Aqueous Fraction Research Articles

Ribes khorasanicum: A Potent Antioxidant Against Organ Toxicity by Effect on the NF‐κB Pathway

ABSTRACTAcetaminophen (APAP) is a well‐known drug that, in high doses, induces hepatotoxicity and nephrotoxicity. This study has investigated the preventive effect of the extract and fractions of Ribes khorasanicum on APAP‐induced liver and kidney damage. In this experiment, after analysis of the extract using FTIR, toxicity was induced by APAP on the 7th day. Before that, the extract and their aqueous, ethyl acetate, and n‐hexane fractions were administrated orally. 24 h after APAP administration, the animals were sacrificed. The liver and kidney were removed for the evaluation of oxidation and biochemical markers, including SGOT, SGPT, ALP, LDH, albumin, urea, creatinine, and bilirubin and also for histopathological evaluations. The safety of the extract was evaluated based on the MTT. Also, expression of the NF‐kB is done. Administration of Ribes khorasanicum significantly decreased the biochemical parameters compared to the APAP. Oxidative parameters, as well as histopathological changes in preventive groups, were improved compared to the APAP in both tissues. The results showed that the aqueous and ethyl acetate fractions of the extract had a better effect than the whole extract and n‐hexane fraction against APAP toxicity.

Phytoconstituents and In Vitro Free Radical Scavenging Potential of n-Hexane and Aqueous Fractions of Cucurbita maxima and Leptadenia hastata

The present study explored the phytoconstituents and radical scavenging activity of the respective n-hexane and aqueous fractions of Cucurbita maxima (CMHF and CMAF) and Leptadenia hastata (LHHF and LHAF) for potential application in oxidative stress-related ailments. The phytoconstituents were qualitatively determined and characterized using Fourier-transform Infrared (FTIR), while the antioxidant activity was determined in vitro. Alkaloids were present in only the aqueous fractions of C. maxima and L. hastata, while saponins, steroids, and flavonoids were detected in all the fractions. The FTIR revealed the presence of functional groups, including alcohols, sulfonates, alkenes, alkanes, amines, and aromatics in both plant fractions. The LHHF (35.53 ±2.11 ascorbic acid (AA) equivalent µg/mL) exhibited a significantly (p<0.05) higher total reducing power (TRP) than all the other fractions. The CMHF (69.11 ±2.56 AAE µg/mL) demonstrated a significantly (p<0.05) higher total antioxidant capacity (TAC) than all the other fractions. For the ferric thiocyanate (FTC) assay, the highest inhibition was exhibited by LHHF (79.78 ± 3.24%), significantly (p<0.05) higher than AA (26.46 ± 2.12%), CMHF (69.77 ± 3.16%), and CMAF (43.80 ± 2.12%). In the thiobarbituric acid assay, the lowest MDA concentration was exhibited by the CMHF (0.07 ±0.01 nmol/mL), significantly (p<0.05) lower than all the other fractions and ascorbic acid. Conclusively, the n-hexane fraction of both plants presents potential sources of novel antioxidant compounds with significant free radical scavenging and anti-lipid peroxidation activities, applicable in ailments linked to oxidative stress.

Evaluation of the Antioxidant Power and Secondary Metabolites Contents of the Crude Compounds of Talinum triangulare (Talinaceae)

Talinum triangulare is a food plant recognized for its nutritional properties and therapeutic virtues. This plant is used in particular in Daloa (Central-West Ivory Coast) by naturotherapists, for the treatment of malaria. This study aimed to evaluate the antioxidant activity of extracts and fractions of Talinum triangulare leaves and to determine their content of secondary metabolites. Two methods in vitro were used for this evaluation: reduction of the 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH) and reduction of the ABTS+ cation radical (2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid). The results show that the IC50 could not be determined for the 70 % aqueous and hydro-ethanolic extracts with the DPPH test, while it was respectively 0.9 and 2.3 mg/mL for the fractions dichloromethane and aqueous. Regarding the ABTS+ radical-cation reduction test, the dichloromethane fraction showed a higher percentage of inhibition (41.59 %) compared to the aqueous fraction (40.59 %), while the aqueous fraction was a little more important than the hydro-ethanolic extract at 70 % (38.29 %). Among the four compounds tested, only the aqueous extract presented a relatively low percentage of inhibition (25.51 %). Spectrophotometric analysis revealed the presence of various phenolic compounds, such as flavonoids, polyphenols and total tannins, at varying concentrations. These results could support the traditional use of Talinum triangulare in the treatment of malaria.

