Free Aglycones Research Articles

Optimization of Polyphenol Extraction Conditions from Rhizomes of Curcuma zedoaria with Antioxidant, Anti-Inflammatory and Anti-Diabetic Activities In Vitro

The recovery of polyphenol compounds is seen as an arduous task because polyphenol compounds are available as free aglycones, as sugar or ester conjugates, or as polymers with several monomeric components. The response surface method (RSM) as a tool to optimize the factors that affect extraction efficacy as well as to obtain maximum recovery of the compounds of interest. This study optimizes ultrasound-assisted polyphenol extraction from Curcuma zedoaria rhizomes using response surface methodology (RSM). Three variables were considered: Ethanol concentration (70 - 90 %, v/v), temperature (60 - 80 °C), and ultrasound time (15 - 25 min). Data were analyzed by ANOVA, yielding an R2 of 0.9993, a significant interaction effect (p < 0.0001), and an insignificant lack-of-fit test (p = 0.6684). Optimal conditions for maximum polyphenol content (TPC = 31.05 ± 0.53 mg GAE/g powder) were 80.02 % ethanol, 68 °C, 20.47 min ultrasound time, and 1/10 (w/v) raw material/solvent ratio. Experimental values matched RSM predictions, confirming successful extraction optimization from Curcuma zedoaria rhizomes. The polyphenol-rich optimum extract from Curcuma zedoaria rhizomes has been studied for its antioxidant, anti-inflammatory and anti-inflammatory properties in vitro. The results were found, the optimum extract of Curcuma zedoaria rhizomes could perform effective neutralization activities of free radicals performed in DPPH test (IC50 = 5.89 ± 0.23 µg/mL), NO· (IC50 = 5.89 ± 0.23 µg/mL) and ABTS·+ (IC50 = 8.28 ± 0.12 µg/mL). Besides, this optimum extract had the ability to protect red blood cell membranes and inhibit protein denaturation due to heat with IC50 times values ​​such as 29.06 ± 0.35 and 30.24 ± 0.32 µg/mL. In addition, it also significantly inhibited α-amylase, α-glucosidase enzyme activities with IC50 values ​​of 5.89 ± 0.23 and 9.62 ± 0.11 μg/mL, respectively. This investigation showed that the polyphenol-rich optimum extract from Curcuma zedoaria rhizomes was a promising antioxidant, anti-inflammatory and anti-diabetic agent. HIGHLIGHTS Using ultrasound and the Box-Behnken design to extract polyphenols from Curcuma zedoaria rhizomes can speed up and improve extraction efficiency. The goal of this study is to maximize the extraction parameters for polyphenols from the rhizomes of Curcuma zedoaria. There is strong agreement between the experimental data and the model that predicts the polyphenol content in the Box-Behnken design. In vitro biological activities such as anti-inflammatory, antidiabetic and antioxidant properties are significantly correlated with polyphenol concentration. The findings of our investigation show a noteworthy enhancement in the bioavailability of polyphenol compounds through increased extraction efficiency and bioactivity. GRAPHICAL ABSTRACT

Lacticaseibacillus paracasei JM053 alleviates osteoporosis in rats by increasing the content of soy isoflavone aglycones in fermented soymilk

Lacticaseibacillus paracasei JM053 has a high ability to convert soy isoflavones and can be used as a fermentation strain to ferment soymilk, thereby increasing the content of free aglycones in...

Molecular docking analysis of natural unusual triterpenoids towards PAK1 protein

Triterpenoids are secondary metabolites produced by different natural sources and present in natural sources in the form of free acid or aglycones for triterpenoid saponins in nature. Stellettin B, rhabdaprovidine B, and neviotine A are unusual triterpenoids with their unique skeletal backbone. The serine/threonine p21-activating PAK kinases which play an important pivotal role in intracellular signaling pathways as mediator and join the biochemical process in a cell, such as cytoskeleton dynamics, in cell adhesion, polarity, motility, migration, proliferation, apoptosis, cell division, and in vesicle-mediated transport processes. In this study, molecular docking technique was used for detecting free binding of energy and inhibition constant values of selected triterpenoids towards PAK1 protein. Results showed that that ligand 1 (stellettin B) significantly inhibited the PAK1 enzyme at the value of -8.69 kcal/mol.

Interaction of Quercetin, Cyanidin, and Their O-Glucosides with Planar Lipid Models: Implications for Their Biological Effects.

