A spectrophotometric analysis of extracted water-soluble phenolic metabolites of lichens.

MAIN CONCLUSION: Rainwater most probably constitutes a relatively effective solvent for lichen substances in nature which have the potential to provide for human and environmental needs in the future. The aims were (i) to test the hypothesis on the potential solubility of lichen phenolic compounds using rainwater under conditions that partly reflect the natural environment and (ii) to propose new and effective methods for the water extraction of lichen substances. The results of spectrophotometric analyses of total phenolic metabolites in rainwater-based extracts from epigeic and epiphytic lichens, employing the Folin-Ciocalteu (F.-C.) method, are presented. The water solvent was tested at three pH levels: natural, 3, and 9. Extraction methods were undertaken from two perspectives: the partial imitation of natural environmental conditions and the potential use of extraction for economic purposes. From an ecological perspective, room-temperature water extraction ('cold' method) was used for 10-, 60-, and 120-min extraction periods. A variant of water extraction at analogous time intervals was an 'insolation' with a 100W light bulb to simulate the heat energy of the sun. For economic purposes, the water extraction method used the Soxhlet apparatus and its modified version, the 'tea-extraction' method ('hot' ones). The results showed that those extractions without an external heat source were almost ineffective, but insolation over 60- and 120-min periods proved to be more effective. Both tested 'hot' methods also proved to be effective, especially the 'tea-extraction' one. Generally, an increase in the concentration of phenolic compounds in water extracts resulted from an increasing solvent pH. The results show the probable involvement of lichen substances in biogeochemical processes in nature and their promising use for a variety of human necessities.

Dataset for quantum-mechanical exploration of conformers and solvent effects in large drug-like molecules.

We here introduce the Aquamarine (AQM) dataset, an extensive quantum-mechanical (QM) dataset that contains the structural and electronic information of 59,783 low-and high-energy conformers of 1,653 molecules with a total number of atoms ranging from 2 to 92 (mean: 50.9), and containing up to 54 (mean: 28.2) non-hydrogen atoms. To gain insights into the solvent effects as well as collective dispersion interactions for drug-like molecules, we have performed QM calculations supplemented with a treatment of many-body dispersion (MBD) interactions of structures and properties in the gas phase and implicit water. Thus, AQM contains over 40 global and local physicochemical properties (including ground-state and response properties) per conformer computed at the tightly converged PBE0+MBD level of theory for gas-phase molecules, whereas PBE0+MBD with the modified Poisson-Boltzmann (MPB) model of water was used for solvated molecules. By addressing both molecule-solvent and dispersion interactions, AQM dataset can serve as a challenging benchmark for state-of-the-art machine learning methods for property modeling and de novo generation of large (solvated) molecules with pharmaceutical and biological relevance.

Preparation of Microsponge Drug Delivery System (MSDDS) Followed by a Scale-Up Approach.

In 1987, Won invented the solid-phase porous microsphere (MS), which stores bioactive compounds in many interconnected voids. Spherical particles (5-300 µm), MS, may form clusters of smaller spheres, resulting in many benefits. The current investigation focussed on gel-encased formulation, which can be suitable for dermal usage. First, quasi-emulsion (w/o/w) solvent evaporation was used to prepare 5-fluorouracil (5 FU) MS particles. The final product was characterized (SEM shows porous structure, FTIR and DSC showed drug compatibility with excipients, and gel formulation is shear-thinning) and further scaled up using the 8-fold method. Furthermore, CCD (Central Composite Design) was implemented to obtain the optimized results. After optimizing the conditions, including the polymer (600 mg, ethyl cellulose (EC), eudragit RS 100 (ERS)), stirring speed (1197 rpm), and surfactant concentration (2% w/v), we achieved the following results: optimal yield (63%), mean particle size (152 µm), drug entrapment efficiency (76%), and cumulative drug release (74.24% within 8 h). These findings are promising for industrial applications and align with the objectives outlined in UN Sustainable Development Goals 3, 9, and 17, as well as the goals of the G20 initiative.

