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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.
51

Βιοτεχνολογικές μέθοδοι επεξεργασίας υγρών αποβλήτων ελαιοτριβείου / Biotechnological methods for olive mill wastewater treatment

Μπλίκα, Παρασκευή 14 September 2010 (has links)
Τα υγρά απόβλητα ελαιοτριβείου (ΥΑΕ) παράγονται κατά την εξαγωγή του ελαιόλαδου από τα παραδοσιακά και τα φυγοκεντρικά ελαιοτριβεία τριών φάσεων. Τα ΥΑΕ έχουν διαφορετικά χαρακτηριστικά τα οποία εξαρτώνται από τη διαδικασία παραγωγής και τον τύπο των ελιών που χρησιμοποιούνται. Τα περισσότερα ελαιοτριβεία στην Ελλάδα χρησιμοποιούν την τριφασική διαδικασία εξαγωγής του ελαιόλαδου. Παρόλα αυτά, κάποια καινούρια χρησιμοποιούν τη διφασική διαδικασία εξαγωγής του ελαιολάδου. Παραδοσιακά ελαιοτριβεία συνεχίζουν να υπάρχουν, αλλά σε μικρότερη έκταση. Τα ΥΑΕ αποτελούν ένα σημαντικό πρόβλημα για την περιοχή της Μεσογείου, όπου παράγεται το 95 % της παγκόσμιας παραγωγής ελαιολάδου, εξαιτίας της υψηλής τους συγκέντρωσης σε χημικά απαιτούμενο οξυγόνο (ΧΑΟ) και της ικανότητάς τους να αντιστέκονται στη βιοαποδόμηση εξαιτίας της υψηλής τους περιεκτικότητας σε φαινολικές ενώσεις. Αυτές οι ενώσεις οφείλονται για το μαύρο χρώμα και τις φυτοτοξικές και αντιβακτηριδιακές ιδιότητες των ΥΑΕ. Διάφορες φυσικοχημικές μέθοδοι έχουν προταθεί για την επεξεργασία των ΥΑΕ, συμπεριλαμβανομένων της απλής συμπύκνωσης, της επίπλευσης και καθίζησης, της εξάτμισης και της χρήσης επιλεγμένων μεμβρανών, της ουδετεροποίησης με την προσθήκη H2SO4, της οξείδωσης με O3 και αντιδραστήριο Fenton, καθώς επίσης και την επαναχρησιμοποίηση των ΥΑΕ με διασκορπισμό σε αγροτικά εδάφη σαν λίπασμα. Σε ότι αφορά τις βιολογικές μεθόδους, οι αναερόβιες βιολογικές διεργασίες είναι ιδιαίτερα αποδοτικές εξαιτίας των γνωστών πλεονεκτημάτων που εμφανίζουν και σχετίζονται με την εξοικονόμηση ενέργειας και χημικών και της μικρής παραγωγής λάσπης, ειδικότερα όταν αφορά την επεξεργασία αποβλήτων με υψηλή συγκέντρωση ΧΑΟ. Η εποχιακή λειτουργία των ελαιοτριβείων (Νοέμβριος – Φεβρουάριος) δεν αποτελεί μειονέκτημα για τις αναερόβιες διεργασίες εξαιτίας των χαμηλών παρατηρούμενων ρυθμών αποδόμησης των μεθανογόνων μικροοργανισμών και της εύκολης επαναλειτουργίας των αναερόβιων χωνευτήρων μετά από αρκετούς μήνες μη λειτουργίας. Παρόλο που η αναερόβια χώνευση χρησιμοποιείται κατά κύριο λόγο για τη μείωση του υψηλού οργανικού φορτίου των ΥΑΕ, η παρουσία ενώσεων στα ΥΑΕ τοξικών προς τους μεθανογόνους φαίνεται να είναι ένα σημαντικό πρόβλημα για την αναερόβια επεξεργασία των ΥΑΕ. Μία προσέγγιση στο πρόβλημα θα ήταν η αραίωση του αποβλήτου ώστε να μειωθεί η συγκέντρωση των φαινολικών ενώσεων και των λιπαρών οξέων. Σε αυτή την περίπτωση εξετάζεται και η απομάκρυνση των στερών του αποβλήτου πριν την αναερόβια χώνευση. Μία δεύτερη προσέγγιση θα ήταν η εφαρμογή αερόβιας προεπεξεργασίας του αποβλήτου ώστε να απομακρυνθούν ενώσεις που είναι τοξικές για τα μεθανογόνα βακτήρια. Πιο συγκεκριμένα, ένα πρώτο στάδιο αερόβιας προεπεξεργασίας του ΥΑΕ με μύκητα λευκής σήψης, έχει προταθεί ως η πιο κατάλληλη μικροβιακή διεργασία προεπεξεργασίας για την επιλεκτική