Terms Of Antioxidant Activity Research Articles

Antibacterial activity of ethyl acetate extract of endophytic fungus (Paraconiothyrium brasiliense) through targeting dihydropteroate synthase (DHPS)

Endophytic fungi are innumerable sources of bioactive metabolites with various biomedical applications. Hence, this study was aimed to isolate and identify the endophytic fungus Paraconiothyrium brasiliense (PB) from the fruit of Capsicum annuum and evaluated their biochemical, antimicrobial, antioxidant, cell viability, and cytotoxicity behavior. Results showed that ethyl acetate extract (EAE) of PB contains flavonoid (31.53 ± 0.9 mg of QE/g of extract) and phenolic (2.59 ± 0.06 mg of GAE/g of extract). The PB-EAE showed significant antioxidant activity in terms of free radicals (DPPH, ABTS, and Fe3+) scavenging. The antioxidant potential of PB-EAE reflects in normal cell viability and anticancer activity against prostate cancer (PC3) cells. The bacterial inhibitory activity of PB-EAE was equal to commercial antibiotic tetracycline hydrochloride (TCH). Further, GC–MS analysis confirmed the presence of volatile molecules such as o-cymene (CH3C6H4CH(CH3)2), dipentene (C10H16), γ-terpinene (C10H16), 4-carvomenthenol (C10H18O), heneicosane (CH3(CH2)19CH3), and 2,5-piperazinedione (C4H6N2O2). Also, molecular docking analysis demonstrated the significant interactions between the compounds of PB-EAE with dihydropteroate synthase (Protein ID:5JQ9; DHPS). This study revealed that endophytic P. brasiliense could be a novel source for isolation of antimicrobials.

Phytochemical screening and antioxidant and antimicrobial activities of crude extracts of different filamentous fungi.

Five filamentous fungal strains that grew in different whey-based media under submerged fermentation were investigated for antioxidant properties and phytochemicals. Phytochemical analysis revealed the presence of alkaloids, tannin, flavonoids, glycosides, phenols, saponins, and terpenes in the crude intra- and extracellular ethyl acetate extracts of different strains. All fungal extracts exhibited effective antioxidant activities in terms of TPC, TFC, DPPH, FRAP, ABTS, reducing power, and metal chelating capacity. The activities of intracellular extracts were higher than the extracellular metabolites. Fermentation media with sugar and salt supplementation significantly influenced antioxidant production. Aspergillus niger in glucose-supplemented whey medium was found to exhibit the highest antioxidant properties. The antimicrobial activity of A. niger and Penicillium expansum extracts by microtiter plate assay showed a promising result against some pathogenic bacterial strains. Chromatographic analysis of the fungal extracts revealed the presence of chlorogenic acid, trans-cinnamic acid, ferulic acid quercetin, myricetin, kaempferol, and catechin which are known for their antioxidant properties. Accumulation of nutrients in fungal biomass under constraint environment produces secondary metabolites which has demonstrated efficacy towards alleviation of several degenerative diseases. The antioxidative enriched phytochemicals present in these five different fungal strains will provide a breakthrough in the utilisation of whey as inexpensive source of substrate for the growth of these fungi. Moreover, phytochemicals could be utilized as therapeutic agents in a cost-effective and environmentally friendly manner.

K-carrageenan edible films for beef: Honey and bee pollen phenolic compounds improve their antioxidant capacity

The physical, antioxidant, and antibacterial properties of edible k-carrageenan films containing bee pollen and honey extracts, as well as their evaluation in vitro and on beef, are reported for the first time. Thickness, tensile strength, elongation at break, puncture force, contact angle, water vapor permeability, UV-screening, thermal analysis, color, antioxidant activity in terms of iron reducing power (FRAP) and antiradical power on DPPH radical, as well as antibacterial activity against Escherichia coli, Staphylococcus aureus, Pseudomonas spp., aerobic plate counts were determined. All the extracts significantly increased the physical properties and the hydrophilicity of the films. The use of bee pollen and ulmo honey extracts did not significantly change the films color, whereas the quillay honey extract turned them reddish. Thermal stability of films were not affected by antioxidant bee extracts addition. The antibacterial activity of the films added with the extracts, evaluated in isolation or on beef, was not significantly modified with the use of any of the extracts on any of the bacteria evaluated. On the contrary, the antioxidant and antiradical activity of isolated edible films and on meat increased with the use of all the extracts.

