Free Radical Scavenging Ability Research Articles

Optimization of Flavonoid Extraction from Abelmoschus manihot Flowers Using Ultrasonic Techniques: Predictive Modeling through Response Surface Methodology and Deep Neural Network and Biological Activity Assessment.

Understanding the optimal extraction methods for flavonoids from Abelmoschus manihot flowers (AMF) is crucial for unlocking their potential benefits. This study aimed to optimize the efficiency of flavonoid extraction from AMF. After comparing extraction methods, the ultrasonic cell crusher demonstrated superior performance over conventional techniques. Four key factors-solid-to-liquid ratio (1:10 to 1:50 g·mL-1), ethanol concentration (55% to 95%), ultrasonic time (10 to 50 min), and ultrasonic power (5% to 25% of 900 W)-were investigated and normalized using the entropy weight method. This led to a comprehensive evaluation (CE). Optimization of extraction conditions for the ultrasonic cell crusher was achieved through response surface methodology and a deep neural network model, resulting in optimal parameters: ethanol volume fraction of 66%, solid-to-liquid ratio of 1:21 g/mL, extraction efficiency of 9%, and extraction duration of 35 min, yielding a CE value of 23.14 (RSD < 1%). Additionally, the inhibitory effects of the optimized extracts against Streptococcus mutans (S. mutans) were assessed. The results revealed that AMF extract (AMFE) exhibits inhibitory effects on S. mutans, with concomitant inhibition of sucrase and lactate dehydrogenase (LDH). The MIC of AMFE against planktonic S. mutans is 3 mg/mL, with an MBC of 6 mg/mL. Within the concentration range of 1/8 MIC to 2 MIC of AMFE, the activities of sucrase and LDH decreased by 318.934 U/mg prot and 61.844 U/mg prot, respectively. The antioxidant activity of AMFE was assessed using the potassium ferricyanide reduction and phosphomolybdenum methods. Additionally, the effect of AMFE on DPPH, ABTS, and ·OH free radical scavenging abilities was determined. The concentrations at which AMFE exhibited over 90% scavenging rate for ABTS and DPPH free radicals were found to be 0.125 mg/mL and 2 mg/mL, respectively.

Intervention effects of low-molecular-weight chondroitin sulfate from the nasal cartilage of yellow cattle on lipopolysaccharide-induced behavioral disorders: regulation of the microbiome-gut-brain axis.

Chondroitin sulfate (CS) is a sulfated linear polysaccharide with different functional activities, including antioxidant, anti-inflammatory, lipid-lowering, and immune regulation. As natural sulfated polysaccharides have high molecular weight, high apparent viscosity, low water solubility, complex structure, and high negative charge, they have difficulty binding to receptors within cells across tissue barriers, resulting in low bioavailability and unclear structure-activity relationships. In this study, an H2O2-Vc oxidative degradation system was employed to perform environmentally friendly and controllable degradation of CS extracted from the nasal cartilage of Shaanxi Yellow cattle. Two low-molecular-weight chondroitin sulfates (LMWCSs), CS-1 (14.8 kDa) and CS-2 (50.9 kDa), that exhibit strong in vitro free radical scavenging ability were obtained, and their structures were characterized. Mice intraperitoneally administered lipopolysaccharide (LPS) were used to explore the cognitive intervention effects of LMWCS. Supplementing CS-1 and CS-2 significantly downregulated the levels of the serum inflammatory factors, TNF-α and IL-1β, promoted the expression of GSH in the brain, and inhibited the production of the lipid peroxidation product, malondialdehyde (MDA), ultimately inhibiting LPS-induced cognitive impairment in mice. Surprisingly, compared to the LPS model group, the abundances of Streptococcus, Eisenbergiella, Vampirovibrio, Coprococcus, Enterococcus and Lachnoanaerobaculum were significantly increased in the intestines of mice in the CS-1 and CS-2 group, whereas those of Parabacteroides and Mycoplasma were significantly decreased. Altogether, this study provides a theoretical basis for the comprehensive utilization of agricultural and animal resources and the application of brain nutrition, anti-inflammatory, and LMWCS health products.