Flavonoids are specialized metabolites produced by plants, as free aglycones or as glycosylated derivatives, which are particularly endowed with a variety of beneficial health properties. The antioxidant, anti-inflammatory, antimicrobial, anticancer, antifungal, antiviral, anti-Alzheimer's, anti-obesity, antidiabetic, and antihypertensive effects of flavonoids are now known. These bioactive phytochemicals have been shown to act on different molecular targets in cells including the plasma membrane. Due to their polyhydroxylated structure, lipophilicity, and planar conformation, they can either bind at the bilayer interface or interact with the hydrophobic fatty acid tails of the membrane. The interaction of quercetin, cyanidin, and their O-glucosides with planar lipid membranes (PLMs) similar in composition to those of the intestine was monitored using an electrophysiological approach. The obtained results show that the tested flavonoids interact with PLM and form conductive units. The modality of interaction with the lipids of the bilayer and the alteration of the biophysical parameters of PLMs induced by the tested substances provided information on their location in the membrane, helping to elucidate the mechanism of action which underlies some pharmacological properties of flavonoids. To our knowledge, the interaction of quercetin, cyanidin, and their O-glucosides with PLM surrogates of the intestinal membrane has never been previously monitored.

GC/MS Based Metabolite Profiling and Biological Activity of Leaves and Flower Heads of Tanacetum Cinerariifolium (Trevir.) Sch.Bip.

Abstract Flower heads and leaves of Tanacetum cinerariifolium (Trevir.) Sch. Bip. were examined separately for bioactive compounds and biological activity. The compounds were identified by GC/MS analysis. Studied extracts were evaluated for free radical scavenging activity, and for inhibition of acetylcholinesterase and seed germination. Free phenolic acids and flavonoid aglycones were found in larger quantities in the leaves than in the flower heads, where sterols, fatty acids, pyrethrins, sugars, sugar derivatives and bound phenolic acids predominated. Significant antiradical activity (IC50 /mL) and low acetylcholinesterase inhibitory activity (IC50 >1 mg/mL) was found. Moderate inhibitory activity against germination and root elongation of Lolium perenne L. seeds was determined. The study presents for the first time detailed data on the content of phenolic acids in free, esterified and insoluble-bound forms in this species. Some of the identified flavonoids from the leaf extract are reported for the first time in the species. Keywords: GC/MS, Flavonoids, Phenolic acids, Asteraceae (Composite)

Hypoglycemic, analgesic and anti-inflammatory effects of Pulicaria incisa (Lam.) DC extracts in animal models

Purpose: To investigate acute toxicity, hypoglycaemic, analgesic and anti-inflammatory activities of Pulicaria incisa (Lam.) DC.Methods: Acute toxicity analysis was assessed by adopting the OECD - 423 Guidelines. The hypoglycemic effect of P. incisa infusion was investigated utilizing Oral Glucose Tolerance Test (OGTT) on orally glucose-induced hyperglycemic rats. The analgesic effect was investigated using the writhing test model, and anti-inflammatory activity was ascertained by carrageenan-induced paw oedema method.Results: The results showed that half-maximal lethal dose (LD50) values in mice were higher than 14 g/kg. The results of OGTT showed that the plant infusion produced a significant (p < 0.05) reduction in the glucose level in the blood post oral glucose administration. Treatments with diethyl ether, n-butanol and free aglycone extracts at 400 mg/kg significantly reduced (p < 0.05) the abdominal cramps by 82.45, 74.36 and 65.35, % respectively. Diethyl ether extract also showed higher inflammatory inhibition (67 %) than standard (54 %). As predicted, these extracts were less effective against pain and acute inflammation at 800 mg/kg. The HPLC profile demonstrated the existence of phenolic acids, flavones and C-glycosides.Conclusion: The findings show that P. incisa has promising hypoglycemic, analgesic and antiinflammatory effects, which confirms its folkloric medicinal use in Algeria.

Influences of Solubility and Vehicle Carriers on Eriodictyol Pharmacokinetics in Rats.

