DPPH Radical Scavenging Activity Research Articles

Cadmium oxide nanoparticles from new organometallic Cd(II)-Schiff base complex and in vitro biological potentials: dual S. aureus and E. coli DNA gyrase inhibition by the precursors via in silico binding modes’ study

AbstractAt the nanoscale level, several biological processes take place, owing to the potential that engineered nanomaterials might interrelate with bio-molecules and cellular procedures. This study aimed to synthesize cadmium oxide nanoparticles via a one-step calcination process of tetradentate Schiff base-Cd(II) complex at different temperature ranges. The as-synthesized compounds were carried out via a viz UV–visible, elemental analysis, 1H NMR, molar conductivity, transmission electron microscopy (TEM), FT-IR spectroscopy, and X-ray diffraction (PXRD). The band gap energy and average particle sizes of the CdO particles are respectively (2.69 eV, 3.54 eV), 26.88 nm for CdO@250, and (3.20 eV, 3.57 eV), 25.67 nm for CdO@300, while CdO@350 exhibited the 3.78 eV and 28.42 nm values. The antioxidant accomplishments of the test samples through the scavenging activity of DPPH radicals showed CdO@300 to possess (IC50 = 5.18 ± 0.56 µg/mL). Similarly, the as-synthesized CdO nanoparticles exhibited higher antibacterial activities against S. aureus and E. coli as compared to the corresponding Cd-HMB and ligand (HMB), while ciprofloxacin acted as a standard antibiotic. Furthermore, HMB and its complex Cd-HMB were docked against the DNA gyrase enzymes of S. aureus (PDB IDs: 5CDQ) and E. coli (PDB IDs: 6F86) as receptors. The binding sites docking results showed that the binding energies of HMB and Cd-HMB to 5CDQ ranged from − 3.44 to − 4.99 kcal/mol and from − 6.45 to − 6.64 kcal/mol, while the binding energies related to the target 6F86 are in the ranges of (− 3.64, − 4.76) kcal/mol and (− 6.08, − 6.09) kcal/mol respectively. Therefore, the significant antioxidant and antibacterial activities of the ligand (HMB), Cd-HMB, and CdO NPs review the broad application prospects of these compounds as therapeutic agents for wide-ranging biomedical applications.

Potential use of hazelnut (Corylus avellana L.) shell powder in muffin production by partial substitution of wheat flour: Color, bioactive, textural, and sensory properties

In this study, different muffin samples were produced by substituting 0, 5, and 10% (w:w) hazelnut shell powder (HSP) into wheat flour and their color, bioactive, textural and sensory properties were determined. The results showed that both total phenolic content and DPPH radical scavenging activity did not change with the addition of HSP to the muffin formulation. Upon enrichment of muffins with HSP, L* and b* color values of muffins decreased in both crumb and crust, while a* values increased in crumb and decreased in crust. The more HSP used in the muffins, the more visible pore formation was determined. Textural analysis revealed that hardness, gumminess, chewiness values decreased while the springiness, cohesiveness and resilience values increased as the amount of HSP increased in the muffin formulation. The partial substitution of wheat flour with 5% (w:w) HSP received the highest crust, crumb, chewiness, taste/aroma and overall acceptability scores by the panelists. Overall, HSPs, which are a waste and by-product of hazelnut processing, can be successfully used in fiber-rich muffin production, both expanding their potential areas of use and contributing to their economic value.

Antidiabetic, antioxidant, and phytochemical profile of Pennisetum glaucum cultivated in central-southern Morocco and imported from India

