Silk is a fiber of protein nature, of animal origin, which is extracted from cocoons of spiders of the class of Arachnida and from Lepidoptera such as mites, butterflies and moths. It consists essentially of two structural filaments of fibroin, a "core" protein, coated with sericin, a "glue" protein. Of the two proteins only the fibroin is part of the production process: the sericin must be removed from the fibroin so that the fiber acquires shine, softness, smoothness, whiteness and dyeability. Sericin, as a waste obtained from industrial processes in the textile sector, is present in the effluents of silk processing, generating an environmental problem of water pollution. Despite being considered a waste material in the textile industry, sericin is a biologically active protein that has attracted the interest of the scientific community for its potential use in the pharmaceutical field. In accordance with the waste valorisation process and the rules of environmental sustainability of the circular economy, recovering the sericin from wastewater would give two significant advantages: a lower environmental impact and the attainment of a precious raw material with high added value, intended for application in the most diverse sectors, particularly in the production of cosmetic products and in dermatology. The purpose of the thesis is to evaluate the antioxidant, antityrosinase and antielastase biological properties of sericins obtained with two different processes. In particular, the sericin extracted from Bombyx mori coocon was considered, using ad-hoc processes developed in research laboratories, and sericin isolated from the wastewater of the textile industry. The sericins thus obtained were then subjected to three different preservation treatments: lyophilization, spray drying or sterilization. The results obtained demonstrate how the sericins from both sources show antioxidant activity, which, however, appears to be much higher in the case of samples obtained through the degumming process in the laboratory, compared to the sericins recovered from wastewater. In relation to the type of conservation treatment, drying, both by freeze-drying and spray-drying, is the most suitable method for maintaining ROS-scavenging activity. The analysis of the anti-thyrosinase activity of the sericin recovered from the wastewater subjected to the subsequent lyophilization shows promising results: the samples show a greater activity, albeit slightly, compared to the samples of sericin obtained by degumming in the laboratory subjected to the same treatment. The sericines subjected to spray drying or sterilization, regardless of the source, show, in fact, significantly lower levels. All sericin groups show inhibitory activity against the enzyme elastase. Also in this case the sericin extracted from the wastewater of the textile industry shows a similar activity to the samples obtained by degumming methods in the laboratory. In particular, the most promising results were obtained by testing samples of sericin from wastewater subsequently subjected to spray drying, which showed the greatest antielastase properties. In conclusion, the sericin recovered from wastewater has good antitirosinase, antielestase and antioxidant properties and therefore it can be used as a bioactive component of products for dermatological and cosmetic use and therefore destined to a revaluation process, according to a planned economic system to be able to reuse in subsequent production cycles.
La seta è una fibra di natura proteica, di origine animale, che si estrae da bozzoli di ragni della classe degli Arachnida e da Lepidotteri quali acari, farfalle e tarme. È costituita essenzialmente da due filamenti strutturali di fibroina, proteina core, rivestiti da sericina, proteina colla. Delle due proteine solo la fibroina rientra nei processi di produzione: la sericina deve essere rimossa dalla fibroina affinché la fibra acquisisca lucentezza, morbidezza, levigatezza, bianchezza e tingibilità. La sericina, quale scarto ottenuto dai processi industriali in ambito tessile, è presente negli effluenti della lavorazione della seta, generando un problema di carattere ambientale di inquinamento delle acque. Nonostante venga considerata materiale di scarto nellindustria tessile, la sericina è una proteina biologicamente attiva che ha attirato linteresse della comunità scientifica per un suo potenziale utilizzo in ambito farmaceutico. In accordo con il processo di valorizzazione dei rifiuti e alle regole di sostenibilità ambientale delleconomia circolare, recuperare la sericina dalle acque reflue conferirebbe due notevoli vantaggi: un minor impatto ambientale e lottenimento di una materia prima preziosa, ad alto valore aggiunto, destinata allapplicazione nei più disparati settori, in particolare nella produzione di prodotti cosmetici e nella dermatologia. Lo scopo della tesi è quello di valutare le proprietà biologiche antiossidanti, antitirosinasiche ed antielastasiche di sericine ottenute con due processi differenti. In particolare, è stata considerata la sericina estratta da bozzoli di Bombyx mori, mediante processi ad-hoc sviluppati nei laboratori di ricerca, e la sericina isolata dalle acque reflue dellindustria tessile. Le sericine così ottenute sono state poi sottoposte a tre differenti trattamenti di conservazione: liofilizzazione, spray drying o sterilizzazione. I risultati ottenuti dimostrano come le sericine provenienti da entrambe le fonti mostrano attività antiossidante, la quale, tuttavia, risulta essere nettamente superiore nel caso dei campioni