In this study, the pharmacokinetics of oral doses of eriodictyol in 1% sodium carboxymethylcellulose and in saline/PEG400/Tween80 (75/20/5, v/v/v) in rats were compared. The pharmacokinetics of eriocitrin administered as a dissolved solution in water were also characterized. Metabolites of eriodictyol and eriocitrin in whole blood consisted mainly of eriodictyol, homoeriodictyol, and hesperetin glucuronides and ring-fission metabolites. In whole blood, no free nonconjugated flavanone aglycones were detected. Significant differences were observed in the pharmacokinetics of eriodictyol administered as a suspension in 1% sodium carboxymethylcellulose versus administration as a dissolved solution in saline/PEG400/Tween80 (75/20/5, v/v/v). At a dose of 25 mg kg-1 eriodictyol administered with 1% sodium carboxymethylcellulose, a biphasic pharmacokinetic curve was observed, while only a single concentration peak was observed following an administration of 25 mg kg-1 eriodictyol dissolved in saline/PEG400/Tween80 (75/20/5, v/v/v). For all trials, the pharmacokinetics of eriodictyol differed from those of eriocitrin dissolved in water.

Liquid Chromatographic/Mass Spectrometric Study on the Role of Beech (Fagus sylvatica L.) Wood Polyphenols in Red Heartwood Formation

The present research focused on the analysis of European beech (Fagus sylvatica L.) wood polyphenols in respect to red heartwood formation, which is a significant color and technological defect of the species. For the first time, high-performance liquid chromatography/tandem mass spectrometry and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) were applied for the investigation of the structure and the radial distribution of polyphenols. Altogether 125 compounds were characterized by their MSn spectra, of which 71 were tentatively identified, including procyanidins (dimers to pentamers), flavonoids (taxifolin, naringenin, isorhamnetin, (epi)afzelechin), (+)-catechin, (−)-epicatechin) and their glycoside conjugates, phenolic acids (gallic acid, vanillic acid, syringic acid) and their glycosides as well as gallic acid derivatives, many of which were identified for the first time in beech wood. It was found that the concentration of many compounds increased at the color boundary. In situ polyphenol synthesis and metabolism were clearly evidenced at the color boundary. Red heartwood contained only free aglycones (syringic acid, taxifolin, naringenin, isorhamnetin, naringenin, syringic acid). Contrary to earlier assumptions, the MALDI-TOF analysis did not indicate the presence of oxidized high-molecular-weight polymeric polyphenols in the red heartwood tissues. The role of individual compounds in the formation of the red heartwood chromophores are discussed.

In vitro stability and ex vivo absorption of thymol monoglucosides in the porcine gut

Thymol α-D-glucopyranoside (TαG) and thymol β-D-glucopyranoside (TβG) are believed to have different kinetic behaviours in the porcine gut than its parent aglycon thymol. However, recently, it was shown that concentrations of both glucosides decreased rapidly in the stomach and proximal small intestine following oral supplementation to piglets as did thymol. Yet, the stability of thymol glucosides in gut contents and their absorption route remains obscure. Therefore, a series of in vitro incubations were performed, simulating the impact of pH, digestive enzymes, bacterial activity and mucosal extracts on stability of these glucosides. Their absorption mechanisms were investigated using the Ussing chamber model in the presence or the absence of inhibitors of sodium-dependent glucose linked transporter 1 and lactase phlorizin hydrolase. Both glucosides remained intact at physiological pH levels in the presence of digestive enzymes. Recoveries from TαG and TβG were below 90% when incubated with small intestinal homogenates from the distal jejunum or from all sampled sites, respectively. However, no aglycon could be detected in these samples. Bacterial inoculum of the small intestine, on the other hand, hydrolysed TβG quickly with up to 44% of free aglycon appearing. TαG proved more resistant to porcine gastro-intestinal bacterial glucosidases with only trace amounts (<1%) of free thymol at the end of the incubations. Electrophysiological measurements in Ussing chambers did not suggest active transport of the glucosides. Mucosal TαG and TβG concentrations were unchanged between start and end of the absorption measurements. Additionally, no TαG and only a very limited amount of TβG were retrieved from the serosal side. Tissue associated concentrations, although marginal (<1% of luminal concentration), were mainly as intact glucoside or as aglycon for TαG and TβG, respectively. Addition of both inhibitors significantly increased the amount of intact glucosides retrieved from the mucosal tissues as compared to controls. In conclusion, bacterial hydrolysis was identified as the most important source of TβG loss, whereas TαG seemed less prone to degradation or absorption in these in vitro and ex vivo models.

Untargeted Analysis of Lemna minor Metabolites: Workflow and Prioritization Strategy Comparing Highly Confident Features between Different Mass Spectrometers.