Spectral and HPLC Analyses of Synthesized Butin and Butein.

Butin and butein are significant bioactive flavanones derived from plants, existing as tautomers of each other. However, their physicochemical attributes, such as their spectral profiles under varying experimental conditions in aqueous solutions and established chromatographic methods for distinguishing between them, remain undetermined. In this study, we determined the basic properties of butin and butein using conventional spectroscopic, reversed-phase, and chiral HPLC analyses. The spectra of the synthesized butin and butein were analyzed using a UV-Vis spectrophotometer in several solvents with different polarities as well as in aqueous solutions at various pH values. Furthermore, the behavior of the measured spectra was reproduced by calculations to reveal the effects of the solvent and pH on the spectra of butin and butein in organic and aqueous solutions. Subsequently, we assessed the structural stability of butin and butein using reversed-phase HPLC, which revealed that butein is unstable compared with butin in a general culture medium. The synthesized butin was effectively separated into R- and S-isomers with positive and negative Cotton effects, respectively, via HPLC using a chiral column. These findings will aid in uncovering the individual properties of both butin and butein that may have been concealed by their tautomerism and enable the synthesis of S-butin, which is typically challenging and time-consuming to isolate.

HSPiP, Computational, and Thermodynamic Model-Based Optimized Solvents for Subcutaneous Delivery of Tolterodine Tartrate and GastroPlus­Based In Vivo Prediction in Humans: Part II.

In part I, we reported Hansen solubility parameters (HSP, HSPiP program), experimental solubility at varied temperatures for TOTA delivery. Here, we studied dose volume selection, stability, pH, osmolality, dispersion, clarity, and viscosity of the explored combinations (I-VI). Ex vivo permeation and deposition studies were performed to observe relative diffusion rate from the injected site in rat skin. Confocal laser scanning microscopy (CLSM) study was conducted to support ex vivo findings. Moreover, GastroPlus predicted in vivo parameters in humans and the impact of various critical factors on pharmacokinetic parameters (PK). Immediate release product (IR) contained 60% of PEG400 whereas controlled release formulation (CR) contained PEG400 (60%), water (10%) and d-limonene (30%) to deliver 2 mg of TOTA. GastroPlus predicted the plasma drug concentration of weakly basic TOTA as function of pH (from pH 2.0 to 9). The cumulative drug permeation and drug deposition were found to be in the order as B-VI˃ C-VI˃A-VI across rat skin. This finding was further supported with CLSM. Moreover, IR and CR were predicted to achieve Cmax of 0.0038 µg/ mL and 0.00023 µg/mL, respectively, after sub-Q delivery. Added limonene in CR extended the plasma drug concentration over period of 12 h as predicted in GastroPlus. Parameters sensitivity analysis (PSA) assessment predicted that sub-Q blood flow rate is the only factor affecting PK parameters in IR formulation whereas this was insignificant for CR. Thus, sub-Q delivery CR would be promising alternative with ease of delivery to children and aged patient.

Sustainable and Biomimetic Methodology for Extraction of High-Value-Added Compounds in Almond Hulls.

Almond trees are the most cultivated nut tree in the world. The production of almonds generates large amounts of by-products, much of which goes unused. Herein, this study aimed to develop a green chemistry approach to identify and extract potentially valuable compounds from almond by-products. Initially, a screening was performed with 10 different Natural Deep Eutectic Solvents (NADESs). The mixture lactic acid/glycerol, with a molar ratio 1:1 (1:50 plant material to NADES (w/v) with 20% v/v of water) was identified as the best extraction solvent for catechin, caffeoylquinic acid, and condensed tannins in almond hulls. Subsequently, a method was optimized by a Design of Experiment (DoE) protocol using a miniaturized extraction technique, Microwave-Assisted Extraction (MAE), in conjunction with the chosen NADESs. The optimal conditions were found to be 70 °C with 15 min irradiation time. The optimal extraction conditions determined by the DoE were confirmed experimentally and compared to methods already established in the literature. With these conditions, the extraction of metabolites was 2.4 times higher, according to the increase in total peak area, than the established literature methods used. Additionally, by applying the multiparameter Analytical Greenness Metric (AGREE) and Green Analytical Process Index (GAPI) metrics, it was possible to conclude that the developed method was greener than the established literature methods as it includes various principles of green analytical chemistry.