Exploration of New Drug Candidate Derived from Antioxidants of Korean Native Halophytes: Control of Acinetobacter baumannii with Antipathogenic Activity

The rise of antibiotic-resistant bacteria poses a significant challenge to the treatment of bacterial infections, necessitating the development of novel antibiotics or strategies to preserve the efficacy of existing ones. This study investigates the role of oxidative stress modulation in the pathogenicity of multidrug-resistant (MDR) bacterial strains, aiming to identify potential avenues for new drug design. Specifically, the anti-biofilm effects of crude extracts and fractions from seven halophyte species native to Jeju Island, South Korea, were evaluated against Acinetobacter baumannii ATCC 17978. Notably, the 85% aqueous methanol fraction of Peucedanum japonicum Thunb. (Pj) and the n-hexane fraction of Lysimachia mauritiana Lam. (Lm) demonstrated significant anti-biofilm activity. Further assessments revealed that these fractions also exhibited notable antioxidant and anti-inflammatory properties, with the Pj fraction showing a lifespan extension effect in the Caenorhabditis elegans model. These findings suggest that Pj and Lm hold promise as potential candidates for the development of new therapeutic agents targeting MDR bacteria.

In vivo evaluation of anti-diarrheal activity of hydroalcoholic extract and solvent fractions of the leaf of Leucas deflexa Hook.f (Lamiaceae) in rodents

The emergence of antibiotic-resistant bacteria has intensified the search for novel antidiarrheal drug. Plant-derived extracts offer promising alternatives due to their ability to modulate gut motility and enhance water absorption. The leaves of Leucas deflexa Hook.f., a plant native to Ethiopia, have been traditionally utilized in the treatment of diarrheal diseases. Nonetheless, its traditional application has yet to be scientifically confirmed. Hence, the aim of the present study was to evaluate antidiarrheal activity of the crude extract and fractions of the leaf of Leucas deflexa Hook.f (Lamiaceae). Healthy Swiss albino mice were randomly divided into five groups per experimental model: castor oil-induced diarrhea, gastrointestinal motility, and anti-enteropooling assays. The control group received distilled water (10ml/kg), while the positive control was treated with loperamide (3mg/kg). The remaining groups were administered various dosages (LD100, LD200, and LD400 mg/kg) of a hydroalcoholic extract or its fractions from Leucas deflexa Hook.f. The crude extract and chloroform fraction substantially (P<0.001) delayed the onset of diarrhea, reduced fecal frequency, and decreased total fecal weight at all administered doses compared to the negative control. The butanol and aqueous fractions exhibited a substantial antidiarrheal effect at doses of 200mg/kg and 400mg/kg, respectively. All treatments, including the crude extract, chloroform, butanol, and aqueous fractions, substantially (P<0.001) reduced the volume and weight of intestinal contents at various doses. Additionally, the chloroform, aqueous fraction, and crude extract at doses of 100, 200, and 400mg/kg substantially inhibited gastrointestinal motility compared to the negative control. The results of this study corroborate the traditional use of Leucas deflexa leaves in the treatment of diarrhea. These findings give a scientific justification for further exploration of the underlying mechanisms and potential therapeutic applications of this plant extract.

Rutile-phase Sn-Ti Mixed Oxides as Acid Catalysts for the Condensation of C2-C3 Oxygenated Compounds in Water.