απομάκρυνση των φαινολικών. Στόχος της παρούσας διατριβής ήταν να μελετηθεί η ικανότητα του μύκητα λευκής σήψης Pleurotus ostreatus κάτω από άσηπτες ή μη συνθήκες να λειτουργήσει σε έναν καινοτόμο βιοαντιδραστήρα καθοδικής ροής και να διευρενηθεί η αποδοτικότητα εναλλακτικά της αραίωσης ή/και της προεπεξεργασίας στην αναερόβια χώνευση ΥΑΕ σε αναδευόμενο μεσόφιλο αντιδραστήρα. Επίσης, μελετήθηκε η αναερόβια χώνευση ΥΑΕ σε αντιδραστήρα τύπου ASBR και αντιδραστήρα PABR, αντίστοιχα. Μία καινοτόμος μέθοδος ακινητοποίησης των μυκήτων αποδείχτηκε κατάλληλη για την ανάπτυξη μιας αποδοτικής διεργασίας προεπεξεργασίας για την απομάκρυνση των φαινολικών. Η αναερόβια χώνευση είναι η πιο αποδοτική διεργασία για την επεξεργασία υγρών αποβλήτων ελαιοτριβείου. Παρόλα αυτά, αραίωση ή/και κάποιου τύπου προεπεξεργασία είναι απαραίτητη για την αποφυγή τοξικότητας των φαινολικών στους μεθανογόνους. Θερμική προεπεξεργασία ακολουθούμενη από καθίζηση ώστε να απομακρυνθεί το στερεό περιεχόμενο, από την άλλη, αποδείχτηκε ένας μη επιθυμητός τρόπος προεπεξεργασίας. Επιπλέον, αραιωμένο ΥΑΕ 1:1, χωρίς την απομάκρυνση των στερεών μπορεί να υποστεί επεξεργασία αποδοτικά σε υδραυλικό χρόνο παραμονής 30 ημέρες, εξασφαλίζοντας σταθερή παραγωγή βιοαερίου. Βιολογική προεπεξεργασία με μύκητα μπορεί να οδηγήσει σε σταθερή διεργασία σε υδραυλικό χρόνο παραμονής 30 ημέρες. Η αναερόβια επεξεργασία του αποβλήτου σε αντιδραστήρα ASBR είναι εφικτή με ισοδύναμο χρόνο παραμονής 30 ημερών χωρίς να αραιωθεί το απόβλητο. Η επεξεργασία σε αντιδραστήρα PABR είναι ωστόσο πιο αποδοτική εξαιτίας του σχεδόν κατά μία τάξη μεγέθους μικρότερο υδραυλικού χρόνου παραμονής (3.75 ημέρες), που αυτός μπορεί να λειτουργήσει και της μεγαλύτερης απόδοσης του σε βιοαέριο. Το αναερόβια επεξεργασμένο απόβλητο μπορεί να καταστεί κατάλληλο για διάθεση μετά από κατάλληλη επεξεργασία μεμβρανών (συνδυασμός υπερδιήθησης και αντίστροφης όσμωσης). / Olive mill wastewater (OMW) is produced during the extraction of oil from the olive fruit by the traditional mill and press process. ΟΜW has a wide range of characteristics depending on the type of the mill and the type of olive and equipment employed. Most of the mills in Greece use a 3-phase extraction process. However, some of the newer ones use the 2-phase extraction process. Traditional mills are still present but to a limited extent. OΜW treatment and disposal has become a critical environmental problem in the Mediterranean area that accounts for approximately 95% of the world olive oil production. This is because of its high organic chemical oxygen demand (COD) concentration, and because of its resistance to biodegradation due to its high content in phenolic compounds. These compounds are responsible for its dark color, and its phytotoxic and antibacterial properties. Various physico-chemical methods have been proposed for treating OMW, including simple evaporation, flotation and settling, vaporization and use of selected membranes, neutralization with addition of H2SO4, oxidation by O3 and Fenton reagent, as well as reuse of the OMW by spreading onto agricultural soil as an organic