Antioxidant activity and stability of 6-amino-6-deoxy-L-ascorbic acid and N-methyl-6-amino-6-deoxy-L-ascorbic acid and their potential use in the cosmetic industry

L-askorbinska kiselina (vitamin C) i njeni derivati imaju važnu fiziološku funkciju u ljudskom organizmu. Uz upotrebu kao dodatak prehrani, na tržištu postoji mnoštvo topikalnih formulacija L-askorbinske kiseline i derivata koji potiču sintezu kolagena, učvršćuju kožu, spriječavaju i djeluju povratno na promjene uzrokovane hiperpigmentacijom te općenito poboljšavaju izgled kože. U kozmetičkim se proizvodima također koristi kao antioksidans, podešivač pH vrijednosti te fotoprotektivni agens. Zbog osjetljivosti na vanjske čimbenike poput temperature, prisutnosti kisika, svjetlosti i pH, L-askorbinska se kiselina u formulacijama stabilizira agensima poput vitamina E i ferulične kiseline. Uz kemijsku stabilizaciju, važna je također stroga kontrola uvjeta tijekom formulacije (razina kisika, pH, i sl.). Osim kontrole uvjeta proizvodnje i dodatka stabilizirajućih agenasa, kemijske su modifikacije molekule dovele do razvoja stabilnih derivata poput natrijevog askorbil fosfata i magnezijevog askorbil fosfata. Iako su navedeni derivati stabilniji od L-askorbinske kiseline, nedostaje im snažniji farmakološki učinak. U ovom radu ispitana je antioksidativna aktivnost i stabilnost novosintetiziranih derivata 6-amin-6-deoksi-L-askorbinske kiseline i N-metil-6-amin-6-deoksi-L-askorbinske kiseline, kemijskim metodama ABTS i DPPH. Uz navedeno, ispitani su optimalni uvjeti skladištenja te je MS/MS analizom određena pH vrijednost pri kojoj derivati zadržavaju stabilnost. Rezultati su pokazali da novosintetizirani derivati posjeduju antioksidativnu aktivnost usporedivu s L-askorbinskom kiselinom te su stabilni u kiselom mediju tijekom 30 dana. Potvrdom antioksidativne aktivnost i stabilnosti derivata, napravljen je temelj za daljnja biološka in vitro ispitivanja.L-Ascorbic acid (vitamin C) and its derivatives perform important physiological functions in the human organism. Except dietary supplements, numerous topical formulations containing L-ascorbic acid and its derivatives are available on the market. These formulations induce collagen synthesis, strengthening of skin tissue, reduction in hyperpigmentation spots and improvement of overall skin health. L-ascorbic acid has also been used as antioxidant, pH adjuster and photoprotecting agent in cosmetic products. Due to it's sensitivity to external factors such as temperature, presence of oxygen, light an pH, L-ascorbic acid is combined with stabilizing agents such as vitamin E and ferulic acid. Along chemical stabilization, strict control of production conditions is required (oxygen level, pH, etc.). Except controlling of production conditions and adding stabilizing agents, chemical modifications of this molecule have led to stable derivatives development. Well known L-ascorbic acid derivatives, such as magnesium ascorbyl phosphate and sodium ascorbyl phosphate are more stable than L-ascorbic acid but they lack the pharmacological activity of L-ascorbic acid. In this thesis, the antioxidant activity and stability of 6-amino-6-deoxy-L-ascorbic acid and N-methyl-6-amino-6-deoxy-L-ascorbic acid have been examined using ABTS and DPPH assays. In addition, optimal storing conditions, as well as the pH at which new synthesised derivatives maintain the stability, were determined using mass sepctrometry. Results have shown the similarity in antioxidative activity between the new synthesised derivatives and L-ascorbic acid. In addition, these derivatives showed good stability in acidic medium during 30 days. By proving the antioxidative activity and antioxidative stability of synthesised L-ascorbic acid derivatives, we made a base for a further biological tests

Antioxidant activity and stability of 6-amino-6-deoxy-L-ascorbic acid and N-methyl-6-amino-6-deoxy-L-ascorbic acid and their potential use in the cosmetic industry