Optimizing the Extraction of the Polyphenolic Fraction from Defatted Strawberry Seeds for Tiliroside Isolation Using Accelerated Solvent Extraction Combined with a Box-Behnken Design.

Tiliroside is a natural polyphenolic compound with a wide range of biological activity, and defatted strawberry seeds are its rich source. The goal of this study was to optimize accelerated solvent extraction (ASE) conditions, including temperature, solvent composition, and the number of extraction cycles, using Box-Behnken design to maximize the yield of tiliroside. UPLC-DAD-MS was applied to investigate the polyphenolic composition of the extracts, and preparative liquid chromatography (pLC) was used for isolation. All obtained mathematical models generally showed an increase in the efficiency of isolating polyphenolic compounds with an increase in temperature, ethanol content, and the number of extraction cycles. The optimal established ASE conditions for tiliroside were as follows: a temperature of 65 °C, 63% ethanol in water, and four extraction cycles. This allowed for the obtainment of a tiliroside-rich fraction, and the recovery of isolated tiliroside from plant material reached 243.2 mg from 100 g. Our study showed that ASE ensures the isolation of a tiliroside-rich fraction with high effectiveness. Furthermore, defatted strawberry seeds proved to be a convenient source of tiliroside because the matrix of accompanying components is relatively poor, which facilitates separation.

Characterization of a thermostable protease from Bacillus subtilis BSP strain.

This study used conservative one variable-at-a-time study and statistical surface response methods to increase the yields of an extracellular thermostable protease secreted by a newly identified thermophilic Bacillus subtilis BSP strain. Using conventional optimization techniques, physical parameters in submerged fermentation were adjusted at the shake flask level to reach 184 U/mL. These physicochemical parameters were further optimized by statistical surface response methodology using Box Behnken design, and the protease yield increased to 295 U/mL. The protease was purified and characterized biochemically. Both Ca2+ and Fe2+ increased the activity of the 36 kDa protease enzyme. Based on its strong inhibition by ethylenediaminetetracetate (EDTA), the enzyme was confirmed to be a metalloprotease. The protease was also resistant to various organic solvents (benzene, ethanol, methanol), surfactants (Triton X-100), sodium dodecyl sulfate (SDS), Tween 20, Tween-80 and oxidants hydrogen per oxide (H2O2). Characteristics, such as tolerance to high SDS and H2O2 concentrations, indicate that this protease has potential applications in the pharmaceutical and detergent industries.

Stabilization of Non-Native Folds and Programmable Protein Gelation in Compositionally Designed Deep Eutectic Solvents.

Proteins are adjustable units from which biomaterials with designed properties can be developed. However, non-native folded states with controlled topologies are hardly accessible in aqueous environments, limiting their prospects as building blocks. Here, we demonstrate the ability of a series of anhydrous deep eutectic solvents (DESs) to precisely control the conformational landscape of proteins. We reveal that systematic variations in the chemical composition of binary and ternary DESs dictate the stabilization of a wide range of conformations, that is, compact globular folds, intermediate folding states, or unfolded chains, as well as controlling their collective behavior. Besides, different conformational states can be visited by simply adjusting the composition of ternary DESs, allowing for the refolding of unfolded states and vice versa. Notably, we show that these intermediates can trigger the formation of supramolecular gels, also known as eutectogels, where their mechanical properties correlate to the folding state of the protein. Given the inherent vulnerability of proteins outside the native fold in aqueous environments, our findings highlight DESs as tailorable solvents capable of stabilizing various non-native conformations on demand through solvent design.