fertilizer. As far as biological processes are concerned, anaerobic biological processes are particularly suitable because of their well known advantages related to energy and chemicals saving and to the low production of sludge, especially when it comes to treatment of high COD wastewaters. The seasonal nature of the operation of olive mills (typically November to February) is not a disadvantage for anaerobic processes because the observed decay rates for methanogens are very low and a digester can be easily restarted following several months of shut-down. Although anaerobic digestion may be in principle used for reducing the high organic content of OMW, the presence of compounds toxic to methanogens in OMW appears to be a significant problem for the anaerobic digestion of OMW. One approach to the problem has been to sufficiently dilute the OMW to reduce the concentration of phenolics and fatty acids. In this case, the possibility of prior solids removal needs to be examined. A second approach has been the use of aerobic pretreatment of OMW to remove compounds that are toxic to methanogenic consortia. In particular, a preceding aerobic treatment of OMW with white-rot fungi, has been proposed as the most suitable microbial pretreatment process for the selective removal of phenolics. The aim of the present study was to study the ability of the white rot fungus Pleurotus ostreatus under aseptic or non aseptic conditions to function in a novel trickling filter immobilized fungi bioreactor and to investigate the feasibility of alternative dilution and/or pretreatment processes for the anaerobic digestion of olive-mill wastewater in a stirred tank mesophilic digester. The anaerobic digestion of OMW in an anaerobic sequencing batch reactor (ASBR) and in a periodic anaerobic baffled reactor (PABR) was also studied. A novel fungi immobilization method proved very suitable for the development of an efficient pretreatment process for phenolics removal. Anaerobic digestion is the most effective process for the treatment of olive mill wastewater. However, dilution and/or some type of pretreatment are necessary to avoid toxicity of the phenolics on the methanogens. Thermal pretreatment followed by sedimentation to remove the solids content, on the other hand proved to be an undesirable type of pretreatment. Diluted 1:1 raw OMW on the other hand, without any solids removal, can be effectively treated at an HRT of 30d, securing a stable high biogas yielding operation. Biological pre-treatment with fungi may lead to a stable process at an HRT of 30d. Anaerobic digestion of OMW using an ASBR (anaerobic sequencing batch reactor) is feasible at an equivalent HRT of 30d with the advantage that it can treat nondiluted wastewater. Treatment in a PABR, however, is much more effective as it requires an order-of –magnitude lower HRT ( 3.75 d) and yields large amounts of biogas. The anaerobically treated effluent is still not suitable for disposal. A membrane process such as reverse osmosis may be effectively used to render the anaerobically treated wastewater readily disposable.
52

