Diphenyl-1-picryl-hydrazyl-hydrate Research Articles

Camellia sinensis Assisted Synthesis of Copper Oxide Nanoparticles (CuONPs) and Assessment of Its Antioxidant Activity and Zebrafish Embryonic Toxicology Evaluation.

- Camellia sinensis,or oolong tea, is a partially fermented version of tea used in Asian countries. The remarkable reduction activity of the tea extract can potentially be used for synthesizing nanoparticles. Recently,Camellia sinensishas gained popularity for the formulation of some metal nanoparticles. Aim To formulate green synthesis of copper oxide nanoparticles (CuONPs) mediated byCamellia sinensis(oolong tea) and assess its cytotoxicity and antioxidant properties. Materials & Methods Oolong tea extract is prepared and added to CuSO4 solution to synthesize CuO nanoparticles (CuONPs). The centrifugation pellet of CuONPs is collected and subjected to DPPH (2,2 - diphenyl -1- picrylhydrazyl hydrate)and H2O2 assays. The cytotoxicity screening is performed using zebrafish embryos. Results The reducing activity of oolong tea successfully synthesizes the copper nanoparticles. High values are obtained in DPPH (63% inhibition at 10µL concentration, 73% inhibition at 20µL, 80% at 30µL, 85% at 40µL and 90% at 50µL concentrations) and H2O2 (50% inhibition at 10µL concentration, 65% at 20µL, 68% at 30µL, 75% at 40µL and 80% at 50µL concentrations) assays. There are no morphological deformities in the zebrafish and no loss of cell viability or delayed hatching at low concentrations (below 4-8 µL), as shown by the viable embryos with no morphological deformities. Conclusion The study has evidenced high antioxidant activity and minimal cytotoxicity of CuO nanoparticles produced usingCamellia sinensis, thus proving it to be a good biomaterial for a wide range of biological applications.

Synthesis and characterization of innovative resveratrol nanobelt-like particles and assessment of their bioactivity, antioxidative and antibacterial properties.

Recently, many studies have shown various beneficial effects of polyphenol resveratrol (Res) on human health. The most important of these effects include cardioprotective, neuroprotective, anti-cancer, anti-inflammatory, osteoinductive, and anti-microbial effects. Resveratrol has cis and trans isoforms, with the trans isoform being more stable and biologically active. Despite the results of in vitro experiments, resveratrol has limited potential for application in vivo due to its poor water solubility, sensitivity to oxygen, light, and heat, rapid metabolism, and therefore low bioavailability. The possible solution to overcome these limitations could be the synthesis of resveratrol in nanoparticle form. Accordingly, in this study, we have developed a simple, green solvent/non-solvent physicochemical method to synthesize stable, uniform, carrier-free resveratrol nanobelt-like particles (ResNPs) for applications in tissue engineering. UV-visible spectroscopy (UV-Vis) was used to identify the trans isoform of ResNPs which remained stable for at least 63days. The additional qualitative analysis was performed by Fourier transform infrared spectroscopy (FTIR), while X-ray diffraction (XRD) determined the monoclinic structure of resveratrol with a significant difference in the intensity of diffraction peaks between commercial and nano-belt form. The morphology of ResNPs was evaluated by optical microscopy and field-emission scanning electron microscope (FE-SEM) that revealed a uniform nanobelt-like structure with an individual thickness of less than 1μm. Bioactivity was confirmed using Artemia salina in vivo toxicity assay, while 2,2-diphenyl-1-picrylhydrazylhydrate (DPPH) reduction assay showed the good antioxidative potential of concentrations of 100μg/ml and lower. Microdilution assay on several reference strains and clinical isolates showed promising antibacterial potential on Staphylococci, with minimal inhibitory concentration (MIC) being 800μg/ml. Bioactive glass-based scaffolds were coated with ResNPs and characterized to confirm coating potential. All of the above make these particles a promising bioactive, easy-to-handle component in various biomaterial formulations.