The design of new cost-effective and water-resistant acid catalysts is crucial for valorizingaqueous side-streams to increase the efficiency and competitiveness of bio-refineries in a sustainable way. In this work, Sn-Ti mixed oxides are prepared via a green and scalable co-precipitation method. This synthesis procedure allows obtaining homogeneous rutile-phase Sn-Ti mixed oxides with enhanced textural properties and a higher amount of Lewis acid sites. More importantly, the catalytic behavior of these Sn-Ti mixed oxides is investigated by using an aqueous mixture of C2-C3 representative oxygenated compounds, closer to real industrial conditions and differing from usual individual probe molecules studies performed even in the absence of water. Catalytic experiments combined and correlated with spectroscopic measurements (i.e., XRD, TEM, FT-IR with pyridine adsorption-desorption and N2 adsorption) are performed to better understand the properties of different Sn-Ti catalysts. These materials show promising results in the condensation of light oxygenated compounds present in aqueous fractions. Homogeneous and robust rutile-phase structures with inherent hydrophobic characteristics turn these Sn-Ti materials into active and highly resistant catalysts capable to transform these low-value oxygenated compounds into a mixture of hydrocarbons and aromatics useful for blending with automotive fuels, especially under complex acidic aqueous environments and moderate process conditions.

In Silico Studies for Multi-Targeting Justicia Secund Phytochemicals Against Ovarian Cancer

ntroduction/Background of study: Ovarian cancer is the fifth leading cause of cancer deaths among women, accounting for more deaths than any other female gynaecological cancer, which includes cervical, uterine, vaginal and vulvar cancers. Current treatment options include surgery, platinum-based chemotherapy, radiation therapy and the use of targeted therapy such as poly ADP-ribose polymerase (PARP inhibitors), as well as immunotherapy. These therapy options, however, are subject to high rates of resistance and many side effects. AIM/ OBJECTIVES: This research aims to study other viable drug targets for ovarian cancer treatment, as well as new phytocompounds that can serve as new drug options using the in-silico approach. Materials/Methods: The ethanolic leaf extract of Justicia secunda was obtained using conventional methods. Liquid Liquid-liquid fractionation was performed with N-hexane, ethyl acetate and butanol solvents to obtain their fractions alongside the aqueous fraction. Vacuum Liquid Chromatography was performed with the N-hexane fraction and gradient mixtures of N-hexane/ethyl acetate and Dichloromethane/Methanol in various ratios to obtain the subfractions. The compounds were identified using Gas Chromatography-Mass Spectrometry (GC-MS). Full pharmacognostic profiling was performed on the J.secunda leaves. The identified compounds were downloaded from Pubchem and subjected to Molecular docking simulations to obtain their binding affinities with the receptors of interest. Drug-likeness and toxicity assessments were performed on frontrunner compounds. Results: After assessment of the frontrunner compounds, four multitargeting J.secunda phytochemicals were identified: Luteolin, Diosmetin, 5H-Quindoline and 10H-Quindoline.

Phytochemical Composition, Antioxidant, Anti-Helicobacter pylori, and Enzyme Inhibitory Evaluations of Cleistocalyx operculatus Flower Bud and Leaf Fractions.

Six solvent fractions isolated from flower bud and leaf ethanolic extracts of Cleistocalyx operculatus were analyzed for their phytochemical contents, including phenolics, flavonoids, saponins, tannins, and alkaloids. Antioxidant activities were measured using the ABTS, DPPH, and FRAP assays. The results showed that the flower bud aqueous fraction (BAF) and the leaf aqueous fraction (LAF) rich in phenolic content (768.18 and 490.74 mg GAE/g dry extract, respectively) exhibited significantly higher antioxidant activities than the other fractions. The flower bud hexane fraction (BHF) had remarkably high flavonoid and saponin contents (134.77 mg QE/g and 153.33 mg OA/g dry extract, respectively), followed by that of the leaf hexane fraction (LHF) (76.54 mg QE/g and 88.25 mg OA/g dry extract, respectively). The BHF and LHF were found to have extremely high antibacterial activity against two H. pylori strains, ATCC 51932 and 43504 (MICs of 125 µg/mL). Interestingly, DMC (2',4'-Dihydroxy-6'-methoxy-3',5'-dimethylchalcone) isolated from the BHF displayed greater antibacterial activity against the bacterial strains (MICs of 25-50 µg/mL) than those of the fractions. In addition, DMC presented potent inhibitory effects on H. pylori urease (IC50 of 3.2 µg/mL) and α-amylase (IC50 of 83.80 µg/mL), but no inhibition against α-glucosidase. It was also demonstrated that DMC showed pronounced inhibitory effects on the urease activity and biofilm formation of H. pylori, and could increase the membrane permeability of the bacterial cells. Scanning electron micrographs depicted that the BHF and DMC had strong effects on the cell shape and significantly induced the distortion and damage of the cell membrane. The fractions and DMC showed no significant toxicity to four tested human cell lines. Efforts to reduce antibiotic use indicate the need for further studies of the flower buds and DMC as potential products to prevent or treat gastric H. pylori infections.