Biodegradace polychlorovaných bifenylů pomocí ligninolytických hub a jejich enzymů / Biodegradation of polychlorinated biphenyls by white - rot fungi and their enzymes

Linhartová, Lucie January 2010 (has links)
Polychlorinated biphenyls (PCB) represent relevant persistent organopollutants of the environment and the estimated amount of PCB released into the environment is 750000 metric tons. White-rot fungi have been studied for long time due to their degradative potential toward various aromatic pollutants and it is known that these fungi are able to decompose PCB in vivo. Biodegradation of PCB by the fungus Pleurotus ostreatus was studied in the frame of this work. A high degradative efficiency of P. ostreatus was observed in the first set of experiments, even in the presence of relative high amount of added PCB. Fungus was able to transform 780±50 µg out of the intial amount 1000 µg in 20 ml of a cultivation media within 42 days. A decrease in toxicity was recorded during the degradation that suggests the suitability of this organism for a practical use in decontamination. In vitro experiments with purified laccase induced with Cu2+ from this fungus did not prove any participation of the enzyme in the first step of PCB transformation. The enzyme did not show an ability to degrade PCB even after purification from cultivation media containing PCB. It was found that the first step of PCB transformation can be performed by an intracellular process with microsomal fraction. A degradation of 44-67% was observed for...
53

Studium metabolismu 17 α-ethinylestradiolu cytochromy P450 / Study of the metabolism of 17α-ethinylestradiol by cytochromes P450

Valášková, Petra January 2014 (has links)
A synthetic estrogen 17α-ethinylestradiol (EE2) is the main active component of the hormonal contraceptive pills. The rise of consumption of hormonal contraceptives has increased the risk of the back negative effects of EE2 to aquatic organisms. EE2 belongs to the endocrine disruptive compounds known for mimicking natural hormones. A more detailed examination of the transformation of this compound in vivo and in vitro can contribute to a better understanding of its negative effects. This master thesis is therefore devoted to the study of the metabolism of EE2 in two selected model organisms. The ligninolytic fungus Pleurotus ostreatus is the type of fungi with promising biodegradation ability to a lot of pollutants. These properties have led to numerous studies of the degradation potential of P. ostreatus towards EE2, with the possibility of removing this compound from the environment. EE2 has been degraded by the fungus P. ostreatus in vivo resulting in one hydroxylated metabolite, which estrogenic activity is in need for further study. In vitro studies were carried out with a microsomal fraction isolated from the mycelium of this fungus. The conversion of EE2 in vitro via CYPs dependent on NADPH has not been demonstrated, however using KHP as a cofactor, there was one metabolite of EE2 found,...
54

Studium interakce houby Pleurotus ostreatus a bakteriálních kultur na abiotickém nosiči - morfologická, biochemická a proteomická analýza / Study of the interaction between fungus Pleurotus ostreatus and bacterial cultures on the abiotic surfaces - morphological, biochemical and proteomic analysis

Kozická, Barbora January 2015 (has links)
Ligninolytic fungi are well known for their ability to degrade a wide range of xenobiotics contaminating the environment, including synthetic industrial dyes. In this work Pleurotus ostreatus was used for decolorization of a synthetic textile dye Remazol Brilliant Blue R (RBBR). To set up a model fungal "fixed-bed" bioreactor the fungus was immobilized on a polyurethane foam and artificially contaminated with a model bacterium Rhodococcus erythropolis. The development of bacterial contamination can be expected during a real application of fungal bio filters in wastewater treatment. The main aim of the work was to study interspecies interactions in the model bioreactors during the dye decolorization. Ligninolytic enzyme activities were followed in the bioreactor cultures as markers of fungal biodegradation ability. In contrast to the controls, no bacterial growth was observed in the P. ostreatus bioreactor culture liquid. The results showed that fungal laccase, pH of the culture liquid, and glucose consumption by the fungus had no effect on the bacterial growth. However, 4*105 - 1,3*106 CFU/ml of R. erythropolis was detected to be associated with the fungal solid support. The presence of these bacteria had no effect on the decolorization performance of the bioreactors. Dye decolorization efficiency...
55

Enzymatic Preparation of 2,5-Furandicarboxylic Acid (FDCA)—A Substitute of Terephthalic Acid—By the Joined Action of Three Fungal Enzymes

