New selective and sustainable ultrasound-assisted extraction procedure to recover carnosic and rosmarinic acids from Rosmarinus officinalis by sequential use of bio-based solvents.

Carnosic (CA) and rosmarinic (RA) acids are the primary phenolic acids in hydrophilic rosemary extracts. Their combination exhibits high antioxidant activity and can be explored in several applications. This study aimed to develop an extraction procedure using bio-based solvents to recover two rosemary extracts, one rich in CA and the other in RA. By using ultrasound-assisted extraction (UAE) and a pool of 34 solvents, we evaluated nominal power (W), extraction time (min), and solvent water percentage (% H2O) regarding yield and selectivity. The authors propose a sequential UAE procedure validated by applying ethanol 99.5 % (v/v), 240 W, and 5 min to recover a rich fraction of 24.0 mgCA.gbiomass-1; followed by a second step using AmAc:LA (1:2 M ratio), 20 % H2O (m/m), 320 W, and 5 min that resulted in 8.4 mgRA.gbiomass-1. Our results indicate that modulating the solvent composition and process temperature is critical to increasing extraction yields and selectivity.

Fast and green universal method to analyze and quantify anthocyanins in natural products by UPLC-PDA.

This work developed a universal UPLC-PDA method based on safe reagents to analyze anthocyanins from different foods. Nine foods were studied by the developed chromatographic method, which was constructed using a solid core C18 column and a binary mobile phase composed of (A) water (0.25 molcitric acid.Lsolvent-1), and (B) ethanol. A total running time of 6 min was obtained, the faster comprehensive method for anthocyanins analysis. Mass spectrometry analysis was employed to identify a comprehensive set of 53 anthocyanins comprising glycosylated and acylated cyanidin, pelargonidin, malvidin, peonidin, petunidin, and delphinidin derivatives. Cyanidin-3-O-glucoside (m/z+ 449) and cyanidin-3-O-rutinoside (m/z+ 595) were used as standards to validate the accuracy of the developed method. The analytical parameters were evaluated, including intra-day and inter-day precision, robustness, repeatability, retention factor (k), resolution, and peak symmetry factor. The current method demonstrated excellent chromatographic resolution, making it a powerful tool for analyzing anthocyanins pigments.

Application of an integrative system (2D PLE×HPLC-PDA) for bioactive compound extraction and online quantification: Advantages, validation, and considerations.

Analyzing compounds such as polyphenols in solid samples frequently uses a solid-liquid extraction step. The solid-liquid extraction and analysis integration in a single equipment is not commercially available since several challenges are inherent to this hybridization. In the context of developing more sustainable analytical procedures, innovative techniques are demanded. Given that, this work proposes a new integrative system (2D PLE × HPLC-PDA) and presents its validation for bioactive compound extraction and online quantification, discussing the main advantages and cares that need to be taken. Two food byproducts - passion fruit bagasse and coffee husks - were chosen as solid model samples. The system was configured to perform pressurized liquid extraction (PLE) with periodical automated extract injection in the HPLC, consequently obtaining the online quantification of target compounds from the solid samples. In parallel with the online injections, extract fractions were collected and submitted to offline analysis in which the extraction yield of piceatannol and chlorogenic acid and caffeine were evaluated, respectively, for passion fruit bagasse and coffee husks. The extraction yields obtained by online and offline injections were compared and were significantly equal (p > 0.05). Thus, the 2D PLE × HPLC-PDA system represents a feasible tool to integrate solid sample preparation and chemical analysis of biocompounds in a single and online step.

Combining eutectic solvents and food-grade silica to recover and stabilize anthocyanins from grape pomace.

Concentrated in the skins of red grapes are the anthocyanins, the primary colorants responsible for the fruits' reddish-purple color. These colorants are recognized for their significant antioxidant properties and potent nutraceutical and pharmaceutical ingredients. Nevertheless, their widespread use is compromised by the (i) need for more efficient yet sustainable downstream processes for their recovery and (ii) by the challenges imposed by their poor stability. In this work, these drawbacks were overcome by applying eutectic solvents and stabilizing agents. Besides, the anthocyanins were successfully loaded into a solid host material (approved in both food and pharmaceutical sectors) based on silicon dioxide (SiO2, loading capacity: 1extract:7silica m/m). Summing up, with the process developed, the extraction yield (21 mganthocyanins.gbiomass-1) and the stability (under 55, 75, and 95 °C) of the recovered anthocyanins were over three times better than with the conventional process. Finally, the raw materials and solvents were recycled, allowing an economical and environmentally friendly downstream process.

Ultra-high-performance liquid chromatography using a fused-core particle column for fast analysis of propolis phenolic compounds.