Phytochemistry and Bioactivity of Nepeta racemosa Lam.

Background and objectives: The genus Nepeta is used in traditional medicine for the antiseptic and astringent properties in cutaneous eruptions and snake bites. Nepeta racemosa was investigated here due to the rich source of phytochemical compounds in the Nepeta genus and the lack of any phytochemical studies. Methods: The aerial parts were extracted successively using n-hexane, chloroform, and methanol (MeOH) by maceration method, respectively. The MeOH extract was exposed to C18 Sep-Pak fractionation by a step gradient of MeOH-H2O. Further purification of the fractions by preparative reversed-phase HPLC yielded three compounds. The chemical ingredients of essential oil were determined by GC-MS. Free-radical scavenging activity of the extracts, fractions, as well as their total flavonoid and phenolics contents, were assessed using the DPPH method, AlCl3, and Folin-Ciocalteu reagents, respectively. Results: Phytochemical study of 20% and 40% solid phase extraction fractions of MeOH extract yielded one iridoid (8,9-epi-7-deoxy-loganic acid) and two phenylethanoids (forsythoside B and verbascoside), correspondingly. The 4aα,7α,7aα-nepetalactone (31.70 %), germacrene D (7.39 %), n-hexadecanoic acid (6.47 %), were the main compounds of essentials oil. The MeOH extract demonstrated high activity in terms of antioxidant activity, total phenolics content along with total flavonoids content (0.09 ± 0.01 mg/mL, 1581.80 ± 10.28 mg/100g and 33.01 ± 0.02 mg/100g) as well as 40% SPE fraction (0.01 ± 0.00 mg/mL, 659.20 ± 40.32 mg/100g and 22.5 ± 0.37 mg/100g), respectively. Conclusion: The presence of phenylethanoid derivatives as phenolic compounds appears to be an important antioxidant compound in Nepeta racemosa.

In situ thermal modification of kafirin using infrared radiations and microwaves.

Kafirin is a prolamin protein located in the corneous endosperm of sorghum. The conventional thermal processing of kafirin reduces its solubility, which limits its utilization in the food industry. Therefore, the study was aimed to investigate the effect of in situ thermal modification of kafirin using two different electromagnetic thermal treatments, namely infrared (IR) and microwave (MW) radiation, on the physicochemical, structural, thermal, and antioxidant properties. The results demonstrated that both the thermal modifications improved yield, purity, and solubility of the kafirin with a decrease in hydrophobicity. However, IR-treated samples showed higher solubility (910.67 g kg-1 ) and lower hydrophobicity (387.67). The IR modifications also improved the ratio of α helix/β sheets to a great extent. The alterations in the disulfide content were concomitant with the improvement in the thermal stability of kafirin. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed variations in the band intensities of β- and γ-kafirin, indicating alterations in the kafirin subunits. Morphological examination of kafirin revealed surface withering and agglomeration. Notably, IR treatment improved the antioxidant activity more efficiently (from 32.11% to 74.05%). Although both the IR and MW treatments modified kafirin, the effect seemed to be more pronounced in IR modification. The IR-modified kafirin had better solubility and lesser hydrophobicity than MW-modified kafirin. The physicochemical and structural changes induced by IR treatment improved the biological activity of kafirin, in terms of antioxidant activity. Therefore, it was concluded that the in situ IR modification of kafirin can alter its characteristic properties, improving its potential as a food ingredient. © 2021 Society of Chemical Industry.