Antioxidant Activity of Andrographolide from Andrographis paniculataleaf and Its Extraction Optimization by using Accelerated Solvent Extraction

Andrographis paniculata is widely used as a medicinal plant in many countries and andrographolide is the major bioactive compound extracted from A. paniculata leaf. This study purposely to optimize statistical andrographolide extraction using the accelerated solvent extraction (ASE) technique. The Box Behnken design (BBD) was chosen to determine the optimum ASE conditions for the extraction temperature (ºC), cycle number, and extraction time (min) to achieve the highest yield of andrographolide. The optimum ASE conditions were identified as: extraction temperature of 60 ºC, using 3 cycles and 5 min extraction time, with maximum conversion yield as high as 335.2 ± 0.2 mg/g determined by High Performance Liquid Chromatography (HPLC) with the squared correlation coefficients (R2) of 0.97. The findings revealed the ASE method significantly enhanced andrographolide extraction and agreed closely with the predicted value at 337.5 mg/g. Andrographolide was isolated by preparative HPLC technique. A. paniculata leaf extract and extracted andrographolide displayed moderate radical scavenging activity in 2, 2−Diphenyl−1−picrylhydrazyl hydrate (DPPH) assay with IC50 of 0.883 ± 1.597 mg/ml and 0.514 ± 0.285 mg/ml respectively as IC50 for ascorbic acid was 0.048 ± 0.004 mg/ml. A. paniculata extract and andrographolide inhibited the tyrosinase enzyme with IC50 of 0.749 ± 0.293 μg/ml and IC50 of 2.441 ± 2.026 μg/ml indicated stronger tyrosinase inhibition abilities than kojic acid, IC50 of 19.985 ± 0.557 μg/ml. These results suggest that A. paniculata leaf extract and andrographolide have greater potential as sources of biochemical compounds that can be used as skin depigmentation solutions.

Haematological and biochemical changes in arsenic trioxide-induced toxicity in Wistar rats treated with methanol extract of Parquetina nigrescens leaf.

This study was designed to investigate the phytochemical composition and protective effects of methanol extract of Parquetina nigrescens leaf (MEPL) in male Wistar rats. Phytochemical screening, in vitro antioxidant assay, gas chromatography-mass spectrometry (GC-MS) and LD50 were determined. Forty male Wistar rats were grouped into eight and orally treated for 54 days as follows: Group 1 (10% tween 80), Group 2 (3 mg/kg As2O3) Groups 3, 4 and 5 (250, 500 and 1000 mg/kg MEPL) and groups 6, 7 and 8, (250 mg/kg+As2O3, 500 mg/kg+As2O3 and 1000 mg/kg+As2O3). The animals were sacrificed on day 55 under anaesthesia. Blood was collected by cardiac puncture for heamatological studies. Liver concentrations of malondialdehyde (MDA), superoxide dismutase (SOD), aspartate aminotransferase (AST), alanine amino transferase (ALT) and alkaline phosphatase (ALP) activities were determined spectrophotometrically. Liver histology was also assessed. Flavonoids, tannin, alkaloids, saponin, and anthraquinone were present in MEPL, also, MEPL scavenged 2,2 diphenyl-1-picrylhydrazyl hydrate (DPPH) and Azino-bis-3-ethylbenzthiazoline-6-sulphonic acid radical (ABTS+). The IC50 of MEPL required to chelate metal was also low. The GC-MS revealed the presence of 24 essential oil. The LD50 was > 5000 mg/kg. Packed cell volume and red blood cell count were significantly reduced in 1000 mg/kg MEPL group, white blood cell count and SOD activity reduced (P<0.05) in 3 mg/kg As2O3 when compared with control but increased in groups co-treated with As2O3 and 250, 500 or 1000 mg/kg + As2O3. MDA concentration, AST, ALT and ALP activities increased significantly in 3 mg/kg As2O3 group but decreased (P<0.05) in groups co-treated with As2O3 and 250, 500 or 1000 mg/kg. The methanol extract of Parquetina nigrescens leaf in male Wistar rats has antioxidant, hepatoprotective and white blood cell protective effects.

