Solvent Fractions Research Articles

Analgesic and Anti-Inflammatory Effects of 80% Methanol Extract and Solvent Fractions of the Leaves of Vernonia auriculifera Hiern. (Asteraceae).

The leaves of V. auriculiferahas been used traditionally for the treatment of inflammatory disorders, and pain in various parts of Ethiopia. However, to our knowledge, the analgesic and anti-inflammatory activity of the crude extract and solvent fractions has never been experimentally studied. To assess the analgesic and anti-inflammatory activitiesof V. auriculifera leaf extract and solvent fractions in rodent models. Air-dried leaves ofV. auriculiferawere grounded and macerated using 80% methanol. The air-dried, grounded leaves were also successively extracted with ethyl acetate, and methanol. The residue was then macerated in water for 72 hr. The extract's peripheral analgesic activity, as well as the solvent fractions, were determined using an acetic acid-induced writhing test. The hot plate model was used to assess the central analgesic effect. Carrageenan-induced hind paw edema and cotton pellet-induced granuloma models were used to assess the anti-inflammatory effect in rats. The 80% methanol leaf extract and solvent fractions have demonstrated significant (p < 0.05) peripheral and central analgesic activity. Both 80% methanol leaf extract and solvent fractions of V. auriculifera were found to have anti-inflammatory activity in a carrageenan-induced rat paw edema model. In the cotton pellet-induced granuloma model, all concentrations of 80% methanol leaf extract (ME), methanol fraction (MEF), and aqueous fractions (AQF) of V. auriculifera inhibited exudate and granuloma formation. Although all tested doses significantly inhibited granuloma mass formation, only the medium and highest ethyl acetate fraction (EAF) doses significantly inhibited the generation of inflammatory exudate. This study's findings indicate that the solvent fractions and 80% methanol extract of V. auriculifera have analgesic and anti-inflammatory properties. This study's findings not only confirm the plants' traditional claim but also provide clues for further investigation of the active principles of this plant for the development of effective and safe analgesic and anti-inflammatory drugs.

Evaluation of the Antioxidant and Wound Healing Properties of 80% Methanol Extract and Solvent Fractions of the Leaves of Vernonia auriculifera Hiern. (Asteraceae).

The leaves of Vernonia auriculifera (Asteraceae) have traditionally been used to treat wounds in several regions of Ethiopia. The purpose of this study was to assess the wound healing properties of the leaf extract and solvent fractions of V. auriculifera in mice. The leaf extract and solvent fractions of V. auriculifera have also been evaluated for their anti-oxidant properties because of their impact on the wound healing process. Air-dried leaves were extracted using 80% methanol. They were also successively fractionated with n-hexane, ethyl acetate, and methanol. The residue was then macerated in water for 72 hr. Simple ointment bases were formulated according to British Pharmacopoeia. Thereafter, two types of ointment formulations, 2.5% w/w and 5% w/w, were formulated. Wound healing and acute dermal toxicity studies were performed on mice. To assess free radical scavenging activity, a 2,2-diphenyl-2-picrylhydrazyl free radical (DPPH) assay was performed. In both models, wounds treated with 2.5% and 5% (w/w) of the ME, the aqueous fraction (AQF), methanol fraction (MEF), and ethyl acetate fraction (EAF) ointments demonstrated significant wound healing activity, as shown by enhanced wound contraction, a shortened epithelialization time, increased hydroxyproline content, and enhanced tissue breaking strength. The extract and solvent fractions displayed free radical scavenging activity with IC50 values of 1.2 mg/mL, 1.46 mg/mL, 1.5 mg/mL, and 2.83 mg/mL for ME, AQF, MEF, and EAF, respectively, as compared to 1.42 mg/mL for ascorbic acid. The result of this study indicates that 80% of methanol extract and solvent fractions are endowed with wound healing activity. Additionally, this study has also revealed that ME, AQF, MEF, and EAF have the capacity to scavenge free radicals. The study indicated that the wound healing effect could be attributed to the anti-inflammatory and antioxidant activities.