Insights of Sea Buckthorn Extract’s Encapsulation by Coacervation Technique

Sea buckthorn (Hippophae rhamnoides L.) represents a valuable source of biologically active compounds such as carotenoids and polyphenols. High amounts of these substances are found in its fruits, bark, and leaves. However, their bioavailability is limited and must be increased in order to benefit from the properties they exert. Therefore, the purpose of this study was to increase the stability and bioavailability of sea buckthorn fruit’s bioactives. The sea buckthorn’s bioactive compounds were extracted with a solvent combination between glacial acetic acid, acetone, and water on one side and water only on the other side. Afterward, the phytochemicals from the extracts were encapsulated using the coacervation technique, followed by freeze-drying in order to obtain stable powders. The powders were characterized in terms of antioxidant activity, total carotenoids, β-carotene, lycopene, total polyphenol, and total flavonoid content, color, structure, and morphology. The phytochemical stability of the powders and their antioxidant activity was assessed during 270 days of storage at 4 °C. Moreover, the bioavailability of phytochemicals was measured during in vitro simulated digestibility. Our findings provide insights to promote carotenoids and polyphenols from sea buckthorn as bioactive ingredients with multiple purposes.

Biosynthesis of Selenium Nanoparticles (via Bacillus subtilis BSN313), and Their Isolation, Characterization, and Bioactivities.

Among the trace elements, selenium (Se) has great demand as a health supplement. Compared to its other forms, selenium nanoparticles have minor toxicity, superior reactivity, and excellent bioavailability. The present study was conducted to produce selenium nanoparticles (SeNPs) via a biosynthetic approach using probiotic Bacillus subtilis BSN313 in an economical and easy manner. The BSN313 exhibited a gradual increase in Se reduction and production of SeNPs up to 5–200 µg/mL of its environmental Se. However, the capability was decreased beyond that concentration. The capacity for extracellular SeNP production was evidenced by the emergence of red color, then confirmed by a microscopic approach. Produced SeNPs were purified, freeze-dried, and subsequently characterized systematically using UV–Vis spectroscopy, FTIR, Zetasizer, SEM–EDS, and TEM techniques. SEM–EDS analysis proved the presence of selenium as the foremost constituent of SeNPs. With an average particle size of 530 nm, SeNPs were shown to have a −26.9 (mV) zeta potential and −2.11 µm cm/Vs electrophoretic mobility in water. SeNPs produced during both the 24 and 48 h incubation periods showed good antioxidant activity in terms of DPPH and ABST scavenging action at a concentration of 150 µg/mL with no significant differences (p > 0.05). Moreover, 200 µg/mL of SeNPs showed antibacterial reactivity against Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 9027, and Pseudomonas aeruginosa ATCC 25923. In the future, this work will be helpful to produce biogenic SeNPs using probiotic Bacillus subtilis BSN313 as biofactories, with the potential for safe use in biomedical and nutritional applications.

Protective effects of Stevia rebaudiana extracts on beta cells in lipotoxic conditions

AimsStevia rebaudiana Bertoni leaf extracts have gained increasing attention for their potential protection against type 2 diabetes. In this study, we have evaluated the possible beneficial effects of Stevia rebaudiana leaf extracts on beta-cells exposed to lipotoxicity and explored some of the possible mechanisms involved.MethodsExtracts, deriving from six different chemotypes (ST1 to ST6), were characterized in terms of steviol glycosides, total phenols, flavonoids, and antioxidant activity. INS-1E beta cells and human pancreatic islets were incubated 24 h with 0.5 mM palmitate with or without varying concentrations of extracts. Beta-cell/islet cell features were analyzed by MTT assay, activated caspase 3/7 measurement, and/or nucleosome quantification. In addition, the proteome of INS-1E cells was assessed by bi-dimensional electrophoresis (2-DE).ResultsThe extracts differed in terms of antioxidant activity and stevioside content. As expected, 24 h exposure to palmitate resulted in a significant decrease of INS-1E cell metabolic activity, which was counteracted by all the Stevia extracts at 200 μg/ml. However, varying stevioside only concentrations were not able to protect palmitate-exposed cells. ST3 extract was also tested with human islets, showing an anti-apoptotic effect. Proteome analysis showed several changes in INS-1E beta-cells exposed to ST3, mainly at the endoplasmic reticulum and mitochondrial levels.ConclusionsStevia rebaudiana leaf extracts have beneficial effects on beta cells exposed to lipotoxicity; this effect does not seem to be mediated by stevioside alone (suggesting a major role of the leaf phytocomplex as a whole) and might be due to actions on the endoplasmic reticulum and the mitochondrion.

