The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay is commonly applied for appraising antioxidant activity of plant extracts. To test the potential interference of borate on DPPH assay, the effects of ...borates (0–16 mM sodium tetraborate) on the DPPH radical scavenging ability of gallic acid (GA, at 10, 20 and 40 mg/L) were studied. The presence of borate led to a remarkable reduction of DPPH inhibition of GA, and its DPPH radical scavenging ability can be suppressed contingently on borate content. This interference was interpreted to be resulted from the autoxidation of GA as well as the formation of GA-borate ester complex under alkaline pH (~9.50) of borate. Natural polyphenol extracts from apple peels, parsley and lettuce leaves (as boron-enriched representatives) also exhibited a reduced ability in eliminating DPPH radicals when spiked with borates. In order to avoid this limitation, the utilization of acetate buffer at pH 5.50 for sample preparation is proposed. This work pointed to the possible underestimation of antioxidant properties of polyphenol extracts originated especially from boron-enriched or borate pretreated plants by DPPH assay.
•Borate interfered with the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay.•DPPH inhibition of gallic acid (GA) was suppressed contingently on borate content.•The oxidation of GA at alkaline pH of borate may cause the reduced DPPH inhibition.•This interference might be also due to the formation of GA-borate ester complex.•The utilization of acetate buffer at pH 5.50 can avoid this limitation.
The present study reports the phyto-mediated synthesis of ZnONPs using methanol extracts and n-Butanol fractions from the roots and leaves of C. oppositifolia. The synthesized nanoparticles were ...characterized using XRD, FE-SEM, HR-TEM, and XPS techniques to determine their crystallite structure, elemental composition, surface topography, and physio-chemical properties. Furthermore, the biological potential of ZnONPs was evaluated for antioxidant, antimicrobial, anti-inflammatory, and in vitro cytotoxic potential on SH-SY5Y neuroblastoma cell lines. Notably, LEME-ZnONPs exhibited exceptional antioxidant activity with an IC50 of 30.200 μg/mL in the DPPH assay. The antimicrobial efficacy was also remarkable, displaying high maximum activity against bacterial strains, evidenced by zones of inhibition (ZOI) measuring 15.67 ± 0.58 mm (E. coli) and 14.67 ± 0.58 mm (S. aureus) for RTME-ZnONPs, attributable to their small crystallite size. Similarly, against antifungal strains, LEBF-ZnONPs (60.94 ± 0.83 %) and RTBF-ZnONPs (60.85 ± 0.74 %) exhibited potency to inhibit both F. oxysporum and R. necatrix due to their small particle size. Furthermore, LEBF-ZnONPs demonstrated superior anti-inflammatory properties, registering an impressive 98.681 %, outperforming Diclofenac sodium (96.835 %). Importantly, the phyto-mediated ZnONPs exhibited minimal cytotoxicity on SH-SY5Y cell lines at 62.5 μg/mL, a concentration employed as an experimental model to assess neuronal function. The multifaceted applications of phyto-mediated ZnONPs extend across various fields, including pharmaceutical sciences, agriculture, and the treatment of neurological diseases.
This graphical abstract indicates the diverse biological potential of phyto-mediated ZnO NPs, from antioxidant competence to antimicrobial successes, and the perfect synergy of anti-inflammatory and neuroprotective actions. Display omitted
•ZnONPs exhibit outstanding antioxidant properties attributed to the incorporation of bioactive phytocompounds on their surface.•Phyto-mediated ZnO NPs demonstrate significant potential against E. coli (15.67 ± 0.58 mm) and F. oxysporum (60.94 ± 0.83 %), ascribed to their lower crystallite size.•Concentrations below 62.5 μg/mL of ZnONPs shows potential against neurological disorders such as epilepsy.
•Simple synthesis route and preparation of biogenic phenolic stabilizers.•Novel antioxidants feature high thermal stability.•Stabilizers are subjected to extrusion under tougher ...conditions.•Comparison of extrusion experiments with radical efficency in DPPH Assay to show a simple pre-test to estimate the performance.