Interfacial activity and Pickering stabilization of kraft lignin particles obtained by solvent fractionation

Upgrading lignin particles with controlled morphology and amphiphilicity to investigate the stabilization mechanism in Pickering systems is reported.

In Vivo Hypolipidemic, Hypoglycemic, Antihyperglycemic, and In Vitro Antioxidant Effects of Podocarpus gracilis Leaf Extract and Fractions in Diabetic Mice.

Podocarpus gracilis is an evergreen, dioecious tree found in Ethiopia and other African nations. It can reach a height of 60 meters. Without any scientific validation, ethnobotanical studies conducted in Ethiopia revealed that the Podocarpus gracilis plant's leaf is consumed orally to treat diabetes mellitus. Hence, this study aims to evaluate the in vivo blood glucose level lowering, lipid-lowering, and in vitro-free radical scavenging responses of Podocarpus gracilis leaf extract and fractions on experimental mice induced with diabetes. The in vitro antioxidant activity of PGC (Podocarpus gracilis) leaf extract was assessed by using a diphenyl-2-picrylhydrazyl (DPPH) assay. The oral glucose-loaded, normoglycemic, and streptozotocin- (STZ-) induced diabetic mouse models were employed. In the STZ-induced mice model, the leaf extract and solvent fractions activity on serum lipid and weight were also measured. The extract and fractions were tested at 100, 200, and 400 mg/kg dosages. One-way ANOVA was used to determine the statistical significance of BGL (blood glucose level) changes within and between groups, and Tukey's post hoc multiple comparisons were then performed. In the acute toxicity study of Podocarpus gracilis leaf extract and fractions, there was no evidence of animal mortality at the maximum dose of 2 g/kg during the observation period. The extract-treated group with normoglycemia revealed a significant lowering in BGL at the 4-hour mark of 27.4% (p < 0.001) and 25.2% (p < 0.01) at doses of 200 mg/kg and 400 mg/kg, respectively, compared to that in negative control. In the oral glucose tolerance test (OGTT) model, only 400 mg/kg treated groups at 120 min after exposure showed a BGL reduction of 31.17% which was statistically significant (p < 0.05) in comparison to the negative control. In the single-dose STZ-induced model, eighth-hour BGL measurements from CE 100, CE 200, CE 400, and GLC5 showed drops in BGL of 43.1%, 44.1%, 45%, and 47.3% from baseline fasting BGL values. In the repeated streptozotocin (STZ)-induced model, at all doses of leaf extract and fractions, the fasting BGL was significantly (p < 0.001) reduced. Moreover, the leaf extract and solvent fractions have shown a significant (p < 0.001) reduction of serum lipids such as LDL, TC, and VLDL, and at the same time, it increases HDL at 14 days with body weight gained. In the test for antioxidant activity, the half-maximal inhibitory concentrations (IC50) for leaf extract and the standard medication (ascorbic acid) were 8.2 μg/ml and 3.3 μg/ml, respectively. The IC50 value denotes the concentration of the sample required to scavenge 50% DPPH radicals. The 80% hydromethanolic leaf extract and fractions of Podocarpus gracilis exhibited blood glucose lowering, lipid-lowering activity in normoglycemic, oral glucose tolerance test (OGTT) mode, and STZ-induced diabetic mice with weight gains. There is scientific support for the alleged traditional use as an antidiabetic, lipid-lowering, and antioxidant activity. The results need to be confirmed by future studies.

