The Origin and Early Evolution of Life

What is life? How, where, and when did life arise? These questions have remained most fascinating over the last hundred years. Systems chemistry is the way to go to better understand this problem and to try and answer the unsolved question regarding the origin of Life. Self-organization, thanks to the role of lipid boundaries, made possible the rise of protocells. The role of these boundaries is to separate and co-locate micro-environments, and make them spatially distinct; to protect and keep them at defined concentrations; and to enable a multitude of often competing and interfering biochemical reactions to occur simultaneously. The aim of this Special Issue is to summarize the latest discoveries in the field of the prebiotic chemistry of biomolecules, self-organization, protocells and the origin of life. In recent years, thousands of excellent reviews and articles have appeared in the literature and some breakthroughs have already been achieved. However, a great deal of work remains to be carried out. Beyond the borders of the traditional domains of scientific activity, the multidisciplinary character of the present Special Issue leaves space for anyone to creatively contribute to any aspect of these and related relevant topics. We hope that the presented works will be stimulating for a new generation of scientists that are taking their first steps in this fascinating field

Recent advances in β-galactosidase and fructosyltransferase immobilization technology

The highly demanding conditions of industrial processes may lower the stability and affect the activity of enzymes used as biocatalysts. Enzyme immobilization emerged as an approach to promote stabilization and easy removal of enzymes for their reusability. The aim of this review is to go through the principal immobilization strategies addressed to achieve optimal industrial processes with special care on those reported for two types of enzymes: β-galactosidases and fructosyltransferases. The main methods used to immobilize these two enzymes are adsorption, entrapment, covalent coupling and cross-linking or aggregation (no support is used), all of them having pros and cons. Regarding the support, it should be cost-effective, assure the reusability and an easy recovery of the enzyme, increasing its stability and durability. The discussion provided showed that the type of enzyme, its origin, its purity, together with the type of immobilization method and the support will affect the performance during the enzymatic synthesis. Enzymes’ immobilization involves interdisciplinary knowledge including enzymology, nanotechnology, molecular dynamics, cellular physiology and process design. The increasing availability of facilities has opened a variety of possibilities to define strategies to optimize the activity and re-usability of β-galactosidases and fructosyltransferases, but there is still great place for innovative developments.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Bioinorganic Chemistry

This book covers material that could be included in a one-quarter or one-semester course in bioinorganic chemistry for graduate students and advanced undergraduate students in chemistry or biochemistry. We believe that such a course should provide students with the background required to follow the research literature in the field. The topics were chosen to represent those areas of bioinorganic chemistry that are mature enough for textbook presentation. Although each chapter presents material at a more advanced level than that of bioinorganic textbooks published previously, the chapters are not specialized review articles. What we have attempted to do in each chapter is to teach the underlying principles of bioinorganic chemistry as well as outlining the state of knowledge in selected areas. We have chosen not to include abbreviated summaries of the inorganic chemistry, biochemistry, and spectroscopy that students may need as background in order to master the material presented. We instead assume that the instructor using this book will assign reading from relevant sources that is appropriate to the background of the students taking the course. For the convenience of the instructors, students, and other readers of this book, we have included an appendix that lists references to reviews of the research literature that we have found to be particularly useful in our courses on bioinorganic chemistry

Studies on equine milk and comparative studies on equine and bovine milk systems

The composition of equine milk differs considerably from that of the milk of the principal dairying species, i.e., the cow, buffalo, goat and sheep. Because equine milk resembles human milk in many respects and is claimed to have special therapeutic properties, it is becoming increasingly popular in Western Europe, where it is produced on large farms in several countries. Equine milk is considered to be highly digestible, rich in essential nutrients and to possess an optimum whey protein:casein ratio, making it very suitable as a substitute for bovine milk in paediatric dietetics. There is some scientific basis for the special nutritional and health-giving properties of equine milk but this study provides a comprehensive analysis of the composition and physico-chemical properties of equine milk which is required to fully exploit its potential in human nutrition. Quantification and distribution of the nitrogenous components and principal salts of equine milk are reported. The effects of the high concentration of ionic calcium, large casein micelles (~ 260 nm), low protein, lack of a sulphydryl group in equine β-lactoglobulin and a very low level of κ-casein on the physico-chemical properties of equine milk are reported. This thesis provides an insight into the stability of equine casein micelles to heat, ethanol, high pressure, rennet or acid. Differences in rennet- and acid-induced coagulation between equine and bovine milk are attributed not only to the low casein content of equine milk but also to differences in the mechanism by which the respective micelles are stabilized. It has been reported that β-casein plays a role in the stabilization of equine casein micelles and proteomic techniques support this view. In this study, equine κ-casein appeared to be resistant to hydrolysis by calf chymosin but equine β-casein was readily hydrolysed. Resolution of equine milk proteins by urea-PAGE showed the multi-phosphorylated isoforms of equine αs- and β-caseins and capillary zone electrophoresis showed 3 to 7 phosphorylated residues in equine β-casein. In vitro digestion of equine β-casein by pepsin and Corolase PP™ did not produce casomorphins BCM-5 or BCM-7, believed to be harmful to human health. Electron microscopy provided very clear, detailed images of equine casein micelles in their native state and when renneted or acidified. Equine milk formed flocs rather then a gel when renneted or acidified which is supported by dynamic oscillatory analysis. The results presented in this thesis will assist in the development of new products from equine milk for human consumption which will retain some of its unique compositional and health-giving properties