Alternative methods of producing food sustainably are being considered due to rapid expanding population, increasing food needs, declining agricultural soils fertility, and ongoing drought. To achieve that, we examined the pharmacological, functional, and nutritional characteristics of two cultivars of pearl millet (Pennisetum glaucum), which are distinguished by their ability to tolerate a variety of climates compared to other cereal grains. In this study, we evaluated the antioxidant and antidiabetic effects of two seeds cultivars: one cultivated in Morocco and the other grown in India. In addition to having a higher energy value (403.91 Kcal), higher protein (9.13 %) and lipid content (7.11 %), and a lower capacity for self-oxidation than the Indian variety due to its fatty acid composition, the content of phenolic compounds of Moroccan millet is well concentrated in its seeds, making it more powerful as an antioxidant and hypoglycemic plant. The ethanolic extract of Moroccan pearl millet showed the greatest total phenolic content (36.278 mg GAE/g extract), DPPH and ABTS radical scavenging activity (IC50 = 152.286 and 252.480 μg/mL respectively), α-amylase and α-glucosidase inhibitory activity (IC50 = 84.439 μg/mL and 224.103 μg/mL respectively). The evidence gathered in this study indicates that P.glaucum possesses characteristics that qualify it as a food, medicinal, and productive plant.

Wound healing potential of a formula based on Populus nigra L. flower buds extract with anti-inflammatory activity

Ethnopharmacological relevanceWound healing is a complex and dysnamic process supported by a myriad of cellular events that are tightly coordinated to repair efficiently damaged tissue. Populus nigra L. (Salicaceae) flower buds are traditionally used in the treatment of dermatitis, upper respiratory tract infections, rheumatism and wounds. Aim of the studyThe aim of this study was to assess the wound healing potential of black poplar ointment containing 10 or 20 % of Populus nigra ethanolic flower buds extract using the excision model in rats. Materials and methodsTwo ointments (10 and 20 %) were prepared from Populus nigra flower buds ethanolic extract and topically applied on the area of excised skin of the rats for either 14 or 20 days. Morphological, macroscopic, histological and biochemical parameters were evaluated. ResultsThe results showed that the extract contained high amounts of total phenols (89.5 ± 7.7 mg caffeic acid equivalent/g of extract) and hydrolysable tannins (142.05 ± 2.55 mg tannic acid equivalent/g of extract), in correlation with strong DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity and beta-carotene bleaching with values of 96.31 ± 3.42 and 85.27 ± 1.79 %, respectively. Anti-inflammatory potential was illustrated by lipoxygenase and cyclooxygenase inhibition (52.80 ± 0.2 and 53.88 ± 2.55 %, respectively). Treatment with Populus nigra ointment (10 and 20 %) promoted wound contraction of 97.37 ± 1.19 and 97.28 ± 0.91 %, respectively. The antioxidant marker enzymes, catalase (0.10 ± 0.001; 0.08 ± 0.003 U/mg protein) and superoxide dismutase (363.34 ± 24.37; 317.82 ± 53.83 U/mg protein) activities in the granulation tissues were upgraded with respective treatments of 10 or 20 % ointment. Concurrently, the myeloperoxidase activity (2.21 ± 1.01; 2.13 ± 0.75 U/mg protein) was repressed, indicating anti-inflammatory potential, when compared to untreated, standard and excipient groups. Moreover, a significant increase in respective levels of hydroxyproline (p < 0.001) (28.05 ± 1.20; 25.29 ± 1.17 μg/mg tissue) and hexosamine (p < 0.05) (20.18 ± 1.21; 18.95 ± 1.98 μg/mg tissue) was triggered, reflecting a high regeneration of collagen in the scarred tissue. Histological examination of treated skin tissue revealed higher rates of re-epithelialization, lower neutrophils infiltration and re-vascularization in comparison to the control group. ConclusionGiven that the 10 % ointment was the optimal concentration, our findings offer an efficient drug formula for wound healing.

Molecular insight into the structural and functional aspects of arene Ru(II) complexes bearing bulky thiourea ligands