SELECTED TRADITIONAL MEDICINAL PLANTS TO REDUCE POST-PRANDIAL HYPERGLYCAEMIA: AN IN VITRO SCREENING

The present study is focussed on an in vitro approach to evaluate the antidiabetic potential of some selected traditional medicinal plants used by traditional practitioners of South India for curing hyperglycaemia. The study emphasized on the potential of the extracts to reduce post-prandial glucose levels through inhibition of carbohydrate hydrolyzing enzyme, α-amylase and its mode of inhibition. Four different solvent fractions (Petroleum ether fraction, Chloroform fraction, Ethyl acetate fraction and 80% methanolic fraction) of extracts of shoots of Tinospora crispa (L) Hook.f. and Thomson, denoted as PE TC, CH TC, EA TC, 80%M TC and roots of Anacardium occidentale L, denoted as PE AO, CH AO, EA AO and 80%M AO were selected for antidiabetic screening. Phytochemical profiling of the extracts revealed that the all of the eight extracts were a rich repository of secondary metabolites. Ensuing to standard acarbose drug (IC50 value = 0.19 mg/mL), PE TC (IC50 value =1.49 mg/mL) outperformed among the fractions evaluated to exhibit an uncompetitive mode of inhibiting the α-amylase enzyme. 80%M AO, CH AO too exhibited substantial inhibitory activity on the enzyme followed by CH AO that showed a mixed inhibitory response. Remaining fractions remained uncompetitive. All the extracts exhibited potential antioxidant activity, 80% M AO being the best with an IC50 value of 0.026 mg/mL followed by EA AO (IC50 value =0.031 mg/mL). The cytotoxicity assay of the extracts on the MIN6 pancreatic cell lines revealed all the extracts to be least cytotoxic. Thus, PE TC and 80%M AO offers to be promising lead candidates to be developed as an efficient antidiabetic agents for post-prandial hyperglycaemia.

The importance of a good solvent of conjugated polymers for preparing dopant solution on the electrical and mechanical properties of sequentially doped conjugated polymer films

Electrical conductivity σ of the doped P3HT films is plotted against the volume fraction of a good solvent in the doping solvent blend.

Evaluation of the Polarity in Binary Liquid Mixtures as a Function of Volume Fraction

The variation of solvatochromic polarity parameters as a function of mole fraction data may not represent the realistic environment of the solvatochromic probe molecule. This is because of the fact that the solvation environment of the solvatochromic probe molecules is not only determined by the number of individual solvent molecules around it but also by the size of those individual solvent molecules. In this regard we wish to understand the variation of ET N polarity parameter of binary liquid mixtures as a fuction of volume fractions. Representation of the ET N parameter as a function of volume fraction data leads to a completely different dataset for binary liquid mixtures where water is used as one of the solvents. These mixtures usually display negative deviations from linearity for the ET N values, when ET N values are plotted as a function of mole fraction values of the solvents. On the other hand, if the ET N values are plotted as a function of volume fraction values of the solvents in binary liquid mixtures containing water, these deviations are minimized to a large extent and even reversed to the positive deviations in some of these mixtures. This study gives an insight into a long lasting problem of understanding the negative deviations of the ET N values from linearity observed in binary liquid mixtures of water, as these deviations are either minimized or reversed into positive deviations when ET N values are plotted versus volume fraction of solvents. This study opens up a whole new discussion about the solvatochromic data of the solvent mixtures, whether this data must be represented as a function of mole fraction values or as a function of volume fraction of the solvents. The representation of the solvatochromic data as a function of volume fraction of solvents might lead to new insights in studying the solute-solvent interactions in binary solvent mixtures.

Quantitative prediction of the solvent fractionation of lignin

A combined experimental and theoretical framework was developed that predicts the solvent fractionation of lignin, taking chemical and physical dispersity into account. This paves the way for a broader applicability of lignin in bio-based materials.

Evaluation of Wound Healing and Anti-Inflammatory Activities of 80% Methanol Crude Extract and Solvent Fractions of Trichilia dregeana Sond (Meliaceae) Leaves in Mice.