Phytochemicals and Antidiabetic, Antioxidant and Anti-inflammatory Activities of Ethanol Flower Extract of Syzygium aromaticum (L.) Merr. &amp; Perry (Myrtaceae)

Syzygium aromaticum (L.) Merr. &amp; Perry is a spice that has been used traditionally for centuries to preserve food and treat for a number of ailments. This research was carried out to analyze phytochemicals and to determine antidiabetic, antioxidant and anti-inflammatory activities of 95 % ethanol flower extract from S. aromaticum (FESA). The GC-MS analysis demonstrated the presence of 17 bioactive compounds in FESA, with eugenol (56.17 %) the most active compound. Antidiabetic activity study revealed that the inhibitory activity of the FESA against α-glucosidase enzyme was stronger than the activity of Acarbose, an antidiabetic drug. In addition, the FESA exhibited potent antioxidant activity by inhibiting 2, 2- diphenyl-1-picrylhydrazylhydrate (DPPH) free radicals higher than butylated hydroxyltoluene (BHT), a synthetic antioxidant. Furthermore, the FESA potentially inhibited the nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 cells but less effective than Diclofenac, a non-steroidal anti-inflammatory drug. The activities of FESA are partly due to the presence of active compounds. The results obtained confirm the antidiabetic, antioxidant and anti-inflammatory properties, and the traditional used of S. aromaticum for the treatment of diabetes and oxidative and inflammatory-related diseases. HIGHLIGHTS The most predominant bioactive compound in FESA is eugenol (56.17 %), analyzed by GC-MS FESA inhibits α-glucosidase activity significantly higher than acarbose, an antidiabetic drug. The FESA is therefore helpful to delay or possibly prevent the development of the diabetic complication The FESA exhibits DPPH radical scavenging activity is more potent than BHT, an antioxidant compound The FESA can provide a novel natural anti- inflammatory agent resource, as evidenced by the inhibitory effect of FESA on nitric oxide (NO) production GRAPHICAL ABSTRACT

A novel green preparation of zinc oxide nanoparticles with Hibiscus sabdariffa L.: photocatalytic performance, evaluation of antioxidant and antibacterial activity

ABSTRACT This study investigates the eco-friendly synthesis of zinc oxide nanoparticles (ZnO NPs) utilizing an aqueous solution of Hibiscus sabdariffa L. flower extract, which is acts as reducing agent as well as capping agent. The Fourier transform infrared spectroscopy (FTIR) results revealed the presence of flavonoids and phenols in the plant extract, indicating that they were the major agents capable of reducing zinc nitrate salt. According to our x-ray diffraction (XRD) results, ZnO-NPs exhibit a particular phase wurtzite structure. The ZnO-NPs are spherical in shape and have an average size of 15 nm, according to the measurements of electron microscope (SEM) and transmission electron microscope (TEM) measurements. Energy dispersion (EDX) analysis demonstrates that the NPs are mainly composed of zinc and oxygen. The zeta potential of these nanoparticles shows that they are very stable. The antibacterial activity of ZnO-NPs was tested using agar dilutions with a variety of gram-positive and gram-negative microorganisms. According to the research results, ZnO-NPs can be established as an extremely specific antibacterial agent for a wide variety of organisms to prevent bacterial growth. Furthermore, the antioxidant properties of ZnO-NPs were determined using the 2,2 diphenyl-1-picrylhydrazyl hydrate (DPPH) radical scavenging approach, and the IC50 value of 38 μg/mL was measured for ZnO-NPs. Furthermore, the biosynthesized ZnO-NPs showed significant catalytic performance of methyl orange (MO) under UV irradiation. Overall, ZnO-NPs in their produced state have excellent potential in biomedical and wastewater treatment applications. Radical scavengers were used to evaluate the role of radicals in the reaction mechanism.

Multi dye degradation, antibacterial, antidiabetic and antioxidant assessment of silver nanoparticles (Ag-NPs) derived via leaves of Smilax aspera

Biosynthesized nanomaterials are in high demand due to their potential in medical applications and the search for efficient biosynthesized nanomaterials continues. The endeavor of this research work is to synthesize silver nanoparticles (Ag-NPs) utilizing an aqueous extract of Smilax aspera (S. aspera) leaves. Several analytical techniques were used to investigate the shape, morphology and size of NPs. UV–visible spectroscopy exhibited a band at 472 nm indicating the formation of Ag-NPs, phytoconstituents functioning as capping or reducing agent are revealed by FT-IR, XRD (X-Ray diffraction) verified cubic crystalline structure having (h,k,l) values at (1 1 1), (2 0 0), (2 2 0), (3 1 1) and (2 2 2). Energy dispersive X-rays spectroscopy confirmed the purity of elemental silver, Scanning electron microscopy as well as Transmission electron microscopy (TEM) reported that particles are in a spherical shape with a normal particle size of 34 nm. Furthermore, in DLS data two peaks at 5.89 nm (5%) and 39.99 nm (95%) were observed, which supports the TEM finding. The Synthesized Ag-NPs have shown significant antibacterial activity against pathogens due to the capping of the bioactive components of Smilax aspera leaves. Furthermore, The antioxidant potential of synthesized Ag-NPs was calculated performing 2,2 diphenyl-1-picrylhydrazyl hydrate (DPPH) free radical scavenging assay. Moreover, Methylene blue, Rose bengal, and Acridine orange dyes have also been degraded employing Ag-NPs as a catalyst. Inhibition of carbohydrate hydrolyzing enzymes, in addition to the previously mentioned actions, emphasized the antidiabetic efficacy of these produced Ag-NPs. Overall, Ag-NP’s efficient bioactivities indicate their promising future in biomedical and environmental remediation applications.