Herein we report four new arene ruthenium(II) complexes [RuII(ηAird et al. (2002)6-p-cymene)(L1)к1(S)Cl2] (C1), [RuII(ηAird et al. (2002)6-benzene)(L1)к1(S)Cl2] (C2) where L1 is N-((2,6-dimethylphenyl)carbamothioyl)benzamide (L1), and [RuII(ηAird et al. (2002)6-p-cymene)(L2)к1(S)Cl2] (C3), [RuII(ηAird et al. (2002)6-benzene)(L2)к1(S)Cl2] (C4) where L2 is N-((2,6-diisopropylphenyl)carbamothioyl)benzamide (L2) which were synthesized and evaluated for biological activity. The monodentate coordination of thione sulphur (S) to ruthenium ion along with two terminal chloride was confirmed by X-Ray diffraction analysis thus revealing a typical “piano-stool” pseudo tetrahedral geometry. DPPH radical scavenging activity showed that ligands were less efficient however on complex formation it showed significant efficacy with C4 showing the highest activity. The ligands and ruthenium complexes exhibited minimal to no cytotoxic effects on HEK cells within the concentration range of 10–300 μM. Evaluating the cytotoxicity against prostate cancer cells (DU145) L1, L2 and C1 displayed more pronounced cytotoxic activity with C1 showing high cytotoxicity against the cancer cells, in comparison to cisplatin indicating its potential for further investigation and analysis. Considering this, compound C1 was used to further study its interaction with BSA using fluorescence spectroscopy and it was found to be 2.64 × 106 M−1. Findings from CD spectroscopy indicate the binding in the helix region which was further confirmed with the molecular docking studies.

Acid-hydrolyzed phenolic extract of parsley (Petroselinum crispum L.) leaves inhibits lipid oxidation in soybean oil-in-water emulsions

The antioxidant activity of the natural phenolic extracts is limited in particular food systems due to the existence of phenolic compounds in glycoside form. Acid hydrolysis post-treatment could be a tool to convert the glycosidic polyphenols in the extracts to aglycones. Therefore, this research investigated the effects of an acid hydrolysis post-treatment on the composition and antioxidant activity of parsley extracts obtained by an ultrasound-assisted extraction method to delay lipid oxidation in a real food system (i.e., soybean oil-in-water emulsion). Acid hydrolysis conditions were varied to maximize total phenolic content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. When extracts were exposed to 0.6 M HCl for 2 h at 80 ℃, TPC was 716.92 ± 24.43 µmol gallic acid equivalent (GAE)/L, and DPPH radical scavenging activity was 66.89 ± 1.63 %. Not only did acid hydrolysis increase the concentrations of individual polyphenols, but it also resulted in the release of new phenolics such as myricetin and gallic acid. The extract's metal chelating and ferric-reducing activity increased significantly after acid hydrolysis. In soybean oil-in-water emulsion containing a TPC of 400 µmol GAE/L, the acid-hydrolyzed extract had an 11-day lag phase for headspace hexanal compared to the 6-day lag phase of unhydrolyzed extract. The findings indicated that the conversion of glycosidic polyphenols to aglycones in phenolic extracts can help extend the shelf-life of emulsion-based foods.

Optimising the recovery of phenolic compounds and antioxidant activity from orange peels through solid-state fermentation

It is widely recognised that orange peels contain a considerable quantity of phenolics, primarily in the form of glycosides. The process of fermentation holds potential as a viable method for extracting phenolic compounds and facilitating their biotransformation into novel metabolites. The aim of this study was to assess the enhanced release of phenolic compounds through the process of solid-state fermentation of orange peels using microorganisms. Following a 6-day incubation period, the methanol extract obtained from the sample fermented with starter Banh men exhibited the highest concentration of total phenolic compounds (17.57 ± 0.34 mg GAE/g DW) and demonstrated the most significant DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity (55.03%). The Reverse Phase High Performance Liquid Chromatography (RP-HPLC) analysis revealed that the predominant phenolic compounds in all fermented samples were flavonoid aglycones, specifically naringenin, hesperetin, and nobiletin. Conversely, in the unfermented orange peels, the major compound observed was the glycoside derivative hesperidin.