Metabolomics approaches provide a vast array of analytical datasets, which require a comprehensive analytical, statistical, and biochemical workflow to reveal changes in metabolic profiles. The biological interpretation of mass spectrometric metabolomics results is still obstructed by the reliable identification of the metabolites as well as annotation and/or classification. In this work, the whole Lemna minor (common duckweed) was extracted using various solvents and analyzed utilizing polarity-extended liquid chromatography (reversed-phase liquid chromatography (RPLC)-hydrophilic interaction liquid chromatography (HILIC)) connected to two time-of-flight (TOF) mass spectrometer types, individually. This study (introduces and) discusses three relevant topics for the untargeted workflow: (1) A comparison study of metabolome samples was performed with an untargeted data handling workflow in two different labs with two different mass spectrometers using the same plant material type. (2) A statistical procedure was observed prioritizing significant detected features (dependent and independent of the mass spectrometer using the predictive methodology Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA). (3) Relevant features were transferred to a prioritization tool (the FOR-IDENT platform (FI)) and were compared with the implemented compound database PLANT-IDENT (PI). This compound database is filled with relevant compounds of the Lemnaceae, Poaceae, Brassicaceae, and Nymphaceae families according to analytical criteria such as retention time (polarity and LogD (pH 7)) and accurate mass (empirical formula). Thus, an untargeted analysis was performed using the new tool as a prioritization and identification source for a hidden-target screening strategy. Consequently, forty-two compounds (amino acids, vitamins, flavonoids) could be recognized and subsequently validated in Lemna metabolic profile using reference standards. The class of flavonoids includes free aglycons and their glycosides. Further, according to our knowledge, the validated flavonoids robinetin and norwogonin were for the first time identified in the Lemna minor extracts.

Optimization of extraction conditions for polyphenols from the stem bark of Funtumia elastica (Funtum) utilizing response surface methodology.

The recovery of phenolic compounds is seen as an arduous task because phenolic compounds are available as free aglycones, as sugar or ester conjugates, or as polymers with several monomeric components. This study looks at the optimization of factors that affect the efficiency for the extraction of phenolic compounds from the stem-bark of Funtumia elastica. Five independent variables (solvent concentration, time, the temperature, solid-liquid ratio, and pH) of the extraction process were selected. Single factor analysis as well as the response surface method was used to evaluate the impact of the selected factors on the total phenolic content. The effect of the extraction factors on the phenolic content was tested for its statistical significant (p <0.05). For the response surface method, a five/factor, five/level central composite design was used, and a fitted second-order polynomial regression model equation was used to show how the extraction parameters affected the total phenolic recovery. The predicted value (R² of 0.5917) agreed with the adjusted value (R² of 0.7707). The residuals for response predictions were less than 5%. The optimal factors for the extraction were ethanol concentration of 75.99% v/v, extraction time of 193.86 minutes, temperature of 63.66°C, pH of 5.62, and solid-liquid ratio of 1:21.12 g/mL. Actual overall content of the phenolic compounds was validated at 82.83 ± 3.335 mg gallic acid equivalent (GAE) /g weight of extract, which agreed with the predicted response of 89.467 mg GAE/g of the dried extract under the optimal factors. The rich phenolic content of stem-bark of Funtumia elastica points to its potential as a functional medicinal product to alleviate diseases caused by oxidative stress such as asthma, breathing disorders, inflammation, and cardiovascular diseases. The results obtained indicate that, the studied optimal conditions support effective phenolics extraction of Funtumia elastica.

Identification of Flavonoids in the Leaves of Eranthis longistipitata (Ranunculaceae) by Liquid Chromatography with High-Resolution Mass Spectrometry (LC-HRMS)

Eranthis longistipitata Regel is an endemic plant of Central Asia. The flavonoid profile of E. longistipitata leaves was studied by mass spectrometry for the first time (natural populations of Kyrgyzstan and Uzbekistan, in 70% aqueous–ethanol extracts by liquid chromatography coupled with high-resolution mass spectrometry). Mass spectrometry revealed 18 flavonoid compounds. Flavonols featured the highest diversity, and 10 such substances were identified: 2 free aglycones (quercetin and kaempferol), 6 quercetin glycosides (peltatoside, hyperoside, reynoutrin, quercetin 3-sambubioside, rutin, and isoquercitrin), and 2 kaempferol glycosides (juglalin and trifolin). Two flavans (cianidanol and auriculoside), two hydroxyflavanones (6-methoxytaxifolin and aromadendrin), and one C-glycoside flavone—carlinoside—were identified. Dihydroxychalcones aspalathin, phloridzin, and phloretin were found too. Levels of rutin, quercetin, kaempferol, and hyperoside were confirmed by means of standards and high-performance liquid chromatography. Rutin concentration was the highest among all other identified flavonoid compounds: in the leaf samples from Kyrgyzstan, it ranged from 2.46 to 3.20 mg/g, and in those from Uzbekistan, from 1.50 to 3.01 mg/g. The diversity of flavonoid compounds in E. longistipitata leaves is probably due to external ecological and geographic factors and adaptive mechanisms.