Effect of Different Processing Conditions on Bioactive Compounds of Selected Grape Varieties

Bioactive compounds in grapes vary in terms of cultivar and processing conditions. Raw juice and treated grape juices from locally grown Israel blue and locally available, imported, Red Globe and Michele Palieri varieties in Sri Lanka were used for the analysis. Grape juices were subjected to different processing conditions such as pasteurization and pectinase enzyme treatment. Total Monomeric Anthocyanin content (TAC), Total Phenolic Content (TPC), and antioxidant activity were analyzed. Compared to the imported grape varieties, the locally grown, pectinase enzyme-treated Israel blue grape juice with 2% pectinase enzyme concentration, 40 0C incubation temperature, and 2 hours incubation time, under dark condition had the significantly highest values (p < 0.05) for TAC at 177.03±4.15 mg/L of malvidin-3-O-glucoside (M3G), TPC at 527.07 ± 3.55 mg/L of Gallic acid equivalents and antioxidant activity in terms of DPPH radical scavenging assay with IC50 value at 7.05±0.35 mg/mL Gallic acid equivalents and ABTS radical scavenging assay with IC50 value at 0.31±0.01 mg/mL of Trolox equivalents. TAC, TPC, and antioxidant activity of three grape varieties showed the highest values in pectinase enzyme-treated grape juice which was followed by raw juice and the pasteurized juice respectively. This research has taken an approach to enhance the bioactivity of grape juices via pectinase enzyme treatment and evaluate the suitability of locally grown Israel blue grape variety in Sri Lanka to form as a functional beverage to meet nutritional and health requirements.

Unraveling the Modulation of Controlled Salinity Stress on Morphometric Traits, Mineral Profile, and Bioactive Metabolome Equilibrium in Hydroponic Basil

Salinity is a major concern in several ecosystems and has a significant impact on global agriculture. To increase the sustainability of horticultural food systems, better management and usage of saline water and soils need to be supported by knowledge of the crop-specific responses to tolerable levels of salinity. The aim of this work was to study the effects of mild salinity on morphological growth and development, leaf color, mineral composition, antioxidant activities, and phenolic profile of sweet basil (Ocimum basilicum L.). Plants grew in hydroponics and were exposed to three nutrient solutions (NSs) differing in the NaCl concentration (either 0, 20, or 40 mM). Inhibitory effects on leaf area, fresh yield, and shoot biomass were evident starting from the lowest NaCl concentration, and they became more severe and wide-ranging at 40 mM, also affecting height and root-to-shoot ratio. Salinity increased the nutritional quality in terms of antioxidant activity and polyphenols in leaves, with a reduction in macroelements at 40 mM NaCl. Moreover, the two mild NaCl concentrations specifically modified the concentration of various phenolic acids in leaves. Overall, the use of a slightly saline (20 mM) NS could be tolerated by basil in hydroponics, strongly ameliorating the nutritional profile in the face of relative yield loss. Considering the significantly higher accumulation of bioactive compounds, our work implies that the use of low-salinity water can sustainably increase the nutritional value and the health-promoting features of basil leaves.