Antioxidant and antibacterial properties of stingless bee (Meliponula spp.) honey from the northern highlands of Tanzania, in comparison with Apis mellifera honey

Meliponiculture is an emerging practice in Africa where beekeeping is dominated with the management of the honey bees, Apis mellifera. Nevertheless, communities in the northern highlands of Tanzania have a long history of managing stingless bees for their honey which has putative medicinal value. The current study aimed to evaluate the antioxidant and antibacterial properties of honey samples from two stingless bee species, namely Meliponula (Axestotrigona) ferruginea and Meliponula (Axestotrigona) togoensis, in comparison with A. mellifera honey. Physicochemical properties were also determined to assess the quality of the studied honey samples. The honey samples conformed with the regional quality standards for moisture content, free acidity and HMF for both stingless bee and A. mellifera honey. Stingless bee honey exhibited stronger antioxidant potency, displaying higher mean values of total flavonoid (54.12 – 56.40 mg QE/100 g) and phenolic compounds (81.92 – 87.56 mg GAE/100 g), DPPH radical scavenging activity (65.81 – 68.40%) and ferric reducing antioxidant power (109.78 – 126.64 µmol Fe (II)/100 g) compared to A. mellifera honey (33.17 mg QE/100 g, 61.13 mg GAE/100 g, 41.44%, 65.00 µmol Fe (II)/100 g, respectively). Additionally, stingless bee honey demonstrated higher inhibitory effect against Staphylococcus aureus, Bacillus subtilis and Salmonella typhi, with minimum inhibitory concentrations ranging from 0.16 – 5% v/v, compared to 2.5 – 20% v/v for A. mellifera honey. These findings highlight the distinct bioactive properties of stingless bee honey and validate its applications in traditional therapy. More studies are encouraged to elucidate specific bioactive ingredients in stingless bee honey to further substantiate its medicinal potency.

Lipophilized rosmarinic acid: Impact of alkyl type and food matrix on antioxidant activity, and optimized enzymatic production

In this study, the initial focus was on exploring the simultaneous impact of the oil-based food matrix and the polarity of rosmarinic acid derivatives on the antioxidant properties. Rosmarinic acid (RA) showed remarkable DPPH, FRAP, and ABTS radical scavenging activities, followed by methyl rosmarinate (MR) and ethyl rosmarinate (ER). In bulk oil, both conjugated dienes and p-AnV values reached a peak in the following order after 30 days: ER > MR > RA = BHT > control (no antioxidant). In the oil structured using monoacylglycerol, MR was more effective than ER and RA. For ethyl cellulose oleogel, emulsion, and gelled emulsion systems, RA was more effective. Additionally, after confirming the importance of the food matrix on the antioxidant activity of RA derivatives, the lipophilization of RA with ethanol was optimized as a model with Lipozyme 435 in hexane. A conversion yield of as high as 85.59% for ER was achieved, as quantified by HPLC-UV and confirmed by HPLC-DAD-ESI-qTOFMS.

Isolation, Identification and in-Silico Characterization of Bioactive Peptide from the Venom Sac of Conus inscriptus

Nature has been the source of new medications since ancient times, and at least half of all commercialised pharmaceuticals have been made from renewable resources to treat various illnesses, including pain, inflammation, and infection. In recent years, interest has risen in bioprospecting of new bioactive peptides, especially for medical and health-related applications. Therefore, the production of functional meals is starting to get recognition for its potential to enhance quality of life when combined with a healthy lifestyle. In view of this, the current work aimed to isolate, purify, and identify bioactive peptides from Conus inscriptus venom sac protein extracts, with an emphasis on antioxidant and anti-inflammatory properties. The findings reveal that the DPPH radical scavenging activity, albumin denaturation, and HRBC membrane stabilisation inhibition activities of Conus inscriptus venom sac crude protein extracts are 23.76±2.4, 66.23±3.1, and 57.32±2.6% respectively. Secondary screening of purified protein fractions obtained through sephadex G100 gel filtration exhibited increased anti-inflammatory efficacy from fractions 19 to 23. Electrophoresis and PMF analysis revealed that the purified anti-inflammatory peptide was homogenous with a molecular weight of 12 KDa, and it was identified as a conotoxin MI15b precursor. The 3D model of conotoxin exhibits the highest similarity with template c6nk9A with a confidence of 54.1%, and its function was predicted as a potassium ion channel inhibitor. The findings of the Insilco characterisation of the conotoxin MI15b precursor concluded that this protein might serve as an anti-inflammatory agent and may be responsible for therapeutic actions in the medical management of many inflammatory-related disorders.