Bio-based molecules show great research potential to achieve alternatives to petrochemically produced products. Therefore, biogenic stabilizers (vanillates, syringates and gallates) were prepared, which were subsequently characterized by various analytical methods. Nuclear magnetic resonance spectroscopy was used for structural elucidation. Thermal stability and thus suitability for polymer processing were confirmed by thermogravimetric measurements. To assess the stabilizing effect, radical efficiency was determined using 2,2-diphenyl-1-picrylhydrazyl assays. Polymer compounds were processed in an extruder as well. In these prolonged extrusion experiments, the stabilizing effect in the melt was revealed.
Environment friendly methods for the synthesis of copper nanoparticles have become a valuable trend in the current scenario. The utilization of phytochemicals from plant extracts has become a unique ...technology for the synthesis of nanoparticles, as they possess dual nature of reducing and capping agents to the nanoparticles. In the present investigation we have synthesized copper nanoparticles (CuNPs) using a rare medicinal plant Cissus arnotiana and evaluated their antibacterial activity against gram negative and gram positive bacteria. The morphology and characterization of the synthesized CuNPs were studied and done using UV-Visible spectroscopy at a wavelength range of 350–380 nm. XRD studies were performed for analyzing the crystalline nature; SEM and TEM for evaluating the spherical shape within the size range of 60–90 nm and AFM was performed to check the surface roughness. The biosynthesized CuNPs showed better antibacterial activity against the gram-negative bacteria, E. coli with an inhibition zone of 22.20 ± 0.16 mm at 75 μg/ml. The antioxidant property observed was comparatively equal with the standard antioxidant agent ascorbic acid at a maximum concentration of 40 μg/ ml. This is the first study reported on C. arnotiana mediated biosynthesis of copper nanoparticles, where we believe that the findings can pave way for a new direction in the field of nanotechnology and nanomedicine where there is a significant potential for antibacterial and antioxidant activities. We predict that, these could lead to an exponential increase in the field of biomedical applications, with the utilization of green synthesized CuNPs, due to its remarkable properties. The highest antibacterial property was observed with gram-negative strains mainly, E. coli, due to its thin peptidoglycan layer and electrostatic interactions between the bacterial cell wall and CuNPs surfaces. Hence, CuNPs can be potent therapeutic agents in several biomedical applications, which are yet to be explored in the near future.
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•To prepare the copper nanoparticles using novel medicinal plant Cissus arnotiana•Characterization of CuNPs by different microscopic techniques•To evaluate the antioxidant and antibacterial activity
Propolis samples used for the present study were collected in Transylvania. Our study had the purpose to investigate the amount of total polyphenols and the correlation that it may exist between the ...mentioned class of compounds and antioxidant properties. Polyphenolic profile was determined using Folin-Ciocalteu colorimetric method, while antioxidant activity was investigated by means of free radical scavenging activity (DPPH assay) and ferric reducing antioxidant power (FRAP assay). The content in polyphenols for analyzed propolis samples ranged between 24.46 and 62.39 g standard mixture/ 100 g propolis. All propolis samples showed antioxidant activity. The correlation between polyphenolic profile of propolis and its antioxidant properties was found to be positive.
•Physiology and metabolite contents of roselle plants were investigated upon GA3, IAA, and chitosan nano-fiber (CNF) treatments.•The SEM images show the internalization/localization of CNF inside the ...calyxes.•A synergistic effect was observed following application of two plant growth regulators.•CNF further influenced the plant growth regulators effects on most of the traits evaluated.•Combined application of IAA, GA3 and CNF could be employed for enhancement of plant height, number of calyxes, total chlorophyll, β-carotene, flavonoids and antioxidant activity.