Evaluation of Free Radical Scavenging Ability of Triazole-3-Thiol: A Combination of Experimental and Theoretical Approaches

Evaluation of Free Radical Scavenging Ability of Triazole-3-Thiol: A Combination of Experimental and Theoretical Approaches

Lactic acid bacteria fermentation improves physicochemical properties, bioactivity, and metabolic profiles of Opuntia ficus-indica fruit juice

Lactic acid bacteria (LAB) fermentation has been proven to promote human health. The effect of different LAB fermentation on the quality of Opuntia ficus-indica fruit juice (OFIJ) was investigated. OFIJ was an excellent substrate for fermentation, with colony counts of more than 8 log CFU/mL after fermentation. The fermentation altered the acid and sugar contents. Simultaneously, the total phenolic and anthocyanin contents significantly increased. Antioxidant activity enhanced significantly in Lactiplantibacillus plantarum HNU082-fermented OFIJ, primarily in ABTS+ (increased by 16.81%) and DPPH (increased by 23.62%) free radical scavenging ability. Lacticaseibacillus paracasei HNU502-fermented OFIJ showed the most potent inhibition of xanthine oxidase (IC50 = 31.01 ± 3.88 mg TAC/L). Analysis of volatile and non-volatile compounds indicated that fermentation changed the flavor quality and metabolic profiles and caused the most significant modifications in amino acid metabolism. These findings offer valuable information into processing of OFIJ, making it a great choice for functional foods.

Soluble Dietary Fiber from Citrus unshiu Peel Promotes Antioxidant Activity in Oxidative Stress Mice and Regulates Intestinal Microecology

Aging is characterized by the progressive degeneration of bodily tissues and decline in physiological functions, a process that may be exacerbated by imbalances in intestinal flora. Soluble dietary fiber (PSDF) from Citrus unshiu peel has demonstrated strong free radical scavenging ability to regulate intestinal flora in vitro. However, further evidence is required to ascertain the effectiveness of PSDF in vivo. In our study, 8-week-old mice were artificially aged through subcutaneous injections of a 200 mg/kg/d D-galactose solution for 42 days, followed by a 28-day dietary intervention with varying doses of PSDF, insoluble dietary fiber (PIDF), and vitamin C. After the intervention, we observed a significant mitigation of D-galactose-induced oxidative stress, as evident by weight normalization and reduced oxidative damage. 16S rRNA gene sequencing revealed that PSDF significantly altered the composition of intestinal flora, increasing Firmicutes and reducing Bacteroidota percentages, while also enriching colonic short-chain fatty acids (SCFAs). Spearman correlation analysis further identified a positive correlation between Firmicutes and isovaleric acid, and negative correlations between Muribaculaceae and acetic acid, and between Lachnospiraceae_NK4A136_group and caproic acid. These findings support the potential of Citrus PSDF to alleviate oxidative stress.

Direct electrospinning for producing multiple activity nanofibers consisting of aggregated luteolin/hydroxypropyl-gamma-cyclodextrin inclusion complex

Hydroxypropyl-gamma-cyclodextrin (HPγCD) inclusion complex nanofibers (Lut/HPγCD-IC-NF) containing Luteolin (Lut) were prepared by electrospinning technology. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) spectra confirmed the formation of Lut/HPγCD-IC-NF. Scanning electron microscopy (SEM) images showed that the morphology of Lut/HPγCD-IC-NF was uniform and bead-free, suggesting that self-assembled aggregates, macromolecules with higher molecular weights, were formed by strong hydrogen bonding interactions between the cyclodextrin inclusion complexes. Confocal laser scanning microscopy (CLSM) images showed that Lut was distributed in Lut/HPγCD-IC-NF. Proton nuclear magnetic resonance (1H NMR) spectroscopy revealed the change in chemical shift of the proton peak between Lut and HPγCD, confirming the formation of inclusion complex. Thermogravimetric analysis (TGA) proved that Lut/HPγCD-IC-NF had good thermal stability. The phase solubility test confirmed that HPγCD had a solubilizing effect on Lut. When the solubility of HPγCD reached 10 mM, the solubility of Lut increased by 15-fold. The drug loading test showed that the content of Lut in fibers reached 8.57 ± 0.02 %. The rapid dissolution experiment showed that Lut/HPγCD-IC-NF dissolved within 3 s. The molecular simulation provides three-dimensional evidence for the formation of inclusion complexes between Lut and HPγCD. Antibacterial experiments showed that Lut/HPγCD-IC-NF had enhanced antibacterial activity against S. aureus. Lut/HPγCD-IC-NF exhibited excellent antioxidant properties with a free radical scavenging ability of 89.5 ± 1.1 %. In vitro release experiments showed Lut/HPγCD-IC-NF had a higher release amount of Lut. In conclusion, Lut/HPγCD-IC-NF improved the physicochemical properties and bioavailability of Lut, providing potential applications of Lut in the pharmaceutical field.