THE EFFECTS OF EXOGENOUS ENZYME SUPPLEMENTATION ON THE PERFORMANCE, BONE QUALITY, AND NUTRIENT UTILIZATION OF BROILER CHICKENS

Two experiments were conducted to examine the effects of Allzyme® Spectrum supplementation to a reduced nutrient diet on the growth performance, energy and nutrient digestibility and utilization, bone quality, and jejunal digesta viscosity in broiler chickens. Each experiment used 300 one-day old Cobb by-product breeder chicks with 5 treatments, 10 replicates, and 6 birds per replicate cage in a randomized complete block design. The only differences between the two experiments were experiment 1 lasted for 21 days using a corn-soybean meal-based diet and experiment 2 lasted for 22 days using a wheat-soybean meal-based diet. The 5 treatments included a positive control (PC) diet that met or exceeded nutrient Ca (0.8%) and avP (0.4%) and energy (3,050 kcal/kg) requirements of birds of this age, a negative control (NC) diet that consisted of a reduction of 90 kcal/kg ME and 0.15%-point less Ca and P, and the last 3 treatments were varying inclusion levels of Allzyme® Spectrum (150, 200, 250 g/ton, respectively) added to the NC diet. Allzyme® Spectrum (Alltech, Inc., Nicholasville, KY, USA) is an enzyme complex containing xylanase and phytase. Data were analyzed using the GLM procedures of SAS (v 9.4). Simple contrasts were used to compare the PC vs. NC diet and PC vs. enzyme supplemented diets. A post-hoc test was used to generate the coefficients for the polynomial contrasts. Orthogonal polynomial contrasts were used to compare increasing levels of enzyme supplementation on the performance, jejunal digesta viscosity, nutrient digestibility and utilization, and bone mineralization of chickens. In experiment 1, increasing levels of enzyme supplementation resulted in a quadratic increase (P \u3c 0.05) in feed intake (FI), body weight gain (BWG) and feed efficiency (FE) d 9-21 and a linear increase (P \u3c 0.05) in FI d 9-21 and 0-21 and FE d 0-9, 9-21, and 0-21. In experiment 2, FI of chickens from d 9-22 and 0-22 and FE d 9-22 linearly increased (P \u3c 0.05) with increasing level of supplemental Allzyme® Spectrum. There was a quadratic effect (P \u3c 0.05) of enzyme supplementation level on BWG d 9-22 and 0-22 and FE d 9-22 and 0-22. In experiment 2, increasing levels of enzyme supplementation resulted in both a quadratic and linear decrease (P \u3c 0.001) in jejunal digesta viscosity. In both studies, increasing levels of enzyme supplementation resulted in a quadratic increase (P \u3c 0.05) in dry matter and N digestibility and retention as well as, digestible and metabolizable energy and a linear increase (P \u3c 0.05) in P and Ca digestibility. Increasing enzyme supplementation resulted in both a quadratic and linear increase (P \u3c 0.001) in P and Ca utilization in experiment 1, however it only resulted in a linear increase (P \u3c 0.001) in Ca and P utilization in experiment 2. In experiment 1, there was a quadratic increase (P \u3c 0.01) in ileal digestibility of all the amino acids with increasing level of enzyme supplementation. In experiment 2, there was a quadratic increase (P \u3c 0.05) in ileal digestibility of Arg, His, and Val and nonessential amino acids (excluding Glu: P = 0.069 and Tyr: P = 0.088) and a linear increase (P = 0.001) in ileal digestibility of Thr when comparing the enzyme supplemented diets. There was a quadratic increase (P \u3c 0.05) with increasing levels of enzyme supplementation in bone breaking strength and bone ash in both studies. In conclusion, Allzyme® Spectrum supplementation improved growth performance, energy and nutrient digestibility and utilization, and bone mineralization in broiler chickens and reduced jejunal digesta viscosity in 21- and 22-day-old broiler chickens fed wheat-based diets