Physiochemical properties of encapsulated bitter melon juice using spray drying

Bitter melons have been proven with anti-inflammatory and anti-diabetic activities. However, due to its short shelf life and bitter taste, the consumption of bitter melon is limited in the United States.Among many encapsulation technologies, spray drying is a cost-effective method for encapsulation of bioactive compounds. Polysaccharides and proteins are vastly used as wall materials for encapsulation of bioactive compounds. The encapsulation of bitter melon juice can provide protection over the bioactive compounds in juice, and can mask the unpleasant taste. In the current study, fresh bitter melon juice was obtained from the common variety, Indian bitter melon. The juice was encapsulated using spray drying with 3 formulas of various material composition and core to wall ratios, namely formula 1 (maltodextrin + gum Arabic), formula 2 (gum Arabic + pectin), and formula 3 (pectin + soy protein isolate). The particle size and encapsulation efficiency were compared among the three formulas. The physiochemical properties of fresh juice and reconstituted juice form the encapsulated powders were compared in terms of antioxidant activities, anti-diabetic activity and anti-inflammatory properties. The results indicated that all the reconstituted juices showed lower antioxidant activities, anti-diabetic activity and anti-inflammatory properties compared to the fresh juice. Among the three encapsulated particles, the particles of formula 3 exhibited the highest antioxidant activity and anti-inflammatory property. The particles from formula 2 exhibited the best anti-diabetic activity. The findings will help to develop encapsulation formulas using natural polymers with desired stability, bioaccessibility and health benefits of encapsulated bioactive compounds. Also, the results will provide guidelines for encapsulation of fruit and vegetable juices with health benefits for industrial practices.

Functional and Antioxidant Properties of Plastic Bottle Caps Incorporated with BHA or BHT

In this study, we prepared new antioxidant active plastic bottle caps by incorporating butylated hydroxyanisole (BHA) or butylated hydroxytoluene (BHT) and 2% (w/w) white masterbatch in high-density polyethylene (HDPE). Fourier-transform infrared (FT-IR) spectrometry revealed that the antioxidants and HDPE were uniformly mixed with noncovalent bonding. In addition, the differential scanning calorimetry (DSC) test revealed that the change in melting point and initial extrapolation temperature of the antioxidant active caps was not significant. Sensory evaluation and removal torque tests validated the suitability of the antioxidant active plastic bottle caps in industrial application. The antioxidant activity increased with a greater concentration of BHA and BHT incorporated in both antioxidant active caps (p < 0.05) and with more impact on the BHA cap compared to BHT cap in terms of antioxidant activity. Migration experiments for 10 days at 40 °C and 2 h at 70 °C showed that active antioxidants in the plastic bottle cap were more easily released into fatty foods and milk products that are highly sensitive to oxidation, and the migration of BHA and BHT did not exceed the maximum amount specified in (EC) No 1333/2008 (<200 mg/kg). As such, the antioxidant active plastic bottle caps inhibited oxidation, thereby ensuring higher food quality.

Optimization of antioxidants recovery from wild thyme (Thymus serpyllum L.) by ultrasound-assisted extraction: Multi-response approach

The main goal of this study was to valorize Thymus serpyllum L., the by-product of filter-tea production, for extraction of polyphenols with high antioxidant capacity by ultrasound-assisted extraction (UAE). Herbal dust is formed during the preparation of raw material for tea packaging, it is separated as a fraction which is unusable in the tea industry and distinguished as an industrial waste. In order to optimize the process, three levels, three variables, face-centered central composite experimental design within the response surface methodology (RSM) was applied. Temperature (50, 65 and 80 °C), extraction time (40, 55 and 70 min) and ethanol concentration (45, 60 and 75 %) were used as independent variables. Selected responses were total extraction yield (Y) and total phenols yield (TP), as well as antioxidant activity parameters obtained by DPPH, ABTS and FRAP assays. Results were fitted to a second-order polynomial model and goodness of fit was determined by regression analysis and analysis of variance (ANOVA). Good accordance between experimental and predicted values was achieved, which suggested that obtained models could be used for multi-response optimization in order to maximize yields of target responses and improve antioxidant potential of T. serpyllum liquid extracts. Furthermore, UAE provided advantages comparing to conventional solid-liquid extraction in terms of antioxidant activity and total extraction and total phenols yield. Therefore, it could be concluded that T. serpyllum herbal dust could be used as raw material for production of antioxidant-rich extracts.