The roselle (Hibiscus sabdariffa L., Malvaceae) is one of the most widely used medicinal plants due to its economic importance and high bioactive compounds. In the present study, the effects of two exogenous plant growth regulators (PGRs), gibberellic acid (GA3) and Indole-3-scetic acid (IAA) at 400, 800 and 1200 mg L−1, along with chitosan-based nanofiber (CNF, at 50, 100 and 200 mg L−1) were investigated, individually and in combination, on plant height, calyx fresh and dry weights, number of flowers, total chlorophyll and ß-carotene, soluble sugar, anthocyanin, vitamin C, total polyphenols and flavonoids as well as antioxidant capacity in roselle plants. According to the results, a synergistic effect was observed between employed PGRs. Of interest, CNF was observed inside the calyxes using scanning electron microscopy (SEM) technique. Because of its unique physio-chemical properties, CNF further influenced the PGRs function on most of the traits evaluated. It was found that the combined use of IAA and GA3 could improve plant height, number of calyxes per plant, total chlorophyll, β-carotene, flavonoids and antioxidant activity in roselle. Furthermore, the results clearly demonstrated that PGRs in combination with CNF have a significant impact on various growth parameters in roselle plant. The present results suggest that the use of combined IAA+GA3+CNF (at 800 + 800 + 100 mg L−1) stimulate both growth parameters and health-promoting phytochemicals content in roselle plants.
Palmyrah fruit pulp which is seasonal, exhibits cleansing and skin moisturizing effects. It also contains carotenoids, which are antioxidants that can nourish and protect the skin from damages caused ...by free radicals induced by factors such as exposure to UV light. Carotenoids from the Palmyra fruit pulp were extracted in the virgin coconut oil and were used to formulate facial cream, soap, and liquid soap. The aim of this study was to determine the antioxidant activity of these three cosmetic products made using the pigment oil extract by the DPPH radical scavenging activity assay. Similar cosmetic products were made using coconut oil (no pigment) as the control samples and a popular commercial cream and soap were used for comparison. The UV-Vis characterization of the pigment oil extract confirmed the presence of β-carotenoids and it has shown green fluorescence under UV light (365 nm). The cosmetic products made using the Palmyra fruit pulp extract showed significantly greater antioxidant activity compared to that of the control and the commercial products. One (1) ml of 1 mg/ml of pigment cream, pigment soap and pigment liquid soap showed 41.58% ( ± 2.40), 66.37% ( ± 2.70) and 60.52% ( ± 0.09) inhibition respectively. The findings of this study suggest that these natural products containing the Palmyra fruit pulp extract have greater antioxidant activity and clinical trials should be done to explore their effects on the human skin.
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•Carotenoids from the Palmyra fruit pulp were extracted and used to formulate cosmetic products like facial cream, soap, and liquid soap.•Antioxidant activity of these cosmetic products was determined by the DPPH radical scavenging activity assay.•The cosmetic products made using the Palmyra fruit pulp extract showed greater antioxidant activity compared to that of the control and the commercial products.
In this study, clove essential oil (CL) or eugenol (EU) containing cellulose acetate (CA) or acrylic component/hydrophobically modified starch (AC/S) coatings on corona treated oriented polypropylene ...film (OPP) were designed and investigated for their possible applications as antioxidant packaging materials for fresh meat. The antioxidant properties of the coatings were investigated by Vapour Phase-DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The CA coatings containing CL or EU showed 43–92% and 43–94% inhibition against DPPH free radicals through the vapour phase, respectively, whereas AC/S/CL and AC/S/EU coatings resulted in DPPH inhibition of 21–65% and 25–84%, respectively. AC/S/EU and CA/EU coatings on OPP containing from 0.32 ± 0.03 to 6.40 ± 0.14 g/m2 of EU were used to prepare packaging for fresh beef (Longissimus thoracis). After 14 days, the lipid oxidation in beef steaks kept in control and antioxidant packages was 3.33 and 1.00–1.22 mg of malondialdehyde per kilogram of meat, respectively. Moreover, red colour of beef in antioxidant packages was retained.
•Coatings containing clove essential oil and eugenol on polypropylene film were designed.•The antioxidant properties of coatings were investigated through the vapour phase.•Eugenol inhibited lipid oxidation in fresh beef and increased its display life.
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