Changes in Content of Bioactive Compounds and Antioxidant Activity Induced in Needles of Different Half-Sib Families of Norway Spruce (Picea abies (L.) H. Karst) by Seed Treatment with Cold Plasma.

In order to ensure sufficient food resources for a constantly growing human population, new technologies (e.g., cold plasma technologies) are being developed for increasing the germination and seedling growth without negative effects on the environment. Pinaceae species are considered a natural source of antioxidant compounds and are valued for their pharmaceutical and nutraceutical properties. In this study, the seeds of seven different Norway spruce half-sib families were processed for one or two minutes with cold plasma (CP) using dielectric barrier discharge (DBD) plasma equipment. At the end of the second vegetation season, the total flavonoid content (TFC), DPPH (2,2- diphenyl-1-picryl-hydrazyl-hydrate), and ABTS (2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) antioxidant activity, and the amounts of six organic acids (folic, malic, citric, oxalic, succinic, and ascorbic) were determined in the needles of different half-sib families of Norway spruce seedlings. The results show that the TFC, antioxidant activity, and amounts of organic acids in the seedling needles depended on both the treatment duration and the genetic family. The strongest positive effect on the TFC was determined in the seedlings of the 477, 599, and 541 half-sib families after seed treatment with CP for 1 min (CP1). The TFC in these families increased from 118.06 mg g−1 to 312.6 mg g−1 compared to the control. Moreover, seed treatment with CP1 resulted in the strongest increase in the antioxidant activity of the needles of the 541 half-sib family seedlings; the antioxidant activity, determined by DPPH and ABTS tests, increased by 30 and 23%, respectively, compared to the control. The obtained results indicate that the CP effect on the amount of organic acids in the needles was dependent on the half-sib family. It was determined that treatment with CP1 increased the amount of five organic acids in the needles of the 541 half-sib family seedlings. The presented results show future possibilities for using cold plasma seed treatment in the food and pharmacy industries.

Anti-inflammatory and cytotoxic effect of lycopene and raspberry in-situ gel.

Preparation of an in-situ gel containing lycopene and raspberry plant formulation and analysis of its anti-inflammatory and antioxidant effects is described. Lycopene is known for its anticancer and antioxidant activity. It induces apoptosis, thereby reducing the cancer cells, and also reduces the injury of cells due to oxidative activity. Similarly, raspberry also contains antioxidants properties which can help to reduce oxidative stress and chronic inflammation. This study includes extracts containing 25% of Raspberry and 10% lycopene, carboxymethyl cellulose, hydroxypropyl methyl cellulose, Carbopol, sodium chloride, and distilled water. This in-situ gel was then tested for antioxidant and anti-inflammatory assay using DPPH (2, diphenyl 1-picryl- hydrazyl- hydrate) and bovine serum albumin (BSA), antioxidant assay revealed that the inhibition percentage was more with 50 µL (61.3) of gel and anti-inflammatory assay showed significant results with 10 µL (90.2) of gel. In-situ gel containing lycopene and Raspberry has significant anti-inflammatory and antioxidant activity.