Phenolic compounds, essential oil composition, and antioxidant activity of Angelica purpurascens (Avé-Lall.) Gill.

In this study, methanol extracts (MEs) and essential oil (EO) of Angelica purpurascens (Avé-Lall.) Gill obtained from different parts (root, stem, leaf, and seed) were evaluated in terms of antioxidant activity, total phenolics, compositions of phenolic compound, and essential oil with the methods of 2,2-azino-bis(3ethylbenzo-thiazoline-6-sulfonic acid (ABTS•+), 2,2-diphenyl-1-picrylhydrazil (DPPH•) radical scavenging activities, and ferric reducing/antioxidant power (FRAP), the Folin–Ciocalteu, liquid chromatography−tandem mass spectrometry (LC−MS/MS), and gas chromatography-mass spectrometry (GC−MS), respectively. The root extract of A. purpurascens exhibited the highest ABTS•+, DPPH•, and FRAP activities (IC50: 0.05 ± 0.0001 mg/mL, IC50: 0.06 ± 0.002 mg/mL, 821.04 ± 15.96 µM TEAC (Trolox equivalent antioxidant capacity), respectively). Moreover, EO of A. purpurascens root displayed DPPH• scavenging activity (IC50: 2.95 ± 0.084 mg/mL). The root extract had the highest total phenolic content (438.75 ± 16.39 GAE (gallic acid equivalent), µg/mL)). Twenty compounds were identified by LC−MS/MS. The most abundant phenolics were ferulic acid (244.39 ± 15.64 μg/g extract), benzoic acid (138.18 ± 8.84 μg/g extract), oleuropein (78.04 ± 4.99 μg/g extract), and rutin (31.21 ± 2.00 μg/g extract) in seed, stem, root, and leaf extracts, respectively. According to the GC−MS analysis, the major components were determined as α-bisabolol (22.93%), cubebol (14.39%), α-pinene (11.63%), and α-limonene (9.41%) among 29 compounds. Consequently, the MEs and EO of A. purpurascens can be used as a natural antioxidant source.

Caffeine content and antioxidant activity of various brews of specialty grade coffee [pdf

BACKGROUND The aim of the study was to evaluate the caffeine level and antioxidant activity of brews of specialty grade coffee compared to popular coffee brands. METHODS Ten types of coffee were used, including 7 specialty Arabica, 1 Robusta and 2 popular cheap coffee brands. For caffeine determination, HPLC analysis and the spectrophotometric method were used as reference. The total polyphenol content and antioxidant capacity (DPPH and FRAP methods) were evaluated. For two selected high-quality coffees, the influence of the brewing method on the antioxidant activity and caffeine content in the brews was assayed. RESULTS Regarding the caffeine content, differences between specialty coffee brews and popular products were not found, and an average level amounted to 56 and 40 mg/ml, respectively. In contrast, the antioxidant capacity of specialty coffee brews was significantly higher than for popular ones, independently of the test used. The highest scavenging ability and total phenolic content was found for S3 specialty coffee (46.15% of DPPH inhibition and 58.7 mg GAE/ml, respectively), whereas the lowest was found for popular coffee (about 35% of DPPH inhibition and about 41 mg/GAE/ml). For two selected high-quality coffees, the influence of the brewing method on the antioxidant activity and caffeine content in the brews was tested. It was found that the use of a dripper (overflow brewing method) provides the brew with the best antioxidant properties but with moderate caffeine levels. CONCLUSIONS It was found that 'specialty' quality coffees do not differ from popular brands in terms of caffeine content, but significantly outweigh them in terms of antioxidant activity. This property can be beneficial in the case of a high consumption of coffee, due to antiradical protective effects without the risk of caffeine overdose.