Fe(II)-Catalyzed Recrystallization Drives Phosphorus and Aluminum Release from Goethite.

Goethite often harbors impurities, such as phosphorus (P) and aluminum (Al), which are incorporated into its structure through direct substitution or coprecipitation with nanocrystalline phases. Understanding the processes that drive the release of P and Al from goethite is of paramount importance for the iron ore industry and for managing nutrient and pollutant behavior in the environment. This study investigates the impact of Fe(II)-catalyzed recrystallization on the release of P and Al from goethite. We evaluated the solubility and extractability of P and Al in suspensions of Al- and P-coprecipitated goethite, treated with 57Fe-enriched Fe(II)aq under oxygen-free conditions for 30 days at neutral pH and room temperatures. The addition of Fe(II)aq induced the recrystallization of goethite dominant initial synthetic phases (i.e., low P- and Al-containing phases) and the transformation of higher P- and/or Al-bearing starting material that was actually a mixture of goethite and minor amounts of lepidocrocite and feroxyhyte. Our results reveal that Fe(II)-catalyzed mineral and structural evolution led to the repartitioning of P and, to a lesser extent, Al throughout the crystal structure, mineral surface, and aqueous solution. Following a 30 day reaction with Fe(II)aq, we extracted approximately 80, 68.8, 73.9, and 83.2% of P from P-only, low, medium, and high P + Al goethite, respectively. Additionally, we observed total Al removals of approximately 17, 27, and 25% from low, medium, and high P + Al goethite, respectively. The results demonstrate that treating both P-only and P + Al goethite with Fe(II) at room temperature, followed by a 24 h extraction using 1 M NaOH, significantly enhances the overall extractability of P and Al, including both aqueous and surface-adsorbed fractions, compared to Fe(II)-free controls. These findings advance our understanding of the recrystallization process and impurity substitution in goethite, offering promising avenues for developing new environmentally friendly methods to extract P and other impurities from goethitic iron ores at lower temperatures.

Antioxidant and Antifungal Activities and Characterization of Phenolic Compounds Using Ultra-High Performance Liquid Chromatography and Mass Spectrometry (UPLC-MS) of Aqueous Extracts and Fractions from Verbesina sphaerocephala Stems.

The Verbesina gender represents the second most diverse group from the Asteraceae family in Mexico; Verbesina sphaerocephala is one of the most distributed species along the Mexican territory. This species has been poorly studied, reporting the presence of some bioactive compounds with antioxidant and antibacterial activity. In this study, phenolic and flavonoid contents and composition, antioxidant and antifungal activities of aqueous extracts of the stem of V. sphaerocephala and its fractions were determined. The results showed that the highest antifungal activity against Botrytis cinerea was shown by the aqueous extract (IC50: 0.10 mg/mL) and the ethyl acetate fraction (IC50: 14.8 mg/mL). In addition, the aqueous extract and the ethyl acetate fraction exhibited the highest phenolic (21.40 and 21.26 mg gallic acid equivalents per gram of dry extract, respectively) and flavonoid contents (11.53 and 3.71 mg rutin equivalents, respectively) and high antioxidant activity determined by the Total Antioxidant Capacity (20.62 and 40.21 mg ascorbic acid equivalents per gram of dry extract, respectively), Ferric Reducing Power (74.76 and 129.57 mg gallic acid equivalents per gram of dry extract, respectively), DPPH (IC50: 12.38 and 7.36 mg/mL, respectively), and ABTS (IC50: 5.60 and 7.76 mg/mL, respectively) methods. Twelve phenolic compounds were detected in the aqueous extract using UPLC-MS analysis, of which the major ones were protocatechuic, vanillic, and hydroxybenzoic acid, while in the ethyl acetate fraction, the presence of 18 phenolic compounds were identified, of which the majority were vanillin, rutin, and hydroxybenzoic acid. The results of this research demonstrate that the aqueous extract of V. sphaerocephala stems has phenolic compounds with antifungal and antioxidant activity.

