Rosemary (Rosmarinus officinalis L.) is known for its bioactive compounds with high antioxidant potential and pharmacological properties, such as antibacterial, antidepressant and anti-inflammatory. These properties are attributed to the presence of (poly)phenolic compounds. In the literature there is no extraction of these compounds with a totally non-toxic solvent, capable of applying the extract directly to the food. This work aimed to optimize the extraction conditions of bioactive compounds from the rosemary leaves using water as solvent. According to the analysis of variance parameters, a cubic model of high order of significance was obtained with adjusted R2 (R squared) > 0.947. The optimal conditions of the antioxidant potential for conventional and ultrasonic agitation were: temperature 70 °C, 30 min of extraction and the solvent/solute ratio of 25, resulting in an antioxidant potential of 6861 and 7126 µmol L−1 Trolox, respectively. The electrospray ionization mass spectrometry (ESI(−)-MS/MS) analysis showed the presence of antioxidant compounds such as: carnosol (m/z 329.20), rosmanol (m/z 345.03) and rosmarinic (m/z359.14) acids. The response surface methodology evaluated the influence of the main parameters of the bioactive compounds extraction from rosemary using only water as solvent, in addition to the use of less time and sample mass, resulting in lower cost.

This study evaluated the Chia (Salvia hispanica L.) oil composition in terms of fatty acids (FA), sterols, acylglycerols and oxidative stability obtained via subcritical n-propane fluid extraction (SubFE-propane), in different temperatures and pressure conditions, as compared to Bligh & Dyer (BD), Soxhlet (SE) and Folch (FLS) extractions. Total lipid varied from 23.25 to 30.21% and the best yield was obtained by both SubFE-propane extraction at 45 ºC and 12 MPa (A). α-Linolenic acid (18:3n-3) was the most abundant FA and SubFE-propane extraction provided the best results for the sum of n-3 and PUFA. All oil samples were similar in regard to triacylglycerols (TAG) profiles as measured via direct electrospray ionization mass spectrometry (ESI-MS) analysis. The total amounts of stigmasterol, β-tocopherol and tocopherol total were highest in the Chia oil obtained by BD, campesterol and sitosterol by SE and γ-tocopherol by SubFE-propane extraction. The SubFE-propane oil also presented the best (2 to 5 times) oxidation stability. SubFE-propane was the most efficient extraction method for Chia oil, providing the highest extraction yields, purity, oxidation stability and diverse profile of sterols.

Cada matriz alimentar é única. Os antioxidantes endógenos de um produto de panificação não estudados podem mostrar diferentes respostas para atividade antioxidante total (TAA)/resistência a oxidação forçada (ROF) do que é esperado para outros alimentos reportados na literatura. Neste contexto, um design Box-Behnken e estudos de correlação foram aplicados para obter mais informações sobre como compostos antioxidantes específicos afetam o TAA/ROF em pães com sementes de chia e folhas de cenoura. Hipóteses de sinergismo/antagonismo entre os compostos estudados foram elucidadas para tentar justificar os resultados obtidos. Neste tipo específico de amostra, carotenóides e colesterol tiveram as maiores relações com resultados de ensaios de TAA, bem como com pontos de indução provenientes do equipamento Oxitest®, enquanto que α-tocoferol e fitosteróis mostraram correlações negativas. Compostos fenólicos não tiveram nenhuma influência no sistema porque o cozimento em alta temperatura das amostras destruiu grande parte desses analitos.

Each food matrix is unique. Thus, the endogenous antioxidants of an underexplored bakery product might show different responses regarding free radical scavenging/resistance to forced oxidation than what is expected for other foods previously reported in the literature. In this context, a Box-Behnken design and correlation studies were applied in order to obtain more information about how specific antioxidants affect the total antioxidant activity (TAC) and the degree of forced oxidation in white breads with chia seeds and carrot leaves. Hypotheses of synergism/antagonism between the studied compounds were also elucidated in order to justify the obtained results. In this specific sample type, carotenoids and cholesterol showed the greatest relationships with results from TAC assays, as well with induction points using Oxitest® equipment, while α-tocopherol and phytosterols showed negative correlations. Phenolic compounds did not have any influence on the system because the baking procedure at high temperature had severe impacts on them.

A fotodegradação de biodiesel em contato com água, utilizando reação foto-Fenton, foi investigada neste estudo. Após 360 h de fotodegradação obteve-se uma redução de 73% dos ésteres metílicos de ácidos graxos (FAMEs) quantificados inicialmente por cromatografia em fase gasosa acoplada ao detector por ionização em chama (GC/FID). No decorrer da fotodegradação foram detectados picos para cetona e grupo epóxido nas cadeias alifáticas em análises por cromatografia em fase gasosa acoplada ao espectrômetro de massas (GC/MS), e deslocamentos típicos de aldeídos e ácidos graxos de cadeia curta em análises por espectroscopia de ressonância magnética nuclear de hidrogênio (¹H RMN). As análises de eco toxicidade usando como organismo teste Artemia salina evidenciaram componentes tóxicos na fase aquosa que aumentaram até 168 h de fotodegradação, apresentando decréscimo após este período.

This study reports on the photodegradation of biodiesel in contact with water using the photo-Fenton reaction. After 360 h of photodegradation, we observed a reduction of 73% in the amount of fatty acid methyl esters (FAMEs) initially quantified by gas chromatography coupled with a flame ionization detector (GC/FID). During the photodegradation, peaks for ketones and epoxy groups in carbon chains were recorded by gas chromatography coupled with mass spectrometry (GC/MS), and typical aldehyde and short-chain fatty acid shifts in hydrogen nuclear magnetic resonance spectroscopy (¹H NMR) were observed. Ecotoxicity assays with Artemia salina revealed the presence of toxic components in the aqueous phase in increasing amounts up to 168 h of photodegradation and decreasing thereafter.

The chemical study of the orchid Maxillaria picta resulted in the isolation of the bioactive stilbenes phoyunbene B and phoyunbene C, in addition to four phenolic acids, one xanthone, steroidal compounds and two triterpenes. Crude extract, fractions, subfractions and the isolated xanthone were evaluated for anticancer activity against human tumor cell lines and against evolutionary forms of T. cruzi and L. amazonensis. The structures of the compounds were determined by GC-MS, and ¹H NMR, 13C NMR spectral methods as well as bidimensional techniques.