Influence of aluminum oxide on the prebiotic thermal synthesis of Gly-Glu-(Gly-Glu)(n) polymer

Artículo de publicación ISIThe effect of the aluminum oxide on the thermal synthesis of the glycine-glutamic acid (Gly-Glu-(Gly-Glu)(n) polymer is described. The thermal synthesis in the molten state was carried out in the absence and presence of the oxide. In both cases, the vibrational spectra showed characteristic group frequencies corresponding predominantly to a Gly-Glu-(Gly-Glu)(n) sequence in the polymeric structure. The theoretical spectral data support the experimental proposed Gly-Glu-(Gly-Glu)(n) sequence for the polymer. The SEM-EDX characterization of the solid phase involved in the thermal synthesis showed that the aluminum oxide participates as a site for nucleation and growth of the polymer, explaining the increase of 25% efficiency in the presence of aluminum oxide. Electrophoresis data show shorter polypeptide chains in the presence of aluminum oxide.Fondecyt 108512

Chemical Properties And Probiotics Survivability Of Symbiotic Coconut Yogurt Using Polymerized Whey Protein As A Gelation Agent

Food products from coconut fruits are delicious and nutritious; the coconut water could be directly used as a sports drink; whereas the meat can be processed to coconut milk, coconut puree and other products that are rich in medium fatty acids that can be burnt quickly to provide energy to the body. In recent years, products that incorporated the probiotics with coconut have been developed, however the texture and nutritional qualities were not satisfied. The purpose of the study was to create a functional coconut yogurt using polymerized whey protein (PWP) as a gelation agent to achieve a better mouthfeel and also increase the protein content of the final product. In the preliminary studies, different ratios of PWP/stabilizer system were tested to optimize the formulation. After the formula was finalized, three groups including control yogurt, PWP fortified yogurt and Ca/vitamin D fortified yogurt of 3 trials were made for further analysis. The chemical composition of the coconut yogurt including protein, fat, minerals, total solids and ash were analyzed. A sensory evaluation was also conducted to compare the lab samples from each group with the commercial samples. Result showed that there was no difference of yogurt properties within three lab groups except for the firmness. However, the lab groups had a significantly (P\u3c0.05) higher score for most properties than commercial group. pH values, viscosity and probiotics survivability were also analyzed weekly during the 8 weeks of storage. The pH significantly increased (P\u3c0.05) for all groups, whereas the viscosity showed a slow but significant decrease in all groups (P\u3c0.05) with the same decreasing rate (P\u3e0.05). At the last week of study, only Lactobacillus paracasei were above the therapeutic level in all three groups. Lactobacillus acidophilus did not reach that level at the first week of storage. The difference of survivability among three groups were all significant different (P\u3c0.05)

Functional ingredients from valorization of melon (Cucumis melo L.) by-products : production, bioactivity and potential application