Deciphering the binding mechanisms of eugenol and 2-methylpyrazine with human serum albumin using technical approach

Eugenol (EGL) and 2-methylpyrazine (2-MTP) are common food additives that are used as flavors in a variety of foods. To study the effect of food additives on human serum albumin (HSA), it is necessary to deeply study the interaction of EGL and 2-MTP with HSA. Fluorescence, UV–vis absorption, circular dichroism (CD) and computational techniques showed EGL and 2-MTP bind statically to HSA, inducing conformational changes of HSA. We calculated the quenching constants (ksv), binding constants (kq), binding distances (r) and thermodynamic constants (ΔH0, ΔS0, ΔG0) at four different temperatures. Based on thermodynamic analysis and molecular dynamics (MD) simulations, the main forces of 2-MTP-HSA and EGL-HSA systems are hydrophobic interaction and π-π accumulation, respectively. In addition, the interaction alters the physiological activity of HSA, esterase activity and free radical scavenging ability. This study provides valuable insights into the molecular interactions of food additive compounds EGL and 2-MTP with HSA, the findings provide theoretical reference for the development of new food additives and drugs in the future.

Melanin nanoparticles scavenging reactive oxygen and nitrogen radicals for rheumatoid arthritis treatment

Rheumatoid arthritis (RA) is a complex and chronic disease that often causes long-term pain and joint swelling in patients, and even causes joint deformity and dysfunction. The pathogenesis of this disease involves abnormal activity of the immune system, causing immune cells to attack the bodys joint tissues, which triggers an inflammatory response. During these inflammatory processes, the accumulation of reactive oxygen and nitrogen species (RONS) is considered to be one of the key factors that aggravate inflammation and damage joint tissues. To address this problem, we designed a method that takes advantage of the targeting properties of melanin nanoparticles. These nanoparticles have excellent biocompatibility, can remain stable in the body, and can be accurately targeted to the site of inflammation. In addition, these nanoparticles also have strong free radical scavenging ability, which can effectively neutralize excessive RONS, reduce the inflammatory response and weaken joint tissue damage. The promise of this treatment strategy is encouraging and offers new hope for patients with RA. By reducing inflammation, protecting joint tissue, and possibly even reversing the disease process to some extent, this melanin nanoparticle holds great promise.

Phytochemical screening, antibacterial, antioxidant, and cytotoxic activities of Geranium pusillum leaves.

Traditional medicinal plants play an important role in primary health care worldwide. The phytochemical screening and activities of Geranium pusillum were investigated in this research. The dried plant leaves were extracted with ethanol, n-hexane, chloroform, dichloromethane, methanol, acetone, and aqueous solvents. These extracts were qualitatively analyzed, GC-MS, antimicrobial activities by using the disc diffusion method, antioxidant activity was determined by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging, and cytotoxic activity was analyzed by the hemolytic activity of human red blood cells. The results showed phytochemicals such as flavonoids, terpenoids, steroids, phenols, saponins, tannins, and cardiac glycosides were detected in plant leaves. The ethanol extract at a concentration of 10 mg/mL showed a maximum inhibition zone 17.5 ± 0.09, 15.6 ± 0.11, 14.2 ± 0.17, 18.4 ± 0.11, 16.6 ± 0.15, 12.5 ± 0.13, 15.9 ± 0.10, and 13.1 ± 0.11 mm, and at 15 mg/mL showed 24.5 ± 0.09, 27.2 ± 0.12, 26.3 ± 0.17, 28.4 ± 0.10, 27.9 ± 0.16, 22.5 ± 0.13, 27.1 ± 0.10, and 24.1 ± 0.16 mm against Escherichia coli, Pasturella multocida (gram-negative), Staphylococcus aureus, Bacillus subtilus (gram-positive), Rhizopus solani, Aspergillus flavus, Aspergillus niger, and Alternaria alternate (fungal strain), respectively, and dichloromethane showed a minimum inhibition zone as compared to other extracts against bacterial as well as fungal strains. Chloroform extract had maximum antioxidant activity (45.00 ± 0.08%) and minimum in dichloromethane (12.20 ± 0.04%). Cytotoxic activity was found maximum in acetone extract (19.83 ± 0.07%) and minimum in ethanol extract (4.72 ± 0.04%). It is concluded that phytochemicals like phenols, flavonoids, and others may be responsible for these activities, which is why this plant is used for traditional medicine. RESEARCH HIGHLIGHTS: Geranium pusillum has therapeutic properties that exhibit various biological activities beneficial for human health. G. pusillum has significant inhibitory effects against bacterial and fungal strains. Chloroform solvent extract indicates potential free radical scavenging abilities. Acetone extract exhibits notable effects on human red blood cells and demonstrates significant cytotoxic activity.