A review of the techniques for mitigating the effects of smoke taint in wine production

Smoke taint has become a prominent issue for the global wine industry as climate change continues to impact the length and extremity of fire seasons around the world. When grapevines are exposed to smoke, their leaves and fruit can adsorb volatile smoke compounds (for example, volatile phenols such as guaiacol, 4-methylguaiacol, o-, m- and p-cresol, and syringol), which can initially be detected in free (aglycone) forms but are rapidly converted to glycoconjugate forms due to glycosylation. During the fermentation process, these glycoconjugates can be broken down, releasing volatile phenols that contribute undesirable sensory characteristics to the resultant wine (i.e. smokey and ashy attributes). Several methods have been evaluated, both viticultural measures and winemaking techniques, for mitigating and/or remediating the negative effects of grapevine smoke exposure. While there is currently no single method that universally solves the problem of smoke taint, this paper outlines the tools available that can help to minimize the negative impacts of smoke taint (Figure 1).

Optimization of extraction conditions for polyphenols from the stem bark of Funtumia elastica (Funtum) utilizing response surface methodology

Background: The recovery of phenolic compounds is seen as an arduous task because phenolic compounds are available as free aglycones, as sugar or ester conjugates, or as polymers with several monomeric components. This study looks at the optimization of factors that affect the efficiency for the extraction of phenolic compounds from the stem-bark of Funtumia elastica. Methods: Five independent variables (solvent concentration, time, the temperature, solid-liquid ratio, and pH) of the extraction process were selected. Single factor analysis as well as the response surface method was used to evaluate the impact of the selected factors on the total phenolic content. The effect of the extraction factors on the phenolic content was tested for its statistical significant (p <0.05). For the response surface method, a five/factor, five/level central composite design was used, and a fitted second-order polynomial regression model equation was used to show how the extraction parameters affected the total phenolic recovery. Results: The predicted value (R² of 0.5917) agreed with the adjusted value (R² of 0.7707). The residuals for response predictions were less than 5%. The optimal factors for the extraction were ethanol concentration of 75.99% v/v, extraction time of 193.86 minutes, temperature of 63.66°C, pH of 5.62, and solid-liquid ratio of 1:21.12 g/mL. Actual overall content of the phenolic compounds was validated at 82.83 ± 3.335 mg gallic acid equivalent (GAE) /g weight of extract, which agreed with the predicted response of 89.467 mg GAE/g of the dried extract under the optimal factors. Conclusions: The rich phenolic content of stem-bark of Funtumia elastica points to its potential as a functional medicinal product to alleviate diseases caused by oxidative stress such as asthma, breathing disorders, inflammation, and cardiovascular diseases. The results obtained indicate that, the studied optimal conditions support effective phenolics extraction of Funtumia elastica.

Kaempferol-3-O-α-(3,4-di-E-p-coumaroyl)-rhamnopyranoside from Nectandra oppositifolia releases Ca2+ from intracellular pools of Trypanosoma cruzi affecting the bioenergetics system