Caffeine content and antioxidant activity of various brews of specialty grade coffee

The aim of the study was to evaluate the caffeine level and antioxidant activity of brews of specialty grade coffee compared to popular coffee brands. Ten types of coffee were used, including 7 specialty Arabica, 1 Robusta and 2 popular cheap coffee brands. For caffeine determination, HPLC analysis and the spectrophotometric method were used as reference. The total polyphenol content and antioxidant capacity (DPPH and FRAP methods) were evaluated. For two selected high-quality coffees, the influence of the brewing method on the antioxidant activity and caffeine content in the brews was assayed. Regarding the caffeine content, differences between specialty coffee brews and popular products were not found, and an average level amounted to 56 and 40 mg/ml, respectively. In contrast, the antioxidant capacity of specialty coffee brews was significantly higher than for popular ones, independently of the test used. The highest scavenging ability and total phenolic content was found for S3 specialty coffee (46.15% of DPPH inhibition and 58.7 mg GAE/ml, respectively), whereas the lowest was found for popular coffee (about 35% of DPPH inhibition and about 41 mg/GAE/ml). For two selected high-quality coffees, the influence of the brewing method on the antioxidant activity and caffeine content in the brews was tested. It was found that the use of a dripper (overflow brewing method) provides the brew with the best antioxidant properties but with moderate caffeine levels. It was found that 'specialty' quality coffees do not differ from popular brands in terms of caffeine content, but significantly outweigh them in terms of antioxidant activity. This property can be beneficial in the case of a high consumption of coffee, due to antiradical protective effects without the risk of caffeine overdose.

Phenolic profiles and antioxidant activities of exocarp, endocarp, and hypanthium of three pear cultivars grown in China

The phenolic composition of the exocarp, hypanthium, and endocarp from three pear cultivars: Jingbai, Korla and Crystal were measured by high-performance liquid chromatography method with diode array detection (HPLC-DAD), while antioxidant activities were investigated using DPPH radical andABTS radical cation scavenging activity, and FRAP. Ferulic acid, chlorogenic acid, and caffeic acid were detected as major components. The exocarp of the Jingbai pear had a relatively high chlorogenic acid content (0.691 mg kg-1) while the hypanthium and endocarp had the high chlorogenic acid content of the three pear varieties. The exocarp of the Korla pear had the highest ferulic acid and rutin content. The exocarp, hypanthium, and endocarp of the Crystal pear had the highest content of chlorogenic acid of the three pear varieties. The Crystal pear presented the highest total phenolic and flavonoid contents and had the highest antioxidant activities in terms of FRAP. The Jingbai pear exocarp presented the highest ABTS value, 83.62 ± 0.08%. The endocarp of the Crystal pear had the highest DPPH value, 87.30 ± 0.03%. Positive correlations were detected among chlorogenic acid, TPC, TFC, and FRAP. The results reveal that the different parts of Pyrus communis L. have effective antioxidant activity for the pharmaceutical application.

Harnessing the potential of UVB irradiation for improving the nutraceutical properties of edible xylotrophic mushroom dried powder

The present study aimed at optimizing the parameters for increasing vitamin D2 content along with other nutraceutical properties (β-glucans, antioxidants, total phenols, flavonoids, and amino acid contents) in dried mushroom Lentinula edodes (L. edodes) powder using ultraviolet B (UVB) irradiation. The dried mushroom powder was irradiated for different time durations (0.5, 1.0, 1.5, 2.0, and 2.5 h). HPLC studies indicated a significant (p < 0.05) increase in vitamin D2 (24.94–49.31 μg/g) content in 2 h irradiated sample. An elevated level of total phenols (6.57–8.84 mg GAE/g), total flavonoids (1.55–2.89 mgQE/g), and β-glucan content (41.20–47.74%) along with improved antioxidant activity (DPPH, FRAP) in the 2 h UVB treated sample was also observed. GCMS profiling revealed the presence of bioactives reported to have medicinal potential. Additionally, the study also targets the alterations made by irradiation in amino acid and color profile. The present study provides a sustainable strategy to improve the nutraceutical potential of dried edible mushroom powder, in terms of antioxidant activities, bioactive constituents, etc., particularly vitamin D2, which holds a significant place in the diet.