Preparative separation of the constituents from Ginkgo biloba L. leaves by a combination of multi-stage solvent extraction and countercurrent chromatography.

In this study, we employed a combination approach for the preparative separation of constituents from Ginkgo biloba L. leaves. It involved multi-stage solvent extractions utilizing two-phase multi-solvent systems and countercurrent chromatography (CCC) separations using three different solvent systems. The n-heptane/ethyl acetate/water (1:1:2, v/v) and n-heptane/ethyl acetate/methanol/water (HepEMWat, 7:3:7:3, v/v) solvent systems were screened out as extraction systems. The polarities of the upper and lower phases in the multi-solvent systems were adjustable, enabling the effectively segmented separation of complex constituents in G. biloba L. The segmented products were subsequently directly utilized as samples and separated using CCC with the solvent systems acetate/n-butanol/water (4:1:5, v/v), HepEMWat (5:5:5:5, v/v), and HepEMWat (9:1:9:1, v/v), respectively. As a result, a total of 11 compounds were successfully isolated and identified from a 2 g methanol extract of G. biloba L through two-stage extraction and three CCC separation processes; among them, nine compounds exhibited high-performance liquid chromatography purity exceeding 85%.

Glycyrrhetinic acid interaction with solvated and free electrons studied by the CIDNP and dissociative electron attachment techniques.

Electron transfer plays a crucial role in living systems, including the generation of reactive oxygen species (ROS). Oxygen acts as the terminal electron acceptor in the respiratory chains of aerobic organisms as well as in some photoinduced processes followed by the formation of ROS. This is why the participation of exogenous antioxidants in electron transfer processes in living systems is of particular interest. In the present study, using chemically induced dynamic nuclear polarization (CIDNP) and dissociative electron attachment (DEA) techniques, we have elucidated the affinity of solvated and free electrons to glycyrrhetinic acid (GA)-the aglicon of glycyrrhizin (the main active component of Licorice root). CIDNP is a powerful instrument to study the mechanisms of electron transfer reactions in solution, but the DEA technique shows its effectiveness in gas phase processes. For CIDNP experiments, the photoionization of the dianion of 5-sulfosalicylic acid (HSSA2-) was used as a model reaction of solvated electron generation. DEA experiments testify that GA molecules are even better electron acceptors than molecular oxygen, at least under gas-phase conditions. In addition, the effect of the solvent on the energetics of the reactants is discussed.

UV-based dynamic control improves the robustness of multicolumn countercurrent solvent gradient purification of oligonucleotides.

Therapeutic oligonucleotides (ONs) have great potential to treat many diseases due to their ability to regulate gene expression. However, the inefficiency of standard purification techniques to separate the target sequence from molecularly similar variants is hindering development of large scale ON manufacturing at a reasonable cost. Multicolumn Countercurrent Solvent Gradient Purification (MCSGP) is a valuable process able to bypass the purity-yield tradeoff typical of single-column operations, and hence to make the ON production more sustainable from both an economic and environmental point of view. However, operating close to the optimum of MCSGP can be challenging, resulting in unstable process performance and in a drift in product quality, especially when running a continuous process for extended periods where process parameters such as temperature are prone to variation. In this work, we demonstrate how greater process robustness is introduced in the design and execution of MCSGP for the purification of a 20mer single-stranded DNA sequence through the implementation of UV-based dynamic control. With this novel approach, the cyclic steady state was reached already in the third cycle and disturbances coming from fluctuations in the feed quality, loading amount and temperature were effectively compensated allowing a stable operation close to the optimum. In response to the perturbations, the controlled process kept the standard deviation on product recovery below 3.4%, while for the non-controlled process it increased up to 27.5%.

Dependency of fentanyl analogue protomer ratios on solvent conditions as measured by ion mobility-mass spectrometry.