ottenuti mediante processo di sgommatura in laboratorio, rispetto alle sericine recuperate dalle acque reflue. In relazione al tipo di trattamento di conservazione, lessiccamento, sia mediante liofilizzazione che spray drying, si configura come il metodo più indicato per il mantenimento dellattività di ROS-scavenging. Lanalisi dellattività antitirosinasica della sericina recuperata dalle acque reflue sottoposta a successiva liofilizzazione mostra risultati promettenti: i campioni denotano unattività maggiore, seppur di poco, rispetto ai campioni di sericina ottenuta mediante sgommatura in laboratorio sottoposta al medesimo trattamento. Le sericine sottoposte a spray drying o sterilizzazione, indipendentemente dalla fonte, mostrano, infatti, livelli nettamente inferiori. Tutti i gruppi di sericina mostrano attività inibitorie nei confronti dellenzima elastasi. Anche in questo caso la sericina estratta dalle acque reflue dellindustria tessile mostra unattività simile ai campioni ottenuti mediante metodi di sgommatura in laboratorio. In particolare, i risultati più promettenti sono stati ottenuti testando campioni di sericina da fonte reflua successivamente sottoposti a spray drying, i quali hanno mostrato le maggiori proprietà antielastasiche. In conclusione, la sericina recuperata da acque reflue presenta buone proprietà antitirosinasiche, antielestasiche e antiossidanti e pertanto può essere impiegata come componente bioattivo di prodotti ad uso dermatologico e cosmetico e quindi destinata ad un processo di rivalorizzazione, in accordo ad un sistema economico pianificato per poterla riutilizzare in successivi cicli produttivi.
Sericina nativa e da acque reflue dell' industria tessile per uso farmaceutico
ANGELO, GAETANA
2018/2019
Abstract
Silk is a fiber of protein nature, of animal origin, which is extracted from cocoons of spiders of the class of Arachnida and from Lepidoptera such as mites, butterflies and moths. It consists essentially of two structural filaments of fibroin, a "core" protein, coated with sericin, a "glue" protein. Of the two proteins only the fibroin is part of the production process: the sericin must be removed from the fibroin so that the fiber acquires shine, softness, smoothness, whiteness and dyeability. Sericin, as a waste obtained from industrial processes in the textile sector, is present in the effluents of silk processing, generating an environmental problem of water pollution. Despite being considered a waste material in the textile industry, sericin is a biologically active protein that has attracted the interest of the scientific community for its potential use in the pharmaceutical field. In accordance with the waste valorisation process and the rules of environmental sustainability of the circular economy, recovering the sericin from wastewater would give two significant advantages: a lower environmental impact and the attainment of a precious raw material with high added value, intended for application in the most diverse sectors, particularly in the production of cosmetic products and in dermatology. The purpose of the thesis is to evaluate the antioxidant, antityrosinase and antielastase biological properties of sericins obtained with two different processes. In particular, the sericin extracted from Bombyx mori coocon was considered, using ad-hoc processes developed in research laboratories, and sericin isolated from the wastewater of the textile industry. The sericins thus obtained were then subjected to three different preservation treatments: lyophilization, spray drying or sterilization. The results obtained demonstrate how the sericins from both sources show antioxidant activity, which, however, appears to be much higher in the case of samples obtained through the degumming process in the laboratory, compared to the sericins recovered from wastewater. In relation to the type of conservation treatment, drying, both by freeze-drying and spray-drying, is the most suitable method for maintaining ROS-scavenging activity. The analysis of the anti-thyrosinase activity of the sericin recovered from the wastewater subjected to the subsequent lyophilization shows promising results: the samples show a greater activity, albeit slightly, compared to the samples of sericin obtained by degumming in the laboratory subjected to the same treatment. The sericines subjected to spray drying or sterilization, regardless of the source, show, in fact, significantly lower levels. All sericin groups show inhibitory activity against the enzyme elastase. Also in this case the sericin extracted from the wastewater of the textile industry shows a similar activity to the samples obtained by degumming methods in the laboratory. In particular, the most promising results were obtained by testing samples of sericin from wastewater subsequently subjected to spray drying, which showed the greatest antielastase properties. In conclusion, the sericin recovered from wastewater has good antitirosinase, antielestase and antioxidant properties and therefore it can be used as a bioactive component of products for dermatological and cosmetic use and therefore destined to a revaluation process, according to a planned economic system to be able to reuse in subsequent production cycles.È consentito all'utente scaricare e condividere i documenti disponibili a testo pieno in UNITESI UNIPV nel rispetto della licenza Creative Commons del tipo CC BY NC ND.
Per maggiori informazioni e per verifiche sull'eventuale disponibilità del file scrivere a: unitesi@unipv.it.
https://hdl.handle.net/20.500.14239/20161