Unraveling the Antidiabetic Effect of Alternantera brasiliana (L.) Kuntze: A Combined in Vitro and in Vivo Approach

Background of the study This study established the antidiabetic efficacy of Alternantera brasiliana in vitro and in vivo, identified the most active fraction and profiled the chemical constituents of the most active fraction. Methodology The leaf of A. brasiliana was air-dried, pulverized and extracted with methanol and evaluated for its α-amylase activity at different concentrations using in vitro method. The in vivo antidiabetic activity of the extract and glibenclamide was evaluated in glucose loaded and streptozotocin-induced diabetic rats using various doses, while the most active partitioned fraction was identified using glucose loaded method followed by identification of its chemical constituents through GC-MS analysis. Results The extract elicited good α-amylase inhibitory potential with IC50 = 0.45 mg/mL. Also, the 50 mg/kg dose demonstrated the highest percentage blood glucose level reduction and significantly ( P &gt; 0.05) comparable to glibenclamide (5 mg/kg) from 0.5 to 4 h. The streptozotocin-induced antidiabetic assay showed that the 50 mg/kg demonstrated better activity than glibenclamide (5 mg/kg) and was significantly comparable on days 10 and 14. The aqueous methanol fraction was the most active fraction with 53% blood glucose level reduction at 4 h. The secondary metabolite profiling identified 30 chemical compounds whereby 1H-Indole-2-carboxylic acid, 6-(4-ethoxyphenyl)-3-methyl-4-oxo-4,5,6,7-tetrahydro-, isopropyl ester, Benzo[h]quinoline, 2,4-dimethyl-, thymol and 13,5-trioxane as the major constituents. Conclusion The antidiabetic activity demonstrated by the A. brasiliana extract established its antidiabetic efficacy

Nutmeg (Myristica fragrans) Extracts Accelerate Oral Mucosal Wound Healing In Vivo

Background: Oral mucosal pain and sores are common concerns in dental care, often resulting from surgeries, infections, trauma, or autoimmune disorders. Conventional treatments like NSAIDs offer relief but carry adverse side effects. Nutmeg (Myristica fragrans) has been traditionally used for its analgesic, anti-inflammatory, and antimicrobial properties. However, its potential in oral mucosal wound healing remains underexplored. Methods: This study utilized male Wistar rats (Rattus norvegicus) to assess the wound healing effects of nutmeg extracts and fractions. Nutmeg was extracted using maceration, and the fractions were obtained through liquid-liquid extraction. Rats were divided into control and treatment groups, and topical nutmeg treatments were applied daily to incised gingival mucosa. Wound closure time was monitored daily, and healing rates were analyzed. Results: The ethyl acetate fraction of nutmeg exhibited the fastest wound healing, achieving an average healing rate of 88.79%, closely matching the positive control (94.65%). Other fractions also demonstrated efficacy, with the aqueous fraction achieving 82.46% and the ethanol fraction 75.54%. The hexane fraction showed the slowest healing at 63.67%. Statistical analysis revealed significant differences between the groups (p &lt; 0.05). Conclusion: Nutmeg extracts, particularly the ethyl acetate fraction, significantly accelerated wound healing in the oral mucosa of Wistar rats, highlighting its potential as a natural wound-healing agent. Further research is needed to isolate the bioactive compounds responsible for these effects and to explore their clinical applications in dental care.