Recently, our group has shown that fentanyl and many of its analogues form prototropic isomers ("protomers") during electrospray ionization. These different protomers can be resolved using ion mobility spectrometry and annotated using mobility-aligned tandem mass spectrometry fragmentation. However, their formation and the extent to which experimental variables contribute to their relative ratio remain poorly understood. In the present study, we systematically investigated the effects of mixtures of common chromatographic solvents (water, methanol, and acetonitrile) and pH on the ratio of previously observed protomers for 23 fentanyl analogues. Interestingly, these ratios (N-piperidine protonation vs. secondary amine/O = protonation) decreased significantly for many analogues (e.g., despropionyl ortho-, meta-, and para-methyl fentanyl), increased significantly for others (e.g., cis-isofentanyl), and remained relatively constant for the others as solvent conditions changed from 100% organic solvent (methanol or acetonitrile) to 100% water. Interestingly, pH also had significant effects on this ratio, causing the change in ratio to switch in many cases. Lastly, increasing conditions to pH ≥ 4.0 also prompted the appearance of new mobility peaks for ortho- and para-methyl acetyl fentanyl, where all previous studies had only showed one single distribution. Because these ratios have promise to be used qualitatively for identification of these (and emerging) fentanyl analogues, understanding how various conditions (i.e., mobile phase selection and/or chromatographic gradient) affect their ratios is critically important to the development of advanced ion mobility and mass spectrometry methodologies to identify fentanyl analogues.

Evaluation of wound healing and anti-inflammatory activity of hydro-alcoholic extract and solvent fractions of the leaves of Clerodendrum myricoides (Lamiaceae) in mice.

BACKGROUND: Wounds significantly affect people's quality of life and the clinical and financial burden of healthcare systems around the world. Many of the current drugs used to treat wounds have problems such as; allergies and drug resistance. Hence, the exploration of new therapeutic agents from natural origin may avert this problem. Clerodendrum myricoides have long been used to treat wounds in Ethiopia. Despite this, nothing has so far been reported about the wound healing and anti-inflammatory activity of C. myricoides. This study aimed to evaluate the wound healing and anti-inflammatory activity of 80% methanol extract and solvent fractions of C. myricoides leaves in mice. METHODS: Leaves of C. myricoides were extracted using the maceration technique. The extract was formulated as 5% and 10% w/w ointments. The wound healing activity of the extract was evaluated using excision, incision, and burn wound models whereas the healing activities of solvent fractions were evaluated using the excision wound model. A carrageenan-induced paw edema model was used for the anti-inflammatory test. RESULTS: In the dermal toxicity test, 2000 mg/kg of 10% extract was found to be safe. In excision and burn wound models, treatment with 10% and 5% extract showed a significant (p<0.001) wound contraction. Solvent fractions of the extract significantly reduced wound contraction. A significant reduction in periods of epithelialization and favorable histopathology changes were shown by extract ointments. In incision wounds, 10% (p<0.001) and 5% (p<0.01) extracts significantly increase skin-breaking strength. After one hour of treatment, 400 mg/kg (p<0.001) and 200 mg/kg (p<0.05) showed significant reduction in paw edema. CONCLUSION: Results of this study indicate that 80% methanol extract and the solvent fraction of the leaves of C. myricoides possess wound-healing and anti-inflammatory activity and support traditional claims.

Hydroethanolic extracts from Bauhinia guianensis: a study on acute toxicity in Zebrafish embryos and adults.

