Radical Activity Assay Research Articles

Studi Komparasi Aktivitas Antiradikal Bebas Ekstrak Metanol Kulit Buah Pisang Ambon (Musa acuminata Colla) Muda dan Matang dengan Metode DPPH

Ambonese banana fruit peel has antioxidant, antimicrobial, and anti-inflammatory activities. This search aims to investigate the potential of free radical scavengers based on the binding of DPPH free radicals (1,1-Diphenyl-2-picryl Hidrazil). Ambonese banana fruit peel was extracted by maceration using methanol. Free radical activity assay on sample measured by inhibition of DPPH using spectrophotometer UV-Vis at a wavelength at 516 nm. Identification by the TLC method showed that the peel extract of Ambonese banana was active as free radical scavengers where the DPPH solution changed in color from purple to yellow after being sprayed. The calculation results in IC50 values of each sample methanol extract of unripe Ambonese banana fruit peel is 11.78 µg/mL, while the methanol extract of the ripe Ambonese banana fruit peel is 151.56 µg/mL. The standard quercetin has IC50 values of 4.44 µg/mL. The result showed that the methanol extract from the Ambonese banana fruit peel (Musa acuminata Colla) has antioxidantactivity.

Comparative analysis of the volatile constituents of Anvillea garcinii subsp. radiata obtained by Head-Space Solid-Phase Micro Extraction (HS-SPME) and classic hydrodistillation and antioxidant activity of essential oil

ABSTRACT This research aims to extract the essential oil (EO) and a volatile fraction (VF) from Anvillea garcinii subsp. radiata obtained by hydrodistillation (HD) and Head-Space Solid-Phase Micro Extraction (HS-SPME) methods, respectively as well as to examine the antioxidant activity of isolated EO. Gas chromatography (GC) and GC-mass spectroscopy (GC-MS) allowed the identification of 35 and 26 volatile components, representing respectively 90.7% and 91.6% of the total compositions of EO and VF. Quantitative and qualitative differences in two chemoprofiles were observed. Cis 8-acetoxychrysantenyl acetate (30.8%), cis-chrysanthenyl acetate (15.5%) and 6-oxocyclonerolidol (14.9%) were the major constituents of the EO, whereas 6-oxocyclonerolidol (53.9%) and 6-hydroxycyclonerolidol (18.1%) were the main components of HS-SPME extract. The antioxidative activity of the isolated EO was determined by using two different methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical activity assay and the β-carotene bleaching (BCB) test. The results showed that EO expresses satisfactory antioxidant activity with IC50 values of 270.53 and 181.92 μg/ml using DPPH and BCB assays, respectively. To our knowledge, this is the first report describing the VF obtained by HS-SPME-GC-MS method and the antioxidant activity of this species.

Analysis of chemical components and biological activities of essential oils from black and white pepper (Piper nigrum L.) in five provinces of southern China

The chemical composition and antioxidant and antifungal activities of hydro-distilled essential oils (EOs) in black and white Piper nigrum L were evaluated in the present study. Hydro-distilled EOs obtained from black and white P. nigrum L from five areas of China was analyzed by gas chromatography-mass spectrometry (GC-MS). Nineteen compounds were identified, accounting for 98.20–99.35% of the oils. Chemical variation in the oils was estimated using systematic cluster analysis and principal component analysis. Moreover, antioxidant activity was determined by DPPH and ABTS radical cation scavenging assay, ferric reducing power assay, and ferric ion chelating activity assay, scavenging superoxide anion free radical activity assay and antifungal activity were assessed by micro-well dilution assay. Our results suggest that the region of origin greatly influences the pepper's chemical composition and bioactivities, which might support the development and utilization of this promising bio-resource in food industries.

Ferulic Acid, A Component of Angelica Tenuissima Root Extract Induces Anti‐Melanogenic and Anti‐Oxidative Effects

Angelica tenuissima Nakai (Umbelliferae) has been used as a traditional medicine in Asia. The present study investigated the anti‐oxidative and anti‐melanogenic effects of ferulic acid (FA) derived from A. tenuissima root extract (ATE). Anti‐melanogenic activity was determined by intracellular melanin content and tyrosinase activity in α‐MSH (melanin stimulating hormone)‐stimulated B16F10 cells. The anti‐oxidative property of FA was measured using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) scavenging free radical activity assays. FA significantly suppressed the production of melanin and the tyrosinase activity in α‐MSH‐induced cells. FA also showed the significant tyrosinase inhibitory activity and the DPPH/ABTS radical scavenging activities under cell‐free conditions. These results suggest that FA is responsible for the whitening effect of ATE and could be used as an ingredient in cosmeceutical skincare products.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Comparison of chemical compounds associated with sclerites from healthy and diseased sea fan corals (Gorgonia ventalina).

