzem ao estress oxidativo, por meio do ferro catalizado na formação de espécies reativas ou por ingestão de hidroperóxidos orgânicos durante a digestão. Tais espécies podem acarretar deterioração do produto, afetando seu tempo de exposição em prateleira e comprometendo sua qualidade, interferindo em questões econômicas. Dentro de um contexto de saúde pública, estas espécies podem gerar desequilíbrio celular, mutações genéticas e danos cromossômicos, desencadeando doenças degenerativas no organismo humano. Uma dieta balanceada deve ser inspirada na natureza. Por meio da evolução as plantas desenvolveram, devido ao estress oxidativo, a capacidade de produzir compostos bioativos como xantinas e compostos fenólicos, como mecanismo de proteção. A Erva-mate, Ilex paraguariensis contém alta quantidade relativa destes compostos, que atuam como antioxidantes, os quais podem ser usados como aditivos na alimentação, com o objetivo de modificar o estado redox do organismo animal. Isto pode induzir mudanças no metabolismo, afetando a composição do tecido muscular e, consequentemente, a qualidade da carne. O presente trabalho se propôs a investigar as mudanças no perfil de composição dos metabólitos polares e seu impacto na estabilidade redox da carne de frangos de corte que tiveram suas dietas suplementadas com diferentes níveis de extrato de erva-mate na ração. A adição de tais extratos claramente promoveu uma mudança quantitativa na composição de metabólitos polares da carne como mostrado a partir de análises de 1H RMN e impactou positivamente na estabilidade redox segundo análises por spin-trapping RPE. Por fim, a adição de 0,075% m/m de extrato de erva-mate na alimentação de frangos de corte mostrou-se como o tratamento mais indicado, promovendo mudanças bioquímicas no metabolismo do animal, melhorando a estabilidade oxidativa da carne, seu tempo de exposição em prateleira e um produto de maior qualidade e segurança para o consumidor. / Human food needs to supply essential nutrients in balance. Meat is a perfect protein source and supplies iron and zinc and many micronutrients like vitamins. The consumption of meat would increase in the next years because the global production in 2012 was 302 millions of tons, and actually is 319 millions of tons, approximately. Concomitantly with the increasing of global consumption of meat, two problems arise. Meat and meat products also hold the risk of inducing oxidative stress through iron catalyzed formation of reactive species or by ingestion of organic hydro peroxides during digestion. These species can cause the deterioration of the product, affecting its shelf-life, compromising its quality and influencing economic aspects. In the context of the public health, these species can generate cellular imbalance, genetic mutations, and chromosome damages, resulting in degenerative diseases of the human organism. A balanced diet should be inspired by Nature. Through evolution, oxidative stress made plants to produce bioactive compounds like xanthines and phenolic compounds to protect against oxidative stress. Yerba-mate, Ilex paraguariensis, contains relative high amounts of these compounds that act as antioxidants, which may be use as a feeding additive in order to modify the redox status of the animal organism. This may induce change in the animal metabolism, affecting the muscle tissue composition and thus the meat quality. The present investigation aims to screen changes in the polar metabolites composition and its impact on the redox stability of meat from broilers fed with different levels of yerba-mate extract as feed additive. The addition of mate extract to broilers feed clearly provided a quantitative change in the polar metabolites of meat as shown by 1H NMR analysis and impacted positively in the redox stability of meat as probed by spin-trapping EPR analysis. In conclusion, addition of 0.075 % w/w of yerba-mate extract to the broilers feed shown up like the best treatment because it produced biochemical changes in the animal metabolism improving the oxidative stability meat which may positively increase the product shelf-life and a safer and higher quality product to the consumer.