Karich, Alexander, Kleeberg, Sebastian B., Ullrich, René, Hofrichter, Martin 25 April 2018 (has links)
Enzymatic oxidation of 5-hydroxymethylfurfural (HMF) and its oxidized derivatives was studied using three fungal enzymes: wild-type aryl alcohol oxidase (AAO) from three fungal species, wild-type peroxygenase from Agrocybe aegerita (AaeUPO), and recombinant galactose oxidase (GAO). The effect of pH on different reaction steps was evaluated and apparent kinetic data (Michaelis-Menten constants, turnover numbers, specific constants) were calculated for different enzyme-substrate ratios and enzyme combinations. Finally, the target product, 2,5-furandicarboxylic acid (FDCA), was prepared in a multi-enzyme cascade reaction combining three fungal oxidoreductases at micro-scale. Furthermore, an oxidase-like reaction is proposed for heme-containing peroxidases, such as UPO, horseradish peroxidase, or catalase, causing the conversion of 5-formyl-2-furancarboxylic acid into FDCA in the absence of exogenous hydrogen peroxide.
56

Desarrollo y caracterización de nuevas harinas de lenteja y quinoa fermentadas con Pleurotus ostreatus

Sánchez García, Janaina 15 January 2024 (has links)
Tesis por compendio / [ES] La población mundial está en constante crecimiento, por lo que la soberanía alimentaria se ha convertido en un desafío crucial. Se estima que la demanda de alimentos de origen animal aumentará en un 68% para el año 2050, lo cual resulta insostenible a nivel medioambiental. Así, impulsar un mayor consumo de proteína vegetal se plantea como una de las estrategias dirigidas a promover la sostenibilidad ambiental, asegurando la disponibilidad de proteína dietética para toda la población. Si bien ciertas las legumbres y pseudocereales son una excelente fuente de nutrientes y en particular de proteína, también contienen ciertos antinutrientes que pueden limitar su digestibilidad. Este aspecto es especialmente relevante en aquellos grupos poblaciones con alteraciones gastrointestinales, como las que pueden aparecer con la edad en población sénior. En este contexto, el objetivo general de esta tesis doctoral es aplicar la fermentación en estado sólido (FES) como bioestrategia para la obtención de harinas de lenteja y quinoa con digestibilidad y bioaccesibilidad mejoradas. Para alcanzar este objetivo, se llevó a cabo la fermentación con el hongo Pleurotus ostreatus, en dos variedades de lentejas y quinoa, y se estabilizaron posteriormente mediante secado por aire caliente a diferentes temperaturas, además de la liofilización como método de referencia. Posteriormente, las harinas fermentadas fueron digeridas in vitro simulando el proceso digestivo de un adulto sano (estándar de referencia), así como en condiciones alteradas del adulto mayor. Los resultados obtenidos evidenciaron un incremento de proteína total, así como de la actividad inhibidora de la enzima convertidora de angiotensina (ECA), conjuntamente con una disminución del contenido en ácido fítico, todo ello como resultado de la actividad metabólica del hongo sobre el sustrato. A pesar de que la FES también ocasionó una reducción de la actividad antioxidante, el posterior secado por aire caliente, especialmente a 70 °C incrementó este parámetro. Asimismo, la FES y el secado por aire caliente promovieron cambios en el perfil fenólico, disminuyendo algunos compuestos e incrementando otros como el ácido gálico hasta 5 veces su contenido inicial. En cuanto al perfil volátil de las harinas fermentadas, este se caracterizó por un aroma dulce, afrutado y con matices a cacao, acompañado de notas de setas y sustratos cocidos, debido a las concentraciones de benzaldehído, hexanal, nonanal, furfural y 1-octen-3-ol que se generaron durante la fermentación. Por otro lado, con respecto a la digestibilidad de las harinas fermentadas en condiciones estándar de adulto sano, la FES y el secado a 70 °C incrementó la hidrólisis de las proteínas, así como la liberación de aminoácidos hidrófobos y aminoácidos cargados negativamente. La FES también disminuyó la actividad inhibidora de la ECA en los digeridos, sin embargo, ésta aumentó después del secado a 70 °C debido a las melanoidinas generadas durante el secado. Además, las propiedades antioxidantes y la bioaccesibilidad de minerales también se vieron incrementados con la FES y el posterior secado a 70 °C. Finalmente, la simulación de las alteraciones