The leaves of Trichilia dregeana Sond are traditionally used to treat wounds. Even though there have been in vitro studies and claims supporting wound healing, there are no scientific data on in vivo wound healing and anti-inflammatory activities of the leaves of T. dregeana. This study aimed to evaluate wound healing and anti-inflammatory activity of 80% methanol crude extract and solvent fractions of T. dregeana in mice. The leaves of T. dregeana were dried, ground, and macerated with 80% methanol three times successively. The crude extract was fractioned by water, ethyl acetate, and hexane separately. The acute dermal and oral toxicity tests were done by applying 2000 mg/kg of 10% (w/w) crude extract ointment (CEO) topically and 2000 mg/kg of crude extract orally, respectively. The wound healing activity of the crude extract was evaluated on excision, incision, and burn wound models while the fractions were evaluated only on excision wound model. The anti-inflammatory activity of the crude extract was evaluated on xylene-induced ear edema and cotton pellet granuloma tests. Both acute dermal and oral toxicity tests were found to be safe after topical application of 2000 mg/kg of 10% (w/w) CEO and oral administration of 2000 mg/kg of crude extract suspension, respectively. Both 5% and 10% (w/w) CEO produced significant (p < 0.001) wound contraction and period of epithelialization from day 4 onwards as compared to simple ointment (SO) on both excision and burn wounds. The tensile strength was increased significantly (p < 0.001) for the CEO-treated mice as compared to both untreated and SO groups. The crude extract also showed anti-inflammatory activity at 100, 200, and 400 mg/kg by inhibiting ear edema, exudate, and granuloma formation as compared to the SO group. The increase in wound contraction, reduction in period of epithelialization, and increase in tensile strength support the traditional claims of T. dregeana for wound healing.

Nitrite scavenging and lipid peroxidation inhibitory effects of solvent fractions from Phragmites communis rhizome extract

Nitrite scavenging and lipid peroxidation inhibitory effects of solvent fractions from <i>Phragmites communis</i> rhizome extract

Toxicological evaluation of different solvent fractions of Waltheria indica linn. root in male wistar rats

Waltheria indica Linn. root (WILR) is a multipurpose medicinal plant with abundance of phytochemical compounds. The optimal solvents for extraction of a particular bioactive compound depends not only on the yield of the compound but also on the toxic effect of the solvent used. Therefore, this study was designed to evaluate the toxic effects of hexane, dichloromethane and ethyl acetate solvent fractions of WILR in male Wistar rats. Three doses (200, 500, or 1000 μg/kg BW) of hexane, dichlorometh ane and ethyl acetate solvent fractions of WILR were used. Male Wistar rats (n=5) were administered with 200, 500, or 1000 μg/kg of hexane, dichloromethane, and ethyl acetate soluble extracts of WILR, while control received distilled water, daily for 15 days. The rats were thereafter sacrificed, blood samples were collected and serum separated. Haematological serum biochemical parameters were determined according to standard procedure. The result showed non-significant effect on relative organ weight and haematological parameters while the serum ALT was significantly increased by administration of hexane, dichloromethane, and ethyl acetate soluble extracts of WILR. Blood Urea Nitrogen was also increased significantly (p &lt; 0.05) at 200 and 500 μg/kg of hexane and dichloromethane respectively. The ethyl acetate and hexane fraction also caused severe periportal cellular infiltration in the liver while the hexane fraction caused glomerular necrosis. The hexane, dichloromethane and ethyl acetate soluble extracts of (WILR) have adverse effect on the integrity liver and kidney. Hence, these extracts should be used with caution in patient with hepatic and renal impairment.

Toxicological evaluation of different solvent fractions of Waltheria indica linn. root in male wistar rats

Waltheria indica Linn. root (WILR) is a multipurpose medicinal plant with abundance of phytochemical compounds. The optimal solvents for extraction of a particular bioactive compound depends not only on the yield of the compound but also on the toxic effect of the solvent used. Therefore, this study was designed to evaluate the toxic effects of hexane, dichloromethane and ethyl acetate solvent fractions of WILR in male Wistar rats. Three doses (200, 500, or 1000 μg/kg BW) of hexane, dichlorometh ane and ethyl acetate solvent fractions of WILR were used. Male Wistar rats (n=5) were administered with 200, 500, or 1000 μg/kg of hexane, dichloromethane, and ethyl acetate soluble extracts of WILR, while control received distilled water, daily for 15 days. The rats were thereafter sacrificed, blood samples were collected and serum separated. Haematological serum biochemical parameters were determined according to standard procedure. The result showed non-significant effect on relative organ weight and haematological parameters while the serum ALT was significantly increased by administration of hexane, dichloromethane, and ethyl acetate soluble extracts of WILR. Blood Urea Nitrogen was also increased significantly (p &lt; 0.05) at 200 and 500 μg/kg of hexane and dichloromethane respectively. The ethyl acetate and hexane fraction also caused severe periportal cellular infiltration in the liver while the hexane fraction caused glomerular necrosis. The hexane, dichloromethane and ethyl acetate soluble extracts of (WILR) have adverse effect on the integrity liver and kidney. Hence, these extracts should be used with caution in patient with hepatic and renal impairment.