Introdução: Atualmente observa-se aumento das complicações cardiovasculares, como alterações no perfil lipídico e oxidativo, em indivíduos com HIV/AIDS, devido à própria infecção, bem como aos diferentes componentes da terapia antirretroviral (TARV). Vários estudos, em outras populações, mostram que os flavonóides presentes no cacau (Theobroma cacao) e erva mate (Ilex paraguariensis) podem melhorar a função cardiovascular devido às suas propriedades antioxidantes e hipolipemiantes. Objetivo: Avaliar o efeito da ingestão de chocolate e erva mate no perfil lipídico e oxidativo de indivíduos com HIV/AIDS em TARV. Metodologia: Ensaio clínico do tipo cross-over, aleatorizado, cego e controlado com placebo envolvendo 89 voluntários, de 28-59 anos de idade, em tratamento regular com TARV por, no mínimo, seis meses e com carga viral <500 cópias/mL. Os voluntários consumiram 65g de chocolate em barra (chocolate preto contendo 36g de cacau e placebo) e 3g de chá (erva mate solúvel e placebo) por 15 dias cada, seguido por 15 dias de washout entre cada período de suplementação. Foram avaliadas as seguintes características: perfil demográfico e socio-econômico, variáveis antropométricas, imunológicas, prática de atividade física, perfil lipídico (colesterol total, LDL-c, HDL-c, não HDL-c, triacilgliceróis e índices de Castelli I e II), e oxidação lipídica (LDL eletronegativa e substâncias reativas ao ácido tiobarbitúrico-TBARS). As análises estatísticas do cross-over foram realizadas através de análises de variância (ANOVA) utilizando o procedimento pkcross no software Stata versão 11.0. Também se realizou teste t de Student pareado entre os parâmetros no baseline e após consumo dos suplementos de interesse (chocolate preto e erva mate). Considerou-se significante p<0,05. Resultados: Os pacientes eram na maioria do sexo masculino (62,9 por cento), com média de idade de 44,6 (±7,1) anos. Observou-se média de 13,2 (±4,8) anos de diagnóstico de HIV/AIDS, com 10,6 (±5,1) anos de uso de TARV. Não houve diferença significativa comparando as médias das variáveis do perfil lipídico e oxidativo entre as diferentes suplementações (chocolate preto, erva mate e placebos) por ANOVA. Entretanto, na comparação entre as variáveis no baseline e após consumo de chocolate preto, pelo teste t de Student pareado, observou-se aumento de colesterol total (p=0,005), HDL-c (p=0,019) e LDL-c (p=0,002). Conclusão: Este é o primeiro estudo clínico que avaliou o efeito da ingestão de chocolate (cacau) e chá mate (erva mate) no perfil lipídico e oxidativo de indivíduos com HIV/AIDS em TARV. No presente estudo, o consumo tanto do cacau quanto da erva mate por 15 dias cada, não foi suficiente para melhorar o perfil lipídico e oxidativo destes indivíduos, apesar do aumento de HDL-c observado após o consumo do chocolate preto. Tal resultado neste grupo de indivíduos pode ser devido ao seu metabolismo diferenciado, o qual sofre alterações não apenas pela própria infecção, mas também pela TARV, a quantidade e biodisponibilidade dos flavonóides nos suplementos e ao tempo de intervenção / Introduction: Nowadays there is an increase of cardiovascular complications, such as changes on the lipid and oxidative profile of individuals with HIV/AIDS due to the infection itself, as well as to the different components of the antiretroviral therapy (ART). Several studies in other populations, show that flavonoids in cocoa (Theobroma cacao) and yerba mate (Ilex paraguariensis) may improve cardiovascular function due to its antioxidant and lipid lowering. Objective: To evaluate the effect of chocolate intake and yerba mate on the lipid and oxidative profile of individuals with HIV/AIDS on ART. Methodology: Randomized, placebocontrolled, blinded cross-over trial involving 89 volunteers ages 28-59 years, in ART for at least six months and with viral load <500 copies/mL. The volunteers consumed 65g chocolate bar (36g dark chocolate containing cocoa or placebo) and 3g of tea (yerba mate soluble and placebo) for 15 days each, followed by 15 days washout period before the subsequent treatment. The following characteristics were evaluated: demographic and