Thermal stability, antioxidant activity and bioavailability of pea protein–naringin Pickering emulsion for enhanced delivery applications

After successfully addressing to mitigate bitterness of naringin through construction Pickering emulsion using pea protein (PP) and naringin (NG) in our previous study, we now probed thermal stability, antioxidant efficacy, and bioavailability. FTIR analysis and UV–vis spectroscopy indicated predominant interactions between PP and NG were hydrogen and hydrophobic bonds. TGA and DSC analyses demonstrated that PP-NG complexes exhibited superior heat-resistance compared to pure PP and NG. Thermal stability assessments indicated a significant retention of NG in the PP-NG Pickering emulsion than the control NG across varied temperatures (4 °C, 25 °C, 37 °C, and 65 °C). Moreover, the antioxidant activity of PP-NG emulsion was dependent on the concentration of NG, as evidenced by DPPH and ABTS free radicals scavenging abilities, ferric reducing power, and lipid peroxidation resistance. Additionally, PP-NG Pickering emulsion exhibited substantially high bioavailability (92.01 ± 3.91%). These results suggest a promising avenue for the application of NG with improved characteristics.

Agro-waste mediated silver nanoparticles from Pithecellobium dulce (Roxb.) Benth fruit peel and their multifaceted biomedical applications

The present work aimed to produce silver nanoparticles using an agro-waste fruit peel extract from Pithecellobium dulce (Roxb.) Benth (PD) and examine their antibacterial, antioxidant, and anticancer characteristics. The synthesized silver nanoparticles (PD-AgNPs) were validated by the characteristic dark brown hue and surface plasmon resonance at 417 nm. Fourier transform infra-red spectrum pinpoints the important functional groups in charge of their reduction and capping. The X-ray diffraction pattern and transmission electron microscopic images confirmed the face-centred cubic crystal structure and spherical-shaped PD-AgNPs. Particle size and stability of the PD-AgNPs were found to be 83.90 and −31.2 mV respectively. Antibacterial experiments against E. coli, K. pneumoniae, B. subtilis, and S. aureus showed concentration-dependent inhibitory effects. In various assays, including those for DPPH, hydroxyl, superoxide anions, and ABT radicals, PD-AgNPs exhibited strong free radical scavenging abilities when compared with vitamin C. In the MTT experiment, PD-AgNPs displayed dose-dependent cytotoxicity against MG-63 cells with an IC50 of 22.09 µg/mL. Additionally, the anticancer potential of PD-AgNPs was studied by measuring mitochondrial membrane potential and apoptosis. The potential of PD-AgNPs for utilization in biomedical applications was established by their antibacterial, antioxidant, and anticancer characteristics. The study emphasizes the importance of green synthesis methodologies in creating multifunctional nanoparticles with therapeutic potential, which warrants further investigation for practical medical applications.