The Antioxidant and Whitening Effect of Miracle Fruit (Synsepalum dulcificum) Seed and Leaf Methanol Extracts

The seed and leaf 70% methanol extracts of miracle fruit (Synsepalum dulcificum) were investigated for its whitening activity for application as a functional ingredient in cosmetic products. At the leaf extract concentration of 100 mg/ml, the DPPH radical scavenging activity was found to be 94.58%, the ABTS&lt;sup&gt;+&lt;/sup&gt; radical scavenging activity was 36.62%. The total polyphenolic content of seed and leaf extract was 18.76 mgGAE/g, 71.42 mgGAE/g, respectively. The seed and leaf extracts reduced both tyrosinase activity and L-DOPA oxidation in a concentration-dependent manner. In B16F10 mouse melanoma cells, leaf extract inhibited 30% of melanin synthesis at 100 mg/ml. Miracle fruit seed and leaf extracts also inhibited the expression of melanogenesis genes such as microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein (TRP)-1. Moreover, reverse transcription-polymerase chain reaction of the extract showed that the mRNA expression of MITF, tyrosinase, and TRP-1 was decreased. The data suggested a protective role for the &lt;i&gt;Synsepalum dulcificum&lt;/i&gt; seed and leaf extracts against melanogenesis.

Impact of Drying Method and Solvent Extraction on Ethiopian Verbascum sinaiticum (Qetetina) Leaves: Metabolite Profiling and Evaluation of Antioxidant Capacity

The aim of this study was to evaluate the effects of different drying methods on bioactive compounds and to analyze their composition in Verbascum sinaiticum (V. sinaiticum) leaf extracts using UHPLC-ESI-QTOF-MS/MS. V. sinaiticum is traditionally used as an herbal medicine, yet it has undergone limited scientific investigations regarding its secondary metabolites. V. sinaiticum leaves were dried using oven dryers at 50 °C, 60 °C, and 70 °C, as well as a freeze dryer. The leaves were then extracted using 50% and 70% aqueous ethanol and 100% aqueous solutions. The results showed that the highest contents of TPC and TFC were observed when 70% aqueous ethanol was used during freeze drying, reaching 181.73 mg GAE/g dw and 78.57 mg CE/g dw, respectively. The strongest correlations were observed between the TFC and DPPH radical scavenging activity (0.9082), followed by TPC and ABTS assays (0.8933) and TPC and DPPH (0.8272). In the FTIR analysis, freeze drying exhibited a lower intensity of the phenolic -OH functional groups, contrasting with significant denaturation observed during oven drying at 70 °C. Metabolite analysis identified 29 compounds in V. sinaiticum leaves, further confirming the presence of 14 phenolic and flavonoid compounds, including kaempferol, catechin, gallic acid, and myricetin derivatives, consistent with the experimentally observed antioxidant capacity. This study highlights the impact of drying methods on the bioactive composition of V. sinaiticum and underscores its potential as a source of antioxidants for food, nutraceutical, and pharmaceutical applications.

Phytochemical screening and GC-FID identification of bioactive compounds in n-hexane, ethylacetate and methanol fractions of methanolic leaves extract of Azanza garckeana

Azanza garckeana is a tropical African plant commonly used for food and medicine. This study was aimed at evaluating the antioxidant, phytochemicals and the bioactive compounds present in n-hexane, ethylacetate and methanol fractions of the methanolic extract of Azanza garckeana leaves. Phytochemical screening and antioxidant assayed were carried out using standard methods, while bioactive compounds were analyzed using gas chromatography-flame ionization detector (GC-FID). The phytochemical compositions revealed considerable level of tannins and saponins with moderate concentration of flavonoids and steroids in the methanol fraction; whereas n-hexane fraction also showed considerable amount of tannins followed by saponins and a low concentration of steroids. However, ethylacetate fraction had the highest yield of tannins, steroids, and terpenoids which were significantly (p < 0.05) higher than methanolic fraction and n-hexane fraction respectively. The antioxidant activity of the methanolic crude extract of A. garckeana leaves showed that the % DPPH radical scavenging activity of the crude extract increased with decreased in concentration when compared with the standard antioxidant (ascorbic acid). The result of GC-FID analysis revealed the presence of nineteen constituents in n-hexane fraction, while ethylacetate and methanol fractions each have twenty constituents. This result showed that Azanza garckeana leaves contain health-promoting bioactive compounds with potent antioxidants.