Propolis is a bee product with a complex chemical composition formed by several species from different geographical origins. The complex propolis composition requires an accurate and reproducible characterization of samples to standardize the quality of the material sold to consumers. This work developed an ultra-high-performance liquid chromatography with a photodiode array detector method to analyze propolis phenolic compounds based on the two key propolis biomarkers, Artepillin C and p-Coumaric acid. This choice was made due to the complexity of the sample with the presence of several compounds. The optimized method was hyphenated with mass spectrometry detection allowing the detection of 23 different compounds. A step-by-step strategy was used to optimize temperature, flow rate, mobile phase composition, and re-equilibration time. Reverse-phase separation was achieved with a C18 fused-core column packed with the commercially available smallest particles (1.3 nm). Using a fused-core column with ultra-high-performance liquid chromatography allows highly efficient, sensitive, accurate, and reproducible determination of compounds extracted from propolis with an outstanding sample throughput and resolution. Optimized conditions permitted the separation of the compounds in 5.50 min with a total analysis time (sample-to-sample) of 6.50 min.

Standardization proposal to quality control of propolis extracts commercialized in Brazil : A fingerprinting methodology using a UHPLC-PDA-MS/MS approach.

Propolis is a rich source of known and largely explored bioactive compounds with many pharmacological properties. It is used in several commercialized products, such as propolis-enriched honey, candies, mouth and throat sprays, soaps, toothpaste, and skin creams. However, the great diversity of propolis products and different types make the standardization of realistic quality control procedures challenging. Moreover, the extraction of propolis bioactive compounds depends on the technique and the solvent used. In Brazil, the Ministry of Agriculture, Livestock, and Supply (MAPA) set standards to establish commercialized propolis extracts' identity and quality. In addition, according to legislation, propolis extracts must present the main classes of phenols at 200 and 400 nm on the UV spectrum. Still, it is not specified which analysis method should be used to guarantee feasible quality control of the commercialized samples. For this, we proposed a new fast UHPLC-PDA-MS/MS method for analysis and quantification of propolis phenolic compounds. Moreover, we hypothesize that there is no efficient monitoring regarding the quality of the propolis extracts sold in Brazilian stores. Therefore, the present study aimed to perform quality control of 17 Brazilian propolis extracts produced in the Southeast region (green or brown - the most representative samples). The dry extract content (% g/mL), oxidation index (seconds), total flavonoids, and phenolics (% m/m) of each sample were compared with legislation. We conclude that using the UHPLC-PDA method and the investigation that allowed the comparison with the current legislation efficiently practical problems in the commercialization of propolis extracts. However, of the 17 analyzed samples, 6 did not meet the desired the recognized standards, denoting a lack of supervision and efficient quality control, which highlights a dangerous situation regarding the commercialization of this critical product used in several industrial fields, mainly in the food and pharmaceutical sector.

Insights on the Extraction and Analysis of Phenolic Compounds from Citrus Fruits: Green Perspectives and Current Status.

Citrus fruits (CF) are highly consumed worldwide, fresh, processed, or prepared as juices and pies. To illustrate the high economic importance of CF, the global production of these commodities in 2021 was around 98 million tons. CF's composition is considered an excellent source of phenolic compounds (PC) as they have a large amount and variety. Since ancient times, PC has been highlighted to promote several benefits related to oxidative stress disorders, such as chronic diseases and cancer. Recent studies suggest that consuming citrus fruits can prevent some of these diseases. However, due to the complexity of citrus matrices, extracting compounds of interest from these types of samples, and identifying and quantifying them effectively, is not a simple task. In this context, several extractive and analytical proposals have been used. This review discusses current research involving CF, focusing mainly on PC extraction and analysis methods, regarding advantages and disadvantages from the perspective of Green Chemistry.

Recent advances and trends in extraction techniques to recover polyphenols compounds from apple by-products.

Apple is one of the most consumed fruits worldwide and has recognized nutritional properties. Besides being consumed fresh, it is the raw material for several food products, whose production chain generates a considerable amount of by-products that currently have an underestimated use. These by-products are a rich source of chemical compounds with several potential applications. Therefore, new ambitious platforms focused on reusing are needed, targeting a process chain that achieves well-defined products and mitigates waste generation. This review covers an essential part of the apple by-products reuse chain. The apple composition regarding phenolic compounds subclasses is addressed and related to biological activities. The extraction processes to recover apple biocompounds have been revised, and an up-to-date overview of the scientific literature on conventional and emerging extraction techniques adopted over the past decade is reported. Finally, gaps and future trends related to the management of apple by-products are critically presented.