Fractionation and Absolute Molecular Weight Determination of Organosolv Lignin and Its Fractions: Analysis by a Novel Acetone-Based SEC─MALS Method

Accurate and reliable structural characterization of technical lignins is still challenging and inhibits industrial utilization as only poor understanding of structure–property relationship is available. Especially, molar mass analysis of technical lignins is of paramount interest; however, the usage of conventional size exclusion chromatography (SEC) and synthetic polymer standards as a consequence of inaccessible lignin standards is predominantly found in academia. This leads to a huge discrepancy in molecular weight analyses of lignins between different laboratories and consequently to fragile comparability. In this study, organosolv (OS) lignin from beech wood was exemplarily used to develop and evaluate a new acetone–water-based SEC method with the ability to be coupled to an electrospray ionization-mass spectrometer (ESI-MS) or to a multi-angle light scattering detector (MALLS or short MALS). The eluent system used shows very good solubility for the lignins investigated and hence lowers the probability for molecular aggregation of lignin molecules in solution. Solvent fractionation in acetone–water mixtures was conducted to acquire molecular weight classes. The starting lignin (parent lignin) was initially dissolved in 80 wt % acetone–water. Various fractions of the parent lignin were produced by a stepwise reduction of the acetone content. Molecular weights based on narrow polyethylene glycol (PEG)/polyethylene oxide (PEO) standards and absolute molar masses by coupling SEC with MALS were obtained, and the drawback of using polymer standards is discussed in detail. At a lower acetone content, low-molecular-weight fractions were found. Additionally, the specific refractive index increments (dn/dc) were determined for the parent lignin and its fractions. The impact of dn/dc on the final molecular weight (MW) was evaluated considering the chemical composition obtained by nuclear magnetic resonance spectroscopy (NMR) analysis. Furthermore, light scattering revealed that the absorption behavior for this OS lignin is low and neglectable. This article proposes a new acetone-based analytical method for direct determination of absolute molar masses of OS lignin molecules.

Phenolic, Flavonoids Content, Antioxidant Potential of Murraya koenigii L. (Curry Leave): in vitro and in vivo Protective Effects

In the current investigation, the proximate value, total phenolic content, toal flavonoid content, antioxidant potential and in vitro and in vivo protective effects of Murraya koenigii L. (curry leave) extracts were carried out. Flavonoids, phenols and alkaloids were recorded in ethanol, methanol, ethyl acetate, petroleum ether, benzene and acetone extracts. A higher level of total phenolic content was recorded in ethanolic fraction followed by benzene, ethyl acetate, methanol, petroleum ether and acetone fractions. The total flavonoids content was recorded in the range of 5.12 mg RE g−1 to 9.24 mg RE g−1. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity was estimated in all the solvent fractions at the concentration ranging from 312.5 μg mL-1 to 5000 μg mL−1. Percentage inhibition was recorded in the range of 39.40 to 72.32. To study the antimutagenic property, the plate incorporation method was used to see the effects of the MKLE fraction on S. typhimurium trains TA 1537, TA 1535, TA 98, TA 100 and TA 102 both in the absence and presence of S9 mix (5% v/v). Higher antimutagenic property at a concentration of 5000 μg/plate with 2-nitrofluorene 7.5 μg/plate was observed against TA 98. In vivo study indicates the protective effects of the extract of the MKLE against chlorpyrifos-induced toxicity in brain and lungs of the experimental rats. Four animal groups 5 male and 5 females were selected, group I serve as a control, group II was given a single dose of MKLE as such for 28 consecutive days while group III was treated with chlorpyrifos at the dose level of 60 mg/kg B.wt and group IV was dosed with chlorpyrifos at the dose level of 60 mg/kg B.wt simultaneously treated with the MKLE as such twice in a day (B.D.). Chlorpyrifos administration (group III) to the rats resulted in reduced body weight. decrease Ache level increases, SGOT, SGPT, ALP were observed while no significant alterations were noticed in any parameter in the II group animals, Histopathology of brain and lung of the chlorpyrifos treated animals shows the cellular deficit in the brain tissue and mild congestion in the lung tissue. The present study concluded that curry leaves are a rich source of phenolic, alkaloids, flavonoids and exhibit antioxidant and antimutagenic activity and appeared to be beneficial to rats to a great extent in attenuating and resulting in the damage sustained by chlorpyrifos exposure.