Antimalarial potentials of Solanum dasyphyllum fractions against Plasmodium berghei infected mice

BackgroundThe leaves of Solanum dasyphyllum are commonly utilized in the management of fever in traditional medicine, yet scientific evidence supporting their antimalarial effectiveness is lacking. ObjectiveThus, this study aimed to assess the antioxidant properties of solvent fractions derived from these leaves, alongside investigating antimalarial potential against Plasmodium berghei in mice. MethodsAntioxidant activity was evaluated through total phenolic content determination, DPPH radical scavenging, and Ferric ion reducing antioxidant power assay. The fractions were tested against Plasmodium berghei (NK65) in 4-day suppressive, prophylaxis, and curative models, with mice orally administered 1% Tween80 (control), Solanum dasyphyllum hexane fraction (SdHXF), Solanum dasyphyllum dichloromethane fraction (SdDMF), Solanum dasyphyllum ethyl-acetate fraction (SdEAF), and Solanum dasyphyllum aqueous fraction (SdAQF) (each at 125mg/kg), and chloroquine (10 mg/kg). IC50 values were determined via linear regression analysis, and antimalarial study results were statistically analyzed using one-way ANOVA followed by Duncan multiple range tests, considering significance at P value < 0.05. ResultsThe SdHXF (60.4%), SdDMF (56.8%), SdEAF (86.4%), and SdAQF (94.8%) exhibited notable percentage chemosuppression compared to the control in the 4-day suppressive test. In the prophylaxis test, SdEAF (80.6%) and SdAQF (80.0%) demonstrated similar percentage chemosuppression. In the curative test, the mean survival time significantly increased in SdHXF (30.2 ± 1.3 days), SdDMF (30.8 ± 3.2 days), SdEAF (31.4 ± 2.3 days), and SdAQF (30.1 ± 2.0 days) compared to the control (10.3 ± 0.1 days). The antioxidant activity of the fractions increased with concentration; however, it was lower than that of the positive controls (gallic acid and ascorbic acid). ConclusionThese results suggest that the fractions possess potent antiplasmodial activity against Plasmodium berghei, particularly in the mid-polar fractions, indicating the potential of the plant as a source of novel antimalarial agents.

In vitro and in vivo pharmacological evaluation of polygonum persicaria l.

The present study was designed to investigate the in vitro antioxidant, cytotoxic, anthelmintic and in vivo analgesic, anti-diarrheal, hypoglycemic and CNS anti-depressant properties of different solvent fractions of methanol extract of leaf and flower of Polygonum persicaria L., a notable medicinal plant in Bangladesh. The crude methanol extracts were partitioned separately to petroleum-ether, carbon tetrachloride, chloroform and aqueous fractions. In DPPH scavenging assay for antioxidant test, the aqueous fraction of flower extract showed maximum antioxidant activity with IC50 of 0.60 μg/ml. Most of the fractions revealed prominent lethality (LC50) against brine shrimp nauplii. The test samples also exhibited dose-dependent anthelmintic activity against Pheretima posthuma. The leaf extract and flower extract (200-and 400 mg/kg b.w.) can decrease the painful sensation in mice. Leaf extracts and flower extracts displayed 57.69 and 50% reduction of diarrhea induced by castor oil in mice, respectively. The plant samples exhibited hypoglycemic effect and CNS anti-depressant effect in mice. Based on the possibility of bioactivity, the plant can be thoroughly examined to determine its potential efficacy and to support its traditional uses. Bangladesh J. Bot. 53(3): 475-485, 2024 (September)

Antioxidant, membrane stabilizing and thrombolytic potentials of the leaves of erythrina fusca lour