Cultivar Differences on Nutraceuticals of Grape Juices and Seeds

In this study, nutraceutical properties of fruit juice and seeds, which are important for human health, of green (Kabarcik, Cavus), red (red Globe) and black (Honusu, Yildiz, Yediveren and Helvani) skin colored grape cultivars grown in same ecological conditions were investigated. Harvest period, number of seeds, cluster form, cluster weight, berry weight, berry color and usage area were determined as morphological parameters. The Folin-Ciocalteu method was used for total phenol content analysis. The total antioxidant status of juices and seeds of grape cultivars have been determined by 2,2–diphenyl−1–picryl-hydrazyl–hydrate (DPPH), ferric reducing antioxidant power (FRAP) and trolox equivalent antioxidant capacity (TEAC) assays. Seeds of all grape cultivars exhibited higher nutraceuticals than fruit juices. Total phenolic content of seed samples was found to be quite variable in range of 1.90 mg GAE/g (cv. Yildiz)–3.46 mg GAE/g (cv. Honusu) fresh weight base (FW), indicating 2 folds of differences between green and black grape cultivars. Green and black cultivars also showed the lowest and the highest total phenolic content in juices between 1.69 (cv. Yediveren) and 2.45 (cv. Honusu mg GAE/g FW). Seeds and fruit juices of all cultivars analyzed showed high antioxidant capacity and total phenol content. Of all different colored cultivars, black peel-colored cultivars had the highest values and combined better morphological and nutraceutical traits with an excellent berry qualitative profile for cv. Honusu and Helvani.

Antibacterial, antioxidant and photodegradation potential of ZnO nanoparticles mediated via roots of Taraxacum officinale radix

Nanomaterials are in high demand due to their potential in biomedical applications. This research work accounts to synthesize ZnO nanoparticles (ZnO-NPs) utilizing the green method using an extract of roots of Taraxacum officinale radix. To investigate the nanoparticles various techniques viz; UV–Vis spectrophotometer, FTIR, Energy dispersive X-Ray spectroscopy (EDX), Transmission electron microscopy (TEM), (XRD) X-ray diffraction, Zeta potential analyzer were used. An absorption peak value at 365 nm in the UV–Vis spectrum suggested the formation of ZnO NPs. FTIR identifies phytoconstituents that act as a capping or reducing agent. The XRD analysis confirmed that ZnO-NPs are hexagonal crystalline in nature, with miller indices (h, k, l) of (1,0,0), (0,0,2), (1,0,1), (1,0,2), (1,0,3), (2,0,0), (2,0,1), (2,0,0), (2,0,1). (1,0,4). Additionally, morphological examinations using TEM and SEM revealed that the integrated particles were spherical (23.35 nm), and EDX analysis proves that the NPs are predominantly composed of Zinc and Oxygen (88.2%,3 keV). The zeta potential indicates that these nanoparticles are quite stable. ZnO-NPs were evaluated for their antibacterial activity against Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Streptococcus pneumoniae respectively. According to the findings, ZnO-NPs could be developed as an antibacterial agent that is highly specific for a broad range of microorganisms in order to prevent bacterial contamination. Additionally, these ZnO -NPs acted as a catalyst in the degradation of the dyes methylene blue, rose bengal, and acridine orange. Further, the antioxidant activity of ZnO-NPs was estimated utilizing the 2,2 diphenyl-1-picrylhydrazyl hydrate (DPPH) radical scavenging method and the IC50 value of 127.75 µg/ ml was calculated for ZnO-NPs. In general, ZnO-NPs in their produced state promise a bright future in biomedical and wastewater treatment applications.

The antibacterial and antioxidant efficacy and neutron sensing potency of 10B enriched hexagonal boron nitride nanoparticles

Current work reports the excellent antibacterial and antioxidant activities of the hexagonal boron nitride nanoparticles (10BNNPs) synthesized with enriched-Boron (10B) in a horizontal dual-zone quartz tube furnace. The antibacterial activities of the as-synthesized 10BNNPs are tested by using the well-diffusion technique. According to the antibacterial results, it has been found that 10BN-NPs are highly responsive to K. pneumoniae and least responsive to P. aeruginosa bacterial strains. The antioxidant activity of 10BNNPs is analyzed by scavenging free radicals of 2,2–diphenyl–1–picrylhydrazyl hydrate (DPPH) with time interval and variation in concentration of 10BN-NPs. The activity of DPPH scavenging of 10BNNPs is observed by UV and visible light Spectrophotometer. The results show that the antioxidant potential of 10BNNPs is up to 79.5%. In addition, the 10B-contents with a semiconductor nature, the synthesized 10BNNPs offer a great potential to be used in Boron neutron capture therapy (BNCT) for tumor cells destruction and as a sensing element in a solid-state neutron detector.