L-askorbinska kiselina (vitamin C) i njeni derivati imaju važnu fiziološku funkciju u ljudskom organizmu. Uz upotrebu kao dodatak prehrani, na tržištu postoji mnoštvo topikalnih formulacija L-askorbinske kiseline i derivata koji potiču sintezu kolagena, učvršćuju kožu, spriječavaju i djeluju povratno na promjene uzrokovane hiperpigmentacijom te općenito poboljšavaju izgled kože. U kozmetičkim se proizvodima također koristi kao antioksidans, podešivač pH vrijednosti te fotoprotektivni agens. Zbog osjetljivosti na vanjske čimbenike poput temperature, prisutnosti kisika, svjetlosti i pH, L-askorbinska se kiselina u formulacijama stabilizira agensima poput vitamina E i ferulične kiseline. Uz kemijsku stabilizaciju, važna je također stroga kontrola uvjeta tijekom formulacije (razina kisika, pH, i sl.). Osim kontrole uvjeta proizvodnje i dodatka stabilizirajućih agenasa, kemijske su modifikacije molekule dovele do razvoja stabilnih derivata poput natrijevog askorbil fosfata i magnezijevog askorbil fosfata. Iako su navedeni derivati stabilniji od L-askorbinske kiseline, nedostaje im snažniji farmakološki učinak. U ovom radu ispitana je antioksidativna aktivnost i stabilnost novosintetiziranih derivata 6-amin-6-deoksi-L-askorbinske kiseline i N-metil-6-amin-6-deoksi-L-askorbinske kiseline, kemijskim metodama ABTS i DPPH. Uz navedeno, ispitani su optimalni uvjeti skladištenja te je MS/MS analizom određena pH vrijednost pri kojoj derivati zadržavaju stabilnost. Rezultati su pokazali da novosintetizirani derivati posjeduju antioksidativnu aktivnost usporedivu s L-askorbinskom kiselinom te su stabilni u kiselom mediju tijekom 30 dana. Potvrdom antioksidativne aktivnost i stabilnosti derivata, napravljen je temelj za daljnja biološka in vitro ispitivanja.L-Ascorbic acid (vitamin C) and its derivatives perform important physiological functions in the human organism. Except dietary supplements, numerous topical formulations containing L-ascorbic acid and its derivatives are available on the market. These formulations induce collagen synthesis, strengthening of skin tissue, reduction in hyperpigmentation spots and improvement of overall skin health. L-ascorbic acid has also been used as antioxidant, pH adjuster and photoprotecting agent in cosmetic products. Due to it's sensitivity to external factors such as temperature, presence of oxygen, light an pH, L-ascorbic acid is combined with stabilizing agents such as vitamin E and ferulic acid. Along chemical stabilization, strict control of production conditions is required (oxygen level, pH, etc.). Except controlling of production conditions and adding stabilizing agents, chemical modifications of this molecule have led to stable derivatives development. Well known L-ascorbic acid derivatives, such as magnesium ascorbyl phosphate and sodium ascorbyl phosphate are more stable than L-ascorbic acid but they lack the pharmacological activity of L-ascorbic acid. In this thesis, the antioxidant activity and stability of 6-amino-6-deoxy-L-ascorbic acid and N-methyl-6-amino-6-deoxy-L-ascorbic acid have been examined using ABTS and DPPH assays. In addition, optimal storing conditions, as well as the pH at which new synthesised derivatives maintain the stability, were determined using mass sepctrometry. Results have shown the similarity in antioxidative activity between the new synthesised derivatives and L-ascorbic acid. In addition, these derivatives showed good stability in acidic medium during 30 days. By proving the antioxidative activity and antioxidative stability of synthesised L-ascorbic acid derivatives, we made a base for a further biological tests

Antioxidant activity and stability of 6-amino-6-deoxy-L-ascorbic acid and N-methyl-6-amino-6-deoxy-L-ascorbic acid and their potential use in the cosmetic industry