gastrointestinales que comúnmente se dan en el adulto mayor, indicaron que estas impactaban negativamente en la mayoría de los parámetros evaluados, a excepción de la bioaccesibilidad del magnesio, hierro y calcio en comparación con el modelo estándar. En conclusión, se ha logrado mejorar el perfil nutricional y funcional de las nuevas harinas obtenidas por fermentación con el hongo P. ostreatus, y posterior secado por aire caliente en comparación con las harinas obtenidas a partir de sustrato no fermentado, conduciendo esto a una mejora significativa en la digestibilidad y la bioaccesibilidad de los nutrientes, lo que puede ser especialmente relevante para el diseño de alimentos orientados a grupos de población con alta demanda de proteína de fácil digestión. / [CA] La població mundial està en constant creixement, per la qual cosa la sobirania alimentària ha esdevingut un desafiament crucial. S'estima que la demanda d'aliments d'origen animal augmentarà un 68% per a l'any 2050, cosa que resulta insostenible a nivell mediambiental. Així, impulsar un consum més gran de proteïna vegetal es planteja com una de les estratègies dirigides a promoure la sostenibilitat ambiental, assegurant la disponibilitat de proteïna dietètica per a tota la població. Si bé certs els llegums i pseudocereals són una excel·lent font de nutrients i en particular de proteïna, també contenen certs antinutrients que poden limitar-ne la digestibilitat. Aquest aspecte és especialment rellevant en aquells grups de poblacions amb alteracions gastrointestinals, com les que poden aparèixer amb l'edat en població sènior. En aquest context, l'objectiu general d'aquesta tesi doctoral és aplicar la fermentació en estat sòlid (FES) com a bioestratègia per obtenir farines de llentia i quinoa amb digestibilitat i bioaccessibilitat millorades. Per assolir aquest objectiu, es va dur a terme la fermentació amb el fong Pleurotus ostreatus, en dues varietats de llenties i quinoa, i es van estabilitzar posteriorment mitjançant assecat per aire calent a diferents temperatures, a més de la liofilització com a mètode de referència. Posteriorment, les farines fermentades van ser digerides in vitro simulant el procés digestiu d'un adult sa (estàndard de referència), així com en condicions alterades de l'adult més gran. Els resultats obtinguts van evidenciar un increment de proteïna total, així com de l'activitat inhibidora de l'enzim convertidor d'angiotensina (ECA), conjuntament amb una disminució del contingut en àcid fític, com a resultat de l'activitat metabòlica del fong sobre el substrat. Tot i que la FES també va ocasionar una reducció de l'activitat antioxidant, el posterior assecat per aire calent, especialment a 70 °C va incrementar aquest paràmetre. Així mateix, la FES i l'assecatge per aire calent van promoure canvis en el perfil fenòlic, disminuint alguns compostos i incrementant-ne d'altres com l'àcid gàlic fins a 5 vegades el contingut inicial. Quant al perfil volàtil de les farines fermentades, aquest es va caracteritzar per una aroma dolça, afruitada i amb matisos a cacau, acompanyat de notes de bolets i substrats cuits, a causa de les concentracions de benzaldehid, hexanal, nonanal, furfural i 1-octen -3-ol que es van generar durant la fermentació. D'altra banda, pel que fa a la digestibilitat de les farines fermentades en condicions estàndard d'adult sa, la FES i l'assecatge a 70 °C va incrementar la hidròlisi de les proteïnes, així com l'alliberament d'aminoàcids hidròfobs i aminoàcids carregats negativament. La FES també va disminuir l'activitat inhibidora de l'ACA en els digerits, però aquesta va augmentar després de l'assecat a 70 °C a causa de les melanoïdines generades durant l'assecat. A més, les propietats antioxidants i la bioaccessibilitat de minerals també es van veure incrementats amb la FES i el posterior assecat a 70 °C. Finalment, la simulació de les alteracions gastrointestinals que comunament es donen a l'adult major, van indicar que aquestes impactaven negativament a la majoria dels paràmetres avaluats, a excepció de la bioaccessibilitat del magnesi, ferro i calci en comparació del model estàndard. En conclusió, s'ha aconseguit millorar el perfil nutricional i funcional de les noves farines obtingudes per fermentació amb el fong P. ostreatus, i posterior assecat per aire calent en comparació amb les farines obtingudes a partir de substrat no