Currently, fruit processing industries are responsible for the production and accumulation of large amounts of vegetable by-products, which are in some cases disposed of in landfills as waste, causing environmental and economic problems. Melon by-products are no exception and are part of this problem due to the proportion generated, which represents about 30% in residue (fresh weight), during its industrial processing. The development of an integral volorisation strategy for melon by-products through green and sustainable processes in the context of zero waste and circular bioeconomy is an important task. This will allow its full valorisation and reincorporation into the industrial value chain as a rich source of natural and bioactive ingredients, demonstrating the applicability of high economic value and reduced environmental impact. The main objective of this Ph D work was to fully explore and with zero¬waste the value of melon by-products and the development of functional ingredients rich in bioactive molecules with high added value, including different fractions rich in pigments, polyphenols, functional proteins (antifreeze and coagulating enzymes), pectin, microcellulose and a flour rich in fiber. In addition, it also allowed the development of an integrated downstream extractive process using clean technologies and the evaluation of the biological and technological properties of the obtained functional ingredients to establish their value and potential application. Initially, fresh melon peels were fractionated by mechanical processes within the zerowaste and biorefinery approaches, generating three fractions, which were characterized. I) The pellet fraction (PF), which represents the smallest fraction (2.0% of the total fresh weight of the peels (FW)), is the richest fraction in proteins (34.90% w/w), chlorophylls (174.84 mg/100 g FW) and total carotenoids (98.59 mg/100 dry matter (DM)) with βcarotene, lutein, β-cryptoxanthin and violaxanthin quantified as the main ones. This fraction has also been valorised through disruption processes combined with solid-liquid extraction methods to separate and isolate all important constituents, including proteins, chlorophylls and xanthophylls. II) The solid fraction (SF) represents 21.5% of the FW and is the richest fraction in fiber (44.42% w/w), which revealed the composition of cellulose, hemicellulose and lignin (27.67%, 8.2% and 26.5% w/w, respectively), showing great potential as an ingredient rich in antioxidant fiber. Associated with its bioactive compound profile, this fraction was also subjected to simulated conditions of the gastrointestinal tract (GIT) and subsequently evaluated by in vitro fecal fermentation with the objective to develop a prototype of functional flour for health promotion, mainly associated with its prebiotic potential. The results of the 16rRNA gene analysis showed that SF did not impact negatively the intestinal microbiota diversity and allowed the positive production of short-chain fatty acids (acetate > propionate > butyrate). In addition, the SF fraction also showed high pectin content, so in a second approach, it was also extracted by testing different acids combined with temperature, being citric acid the one that exhibited the best efficacy, allowing 34% w/w extraction yield and 60-70% methyl esterification, and showing good emulsifying and gelling properties. After extracting pectin from the SF fraction, the lignocellulosic residues from melon were subjected to extraction of microcrystalline cellulose (MCC) by two methods using NaOH: traditional and thermoalkaline. The results showed a higher degree of crystallinity by the thermoalkaline method than by the traditional process (51¬61% and 54-55%, respectively). Finally, III) the liquid fraction (LF), the most representative fraction in fresh weight with about 70% due to its high-water content (>90%). This fraction showed high antioxidant activity by the ABTS, DPPH and ORAC methods attributed to the high polyphenol content (798.43 mg GAE/100 g DM). The LF fraction was subjected to the conditions of the GIT. The total phenolic content (TPC) was maintained in the mouth and gastric phase (453.69 and 425.89 mg/100 g DM, respectively), while in the small intestine a drastic decrease was observed (reaching 313.37 mg/100 g DM), which corresponds to 54-57% of recovery index (RI), however, the antioxidant activity of ABTS and DPPH was still significant, which confirm the capacity of such compounds to exert their bioactive properties (54-76% accessibility index (ACI)). On the other hand, this fraction had a prebiotic effect (2% w/v) on the main beneficial groups of the intestinal microbiota, the Lactobacillus sp. and Bifidobacterium sp., modulating positively its growth and metabolism. Furthermore, cucumisin (CUC) was extracted through a green chemistry approach using carrageenan as a precipitating agent, proving to be an effective strategy to isolate it with a yield of 0.17 g CUC/100 g of by-products, and with better purification factor of proteolytic activity than the traditional precipitation process (17.65 and 1.60¬ folds, respectively), maintaining its biological properties. The melon proteins extracted by this green precipitation process also exhibited antifreeze properties, possibly attributed to the great similarity in structure and molecular weights (6.2 and 3.5 kDa) with other proteins previously reported such as type III antifreeze proteins (C-terminal domain, few alanine residues and no cysteine residues) and type I (alanine-rich), respectively. Briefly, the results of this work on the integral valorization of melon peels will contribute to a sustainable development in the fruit processing industries, allowing the obtention of new functional ingredients/additives through clean strategies and preserving their bioactivity and functionality.Atualmente, as indústrias de processamento de frutas são responsáveis pela