Hesperetin loaded proposomal gel for topical antioxidant activity

The present study was aimed at formulating and evaluating hesperetin-loaded proposomal gel for topical antioxidant activity. Hesperetin-loaded proposomes were first formulated and optimized with the central composite design and were characterized for particle size, polydispersity index, zeta potential and entrapment efficiency. In vitro release studies were also performed for the formulation. Various polymeric gel bases were assessed and one of them was selected to formulate the proposomal gel. The gels were characterized for their appearance, content uniformity, viscosity, spreadability and swelling index. In vitro diffusion studies were also carried out on the proposomal gel. Finally, in vitro antioxidant potentials of hesperetin and the proposomal formulation was determined using the 2,2- diphenyl-1-picrylhydrazyl hydrate (DPPH) assay. The optimized proposomal formulation showed enhanced in vitro drug release with a release of 95.51 ± 8.85% after 84 h compared to the hesperetin dispersion which released only 34.00 ± 1.71%. 1% carbopol was selected as a suitable gel base for the proposomal gel. The proposomal gel formulated showed good properties and was able to further sustain the drug release from the proposomes by releasing 42.63 ± 2.11% of the drug after 144 h. Finally, hesperetin and hesperetin-loaded proposomes showed comparable in vitro antioxidant activities with IC50 values of 82.15 μg/mL and 88.07 μg/mL, respectively. We can conclude that hesperetin-loaded proposomal gel can be an effective formulation with a controlled release profile and could be used to treat topical oxidative conditions.

In-vitro evaluation of antioxidant and anticholinesterase activities of novel pyridine, quinoxaline and s-triazine derivatives

Cholinesterase enzymes such as acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) cause hydrolysis of acetylcholine (ACh), a neurotransmitter responsible for the cognitive functions of the brain such as acquiring knowledge and comprehension. Therefore, inhibition of these enzymes is an effective process to curb the progressive and fatal neurological Alzheimer's disease (AD). Herein, we explored the potential inhibitory activities of various pyridine, quinoxaline, and triazine derivatives (3a-k, 6a-j and 11a-h) against AChE and BuChE enzymes by following the modified Ellman's method. Further, anti-oxidant property of these libraries was monitored using DPPH (2,2′-diphenyl-1-picryl-hydrazylhydrate) radical scavenging analysis. From the studies, we identified that compounds 6e, 6f, 11b and 11f behaved as selective AChE inhibitors with IC50 values ranging from 7.23 to 10.35 μM. Further studies revealed good anti-oxidant activity by these compounds with IC50 values in the range of 14.80–27.22 μM. The kinetic studies of the active analogues demonstrated mixed-type of inhibition due to their interaction with both the catalytic active sites (CAS) and peripheral anionic sites (PAS) of the AChE. Additionally, molecular simulation in association with fluorescence and circular dichroism (CD) spectroscopic analyses explained strong affinities of inhibitors to bind with AChE enzyme at the physiological pH of 7.2. Binding constant values of 5.4 × 104, 4.3 × 104, 3.2 × 104 and 4.9 × 104 M−1 corresponding to free energy changes −5.593, −6.799, −6.605 and −8.104 KcalM−1 were obtained at 25 °C from fluorescence emission spectroscopic studies of 6e, 6f, 11b and 11f, respectively. Besides, CD spectroscopy deliberately explained the secondary structure of AChE partly unfolded upon binding with these dynamic molecules. Excellent in vitro profiles of distinct quinoxaline and triazine compounds highlighted them as the potential leads compared to pyridine derivatives, suggesting a path towards developing preventive or therapeutic targets to treat the Alzheimer's disease.

GC-MS Based Identification of the Volatile Components of Six Astragalus Species from Uzbekistan and Their Biological Activity.