Erythrina fusca (Family: Fabaceae) is famous for many traditional healing. In the present study, the leaves of E. fusca were collected, dried, powdered and then extracted with methanol. It was further partitioned into n-hexane, dichloromethane and aqueous soluble fractions. All the extracts were subjected to antioxidant, membrane stabilizing and thrombolytic assays. In case of free radical scavenging assay, the aqueous soluble fraction showed highest scavenging activity. In ferric reducing anti-oxidant power assay, the dicholoromethane extract showed highest reduction of ferric ion in a dose dependent manner. In total antioxidant assay, the methanol extract and dichloromethane extract showed stronger capacity as antioxidant. During the determination of total phenolic and flavonoid contents, the methanol extract and dichloromethane soluble fraction showed higher contents of phenolics and flavonoids, respectively. The erythrocyte membrane stabilizing assay revealed the capacities of methanol extract and its aqueous fraction to stabilize the RBC membrane in both hypotonic solution- and heat- induced hemolytic conditions. However, the clot lysis ability of the E. fusca leaf extracts was not so prominent. Bangladesh J. Bot. 53(3): 439-445, 2024 (September)

Comparison between Co(II) and Ni(II) cycling at goethite-water interfaces: Interplay with Fe(II)-catalyzed recrystallization

Cobalt (Co) and nickel (Ni) are critical metals for modern renewable energy technologies as well as essential micronutrients for terrestrial plant health and marine primary production. Both metals are commonly surface-adsorbed onto and/or structurally-incorporated into iron (oxyhydr)oxide minerals, such as goethite (α-FeOOH), that are ubiquitously present in soils and sediments at the Earth’s surface. In sub- and anoxic environments, aqueous ferrous iron (Fe(II)) generated from dissimilatory Fe(III) reduction can induce the recrystallization of goethite and subsequently influences the speciation and mobilization of associated metals, e.g., Co(III) being reduced to Co(II). While it is generally considered that divalent Co and Ni behave similarly at goethite-water interfaces, there lacks a direct comparison of their cycling through goethite in response to Fe(II)-catalyzed recrystallization. Here, under circumneutral anoxic conditions with and without addition of aqueous Fe(II), we performed batch reaction experiments on Co(II)-substituted goethite and Co(II) and Ni(II) sorption experiments on pure goethite. The redox state and coordination environment of Co associated with goethite were determined using high energy resolution fluorescence detected X-ray absorption spectroscopy at the Co K-edge, and the distribution of solid-bound Co and Ni in goethite following sorption was revealed by sequential dissolution. Our results show that substitution of Co(II) for Fe(III) in goethite has less negative feedback on Fe(II)-catalyzed recrystallization than Ni(II), which may be related to their differing structural distortions as evidenced by EXAFS. In the absence of Fe(II), aqueous Co(II) is more favourably adsorbed onto and incorporated deeper into goethite than Ni(II), suggesting that Co(II) is more structurally compatible with goethite. The presence of Fe(II) markedly enhances the structural incorporation of both Co(II) and Ni(II) as a result of goethite recrystallization, which in turn can be inhibited by the accumulation of metals at the mineral surface. Furthermore, structurally-incorporated Co(II) is more difficult to be released back into solution (i.e. sum of aqueous and extract fractions) than Ni(II) during Fe(II)-catalyzed goethite recrystallization. Overall, our work highlights the significant differences between Co(II) and Ni(II) in their cycling at goethite-water interfaces and intricate interplay with Fe(II)-catalyzed recrystallization. This improves our understanding of their mobilization and distribution in anoxic goethite-rich systems and can provide useful insights for their enrichment and extraction from natural and artificial laterites generated from the enhanced weathering of ultramafic mine tailings.

Antiradical effect and phytochemical characterisation of the leaves of Parkia platycephala Benth

The objective of this study was to isolate and identify compounds present in the leaves of Parkia platycephala Benth (Leguminosae-Mimosoideae) and evaluate the antiradical potential of the derived extracts and fractions. Seven compounds were successfully isolated from the ethanolic leaf extract, comprising gallic acid, flavonoids, triterpenoids, and phytosteroids. Structural identification was accomplished through comprehensive spectroscopic data analysis, including NMR and mass spectrometry (ESI-MS), and comparison with existing literature. The antiradical efficacy of both the extract and its fractions was determined in vitro through assays measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and quantifying total phenolics via UV/Vis, revealing notable antioxidant activity in extracts from P. platycephala Benth, especially in the EtOH, EtOAc, and aqueous fractions, attributed to their high phenolic content and prevalence of flavonoids. These findings contribute to a deeper understanding of Parkia’s chemical composition and its potential biological benefits.