Design, synthesis, and characterization of M(II)-Schiff base complexes containing 3,5-di-tert-butyl salicylaldehyde: DNA binding/cleavage, DPPH radical scavenging activity, cytotoxic activity, and catalytic activity investigation

Two mononuclear Cu(II) and Zn(II) based complexes were synthesized via microwave-assisted method utilizing Schiff base ligand based on 3,5-di-tertbutylsalicylaldehyde. The compounds were characterized using elemental and spectroscopic analysis methods. The ligand posed as an ON-donor ligand, confirmed by spectrum analysis in the complexes. A geometry optimization analysis was also performed using density functional theory to obtain the geometry, stability, and electronic properties of the synthesized compounds. CuL1 has a distorted square planar geometry, whereas ZnL1 has a distorted tetrahedral geometry. Fluorescence and absorbance spectroscopy were utilized to explore the interaction properties of calf thymus-deoxyribonucleic acid (CT-DNA) with the complexes. The CuL1 and ZnL1 are highly sensitive to DNA binding, with binding constant (Kb) in the range of 105 M−1, representing substantial interaction with CT-DNA, combining intercalation and electrostatic interactions. The Stern-Volmer constant (Ksv) obtained from the fluorescence spectroscopy method varied from 3.31 x 104 to 8.42 x 104 M−1, indicating moderate DNA binding. Circular dichroism spectroscopy confirmed the presence of intercalative binding among the DNA and the complexes. The in-vitro DNA cleavage activity revealed that complexes could efficiently break the supercoiled plasmid DNA without using any external agents. The complex CuL1 induced significant cytotoxicity for Dalton’s lymphoma cancer cell lines, having IC50 values of 18.96 ± 0.021 μM. The antioxidant activity of the compounds was also studied, confirming CuL1 to be the most active antioxidant with IC50 = 399.27 µM. A molecular docking simulation was also conducted to comprehend the compounds' interaction mechanism with CT-DNA (1BNA) and cancer cells (BCL-family proteins). Furthermore, the catalytic activity of the zinc metal complex was assessed for multi-component reactions involving substituted benzaldehydes, malononitrile, and resorcinol.

Comprehensive analysis of Mentha longifolia subsp. himalaiensis essential oil: GC MS profiling and biological properties

Mentha longifolia is a well-known species of medicinal plant for its ethnopharmacological, pharmacological importance, industrial uses etc. This research paper presents a comprehensive study on a new species Mentha longifolia subsp. himalaiensis essential oil, focusing on its GC-MS analysis, nematicidal and antioxidant activities, as well as in-silico PASS prediction. The essential oil was extracted from Mentha longifolia subsp. himalaiensis leaves using steam distillation and subjected to gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) analysis to identify its chemical composition. The in vitro nematicidal activities were accessed via nematode mortality assay and nematode egg hatching assay against Meloidogyne incognita. The essential oil was also tested for its antioxidant activities via DPPH (2,2-diphenyl-2-picrylhydrazyl) radical scavenging activity, H2O2 (Hydrogen peroxide) scavenging activity and Metal chelating activity. The essential oil was also tested for antimicrobial potential against 5 strains of bacteria and two strains of fungus. Furthermore, the major chemical constituents of the essential oils were subjected to in-silico PASS prediction for their biological activities. The GC and GC-MS analysis revealed that piperitenone oxide (31.13 %) and cis-piperitone oxide (51.61 %) were the major components of the essential oil. The essential oil exhibited significant nematicidal activity against M. incognita and notable antioxidant activity. The essential oils also showed significant antibacterial and antifungal activity against targeted microbial strains. In-silico PASS prediction further supported the essential oil's bioactive properties and its potential for diverse applications. These results highlight the potential of Mentha longifolia subsp. himalaiensis essential oil as a natural nematicide, antimicrobial and antioxidant agent.