fermentat, conduint-ho a una millora significativa en la digestibilitat i la bioaccessibilitat dels nutrients, cosa que pot ser especialment rellevant per al disseny d'aliments orientats a grups de població amb alta demanda de proteïna de fàcil digestió. / [EN] The world's population is constantly growing, making food sovereignty a crucial challenge. It is estimated that the demand for animal-based food will increase by 68% by 2050, which is environmentally unsustainable. Thus, encouraging greater consumption of plant protein is one of the strategies aimed to promote environmental sustainability by ensuring the availability of dietary protein for the entire population. Although certain legumes and pseudocereals are an excellent source of nutrients and in particular protein, they also contain certain anti-nutrients that can limit their digestibility. This aspect is especially relevant in those population groups with gastrointestinal disorders, such as those that may appear with age in the elderly population. In this context, the general objective of this doctoral thesis is to apply solid-state fermentation (SSF) as a biostrategy to obtain lentil and quinoa flours with improved digestibility and bioaccessibility. To achieve this objective, fermentation with the fungus Pleurotus ostreatus was carried out on two varieties of lentils and quinoa, and subsequently stabilised by hot air drying at different temperatures, in addition by freeze-drying as a reference method. Subsequently, the fermented flours were digested in vitro simulating the digestive process of a healthy adult (reference standard), as well as under altered conditions of the elderly. The results obtained evidenced an increase in total protein, as well as in angiotensin-converting enzyme (ACE) inhibitory activity, together with a decrease in phytic acid content, all as a result of the metabolic activity of the fungus on the substrate. Although SSF also caused a reduction in antioxidant activity, subsequent hot air drying, especially at 70 °C, increased this parameter. Similarly, SSF and hot air-drying promoted changes in the phenolic profile, decreasing some compounds and increasing others such as gallic acid up to 5 times its initial content. The volatile profile of the fermented flours was characterised by a sweet, fruity aroma with hints of cocoa, accompanied by notes of mushrooms and cooked substrates, due to the concentrations of benzaldehyde, hexanal, nonanal, furfural and 1-octen-3-ol that were generated during fermentation. On the other hand, regarding the digestibility of the fermented flours under standard healthy adult conditions, SSF and drying at 70 °C increased the hydrolysis of proteins, as well as the release of hydrophobic and negatively charged amino acids. SSF also decreased the ACE inhibitory activity of the digests, however, it increased after drying at 70 °C due to melanoidins generated during drying. Furthermore, antioxidant properties and mineral bioaccessibility were also increased with SSF and subsequent drying at 70 °C. Finally, simulation of gastrointestinal disturbances commonly found in the older adult indicated that these impacted negatively on most of the parameters evaluated, with the exception of the bioaccessibility of magnesium, iron and calcium compared to the standard model. In conclusion, the nutritional and functional profile of the new flours obtained by fermentation with the fungus P. ostreatus, and subsequent hot air drying has been improved compared to flours obtained from unfermented substrate, leading to a significant improvement in the digestibility and bioaccessibility of nutrients, which may be particularly relevant for the design of foods oriented to population groups with a high demand of easily digestible protein. / Sánchez García, J. (2023). Desarrollo y caracterización de nuevas harinas de lenteja y quinoa fermentadas con Pleurotus ostreatus [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/202014 / Compendio
57

Hydrophobins in wood biology and biotechnology / Hydrophobinen in Holz Biologie und Biotechnologie

Peddireddi, Sudhakar 28 March 2008 (has links)
No description available.
58

Actions of lignocellulolytic enzymes on Abies grandis(grand fir) wood for application in biofuel production

Cherdchim, Banyat 27 October 2010 (has links)
No description available.

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