Development of ophthalmic nanoemulsions of ß-caryophyllene for the treatment of Acanthamoeba keratitis.

Although rare, amoebic keratitis (AK) is a disease caused by Acanthamoeba spp. that can lead to blindness. The drugs currently available for its treatment are very toxic, which has motivated the investigation for more effective and safe therapeutic options. In this study, the in vitro activity of ß-caryophyllene (BCP) was exploited taking into account its action against other protozoans as well as its well-known healing and anti-inflammatory properties (aspects relevant for the AK pathogenesis). On the other hand, high volatilization and oxidation phenomena are found for this compound, which led to its incorporation into nanoemulsions (NEs). Two emulsifying agents were tested, resulting in monodisperse systems with reduced droplet size (<265 nm) and high surface charge (positive and negative for NEs prepared with cetrimonium bromide -CTAB and Phosal® 50+, respectively). NEs prepared with CTAB were shown to be more stable after long-term storage at 4 and 25 °C than those prepared with Phosal®. Pure BCP, at the highest concentration (500 µM), resulted in a level of inhibition of Acanthamoeba trophozoites equivalent to that of reference drug (chlorhexidine). This activity was even greater after oil nanoencapsulation. The reduced droplet size could improve the interaction of the oil with the microorganism, justifying this finding. Changes in surface charge did not impact the activity. Positively charged NEs improved the interaction and retention of BCP in the cornea and thus should be prioritized for further studies.

Simultaneous extraction/derivatization for the analysis of sulfite by capillary electrophoresis: A high-throughput reference method to meet the demand of seafood inspection.

Sulfite is widely used to prevent enzymatic browning in shrimp and lobster processing. However, sulfite may cause allergy in sensitive consumers. Thus, regulatory agencies set limits for its use. Sulfite is usually controlled by the normalized Monier-Williams (MW) titrimetric method that allows a limited number of samples to be analyzed. This manuscript consolidates an innovative method for sulfite inspection in seafood by capillary zone electrophoresis with diode array detector (CZE-DAD). A simple, fast, and simultaneous extraction and derivatization method was developed to provide high throughput for analytical routine. The high instability of the sulfite was suppressed by its derivatization with formaldehyde producing hydroxymethylsulfonate. The evaluation of its analytical performance yielded excellent results in compliance with the strict parameters required for metrological accreditation. The CZE-DAD method was selective and specific when submitted to confirmatory evaluations by liquid chromatography coupled to mass spectrometry. The limit of detection (3.50 mg kg-1), limit of quantitation (11.7 mg kg-1) and recoveries (99-103%) were adequate for sample analysis. The measurement uncertainty was estimated by the propagation of errors and experimental standard uncertainties (precision, accuracy, and analytical curves) and type B uncertainties from traceable measurement instruments. The low relative uncertainty (10%) and the adequate reproducibility demonstrated method suitability. The CZE-DAD results were compared to the MW method through the respective expanded standard uncertainties and normalized error. This new method is promising to be used in seafood inspection and continuous laboratory evaluations using instrumentation not very expensive to acquire and maintain.

Grumixama (Eugenia brasiliensis Lamarck) functional phytochemicals: Effect of environmental conditions and ripening process.

Grumixama (Eugenia brasiliensis Lamarck) is a native fruit of the Atlantic rain forest that belongs to Myrtaceae family. It presents economic potential due to the attractive sensory attributes and bioactive compounds. This study determined physicochemical characteristics, minerals (K, Na, Ca, Mg, Mn), sugars (fructose, glucose, sucrose), total content of phenolics, proanthocyanidins, and anthocyanins, individual phenolic compounds, and antioxidant capacity at three ripening stages of grumixama from two growing locations (Florianópolis and São Ludgero, Santa Catarina state, Brazil). Of the 23 phenolic compounds quantified, gallic acid, ellagic acid, quercetin, and isoquercetrin were the major (with values up to 69.08 mg/100 g fresh weight). Fructose (up to 5.28 g/100 g fresh weight) was the main sugar, and K (up to 589.30 mg/100 g fresh weight) was the major mineral, followed by Ca, Na, and Mg (up to 149.02, 117.52, and 80.18 mg/100 g fresh weight, respectively). More mature fruits had the highest levels of total phenolics (up to 469.18 mg gallic acid equivalent/100 g fresh weight), anthocyanins (up to 518.64 mg cyanidin 3-glucoside equivalent/100 g fresh weight), and proanthocyanidins (up to 420.70 mg catechin equivalent/100 g fresh weight). The influence of growing location and ripening on nutritional and physicochemical characteristics was confirmed. There was a statistically significant interaction (p < 0.05) between both factors for almost all parameters evaluated. The results showed that grumixama fruits could contribute to the daily intake of nutritional and bioactive compounds for consumers' health.

Increasing the instrumental throughput of gas chromatography method using multiple injections in a single experimental run: application in determination of friedelan-3-ol and friedelin in Maytenus ilicifolia.

The aim of this study was to develop a separation method using multiple injections in a single experimental run (MISER) employing gas chromatography with flame ionization detection (GC-FID) for the first time, without instrument modification, to increase the instrumental throughput. The method was applied to the determination of the triterpenes friedelan-3-ol and friedelin in a plant extract obtained from Maytenus ilicifolia leaves. The column used in the chromatography system was a ZB-50 (30 m × 0.25 mm × 0.15 µm) with 50% phenyl-50% methyl-polysiloxane. The samples (1.0 µL) were injected using the split mode (1:90), with the injector at 280 °C and FID detector at 320 °C. The column temperature was programmed to isothermal mode at 300°C. Helium was used as the carrier gas with a constant flow of 1.5 mL min(-1). It was possible to perform three injections in the same run using the MISER method. An increase in the instrumental throughput by a factor of around 2.6 was observed when the use of multiple injections was compared with the single injection method. This method showed good linearity for both analytes with R(2)>0.99 and the values for the limit of detection were 0.24 mg L(-1) and 0.44 mg L(-1), for friedelan-3-ol and friedelin, respectively. Furthermore, the values for the limits of quantification were 0.79 mg L(-1) for friedelan-3-ol and 1.16 mg L(-1) for friedelin. The proposed method has potential for other GC applications, allowing an increase in the instrumental throughput of the methods by applying this separation technique.