CONTEXT: The botanical species Bauhinia guianensis Aublet (Leguminosae-Cercidoideae) is traditionally used in the Amazon for medicinal purposes. OBJECTIVE: The acute toxicity of the hydroethanolic extracts from B. guianensis leaves and stems (HELBg and HESBg) was evaluated in zebrafish (Danio rerio), with emphasis on the embryonic developmental stage and adult alterations. MATERIALS AND METHODS: Extracts were analyzed on LC-DAD-MS/MS. Zebrafish eggs were inoculated individually with concentrations of HELBg and HESBg (0.25, 0.5, 0.75, 1.0, and 1.5 µg/mL), observed for 96 h. Adult zebrafish were treated with a single oral dose (100, 200, 500, 1000, and 2000 mg/kg) of HELBg and HESBg, observed for 48 h. RESULTS: HELBg and HESBg analysis detected 55 compounds. Both extracts exhibited toxicity, including embryo coagulation at higher doses of HELBg and absence of heartbeats in embryos at all doses of HESBg. Behavioral variations were observed; tissue alterations in adult zebrafish were found at the highest doses, primarily in the liver, intestine, and kidneys because of HELBg and HESBg effects. The LD50 of HESBg was 1717 mg/kg, while HELBg exceeded the limit dose of 2000 mg/kg. CONCLUSIONS: The study on acute toxicity of B. guianensis extracts exhibits significant toxic potential, emphasizing effects on embryonic and adult zebrafish. The results suggest relative safety of the species preparations, encouraging further clinical trials on potential biological activities.

Antioxidant potentials of extracts from different parts of Clinacanthus nutans (Burm. f.) Lindau.

The research aimed to explore the antioxidant potential of extracts from different parts of Clinacanthus nutans growing in Vietnam, a member of the Acanthaceae family. The plant's roots, stem and leaves were extracted using 96% ethanol. The antioxidant actions of these extracts were evaluated by DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) assay on thin-layer plates and 96 well plates. The extract with the most potent activity was applied for distribution extraction with solvents with different polarities, including dichloromethane, ethyl acetate and water. Dry column vacuum chromatography was utilized to obtain the most antioxidant-potent extract fractions. The stem extract had the lowest IC50 value of 6.85µg/mL, showing the most potent antioxidant activity. The ethyl acetate fraction from the stem extract expressed the lowest IC50 value of 9.67µg/mL. Meanwhile, fraction 5, separated from the ethyl acetate fraction of the stem extract, had the lowest IC50 value of 9.89µg/mL. In conclusion, the extracts from different parts of Clinacanthus nutans all expressed antioxidant action at different levels, in which the stem extract, the ethyl acetate fraction and fraction 5 from the ethyl acetate fraction displayed the most effective actions. These findings highlight the promising potential of Clinacanthus nutans in treating oxidative stress-associated diseases, inspiring further research and exploration in this area.

Valorization of Sour Cherry Kernels: Extraction of Polyphenols Using Natural Deep Eutectic Solvents (NADESs).

The objective of this research was to optimize the natural deep eutectic solvent (NADES) extraction process from sour cherry kernels (Prunus cerasus L.). For polyphenol isolation, conventional solid-liquid extraction was employed using different concentrations of ethanol (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 96%), as well as the innovative NADES extraction technique. In the initial phase of the research, a screening of 10 different NADESs was conducted, while extraction was carried out under constant parameters (50 °C, 1:20 w/w, 60 min). NADES 4, composed of lactic acid and glucose in a molar ratio of 5:1, exhibited the highest efficiency in the polyphenol isolation. In the subsequent phase of the research, response surface methodology (RSM) was utilized to optimize the extraction process. Three independent variables, namely temperature, extraction time, and solid-liquid (S/L) ratio, were examined at three different levels. The extracted samples were analyzed for total phenol (TP) and antioxidant activity using the DPPH, ABTS, and FRAP assays. ANOVA and descriptive statistics (R2 and CV) were performed to fit the applied model. According to RSM, the optimal extraction conditions were determined as follows: temperature of 70 °C, extraction time of 161 min, and S/L ratio of 1:25 w/w.

Exploring separation mechanisms and lipophilicity in hydrophilic interaction chromatography conditions by thin-layer chromatography of anesthetics and adjuvant drugs as polar model compounds.