socio-economic, anthropometric, immunologic, physical activity, lipid profile (total cholesterol, LDL-c, HDL-c, non-HDL-c, triglycerides and Castelli I and II indices), and lipid oxidation profile (electronegative LDL and thiobarbituric acid reactive substances- TBARS). Statistical analyzes were performed by the cross-over analysis of variance (ANOVA) using the procedure pkcross in Stata version 11.0. The paired Students t-test was also utilized. A p value <0.05 was considered significant. Results: Patients were mostly male (62.92 per cent) with a mean age of 44.6 (± 7.1) years. The mean time of HIV/AIDS diagnosis was 13.2 (± 4.8) years, with 10.6 (± 5.1) years of ART. There was no statistically significant difference comparing the lipid profile and lipid oxidation profile of the individuals under the different supplementations (dark chocolate, yerba mate, and placebo) by ANOVA. However, comparing the variables in the baseline period and after consumption of dark chocolate by the paired Students t-test, there were increases in total cholesterol (p=0.005), HDL-c (p=0.019) and LDL-c (p=0.002). Conclusion: This is the first clinical study that evaluated the effect of chocolate (cocoa) and mate tea (yerba mate) consumption on lipid and oxidative profile of individuals with HIV/AIDS on ART. In the present study, daily consumption of neither cocoa nor yerba mate for 15 days was sufficient to improve lipid and oxidative profile of these individuals, despite the increase in HDL-c observed after consumption of dark chocolate. Such an outcome in this group of individuals can be distinguished due to its metabolism, which is altered not only by the infection itself, but also by the ART, the amount and bioavailability of flavonoids in supplements and timing of intervention

Está bem estabelecido que o diabetes melito está associado a uma série de distúrbios clínicos que envolvem a alteração no metabolismo de carboidratos, proteínas e lipídios. Tem-se observado aumento importante da morbidade e mortalidade associadas a esta doença, sendo que dentre as causas, em ambos os tipos de diabetes (1 e 2), têm-se o aumento de fatores de risco, como o sobrepeso ou obesidade e o estilo de vida sedentário. A erva-mate (Ilex paraguariensis) tem apresentado grande potencialidade para utilização preventiva e terapêutica no diabetes graças à atividade biotiva dos seus compostos (metilxantinas, polifenóis e saponinas), capazes de alterar o metabolismo tecidual energético tanto em protocolos experimentais com animais de laboratório quanto humanos. Assim sendo, o objetivo deste trabalho foi elucidar o efeito da administração do chá de mate em ratos Wistar diabéticos, tendo como foco o metabolismo tecidual muscular e hepático. Para tanto, ratos Wistar machos foram submetidos a indução do diabetes experimental com injeção de estreptozotocina (65 mg/kg, i.p.) e posteriormente tratados com o extrato aquoso de erva-mate através da água de beber por 30 dias. Ao final do tratamento, os animais foram eutanasiados e os tecidos (soro, músculo, fígado e tecido adiposo retroperitoneal e epididimal) foram coletados para análise. / There is a well known relationship between metabolic disturbances and clinical events related to diabetes and a dangerous prevalence increase worldwide for both types of this disease (diabetes type 1 and 2). This enhancement is caused by overweight, sedentary lifestyle and other risk factors associated to occidental habits. Yerba-mate (Ilex paraguariensis) has been presented a potential use to preventive and therapeutical aspects of diabetes due to its bioactive fractions (methylxanthines, saponins and polyphenols), which have a capability to improve energetic metabolism in murine models and human. The aim of this study was to elucidate the effect of yerba-mate on hepatic and muscle energetic metabolism of diabetic rats. To perform the diabetes inducing protocol Wistar rats received streptozotocin (65mg/kg i.p.), then the mate treatment protocol was performed daily and offered as a drink tea. After a 30-day treatment, the animals were weighed and euthanized to evaluate metabolic parameters on liver, adipose tissue, muscle and serum.