produção e acumulação de grandes quantidades de subprodutos vegetais, os quais são em alguns casos descartados em aterros como resíduos, causando problemas ambientais e económicos. Os subprodutos do melão não são uma exceção e fazem parte deste problema devido à proporção gerada que representa cerca de 30% em resíduo (peso fresco), durante o seu processamento industrial. O desenvolvimento de uma estratégia de valorização integral para os subprodutos do melão através de processos verdes e sustentáveis no contexto de resíduos zero e bioeconomia circular é uma tarefa importante. Isto permitirá a sua valorização total e reincorporação na cadeia de valor industrial como uma fonte rica em ingredientes naturais e bioativos, demonstrando aplicabilidade de elevado valor económico e redução do impacto ambiental. O objetivo principal deste trabalho de doutoramento foi explorar de forma integral e com resíduo zero o valor dos subprodutos de melão e o desenvolvimento de ingredientes funcionais ricos em moléculas bioativas e de alto valor agregado, incluindo diferentes frações ricas em pigmentos, polifenóis, proteínas funcionais (anticongelantes e enzimas coagulantes), pectina, microcelulose e uma farinha rica em fibra. Além disso, permitiu igualmente desenvolver um processo extrativo integrado em cascata utilizando tenologias limpas e avaliar as propriedades biológicas e tecnológicas dos ingredientes funcionais obtidos para estabelecer o seu valor e potencial aplicação. Inicialmente, cascas frescas de melão foram fracionadas por processos mecânicos dentro das abordagens de resíduo zero e biorefinaria, gerando três frações, que foram caracterizadas. I) A fração do precipitado (PF), que representa a menor fração (2,0% do peso fresco total da casca (FW)), é a fração mais rica em proteínas (34,90% w/w), clorofilas (174,84 mg/100 g FW) e carotenoides totais (98,59 mg/100 DM), com o β-caroteno, luteína, βcriptoxantina e violaxantina quantificados como principais. Essa fração também foi valorizada através de processos de rutura combinados com métodos de extração sólidolíquido para separar e isolar todos os constituintes importantes, incluindo proteínas, clorofilas e xantofilas. II) A fração sólida (SF) representa 21,5% do FW e é a fração mais rica de fibra (44,42% p/p), a qual revelou a composição de celulose, hemicelulose e lenhina (27,67%, 8,2% e 26,5% p/p, respetivamente) apresentando grande potencial como ingrediente rico em fibra antioxidante. Associado ao seu perfil de compostos bioativos, esta fração também foi submetida a condições simuladas do trato gastrointestinal (TGI) e posteriormente avaliada por fermentação fecal in vitro com o objetivo de desenvolver um protótipo de farinha funcional para promoção da saúde, principalmente associado ao seu potencial prebiótico. Os resultados da análise do gene 16rRNA mostraram que o SF não impactou negativamente a diversidade da microbiota intestinal e permitiu a produção positiva de ácidos gordos de cadeia curta (acetato> propionato> butirato). Além disso, a fração SF também mostrou elevado teor em pectina, pelo que em uma segunda abordagem esta também foi extraída testando diferentes ácidos combinados com temperatura, sendo o ácido cítrico aquele que exibiu melhor eficácia, permitindo 34% w/w de rendimento de extração e 60-70% de esterificação metílica, e apresentando boas propriedades emulsificantes e gelificantes. Após a extração da pectina da fração SF, os resíduos lenhocelulósicos do melão foram submetidos a extração da celulose microcristalina (MCC) por dois métodos utilizando NaOH: o tradicional e termoalcalino. Os resultados mostraram maior grau de cristalinidade pelo método termoalcalino do que pelo processo tradicional (51-61% e 54¬ 55%, respetivamente). Finalmente, III) a fração líquida (LF), a fração mais representativa em peso fresco com cerca de 70% pelo seu elevado conteúdo em água (>90%). Esta fração mostrou uma elevada atividade antioxidante pelos métodos ABTS, DPPH e ORAC atribuídos ao alto teor de polifenóis (798,43 mg GAE/100 g MS). A fração LF foi submetido às condições do TGI. O conteúdo fenólico total (CFT) foi mantido na boca e fase gástrica (453,69 e 425,89 mg/100 g de MS, respetivamente), enquanto no intestino delgado foi observada uma diminuição drástica (atingindo 313,37 mg/100 g de MS) que corresponde a 54-57% de índice de recuperação (IR), no entanto a atividade antioxidante de ABTS e DPPH ainda foi significativa, que confirmam a capacidade de tais compostos exercerem as suas propriedades bioativas (54-76% índice de acessibilidade (IAC)). Por outro lado, esta fração apresentou efeito prebiótico (2% p/v) sobre os principais grupos benéficos da microbiota intestinal, os Lactobacillus sp. e Bifidobacterium sp., modulando o seu crescimento e o metabolismo positivamente. Além disso, a cucumisina (CUC), foi extraída através de uma abordagem de química verde usando carragenina como agente precipitante, mostrando ser uma estratégia eficaz para isolá¬la com um rendimento de 0,17 g CUC/100 g de sub-produtos, e mostrando melhor grau de purificação e atividade proteolítica do que o processo de precipitação tradicional (17,65 e 1,60 vezes, respetivamente), mantendo as suas propriedades biológicas. As proteínas do melão extraídas por este processo de precipitação verde também exibiram propriedades anticongelantes, possivelmente atribuídas à grande semelhança na estrutura e pesos moleculares (6,2 e 3,5 kDa) com outras proteínas anticongelantes já relatados do tipo III (domínio C-terminal, poucos resíduos de alanina e nenhum resíduo de cisteína) e do tipo I (ricos em alanina), respetivamente. Resumidamente, os resultados deste trabalho de valorização integral de cascas de melão contribuirão para um desenvolvimento sustentável nas indústrias de processamento de frutas, permitindo obtenção de novos ingredientes/aditivos funcionais por meio de estratégias limpas e com preservação da sua bioatividade e funcionalidade