L-askorbinska kiselina (vitamin C) i njeni derivati imaju važnu fiziološku funkciju u ljudskom organizmu. Uz upotrebu kao dodatak prehrani, na tržištu postoji mnoštvo topikalnih formulacija L-askorbinske kiseline i derivata koji potiču sintezu kolagena, učvršćuju kožu, spriječavaju i djeluju povratno na promjene uzrokovane hiperpigmentacijom te općenito poboljšavaju izgled kože. U kozmetičkim se proizvodima također koristi kao antioksidans, podešivač pH vrijednosti te fotoprotektivni agens. Zbog osjetljivosti na vanjske čimbenike poput temperature, prisutnosti kisika, svjetlosti i pH, L-askorbinska se kiselina u formulacijama stabilizira agensima poput vitamina E i ferulične kiseline. Uz kemijsku stabilizaciju, važna je također stroga kontrola uvjeta tijekom formulacije (razina kisika, pH, i sl.). Osim kontrole uvjeta proizvodnje i dodatka stabilizirajućih agenasa, kemijske su modifikacije molekule dovele do razvoja stabilnih derivata poput natrijevog askorbil fosfata i magnezijevog askorbil fosfata. Iako su navedeni derivati stabilniji od L-askorbinske kiseline, nedostaje im snažniji farmakološki učinak. U ovom radu ispitana je antioksidativna aktivnost i stabilnost novosintetiziranih derivata 6-amin-6-deoksi-L-askorbinske kiseline i N-metil-6-amin-6-deoksi-L-askorbinske kiseline, kemijskim metodama ABTS i DPPH. Uz navedeno, ispitani su optimalni uvjeti skladištenja te je MS/MS analizom određena pH vrijednost pri kojoj derivati zadržavaju stabilnost. Rezultati su pokazali da novosintetizirani derivati posjeduju antioksidativnu aktivnost usporedivu s L-askorbinskom kiselinom te su stabilni u kiselom mediju tijekom 30 dana. Potvrdom antioksidativne aktivnost i stabilnosti derivata, napravljen je temelj za daljnja biološka in vitro ispitivanja.L-Ascorbic acid (vitamin C) and its derivatives perform important physiological functions in the human organism. Except dietary supplements, numerous topical formulations containing L-ascorbic acid and its derivatives are available on the market. These formulations induce collagen synthesis, strengthening of skin tissue, reduction in hyperpigmentation spots and improvement of overall skin health. L-ascorbic acid has also been used as antioxidant, pH adjuster and photoprotecting agent in cosmetic products. Due to it's sensitivity to external factors such as temperature, presence of oxygen, light an pH, L-ascorbic acid is combined with stabilizing agents such as vitamin E and ferulic acid. Along chemical stabilization, strict control of production conditions is required (oxygen level, pH, etc.). Except controlling of production conditions and adding stabilizing agents, chemical modifications of this molecule have led to stable derivatives development. Well known L-ascorbic acid derivatives, such as magnesium ascorbyl phosphate and sodium ascorbyl phosphate are more stable than L-ascorbic acid but they lack the pharmacological activity of L-ascorbic acid. In this thesis, the antioxidant activity and stability of 6-amino-6-deoxy-L-ascorbic acid and N-methyl-6-amino-6-deoxy-L-ascorbic acid have been examined using ABTS and DPPH assays. In addition, optimal storing conditions, as well as the pH at which new synthesised derivatives maintain the stability, were determined using mass sepctrometry. Results have shown the similarity in antioxidative activity between the new synthesised derivatives and L-ascorbic acid. In addition, these derivatives showed good stability in acidic medium during 30 days. By proving the antioxidative activity and antioxidative stability of synthesised L-ascorbic acid derivatives, we made a base for a further biological tests

Maturation of wine in underwater springs as a novel wine production process

The technological process of wine production affects its chemical composition and consequently its organoleptic properties. Therefore, innovative technologies in wine production are of great importance in the competitive wine market. The maturation of wine in underwater springs is a novel technological process that, except for adding an attractive appearance to the wine bottle, potentially influences the wine's chemical composition. Herein, we performed total phenolic and flavonoid content analysis, phenolic profiling, and determined antioxidant potential for Malvasia white wines matured in traditional cellars and in the Northern Adriatic underwater springs. The antioxidant potential and total phenol and flavonoid content did not show significant differences between the two wine maturation processes. However, LC–MS/MS quantitative analysis showed that wines matured in the underwater springs had significantly increased concentrations of naringenin and myricetin. Despite the lack of a significant difference in chemical composition measured by less sensitive spectrophotometric methods, the quantitative differences of phenolic compounds were persistent and, as such, are a stimulus for further development and optimization of new wine production technologies including wine maturation in underwater springs

Flour - Bread '19 : Proceedings of the 10th International Congress Flour - Bread '19 and 12th Croatian Congress of Cereal Technologists Brašno - Kruh '19

Proceedings contains 3 Reviews, 8 Original research articles and 3 Professional articles presented at 10th International Congress Flour – Bread ’19 and 12th Croatian Congress of Cereal Technologists Brašno – Kruh ’1

Proceedings Of The 23Rd Paediatric Rheumatology European Society Congress: Part Two

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