Phytochemical analysis of EtOH extract from leaves of Nectandra oppositifolia afforded three flavonoids: kaempferol (1), kaempferol-3-O-α-rhamnopyranoside (2) and kaempferol-3-O-α-(3,4-di-E-p-coumaroyl)-rhamnopyranoside (3), which were characterized by NMR and ESI-HRMS. When tested against the protozoan parasite Trypanosoma cruzi, the etiologic agent of Chagas disease, flavonoids 1 and 3 were effective to kill the trypomastigotes with IC50 values of 32.0 and 6.7 μM, respectively, while flavonoid 2 was inactive. Isolated flavonoids 1–3 were also tested in mammalian fibroblasts and showed CC50 values of 24.8, 48.7 and 153.1 μM, respectively. Chemically, these results suggested that the free aglycone plays an important role in the bioactivity while the presence of p-coumaroyl unities linked in the rhamnoside unity is important to enhance the antitrypanosomal activity and reduce the mammalian cytotoxicity. The mechanism of cellular death was investigated for the most potent flavonoid 3 in the trypomastigotes using fluorescent and luminescent-based assays. It indicated that this compound induced neither permeabilization of the plasma membrane nor depolarization of the membrane electric potential. However, early time incubation (20 min) with flavonoid 3 resulted in a constant elevation of the Ca2+ levels inside the parasite. This effect was followed by a mitochondrial imbalance, leading to a hyperpolarization and depolarization of the mitochondrial membrane potential, with reduction of the ATP levels. During this time, the levels of reactive oxygen species levels (ROS) were unaltered. The leakage of Ca2+ from the intracellular pools can affect the bioenergetics system of T. cruzi, leading to the parasite death. Therefore, flavonoid 3 can be a useful tool for future studies against T. cruzi parasites.

Optimization of extraction conditions for polyphenols from the stem bark of Funtumia elastica (Funtum) utilizing response surface methodology.

Background: The recovery of phenolic compounds is seen as an arduous task because phenolic compounds are available as free aglycones, as sugar or ester conjugates, or as polymers with several monomeric components. Furthermore, phenolic compounds do not disperse evenly and may be connected to cell walls, carbohydrates, or proteins. This study looks at the optimization of factors that affect the efficiency for the extraction of phenolic compounds from the stem-bark of Funtumia elastica. Methods: Five independent variables (solvent concentration, time, the temperature, solid-liquid ratio, and pH) of the extraction process were selected. Single factor analysis as well as the response surface method was used to evaluate the impact of the selected factors on the total phenolic content. The effect of the extraction factors on the phenolic content was statistically significant (p <0.05). For the response surface method, a five/factor, five/level central composite design used, and a fitted second-order polynomial regression model equation was used to show how the extraction parameters affected the total phenolic recovery. Results: The predicted value (R² of 0.5917) agreed with the adjusted value (R² of 0.7707). The residuals for response predictions were less than 5%. The optimal factors for the extraction were ethanol concentration of 75.99% v/v, extraction time of 193.86 minutes, temperature of 63.66°C, pH of 5.62, and solid-liquid ratio of 1:21.12 g/mL. Actual overall content of the phenolic compounds was validated at 82.83 ± 3.335 mg gallic acid equivalent (GAE) /g weight of extract, which agreed with the predicted response of 89.467 mg GAE/g of the dried extract under the optimal factors. Conclusions: The rich phenolic content of stem-bark of Funtumia elastica points to its potential as a functional medicinal product to alleviate diseases caused by oxidative stress such as asthma, breathing disorders, inflammation, and cardiovascular diseases.

Chemical diversity analysis and biological activities evaluation of different polyphenolic extracts of Marrubium deserti De Noé from Algeria

Ethnopharmacological relevanceMarrubium deserti De Noé (Lamiaceae) commonly known as desert horehound, is a small perennial herb distributed in arid climates. This plant has been used in Algeria for the treatment of cold, cough, fever and inflammation.Aim of the study: This study aimed to perform a phytochemical analysis and to evaluate the effect of diethyl ether (ExDiEth), n-butanol (ExBut) and hydroalcoholic (ExHyD) extracts of the aerial parts of M. deserti De Noé on inflammation, nociceptive response and fever in animal models. Materials and methodsThe total phenolic content and the different phenolic fraction (flavones-flavonols, free aglycones, anthocyanidins, C-glycosides and flavonic heterosides) were quantified in order to study the chemical diversity. The anti-inflammatory effect was evaluated using carrageenan-induced paw oedema test and the nociceptive response was determined by the chemical method using acetic acid-induced writhing response and formalin-induced paw licking tests and by the thermal method using the hot plate in mice. In addition, anti-fever was investigated using yeast-induced pyrexia in rats. ResultsQuantitative analysis revealed that among all extracts, ExBut had a higher phenolic content and the aerial parts of M. deserti De Noé collected from two different sites (Biskra and Tamanresset) had a significant difference in the contents of flavonic heterosids and flavones-flavonols. PCA and CA showed a strong intra-specific variability of M. deserti De Noé individuals. Our results showed that the ExDiEth, ExBut and ExHyD treatments prevented the increase of paw oedema by 56.25%, 66.65% and 45.56% inhibition percent, respectively. Moreover, treatments with these extracts significantly (p<0.05) decreased the number of writhing and increased the reaction time to thermal stimulation as well as demonstrated reduction in paw licking time both at early and late phases. Likewise, they also showed a significant reduction of yeast-induced pyrexia till 4 h of treatment. ConclusionResults from this study show that M. deserti De Noé aerial parts exhibited anti-inflammatory, analgesic with central and peripheral actions and antipyretic activities which could be associated with the presence of some phytochemicals as flavones, flavonols, flavonic heterosids and phenolic acids.