Antioxidant, thrombolytic, cytotoxic and antibacterial activities of leaves of Vitex peduncularis

Vitex peduncularis (Verbenaceae), a perennial tree, is locally utilized for possessing multifaceted pharmacological properties including analgesic, antimalarial, anti-angina, antidiabetic, antioxidant, anti-inflammatory and hepatoprotective. Hence, this study aims to evaluate their antioxidant, thrombolytic, cytotoxic and antibacterial activities from the methanolic crude extract and its various solvent fractions. Data from antioxidant and thrombolytic assay displayed that Kupchan partitioned chloroform soluble fraction revealed the maximum phenolic content (73.39 mg of GAE/g of extract), DPPH free radical scavenging activity (26.69 μg/ml) and thrombolytic activity (37.35%). In brine shrimp lethality evaluation, the LC50 values indicate that the most cytotoxic compound was found to be from ethyl acetate soluble fraction (LC50 6.73 μg/ml). Finally, antibacterial activity of different fractions showed that both chloroform and methanolic fraction possessed mild activity against the tested bacteria. The potential biological effects of the crude fractions have been demonstrated demanding future studies of the isolated compounds to assess these activities. Bangladesh J. Sci. Ind. Res. 57(4), 239-246, 2022

Anti-Melanogenesis Effect of Rosa rugosa on α-MSH-Induced B16F10 Cells via PKA/CREB Pathway Activation

Melanin protects the skin against UV damage, whereas excessive melanin accumulation causes abnormal pigmentation and even melanoma. It has been reported that Rosa rugosa exhibits antioxidant, anti-bacterial, anti-tumor, and anti-inflammation activities. The current study evaluated the melanogenesis-suppressing effect of R. rugosa extract and its solvent fractions (H2O, n-BuOH, 85% aq. MeOH, and n-hexane). The effect of R. rugosa on the extra/intra-cellular melanin and intracellular active tyrosinase levels, melanogenesis-related gene and protein expression, and PKA/CREB signaling pathway activation was investigated in α-MSH-induced B16F10 cells. The results showed that R. rugosa effectively suppressed melanin secretion and tyrosinase activity at non-cytotoxic concentrations. R. rugosa extract down-regulated the melanogenesis-related expression of genes and proteins of tyrosinase, microphthalmia-associated transcription factor (MITF), tyrosinase-related protein (TRP)-1, and TRP-2. Furthermore, R. rugosa effectively inhibited the phosphorylation of the PKA/CREB proteins. Finally, the total polyphenol content of R. rugosa crude extract and its H2O, n-BuOH, 85% aq. MeOH, and n-hexane solvent fractions were 1383.9 ± 44.5, 2004.7 ± 43.4, 7270.3 ± 54.5, 2064.1 ± 34.8, and 1091.1 ± 26.2 mg gallic acid equivalent/100 g extract, respectively. The anti-melanogenesis effect of R. rugosa was suggested to be exhibited by downregulating the PKA/CREB signaling pathway potentially due to a high content of polyphenols. Overall, R. rugosa crude extract and its solvent fractions could be considered sources of bioactive ingredients that can be used against hyperpigmentation.

Lignin Stabilization and Carbohydrate Nature in H-transfer Reductive Catalytic Fractionation: The Role of Solvent Fractionation of Lignin Oil in Structural Profiling.