Hypoglycemic, hypolipidemic and antioxidant potential of Myrcia pubipetala in an animal model of type 1 diabetes

Myrcia genus plants, like Myrcia pubipetala, traditionally used as hypoglycemic agents, hold promise for Type 1 Diabetes Mellitus (DM1) research but need more comprehensive chemical and pharmacological investigation. This is an experimental study involving controlled administration of treatments to a group of rats to assess their effects compared with a control group, investigating the effects of M. pubipetala on alloxan-induced Type 1 Diabetes Mellitus in rats. After the induction of diabetes, the rats received the hydroalcoholic extract (HAE) or aqueous fraction (AF) (25, 50, 100, or 150 mg kg-1) of M. pubipetala, or water. The results showed that diabetic rats presented cell damage in kidneys, oxidative stress, and high levels of glucose and triglycerides in their plasma and erythrocytes. The HAE (150 mg kg-1), per se, reduced lipid and protein oxidation, and the AF (150 mg kg-1) decreased lipoperoxidation. AF (150 mg kg-1), per se, decreased triglyceride levels. Conclusion: treatment with HAE and AF reduced oxidative damage, positively modulated antioxidant defenses, and exerted hypoglycemic and hypolipidemic effects, representing a potential adjuvant treatment for diabetes.

Aqueous fractionation of mucilage and protein from Camelina sativa seeds and defatted meal

Camelina protein and mucilage are being investigated as coproducts in addition to the oil. It has been reported that the significant amount of mucilage (10–11 %) in the seed coat interferes with the recovery of the protein. In this work, two schemes of producing mucilage and protein fractions from camelina seeds were evaluated and proximate composition of each process stream was analyzed. In the sequential extraction process, mucilage was first separated from hydrated seeds, then oil from degummed seeds, and lastly the protein from the defatted degummed meal. In the other process, aqueous fraction rich in protein and carbohydrates were extracted simultaneously from defatted meal. Proteins were obtained by alkali solubilization and acid precipitation method. Sequential extraction produced a mucilage fraction with 15.2 % protein content and a protein isolate (90.2 % crude protein). Simultaneous aqueous extraction of the defatted meal produced a mucilage fraction with 48.9–50.2 % protein content and a protein concentrate (67.4 and 75.6 % crude protein). The whey obtained had similar protein and soluble carbohydrates contents of 24.4–26.4 % and 56.5–58.2 %, respectively. The difference in composition of the mucilage, protein and whey fractions produced by each process will determine the applications of these products.

IN VITRO ANTIMICROBIAL ACTIVITIES OF VARIOUS SOLVENT EXTRACTS DERIVED FROM VIOLA ODORATA

The primary objective of this study was to assess the antimicrobial activities of various polar and nonpolar solvent extracts derived from the leaves of Viola odorata. The disc diffusion method was employed to test the antimicrobial susceptibility against a diverse range of pathogenic microorganisms, including Escherichia coli, Erwinia carotovora, Klebsiella pneumoniae, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhi, Staphylococcus aureus and the fungus Candida albicans. The results indicated that isobutanol and ethyl acetate fractions exhibited significantly higher antimicrobial activity compared to petroleum ether, crude, chloroform and aqueous fractions. Among the tested bacteria, E. carotovora was the most susceptible bacterium to all the extracts of V. odorata, whereas S. typhi demonstrated the highest resistance. The isobutanol extract inhibited the proliferation of E. carotovora by 62 % at a concentration of 2 mg disc-1, while the ethyl acetate extract achieved 53% inhibition under the same conditions. Additionally, our findings revealed that the overall antimicrobial activity of V. odorata leaves was consistently effective against both Gram-positive and Gram-negative bacterial strains.