Elucidation of Endogenous Aroma Compounds in Tamarillo (Solanum betaceum) Using a Molecular Sensory Approach.

Glycosidically bound volatiles (GBVs) are flavorless compounds in fruits and may undergo hydrolysis during fruit maturation, storage, and processing, releasing free aglycones that are odor active. However, the contribution of glycosidic aglycones to the sensory attributes of fruits remains unclear. Herein, the key odor-active aglycones in tamarillo fruits were elucidated through the molecular sensory approach. We extracted GBVs from three cultivars of tamarillo fruits using solid-phase extraction and subsequently prepared aglycone isolates by enzymatic hydrolysis of GBVs. Gas chromatography-mass spectrometry-olfactometry (GC-MS-O) coupled with odor activity value (OAV) calculation, comparative aroma extract dilution analysis (cAEDA), and omission tests were used to identify key aromatic aglycones. A total of 42 odorants were determined by GC-MS-O analysis. Among them, trans-2,cis-6-nonadienal, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF), linalool, 4-vinylguaiacol, geraniol, and α-terpineol showed high OAVs. The cultivar Amber had more aglycones with flavor dilution (FD) factors >16 than the Mulligan cultivar (27 vs 21, respectively), and the Laird's Large fruit showed the highest FD of 1024 for glycosidic DMHF. Omission tests indicated 14 aglycones as essential odorants related to GBVs in tamarillo fruits. Moreover, the enzymatic liberation of aglycones affected the sensory attributes of the tamarillo juice, resulting in an intensified odor profile with noticeable fruity and sweet notes. This study gives insights into the role of endogenous aroma during tamarillo-flavor perception, which lays the groundwork for developing tamarillo-based products with improved sensory properties.

The expression of β-glucosidase during natto fermentation increased the active isoflavone content

Natto is a traditional food fermented by Bacillus subtilis natto with soybean as raw material and contains a variety of active substances, especially flavonoid. Flavonoids in soybean usually exist in the form of inactive glycosides, which can only play biological activities when being decomposed into free isoflavone aglycone by β-glucosidase. In this study, the relationship between the activity of β-glucosidase, the expression of β-glucosidase coding genes and the content and structure of active isoflavones in Bacillus natto was systematically elucidated for the first time. In this research, more than 70 kinds of flavonoids have been identified and the active isoflavones in natto increased by 2.2 times compared with soybeans. Furthermore, the activity of β-glucosidase and the expression level of its coding genes were both increased, which laid a theoretical foundation for further understanding the active substances and physiological functions of natto and the application of β-glucosidase in food industry.

Characterization of Free and Bound Monoterpene Alcohols during Riesling Fermentation

The isomeric nature of monoterpenyl glycosides makes unambiguous identification of intact glycosides difficult. As a result, it is challenging to relate the changes in free monoterpenol concentrations to the corresponding glycosides during wine fermentation and storage. In this study, we isolated and identified linalool, nerol, and geraniol monoterpenyl glycosides fromVitis viniferacv. Riesling grapes through fractionation followed by acid or enzyme hydrolysis. Changes in the composition of identified monoterpenyl glycosides and their respective free volatiles were then monitored during alcoholic fermentations of Riesling juice with four different yeast strains across two successive years. The relative concentrations of the volatiles were monitored by solid-phase microextraction gas chromatography mass spectrometry, while ultrahigh-performance liquid chromatography quadrupole time-of-flight mass spectrometry was used for intact glycosides. Glycoside hydrolysis during fermentation could be related to relative concentrations of the corresponding free aglycones. However, other sources of free monoterpenols were also observed. Differences in glycoside hydrolysis among yeast strains and across years were observed and may be related to grape maturity and/or nutrient levels.