Reductive Catalytic Fractionation (RCF) of lignocellulosic materials produces lignin oil rich in monomer products and high-quality cellulosic pulps. RCF lignin oil also contains lignin oligomers/polymers and hemicellulose-derived carbohydrates. The variety of components makes lignin oil a complex matrix for analytical methods. As a result, the signals are often convoluted and overlapped, making detecting and quantifying key intermediates challenging. Therefore, to investigate the mechanisms underlining lignin stabilization and elucidate the structural features of carbohydrates occurring in the RCF lignin oil, fractionation methods reducing the RCF lignin oil complexity are required. This report examines the solvent fractionation of RCF lignin oil as a facile method for producing lignin oil fractions for advanced characterization. Solvent fractionation uses small volumes of environmentally benign solvents (methanol, acetone, and ethyl acetate) to produce multigram lignin fractions comprising products in different molecular weight ranges. This feature allows the determination of structural heterogeneity across the entire molecular weight distribution of the RCF lignin oil by high-resolution HSQC NMR spectroscopy. This study provides detailed insight into the role of the hydrogenation catalyst (Raney Ni) in stabilizing lignin fragments and defining the structural features of hemicellulose-derived carbohydrates in lignin oil obtained by the H-transfer RCF process.

C-glycosyl flavones in &lt;em&gt;Passiflora incarnata&lt;/em&gt;

Brazil has a diversity of plant species and many of them are medicinal plants used in the production of herbal medicines. Passiflora incarnata is popularly known as passion fruit, its fruits and aerial parts have anxiolytic and sedative properties. Recent studies have shown that P. incarnata has several bioactive compounds such as indole alkaloids, cyanogenic glycosides, maltol and flavonoids. Among the substances identified in the species, vitexin has action on the Central Nervous System, interfering with the functioning of gamma-aminobutyric acid. Thus, the objective of the study was to identify and quantify the vitexin present in the ethyl acetate fraction of the aerial parts of the passion fruit. For this, the aerial parts of P. incarnata were submitted to extraction with ethanol, followed by fractionation in organic solvents, obtaining the hexane, dichloromethane and ethyl acetate fractions. The presence of vitexin in the ethyl acetate fraction was verified by Thin Layer Chromatography (TLC) and the total flavonoid content by colorimetric reaction in a spectrophotometer. The quantification of vitexin was performed by High Performance Liquid Chromatography (HPLC). The total flavonoid content was 5.34 mg/g and 960 µg/g of vitexin in the ethyl acetate fraction. Studies like this contribute to the development of new pharmaceutical formulations from the substance vitexin.

Fractionation of Raw and Parboiled Rice Husks with Deep Eutectic Solvents and Characterization of the Extracted Lignins towards a Circular Economy Perspective.

In the present work, rice husks (RHs), which, worldwide, represent one of the most abundant agricultural wastes in terms of their quantity, have been treated and fractionated in order to allow for their complete valorization. RHs coming from the raw and parboiled rice production have been submitted at first to a hydrothermal pretreatment followed by a deep eutectic solvent fractionation, allowing for the separation of the different components by means of an environmentally friendly process. The lignins obtained from raw and parboiled RHs have been thoroughly characterized and showed similar physico-chemical characteristics, indicating that the parboiling process does not introduce obvious lignin alterations. In addition, a preliminary evaluation of the potentiality of such lignin fractions as precursors of cement water reducers has provided encouraging results. A fermentation-based optional preprocess has also been investigated. However, both raw and parboiled RHs demonstrated a poor performance as a microbiological growth substrate, even in submerged fermentation using cellulose-degrading fungi. The described methodology appears to be a promising strategy for the valorization of these important waste biomasses coming from the rice industry towards a circular economy perspective.

A polyethyleneimine-functionalized polymer substrate polar stationary phase

A polyethyleneimine (PEI)-functionalized polymer substrate polar stationary phase was prepared for hydrophilic interaction chromatography (HILIC) by grafting PEI onto poly(styrene-divinylbenzene) (PS-DVB) microspheres. The phase shows a U-shape retention profile and it exhibits typical hydrophilic characteristic when the organic solvent fraction in the mobile phase is > 60%. Hydrogen bonding, anion exchange, and hydrophobic interaction are involved in the retention mechanism. Good separation and unique selectivity for acidic, basic and neutral polar analytes were achieved. It showed extremely low column bleed (comparable to that of blank) under gradient elution mode (even to 50% fraction of water) and wide pH tollerance range (at least 1–13).