Bøger af João Pedro Mesquita Oliveira

Zbadali w bezprecedensowy sposób profil chemiczny, dzialanie przeciwutleniajace i przeciwzapalne nanoczasteczek srebra (AgNPs) syntetyzowanych z nanoemulsji olejku eterycznego Piper nigrum (NEO). Nanoemulsje przygotowano metoda inwersji faz, a synteze AgNP przeprowadzono metoda redukcji Agno3 Ag z uzyciem NEO. Aktywnosc przeciwutleniajaca oceniano metoda barwienia rodnikowego Abts, a aktywnosc przeciwzapalna metoda denaturacji bialek. Glównym skladnikiem TE byl limonen (42,41%). Maksymalne pasmo Spr bylo wysrodkowane przy 420 nm, co wskazuje na charakterystyczny pik AgNP. Najnizsza wartosc IC50 wynoszaca 16,26 mg L-1 dla aktywnosci przeciwutleniajacej uzyskano dla AgNP pH 11. Wartosc IC50 wykazujaca najlepszy wynik dla dzialania przeciwzapalnego przy pH 11 wyniosla 0,217 mg mL-1. Badanie to przynioslo bezprecedensowe wyniki dla AgNP P. nigrum i okazalo sie skuteczne we wzmacnianiu aktywnosci testowanych w tym badaniu.

Investigated in an unprecedented way the chemical profile, antioxidant and anti-inflammatory activity of silver nanoparticles (AgNPs) synthesized from Piper nigrum essential oil nanoemulsion (NEO). The nanoemulsions were prepared with the phase inversion method and the synthesis of AgNPs was performed with the Agno3 Ag reduction method using NEO. Antioxidant activity was evaluated by Abts radical staining method and anti-inflammatory activity by protein denaturation. The main component of the EO was limonene (42.41%). The maximum Spr band was centered at 420 nm, indicating the characteristic peak of AgNPs. The lowest IC50 value of 16.26 mg L-1 for antioxidant activity was obtained for AgNP pH 11. The IC50 value showing the best result for anti-inflammatory activity at pH 11 was 0.217 mg mL-1. This study yielded unprecedented results for P. nigrum AgNPs and proved efficient in enhancing the activities tested in this study.

It was evaluated the chemical profile, antioxidant and anti-inflammatory activity, in an unprecedented way, of silver nanoparticles (AgNPs) synthesized from the essential oil nanoemulsion (NEO) of Piper nigrum. For essential oil extraction (EO), the hydrodistillation technique was used and the chemical constituents were identified by Gas Chromatography Coupled to Mass Spectrometry (GC-MS). The nanoemulsions were prepared using the phase inversion method and the synthesis of the AgNPs were performed by the Agno3 Ag reduction method using NEO. Antioxidant activity was evaluated using the abts radical discoloration method and anti-inflammatory activity by protein denaturation. The majority constituent of the EO was limonene (42.41%). The maximum spr band was centered at 420 nm indicating the characteristic peak of the AgNPs. The lowest IC50 16.26 mg L-1 for antioxidant activity was obtained for AgNP pH 11. The IC50 that demonstrated the best result for anti-inflammatory activity was pH 11 was 0.217 mg mL-1. This study brought in an unprecedented way results for AgNPs of P. nigrum, demonstrating to be efficient in improving the activities tested in this study.

Nanoemulsions are considered as a way to innovate as activities of essential oils in view of their potential as a finer dispersion resulting from the incorporation of an aqueous and an oily phase. Thus, this study determined the chemical constituents and larvicidal activity of the nanoemulsion. P. guajava leaves and essential oil were collected by hydrodistillation technique. The chemical constituents were obtained by Gas Chromatography coupled with Mass Spectrometry (GC/MS). The total phenolic content was quantified by the Folin-Ciocalteau spectrophotometric method. For toxicity test, Artemia salina was applied for bioassay. The nanoemulsion (W/A) was prepared using the low energy phase inversion method. The LC50 was concluded for the action of the nanoemulsion against Aedes aegypti larvae by the Probit method. The main chemical constituent found in P. guajava essential oil was ¿-Pinene 34.25%. Phenolics were quantified at 210.35 mg EAT g-1. Without toxicity bioassay, LC50 323.6 mg L-1 was classified as non-toxic.

Это исследование направлено на оценку химического профиля и фунгицидной активности наноэмульсии эфирного масла, полученного из Ba-har (сирийского перца). Результаты, полученные для общего содержания фенолов, были количественно определены в 348,3 мг EAT г-1 и 346,21 мг EQ г-1 для флавоноидов. Эфирное масло Ba-har было более эффективным в подавлении A niger, поскольку он показал самый низкий МПК (200 мкг / мл), за ним следовали P. chrysogenum (250 мкг / мл), а затем - C. gloeosporioides (300 мкг / мл). Идентификация вторичных метаболитов, присутствующих в Ba-har, была довольно значительной, поскольку они отвечают за биологические свойства, что вдохновляет на непрерывность исследований, связанных с его биологической активностью. Что касается общего содержания фенолов и флавоноидов, присутствующих в эфирном масле, они указали на важный антиоксидантный потенциал. Фунгицидный потенциал масла Ba-har показал сильное ингибирование и гибель, однако продукт наноэмульсии с включенным эфирным маслом показал более эффективное действие против тестируемых патогенных грибов.