Theoretical Study of Radical Scavenging Antioxidant Activity of Coumarin Derivatives in Licorice Using DFT

Nowdays, much research is focused on exploring antioxidant activity based on natural compounds. Licorice, a traditional natural product rich in antioxidant components, has been widely used in clinical medicine. However, there is a lack of theoretical studies on the active components in licorice. In this context, the antioxidant activity of several common active components of coumarin derivatives in licorice was investigated using a density flooding theory (DFT) approach. The free radical scavenging ability of the compounds was achieved by hydrogen atom transfer (HAT), sequential electron transfer proton transfer (SET-PT) and sequential proton loss electron transfer (SPLET) mechanisms. The effect of solvent on antioxidant activity was also investigated. It was found that in the gas and benzene phases, the compounds studied preferred to undergo the HAT mechanism, while SPLET was favoured in polar solvents. In addition to the above mechanism, the HOMO and LUMO energies of the compounds as well as molecular descriptors and electrostatic potential maps were calculated and applied to predict the antioxidant activity of the compounds. The above studies allow a better understanding of the mechanism of free radical scavenging activity of coumarin derivatives from licorice.

Different wavelengths of LED irradiation promote secondary metabolite production in Pycnoporus sanguineus for antioxidant and immunomodulatory applications.

Pycnoporus sanguineus is a fungus of the phylum Basidiomycota that has many applications in traditional medicine, modern pharmaceuticals, and agricultural industries. Light plays an essential role in the metabolism, growth, and development of fungi. This study evaluated the mycelial growth and antioxidant and anti-inflammatory activities in P. sanguineus fermentation broth (PFB) cultured under different wavelengths of LED irradiation or in the dark. Compared to the dark cultures, the dry weight of mycelia in red- and yellow-light cultures decreased by 37 and 35% and the yields of pigments increased by 30.92 ± 2.18mg and 31.75 ± 3.06mg, respectively. Compared with the dark culture, the DPPH free radical scavenging ability, ABTS+ free radical scavenging capacity, and reducing power of yellow-light cultures increased significantly, and their total phenolic content peaked at 180.0 ± 8.34μg/mL. However, the reducing power in blue-light cultures was significantly reduced, though the total phenol content did not vary with that of dark cultures. In LPS- and IFN-γ-stimulated RAW 264.7 cells, nitrite release was significantly reduced in the red and yellow light-irradiated PFB compared with the dark culture. In the dark, yellow-, and green-light cultures, TNF-α production in the inflamed RAW 264.7 cells was inhibited by 62, 46, and 14%, respectively. With red-, blue-, and white-light irradiation, TNF-α production was significantly enhanced. Based on these results, we propose that by adjusting the wavelength of the light source during culture, one can effectively modulate the growth, development, and metabolism of P. sanguineus.

Protein identification and potential bioactive peptides from pumpkin (Cucurbita maxima) seeds

AbstractPumpkin is an economically important crop all over the world. Approximately, 18%–21% of pumpkins, consisting of peels and seeds by‐products, are wasted during processing. In addition, the seeds are rich in protein and have the potency of bioactive peptide production. This study aims to recognize the proteins and investigate the potential bioactive peptides from pumpkin (Cucurbita maxima) seeds. Pumpkin seeds were subjected to hot air drying (HAD) at 55°C for 12 h and freeze‐drying (FD) at −80°C for 54 h before they were powdered, analyzed, and precipitated by isoelectric point to obtain pumpkin seed protein isolates (PSPI). PSPI comprised 11S globulin subunit beta, 2S seed storage albumin, and chaperonin CPN60‐1. To generate hydrolysate peptides, PSPI was hydrolyzed using papain, pepsin, and bromelain. FD group pepsin hydrolysates had the highest peptide content of 420.83 mg/g. ACE inhibition and DPP‐IV inhibition activity were analyzed for each enzymatic hydrolysate. The pepsin hydrolyzed sample exhibited the highest ACE inhibition of 70.26%, and the papain hydrolyzed sample exhibited the highest DPP‐IV inhibition of 30.51%. The simulated gastrointestinal digestion (SGID) conducted by pepsin and pancreatin increased ACE inhibitory activity from 76.93% to 78.34%, and DPP‐IV inhibited activity increased from 58.62% to 77.13%. Pepsin and papain hydrolysates were fractionated using ultrafiltration to measure ACE and DPP‐IV inhibition activity. The highest free radical scavenging abilities were exhibited by the &lt;1 kDa hydrolysate fractions with 78.34% ACE inhibitory activities and 79.55% DPP‐IV inhibitory activities. This research revealed that pumpkin seeds had the potency to produce bioactive peptides.