The chromatographic behavior of the selected compounds was studied under conditions of hydrophilic interaction liquid chromatography (HILIC). The effect of mobile phase composition on the retention in different chromatographic systems was systematically examined using high-performance thin-layer chromatography. The sorbents of different polarity and adsorption characteristics were selected and mixtures of water and organic solvents of various compositions, from pure water to pure organic solvent were used as mobile phases. Increasing the amount of water in the mobile phase leads to a conversion of the separation mechanism, and the retention curves have a characteristic "U" shape. The conversion between the adsorption and partition mechanisms is most likely continuous and depends on the chemical nature of separated substances, the stationary phase as well as on organic component of the mobile phase. Silica gel can be considered the most suitable stationary phase for the systematic investigation of the chromatographic behavior of the test compounds, whereas acetonitrile was the most suitable solvent. The obtained results contribute to the understanding of the dominant separation mechanism, the type, and the intensity of the interactions between separated substances with both stationary and mobile phases. Besides, the lipophilicity parameters obtained under HILIC conditions were evaluated and correlated with the calculated values.

Comparative bioactivity assessment of bixin pigment and associated phytochemicals extracted from annatto seeds using conventional and green solvents.

Nutraceuticals, that include food ingredients and bioactives from natural products, confer physiological health benefits and protection against chronic diseases. Annatto is a tropical shrub grown in Central and South America and parts of India. Its seeds are rich in the edible carotenoid-derived apocarotenoid pigment, bixin, which is used as a natural colorant in food, textiles, and cosmetics, and is now gaining attention for its potential health-promoting attributes. Here, we compared a green solvent (ethyl lactate) based extraction of bixin and associated metabolites in annatto seeds (crushed and seed coat) with two other conventional solvents (acetone and acid-base). Bixin was characterized in the extracts using UV-visible- and FTIR-spectroscopy and thin-layer chromatography. The bixin-containing solvent extracts were then profiled for other co-existing metabolites using GC-MS analysis, which were found to be sesquiterpenes, terpenes, terpenoids, phytosterols, and tocotrienols. Their bioactivity was evaluated based on antioxidant and wound-healing efficacies and compared with pure bixin, using NIH-3T3 fibroblast cells in-vitro. Pure bixin, as well as the annatto solvent extracts, showed strong antioxidant and wound healing properties, wherein pure bixin and green solvent extract (ethyl lactate coat) exhibited higher levels of antioxidant activity, achieving 46.00% and 44.60% reduction in MDA levels, respectively, as well as enhanced wound-healing activity, with 54.09% and 53.60% wound closure within 24 h. The green solvent extracts of annatto seeds revealed: (a) differential bioactive profiles in annatto seeds (crushed and seed coat) in comparison with other solvents, and (b) strong antioxidant and wound healing properties. Thus, ethyl lactate extraction shows strong potential for sustainable environmental friendly production of functional foods/nutraceuticals from annatto seeds.

Solvent concentration at 50% protein unfolding may reform enzyme stability ranking and process window identification.

As water miscible organic co-solvents are often required for enzyme reactions to improve e.g., the solubility of the substrate in the aqueous medium, an enzyme is required which displays high stability in the presence of this co-solvent. Consequently, it is of utmost importance to identify the most suitable enzyme or the appropriate reaction conditions. Until now, the melting temperature is used in general as a measure for stability of enzymes. The experiments here show, that the melting temperature does not correlate to the activity observed in the presence of the solvent. As an alternative parameter, the concentration of the co-solvent at the point of 50% protein unfolding at a specific temperature T in short c U 50 T is introduced. Analyzing a set of ene reductases, c U 50 T is shown to indicate the concentration of the co-solvent where also the activity of the enzyme drops fastest. Comparing possible rankings of enzymes according to melting temperature and c U 50 T reveals a clearly diverging outcome also depending on the specific solvent used. Additionally, plots of c U 50 versus temperature enable a fast identification of possible reaction windows to deduce tolerated solvent concentrations and temperature.