BackgroundThe roles of gorgonian sclerites as structural components and predator deterrents have been widely studied. Yet their role as barriers against microbes has only recently been investigated, and even less is known about the diversity and roles of the chemical compounds associated with sclerites.MethodsHere, we examine the semi-volatile organic compound fraction (SVOCs) associated with sclerites from healthy and diseased Gorgonia ventalina sea fan corals to understand their possible role as a stress response or in defense of infection. We also measured the oxidative potential of compounds from diseased and healthy G. ventalina colonies.ResultsThe results showed that sclerites harbor a great diversity of SVOCs. Overall, 70 compounds were identified, the majority of which are novel with unknown biological roles. The majority of SVOCs identified exhibit multiple immune-related roles including antimicrobial and radical scavenging functions. The free radical activity assays further confirmed the anti-oxidative potential of some these compounds. The anti-oxidative activity was, nonetheless, similar across sclerites regardless of the health condition of the colony, although sclerites from diseased sea fans display slightly higher anti-oxidative activity than the healthy ones.DiscussionSclerites harbor great SVOCs diversity, the majority of which are novel to sea fans or any other corals. Yet the scientific literature consulted showed that the roles of compounds found in sclerites vary from antioxidant to antimicrobial compounds. However, this study fell short in determine the origin of the SVOCs identified, undermining our capacity to determine the biological roles of the SVOCs on sclerites and sea fans.

Essential oil composition and antioxidant activity in Valeriana jatamansi Jones: influence of seasons and growing sources

Valeriana jatamansi is a perennial medicinal herb used in traditional and modern medicines for preventing number of diseases. Root samples were collected from wild and cultivated conditions in different seasons (spring, summer and winter) and analyzed for essential oil composition using gas chromatography – Mass spectrometry (GC–MS). Antioxidant activity of essential oil was evaluated using DPPH (1, 1-Diphenyl-2-picrylhydrazyl radical) assay. A total of thirty compounds (constitutes 80.1–92.1% of total essential oil) were detected by GC–MS analysis. Patchouli alcohol (36.6–52.8%) was recorded as a major compound followed by guaiene epoxide (3.6–11.5%), seychellene (4.2–5.6%), α-guaiene (2.2–4.6%), kessane (2.7–3.6%), α-patchoulene (0.1–2.3%), β-selinene (0.8–3.1 β-acoradienol (0.6–2.4%), ar-curcumene (0.7–2.2%), γ-patchoulene (1.4–2.6%), viridiflorol (0.6–2.4%), and α-humulene (0.1–4.6%). Essential oil content was recorded higher during winter season in wild (0.9%) and cultivated plants (0.8%) as compared to other seasons. Antioxidant activity of essential oil measured by DPPH radical activity assay varied (IC50 = 117.5–227.6 μL/mL) among seasons and growing conditions. Winter season is recommended for maximum essential oil yield and spring season for antioxidant activity.

Effect of acetylation on antioxidant and cytoprotective activity of polysaccharides isolated from pumpkin (Cucurbita pepo, lady godiva)

Acetylation of pumpkin (Cucurbita pepo, lady godiva variety) polysaccharide using acetic anhydride with pyridines as catalyst under different conditions was conducted to obtain different degrees of acetylation on a laboratory scale. Furthermore, antioxidant activities and cytoprotective effects of pumpkin polysaccharide and its acetylated derivatives were investigated employing various established in vitro systems. Results showed that addition of pyridine as catalyst could increase the degree of substitution, whereas volume of acetic anhydride had little effect. The acetylated polysaccharides in DPPH scavenging radical activity assay, superoxide anion radical activity assay and reducing power assay exhibited higher antioxidant activity than that of unmodified polysaccharide. H2O2-induced oxidative damages on rat thymic lymphocyte were also prevented by pumpkin polysaccharide and its acetylated derivatives and the derivatives presented higher protective effects. On the whole, acetylated polysaccharide showed relevant antioxidant activity both in vitro and in a cell system.

Biofunctional Constituents from Liriodendron tulipifera with Antioxidants and Anti-Melanogenic Properties

From the stems of Liriodendron tulipifera, seventeen known compounds have been extracted, isolated and purified. By using spectroscopic analysis, the structures of these pure constituents were determined as three lignans, four steroids and ten benzenoids. Identified compounds were screened for antioxidant abilities using: 1,1-diphenyl-2-picrylhydrazul (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging free radical activity assays; metal chelating power test; and ferric reducing/antioxidant power (FRAP) examination. The result revealed that seventeen compounds had potential anti-oxidative capabilities. In addition, the anti-tyrosinase effect was determined by calculating the hydroxylation of L-tyrosine to L-dopa and the oxidization of L-dopa to dopaquinone, according to in vitro mushroom tyrosinase evaluation platform. Furthermore, based on assays on B16F10 cell line, our data suggest that five compounds isolated from L. tulipifera would be able to inhibit tyrosinase activity and reduce the melanin content in animal cells. Therefore, some of the examined compounds could be potentially used in the cosmetic skin whitening business, therapeutic applications or the food industry.