The compositions of volatile components in the aerial parts of six Astragalus species, namely A. campylotrichus (Aca), A. chiwensis (Ach), A. lehmannianus (Ale), A. macronyx (Ama), A. mucidus (Amu) and A. sieversianus (Asi), were investigated using gas chromatograph-mass spectrometry (GC-MS) analysis. Ninety-seven metabolites were identified, accounting for 73.28, 87.03, 74.38, 87.93, 85.83, and 91.39% of Aca, Ach, Ale, Ama, Amu and Asi whole oils, respectively. Sylvestrene was the most predominant component in Asi, Amu and Ama, with highest concentration in Asi (64.64%). In addition, (E)-2-hexenal was present in a high percentage in both Ale and Ach (9.97 and 10.1%, respectively). GC-MS based metabolites were subjected to principal component analysis (PCA) and hierarchal cluster analysis (HCA) to explore the correlations between the six species. The PCA score plot displayed clear differentiation of all Astragalus species and a high correlation between the Amu and Ama species. The antioxidant activity was evaluated in vitro using various assays, phosphomolybdenum (PM), 2,2 diphenyl-1-picryl-hydrazyl-hydrate (DPPH), 2,2-azino bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), cupric reducing antioxidant capacity (CUPRAC), ferric reducing power (FRAP) and ferrous ion chelation (FIC) assays. In addition, the potential for the volatile samples to inhibit both acetyl/butyrylcholinesterases (AChE, BChE), α- amylase, α-glucosidase and tyrosinase was assessed. Most of the species showed considerable antioxidant potential in the performed assays. In the DPPH assay, Ama exhibited the maximum activity (24.12 ± 2.24 mg TE/g sample), and the volatiles from Amu exhibited the highest activity (91.54 mgTE/g oil) in the ABTS radical scavenging assay. The effect was more evident in both CUPRAC and FRAP assays, where both Ale and Ama showed the strongest activity in comparison with the other tested species (84.06, 80.28 mgTE/g oil for CUPRAC and 49.47, 49.02 mgTE/g oil for FRAP, respectively). Asi demonstrated the strongest AChE (4.55 mg GALAE/g oil) and BChE (3.61 mg GALAE/g oil) inhibitory effect. Furthermore, the best tyrosinase inhibitory potential was observed for Ale (138.42 mg KAE/g). Accordingly, Astragalus species can be utilized as promising natural sources for many medicinally important components that could be tested as drug candidates for treating illnesses such as Alzheimer’s disease, diabetes mellitus and oxidative stress-related diseases.

EFFECT OF PRESERVATION METHODS ON THE BIOACTIVE COMPOUNDS OF THYMUS VULGARIS

Thyme (T. is used mainly as a food seasoning, as a source of essential oils with applications in the food sector, but also as a worming and bactericidal agent in medicine . In this study, it was investigated the effect of different preservation methods on the quantitative and qualitative parameters of the bioactive compounds from T. vulgaris The antioxidant properties and total phenols were examined using the stable 2,2 diphenyl 1 picrylhydrazyl hydrate (DPPH) free radical scavenging method and Folin Ci ocalteu method during the storage process.The samples were subjected to screening for their possible antibacterial activities against some human pathogenic bacteria. Results demonstrated that thyme methanol extract possessed the highest antioxidant activi ty, when the plants were dried at room temperature in dark conditions. This storage method could be advisable either for medicinal or food industry usage. The study concluded that the optimal preserving method for thyme is drying at room temperature in lac k of light. After a 5 months storage period, the investigated bioactive compounds were found in high concentrations.

Evaluation of phytochemical properties and larvicidal activities of Cynodon dactylon, Clerodendrum viscosum, Spilanthes acmella and Terminalia chebula against Aedes aegypti

Objective: To investigate the phytochemical, antioxidant and larvicidal property of Cynodon dactylon, Clerodendrum viscosum, Spilanthes acmella and Terminalia chebula against Aedes aegypti. Methods: Antioxidant capacity of methanolic extract of the plants was studied by 2,2- Diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assay, ferric reducing antioxidant power assay, 2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonate) assay (ABTS), thiobarbituric acid reactive substance (TBARS) assay, superoxide anion scavenging activity and total antioxidant activity assay following standard protocol. Total phenolic content, total flavonoid content, carbohydrate, and plant protein were also estimated following standard protocols. Larvicidal property of plant extracts were determined following World Health Organization standard protocol. Additionally, glutathione-s-transferase (GST) and acetylcholinesterase (AchE) inhibitory property was also tested biochemically. Results: Phytochemically, high protein, carbohydrate and phenolic were found in Terminalia chebula, while Cynodon dactylon showed high flavonoid contents. Similarly, high antioxidant activity was found in Terminalia chebula with IC50 values at 13.7, 2.9, 45.2 and 46.0 μg/mL in DPPH, ABTS, TBARS and superoxide anion scavenging activity, respectively. Larvicidal study showed strongest activity in Spilanthes acmella followed by Cynodon dactylon, and Clerodendrum viscosum and Terminalia chebula. GST and AchE of Aedes aegypti larvae showed reduced enzyme activity when pre-incubated with Cynadon dactylon and Spilanthes acmella. Conclusions: The methanolic crude extracts of Cynodon dactylon, Clerodendrum viscosum, Spilanthes acmella and Terminalia chebula possess strong antioxidant and larvicidal property against Aedes aegypti and therefore, may be further investigated for the molecular mode of action.