Assessment of the catalytic and biological potential of yttrium and samarium-modified copper ferrite nanomaterials

The present study reports the preparation of crystalline and nanosized copper ferrite (CuFe2O4), Y3+ substituted CuFe2O4 (CuFe1.95Y0.05O4), and Sm3+ substituted CuFe2O4 (CuFe1.95Sm0.05O4) using a simple co-precipitation method. The XRD analysis confirmed the formation of the cubic spinel phase, while XPS studies validated the presence of Cu and Fe in 2+ and 3+ oxidation states respectively. Transmission electron microscopy (TEM) analysis revealed the nanoparticles with a diameter in the range of 10–60 nm. The introduction of fractional amounts of Y3+ and Sm3+ ions in the CuFe2O4 lattice enhanced the reduction of 4-nitrophenol, attributed to decreased particle size facilitating the reduction process. In the case of antimicrobial activity, Candida albican was found to be maximally sensitive to CuFe2O4 and CuFe1.95Y0.05O4, while Pseudomonas aeruginosa was inhibited by CuFe1.95Sm0.05O4. Moreover, a maximum of 61.9 ± 1.91 % anti-Pseudomonas biofilm activity and 75.7 ± 1.28 % DPPH radical scavenging activity was observed for CuFe1.95Y0.05O4 at 200 μg/ml concentration. The improvement in biological activities was attributed to the reduced particle size, crystal structure modification, and increased stability of the CuFe2O4 lattice with substitution. The enhancement in catalytic and biological performance highlighted the effectiveness of minimal Y3+ and Sm3+ concentrations in modulating the properties of CuFe2O4 nanomaterials.

The interaction between lipid oxidation and the Maillard reaction model of lysine-glucose on aroma formation in fragrant sesame oil

The formation mechanism behind the sophisticated aromas of sesame oil (SO) has not been elucidated. The interaction effects of the Maillard reaction (MR) and lipid oxidation on the aroma formation of fragrant sesame oil were investigated in model reaction systems made of l-lysine (Lys) and d-glucose (Glc) with or without fresh SO (FSO) or oxidized SO (OSO). The addition of OSO to the Lys-Glc model increased the MR browning at 294 nm and 420 nm and enhanced the DPPH radical scavenging activity greater than the addition of FSO (p < 0.05). The presence of lysine and glucose inhibited the oxidation of sesame oil, reduced the loss of γ-tocopherol, and facilitated the formation of sesamol (p < 0.05). The Maillard-lipid interaction led to the increased concentrations of some of the alkylpyrazines, alkylfurans, and MR-derived ketones and acids (p < 0.05) while reducing the concentrations of other pyrazines, lipid-derived furans, aliphatic aldehydes, ketones, alcohols, and acids (p < 0.05). The addition of FSO to the MR model enhanced the characteristic roasted, nutty, sweet, and fatty aromas in sesame oil (p < 0.05), while excessive lipid oxidation (OSO) brought about an unpleasant oxidized odor and reduced the characteristic aromas. This study helps to understand the sophisticated aroma formation mechanism in sesame oil and provides scientific instruction for precise flavor control in the production of sesame oil.

Effects of Extraction Methods on the Physicochemical Properties and Biological Activities of heteroglycans from Hibiscus sabdariffa calyx