Antioxidant, alpha glucosidase and antibacterial evaluation of Syzygium mytifolium (Roxb.) Walp.

Medicinal plants have been the major source of combating and treating infectious diseases and health disorders throughout the ages. To explore new sources of inexpensive and safe antioxidants and antibiotics. The antioxidant and antibacterial potential of different extracts Syzygium mytifolium (Roxb.) Walp. were evaluated through 1,1-Diphenyl-2-Picryl Hydrazyl (DPPH), ferric reducing antioxidant power (FRAP), ?-glucosidase inhibition, disk diffusion and agar well methods. The leaves, bark, root and whole plant of Syzygium mytifolium were extracted with various solvents viz ethanol, methanol and aqueous to give crude extracts, respectively. Among all, the ethanolic extract showed high antioxidant activity in terms of radical scavenging activity, reducing power and alpha-glucosidase inhibition at 1.84 µg/ml, 40.2 mmol/gm and 14.34 µg/ml, respectively. All the tested parts of the plant exhibited moderate to higher range of antibacterial activity against bacterial pathogens with the inhibition zones ranged between 2-27.8 mm. Syzygium mytifolium will serve as a very good source for the development of antioxidant supplements and antibiotics for addressing infectious pathogens and improvement of health status.

Assessment on the Physicochemical and Phytochemical Properties, Nutritional and Heavy Metal Contents, and Antioxidant Activities of Hylocereus polyrhizus Peel from Northern Philippines

Background/Objectives: In the Philippines, Hylocereus polyrhizus is gaining upsurge interest due to its potential health benefits. Aside from the edible fruit pulp, various products from its peel are being developed, and claimed as health boosters. Thus, this study was conducted to assess the physicochemical characteristics, phytochemical constituents, nutritional and heavy metal contents and antioxidant activity of the peel of H. polyrhizus. Methods/Statistical analysis: Physicochemical and phytochemical screening were conducted following established protocols. Nutritional value and trace metals were measured with food analytical standard methods. Antioxidant activity was estimated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing capacity (FRC) assays. Statistical analyses were carried out for DPPH and FRC assays using Graph-Pad Prism. Findings: Results showed that H. polyrhizus peel contains alkaloids, coumarins, flavonoids, phenols, and triterpenoids. Trace amounts of arsenic (0.022 mg/kg), lead (0.887 mg/kg), cadmium (0.068 mg/kg) and chromium (0.225 mg/kg) were detected which were all within the acceptable limit set by the WHO for herbal materials. H. polyrhizus peel contained 6.72% moisture, 14.7% ash, 0.526% total fat, 0.226% saturated fat, 3.73% total sugar, 4.28% crude protein, 73.8% total carbohydrate, and 63.2% total dietary fiber. Other nutrients detected are macronutrients such as K > Ca > Mg > Na, micronutrients Mn > Fe, and Vitamin C. Moreover, it exhibited remarkable antioxidant activity in terms of FRC assay and DPPH assay (IC50 = 986.8mg/mL). The present study results showed that H. polyrhizus peel could be used as a potentially rich source of nutrients and natural antioxidants. Thus, it can be developed as an ingredient for food and health products. Novelty/Applications: The preliminary data obtained provide information that could support the development of products from dragon fruit peel. The conversion of these wastes into utilizable natural health products would help in reducing environmental problems Ma. Danica Ines Ramil et al. / Indian Journal of Science and Technology 2021;14(14):1097–1104 associated with processing waste disposal. Keywords: Antioxidant; Dragon Fruit Peel; Hylocereus polyrhizus; Phytochemical Screening; Nutritional Content; Heavy Metals