O grande acúmulo de saponinas nos frutos imaturos de erva mate permite considerá-los uma fonte de matéria prima abundante e ainda não explorada para obtenção de saponinas. As saponinas são conhecidas como tensoativos naturais, sendo utilizadas pelas suas propriedades emulsificantes e farmacológicas. O presente estudo teve como principal objetivo avaliar o uso de técnicas de extração emergentes, como Extração assistida por Ultrassom (US), Campo Elétrico Moderado (CEM) e Extração por Fluido Supercrítico (EFS) para a extração seletiva de saponinas a partir de frutos imaturos de erva mate. Foram investigadas três condições de intensidade de ultrassom (565, 423 e 282 W cm-²) e de intensidade de campo elétrico (50, 37,5 e 25 V cm-1) associadas a diferentes temperaturas de operação. A interação das intensidades de ultrassom e de campo elétrico com diferentes temperaturas foi avaliada através do método de superfície de resposta. Para as extrações por fluido super e sub crítico foram utilizadas três condições de pressão (10, 20 e 30 MPa) e posteriormente sua correlação com diferentes vazões de solvente (1,62; 2,22 e 2,78 x10-4 kg s-1) e temperatura (30, 40 e 50 °C) foi investigada através do métodos de superfície de resposta. Curvas de rendimento das extrações em função do tempo foram levantadas para as condições ótimas de campo elétrico e intensidade de ultrassom (37,5 V cm-1 e 565 W cm-², respectivamente) a 40°C. As curvas foram modeladas matematicamente, com ajuste satisfatório, por modelos cinéticos de 1ª e 2ª ordem e também por um modelo difusivo baseado na 2ª Lei de Fick. Para extração supercrítica, foi construída a curva de extração para a condição de 10 MPa e 40 °C e esta curva foi modelada matematicamente. Assim, foram estimados parâmetros relacionados à transferência de massa, importantes para a compreensão fenomenológica dos processos extrativos. Nesse estudo, a extração com CO2 supercrítico mostrou-se tecnicamente viável para a obtenção de saponinas, sendo mais seletiva em relação aos processos por campo elétrico e ultrassom. Os ensaios com ultrassom e campo elétrico conseguiram gerar extratos brutos com até 68,30 e 64,26 μgilexmg-1extrato em massa de equivalente de saponina por massa de extrato, respectivamente. Os extratos obtidos com fluido supercrítico apresentaram elevada seletividade para saponinas, gerando extratos brutos com até 100,9 μgilex mg-1 extrato de saponina por massa de extrato. A pressão de operação não apresentou efeito tanto no rendimento global de extrato quanto no de saponina. / Considering the substantial amount of saponins in unripe yerba mate fruits, they are an abundant source of raw material not exploited yet. Saponins are known as natural surfactants, being used by their emulsifier and pharmacological properties. This study aimed to evaluate emergent extraction techniques such as Ultrasound (US), Moderate Electric Field (MEF) and Supercritical Fluid Extraction (SFE) for the selective extraction of saponins from unripe fruits of yerba mate. Three power conditions (565, 423 and 282W cm-2), electric field intensities (50, 37.5 and 25 V cm-1) and pressure conditions (10, 20 and 30 MPa) were initially assayed for US, MEF and SFE respectively at 40 °C. Power and electric field intensity were found to affect the saponins yields, thus, their correlation with different temperatures were evaluated with a factorial design. At the optimal condition, US and MEF saponins yields were 6.42% and 6.83% (%gilex gextract-1). Extraction yield curves were raised for optimum conditions of electric field and ultrasound power (37.5 V cm-1 and 565 W cm-², respectively). Three different kinetic models were used to model mathematically the overall extraction curves, namely a first-order, second-order, and a mass transfer model based on Fick’s Law. The operating pressure had no effect on either the overall brute extract or saponins yield for SFE. Although the extracts obtained with supercritical fluid showed low brute extracts yields, it was highly selective for saponins yielding up to 10.09%. For supercritical extraction, the extraction curve for 10 MPa and 40 °C was assayed and the experimental data fitted by a mathematical model. Parameters related to mass transfer, important for understanding of the extractive processes, were successfully estimated. In this study, the extraction with ultrasounds, electric field and supercritical CO2 were shown to be technically viable to obtain saponins from unripe yerba mate fruits, being EFS more selective than the other technics studied.