Polyphenolic contents and antioxidant potential in Nasturtium officinale

The present study was conducted with the aim to assess the impact of environmental conditions on polyphenolic content and free radical scavenging ability in the leaves of N. officinale used as food and medicine in the Himalayan region of Pakistan. Samples were gathered from six different sites located in Himalaya, Hindukush, and Karakorum ranges. Polyphenolic profiling, and in vitro antioxidant potential were determied using standard analytical techniques. The samples collected from Abbottabad had significnat levels (p≤0.05) of total phenolic (331.43±41.43 mg GAE/100g DW) and total flavonoid contents (8.45±1.53 mg RutE/100g DW). Whereas, rutin, quercitin and kaempferol were maximum in samples collected from Dir(132.46±0.31, 8.80±0.05 and 0.95±0.04 µg/g, respectively). Likewise, Gallic and caffeic acids were highest in Haripur and Swat samples, whereas ferulic and p-coumaric acids were maximum in samples taken from Dir. The percentage scavenging of DPPH was maximum in samples collectded from Chitral (69.57±3.39%) and that of H2O2 at Dir (57.24±8.05%), whereas samples collected from Abbottabad depicted maximum inhibition of ferric and molybdate ions. Total phenolic and total flavonoids contents exhibited highly significant positive correlations (p≤0.01) with ferric and molybdate ions reduction capacity. Cluster and principal component analyses also depicted significant associations among samples collected from Abbottabad-Haripur, Dir-Swat, and Mansehra-Chilas. Our findings contribute in understanding the antioxidant potential of N. officinale leaves, and highlights the importance of polyphenolic composition and environmental factors in future investigations related to its nutraceutical applications. Further research on detailed phytochemcial profiling, their in vitro and in vivo mechanisms of action could unveil the potential of this plant as a functional food.

Effects of different amounts of okara on texture, digestive properties, and microstructure of noodles.

As a byproduct of manufacturing soybeans, okara is high in dietary fiber, protein, and fats, and it contains all of the essential amino acids. Wheat, the primary ingredient in noodles, will lose nutrients during manufacturing, creating an imbalance in nutrients. This experiment is for the purpose of studying the effects of okara on quality, antioxidant properties, amino acid content, resistant starch (RS) content, and microstructure of noodles. The results indicate that the addition of 9% okara noodles increased hardness and adhesiveness by 107.19% and 132.14%, respectively, and improved ABTS free radical scavenging activity by 60.78%. The addition of 12% okara noodles increased the DPPH free radical scavenging ability by 23.66%, reduced the rapidly digestible starch (RDS) content of the noodles to 21.21%, and the resistant starch content increased to 44.85% (p < .05). Therefore, to address the issue of nutritional imbalance in wheat noodles without compromising the quality of the noodles, it is recommended to add 9% or 12% okara for the preparation of nutritionally fortified noodles.

Antioxidant capacity, anti-inflammatory activity, and mutagenicity of Sterculia lychnophora (Pangdahai) polysaccharide

Dried boat-fruited ripped seeds of Sterculia lychnophora, commonly known as Pangdahai, are frequently used in traditional Chinese medicines and functional foods. However, research on these constituents is limited. In this study, the extraction of Pangdahai polysaccharide (PP) was investigated using different solvents (deionized water, 50 % methanol, and 50 % ethanol), and its chemical composition, antioxidant capacity, and anti-inflammatory activity were analyzed. Additionally, the Ames test was used to evaluate PPs’ food safety and mutagenicity. The results showed that the yields of PPs extracted with the three solvents ranged from ∼ 19 % to 21 % and that their monosaccharide compositions (rhamnose, arabinose, galactose, and glucose) were similar, with slightly different proportions. Moreover, the antioxidant capacity of all three PPs showed concentration-dependent effects. The EC50 values for each antioxidant were approximately 0.71–1.35 mg/mL for 1, 1-diphenyl-2-picrylhydrazyl free radical scavenging ability, 1.88–46.13 µg/mL for 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging ability, 2.22–3.61 mg/mL for ferric reducing antioxidant power, and 0.52–3.11 mg/mL for hydroxyl radical scavenging ability. At concentrations below 500 µg/mL, the anti-inflammator activity of PPs promoted cell proliferation while inhibiting nitric oxide production at concentrations ranging from 31.25 to 125 µg/mL. In the Ames test, PPs (1–5 mg/plate) exhibited no toxicity or mutagenicity against the five strains of Salmonella typhimurium (TA98, TA100, TA102, TA1535, and TA1537). These findings will particularly be of interest to individuals involved in PP-related research or commercial enterprises. Thus, the findings of this study will elucidate the bioactive components and potential benefits of PP, making it especially valuable to researchers and practitioners in the Pangdahai industry and expanding opportunities for industrial development.