Study of in vitro and in vivo free radical scavenging activity for radioprotection of cerium oxide nanoparticles

Nanoceria have shown numerous unique characteristics, such as biocompatibility and are excellent agents for biological applications. The aim of this study is to investigate cerium oxide nanoparticles for 2, 2- diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical scavenging activity and their ability to offer protection against ionizing radiation. In vitro antioxidant activity study of nanoceria particles has shown good free radical scavenging activity for DPPH radical assayed within a concentration range of 0.01 to 0.05 g/l, at higher concentrations of nanoparticles showed reverse trend in absorbance and inhibition indicating this finite rang of concentration is suitable for scavenging free radicals, also nanoparticles were found to have significant antioxidant capacity and thus can be used as potential radical scavenger against deleterious damages caused by the free radicals. The results of histopathological examination showed effectiveness of CeO2 nanoparticles in radioprotection of skin cells in animal models during radiation exposure.

Synthesis and characterization of zinc oxide nanoparticles using tuber extract of anchote (Coccinia abyssinica (Lam.) Cong.) for antimicrobial and antioxidant activity assessment

Coccinia abyssinica (C. abyssinica) tuber extract assisted biosynthesized Zinc oxide nanoparticles (ZnO Nps) were characterized using UV-visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Blue shift of absorptional peak to 365 nm indicated formation of ZnO Nps. X-ray diffraction showed well defined peak characteristic of the Nps. FESEM and TEM image revealed the synthesized nanoparticles has a hexagonal shape and the average particle size was 10.4 nm. The antimicrobial activities of the synthesized ZnO Nps were tested using well diffusion assay and Staphylococcus aureus (MTCC-3160) was found to be the most sensitive against synthesized ZnO Nps whereas, least sensitivity was exhibited by Salmonella typhimurium (MTCC-1251).Free radical scavenging capacity of ZnO Nps were assessed using 2,2–diphenyl-1-picrylhydrazylhydrate (DPPH) assay, with varying ZnO Nps concentration, which showed scavenging activity with IC50 = 127.74 μg /mL.

Synthesis, characterization and evaluation of antioxidant properties of catechin hydrate nanoparticles

Catechin hydrate (CH), is an important phyto compound, reported to have potential therapeutic activity for prevention and treatment of various central nervous system (CNS) disorders. However, its therapeutic action is limited by their low oral bioavailability, poor stability and intestinal absorption, therefore, development of a targeted nanoparticle based carrier system which can overcome its physicochemical limitations and can enhance its biological activity is required. The objective of the present study was to formulate nanoparticle based formulation by ionic gelation method for catechin hydrate. After optimizing the formulation by statistical tool, further, characterization results showed zeta average particle size of 68.76 ± 1.72 nm along with polydispersibility index of 0.174 ± 0.081 and zeta potential of −5.32 mV. Moreover, TEM analysis also confirmed its nanometric size range (range of 61.8–128 nm) and FT – IR scan showed no bond formation between polymers and loaded extract (CH). The in vitro compound release kinetics showed a typical linear diffusion profile and cytotoxicity analysis done on NB41A3 cell lines results exhibited the cell viability of 89.5 ± 0.25% in catechin loaded nanoparticles (CH NPs) whereas, it is 82.7 ± 0.34% in CH indicating negligible toxicity in nanoparticle based formulation. The stability testing was done for CH NPs after 8 weeks, and results revealed minimal degradation of catechin. Lastly, the antioxidant activities estimated through DPPH (2, 2–Diphenyl-1-picrylhydrazyl-hydrate), Nitric oxide (NO) and Hydrogen peroxide (H2O2) scavenging assays revealed that CH NPs have higher and prolonged anti-oxidant activity in comparison with CH.