The hot-water extraction method has been employed to enhance the diffusion rate of heteroglycans, thereby augmenting the extraction efficiency. This study investigates the antioxidant activities and immunological properties of water-soluble polysaccharides derived from the Hibiscus sabdariffa calyx (HWPF and LWPF). These polysaccharides were isolated through two distinct extraction methods involving hot water followed by ethanol precipitation. The physicochemical characterization was conducted through a series of experiments encompassing monosaccharide composition, ultraviolet-visible spectrum analysis, and Fourier-transform infrared (FT-IR) spectroscopy. The evaluation of antioxidative properties employed various techniques, including DPPH and ABTS radical scavenging activities, Ferric Reducing Antioxidant Power, ferrous chelating power, total reducing power, and protection against DNA damage. The assessment of anti-inflammatory potential involved the inhibition of hemolytic activity induced by a hypotonic solution and heat. Furthermore, the impact of the polysaccharides on the production of pro-inflammatory cytokines was analyzed through Luminex assay and RTPCR assay in PBMCs and LPS-stimulated RAW 264.7 cells, respectively. The findings revealed that heteroglycans (LWPF and HWPF) exhibit a content of Ara-Man-Rha-GluA-GalA (41.2:17.2:15.7:9.2:8.8) and Ara-Glu-Rha-Xyl-GluA-Man (31.5:23.8:12.16:10.4:7:6) with molecular weights of approximately 4.5 KDa and 41.3 KDa, respectively. HWPF demonstrated robust metal chelating and scavenging activities. Additionally, each fraction exhibited substantial protection of DNA against damage induced by H2O2. LWPF was observed to significantly down-regulate the expression of pro-inflammatory cytokines IL-6 and COX-2 at both transcriptional and translational levels, along with inhibiting NO production. In summary, these results indicate that the choice of extraction methods influences both the structure and biological activities of heteroglycans, providing valuable insights into the structure-activity relationship.&#x0D; Keywords: Hibiscus sabdariffa, heteroglycans, hot water extraction, physicochemical properties, Antioxidant activity, Pro-inflammatory cytokines.

Effects of Drying Methods on the Antioxidant Properties of Piper betle Leaves.

Piper betle leaf powder is increasingly utilised as a health supplement. In this study, P. betle leaves were subjected to four different drying methods: convective air-drying, oven-drying, sun-drying, and no drying, with fresh leaves as control. Their antioxidant properties were then evaluated using colourimetric assays and GC-MS. Results showed that the sun-dried leaves had the highest (p < 0.05) total antioxidant capacity (66.23 ± 0.10 mg AAE/g), total polyphenol content (133.93 ± 3.76 mg GAE/g), total flavonoid content (81.25 ± 3.26 mg CE/g) and DPPH radical scavenging activity (56.48 ± 0.11%), and the lowest alkaloid content (45.684 ± 0.265 mg/gm). GC-MS analysis revealed that major constituents of aqueous extracts of fresh and sun-dried P. betle leaves were hydrazine 1,2-dimethyl-; ethyl aminomethylformimidate; glycerin; propanoic acid, 2-hydroxy-, methyl ester, (+/-)-; and 1,2-Cyclopentanedione. In conclusion, sun-dried leaves exhibited overall better antioxidant properties, and their aqueous extracts contained biologically active phytoconstituents that have uses in various fields.

Improving Soluble Phenolic Profile and Antioxidant Activity of Grape Pomace Seeds through Fungal Solid-State Fermentation.

Grape pomace seeds contain abundant phenolic compounds, which are also present in both soluble and insoluble forms, similar to many other plant matrices. To further increase the extractable soluble phenolics and their antioxidant activities, grape pomace seeds were fermented with different fungi. Results showed that solid-state fermentation (SSF) with Aspergillus niger, Monascus anka, and Eurotium cristatum at 28 °C and 65% humidity had a significantly positive impact on the release of soluble phenolics in grape pomace seeds. Specifically, SSF with M. anka increased the soluble phenolic contents by 6.42 times (calculated as total phenolic content) and 6.68 times (calculated as total flavonoid content), leading to an overall improvement of antioxidant activities, including DPPH (increased by 2.14 times) and ABTS (increased by 3.64 times) radical scavenging activity. Furthermore, substantial changes were observed in the composition and content of individual phenolic compounds in the soluble fraction, with significantly heightened levels of specific phenolics such as chlorogenic acid, syringic acid, ferulic acid, epicatechin gallate, and resveratrol. Notably, during M. anka SSF, positive correlations were identified between the soluble phenolic content and hydrolase activities. In particular, there is a strong positive correlation between glycosidase and soluble phenols (r = 0.900). The findings present an effective strategy for improving the soluble phenolic profiles and bioactivities of grape pomace seeds through fungal SSF, thereby facilitating the valorization of winemaking by-products.