Optimization of watermelon peel yogurt fermentation process and study on antioxidant capacity

This study aims to explore the variation patterns of total flavonoid and other antioxidant activities in watermelon peel yogurt, providing a basis for the production of a functional yogurt. Using watermelon peel as the raw material and total flavonoid content as the indicator, the optimal process of watermelon peel yogurt was optimized through single-factor and orthogonal experiments. The results indicate that yogurt fermented with a mass ratio of watermelon juice to milk at 1:3, fermentation time of 10 hours, and fermentation agent dosage of 0.10% exhibits a refreshing watermelon aroma, excellent texture, and almost no whey separation. After process optimization, the polysaccharide content of watermelon peel yogurt increased by 19%, and water-holding capacity rose to 63.3%. Texture analysis revealed a hardness of 81.50 g, viscosity of 20.00 g, adhesiveness of 1.20 mJ, elasticity of 8.83 mm, and a draw length of 6.76 mm. The physicochemical and microbiological properties of watermelon peel yogurt meet national standards, and it possesses a good free radical scavenging ability.

Pulsed electric field treatment improves the oil yield, quality, and antioxidant activity of virgin olive oil

Pulsed electric field (PEF) is an innovative technique used to assist in the extraction of vegetable oils. There has been no research on the effects of PEF on virgin olive oil (VOO) quality and antioxidant activity to date. The present study aimed to analyze the effects of PEF on oil yield, quality, and in vitro antioxidant activity of “Koroneiki” extra virgin olive oil. The results show that the PEF treatment increased the oil yield by 5.6%, but had no significant effect on the saponification value, K232, K270, and ∆K value of the VOO. PEF treatment reduced the oleic acid content by 3.12%, but had no significant effect on the content of palmitic acid, linoleic acid, linolenic acid, arachidonic acid, stearic acid, oleic acid, and palmitic acid. After PEF treatment, the levels of total phenolics, total flavonoids, and oleuropein increased by 7.6%, 18.3% and 76%, respectively. There was no significant effect on the levels of 4 phenolic acids (vanillic acid, p-coumaric acid, ferulic acid and cinnamic acid), 2 lignans (lignans and apigenin), hydroxytyrosol, and 3 pigments (lutein, demagnetized chlorophyll, and carotenoids). In addition, PEF treatment significantly increased the content of tocopherols, with α, β, γ, and δ tocopherols increasing by 9.8%, 10.7%, 13.6% and 38.4%, respectively. The free radical scavenging ability of DPPH and ABTS was also improved. In conclusion, the use of PEF significantly increased the yield of VOO oil as well as the levels of total phenolics, total flavonoids, oleuropein, tocopherol, and in vitro antioxidant activity.

Tea polyphenol-derived nanomedicine for targeted photothermal thrombolysis and inflammation suppression

Thrombotic diseases impose a significant global health burden, and conventional drug-based thrombolytic therapies are encumbered by the risk of bleeding complications. In this study, we introduce a novel drug-free nanomedicine founded on tea polyphenols nanoparticles (TPNs), which exhibits multifaceted capabilities for localized photothermal thrombolysis. TPNs were synthesized through a one-pot process under mild conditions, deriving from the monomeric epigallocatechin-3-gallate (EGCG). Within this process, indocyanine green (ICG) was effectively encapsulated, exploiting multiple intermolecular interactions between EGCG and ICG. While both TPNs and ICG inherently possessed photothermal potential, their synergy significantly enhanced photothermal conversion and stability. Furthermore, the nanomedicine was functionalized with cRGD for targeted delivery to activated platelets within thrombus sites, eliciting robust thrombolysis upon laser irradiation across diverse thrombus types. Importantly, the nanomedicine’s potent free radical scavenging abilities concurrently mitigated vascular inflammation, thus diminishing the risk of disease recurrence. In summary, this highly biocompatible multifunctional nanomaterial holds promise as a comprehensive approach that combines thrombolysis with anti-inflammatory actions, offering precision in thrombosis treatment.