Papaya (Carica papaya L. cv. Hongkong) is an economically important fruit crop grown in Malaysia. During its ripening stages, (C. papaya L.) exhibits different physicochemical properties, antioxidant capacities, and sensory quality results. The objective of this study was to elucidate in detail the antioxidant capacity of C. papaya as determined by total phenol content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP),2,2-diphenyl-1-picrylhydrazyl (DPPH) and scavenging systemand (ABTS). The study also aimed to study physicochemical changes of papaya fruits based on measured pH, titratable acidity (TA), total soluble solids (TSS), moisture and fruit color at five different stages of ripening. The fruits were harvested at five different, stages RS1, RS2, RS3, RS4, and RS5 corresponding to 12, 14, 16, 18, and 20 weeks after anthesis, respectively. Significant differences were found at different stages of ripening. The pH of the fruit decreased significantly (P < 0.05), whereas TA, moisture, and TSS increased significantly (P < 0.05) during the ripening process. The redness (a*) and yellowness (b*) values of fruit color both increased significantly (P < 0.05), whereas
lightness (L*) varied. The total phenol content TPC, TFC, FRAP, DPPH and ABTS values increased significantly (P < 0.05) with the ripening process. Sensory evaluation based on the color, sweetness, sourness, flavor, and overall acceptance for the last three maturity stages was also performed. RS5 had a better score than RS3 or RS4. The results showed the important role of the ripening stage in increasing the antioxidant content of papaya fruits.
This study aimed to compare the antioxidant content and antioxidant capacity of pulp and peel of two varieties of pomelo fruit (Tambun White and Tambun Pink). Antioxidants including total phenolic content, total flavonoid content and ascorbic acid content were determined using Folin-Ciocalteu reagent assay, aluminium chloride colorimetric assay and AOAC method, respectively. Antioxidant capacity of pomelo pulp and peel was measured using ferric reducing antioxidant potential and trolox equivalent antioxidant capacity assays. The peels of both pomelo fruits had higher antioxidant content and capacity than their pulps. Moreover, the white variety of pomelo had higher antioxidant content and capacity compared to the pink counterpart. Trolox equivalent antioxidant capacity of the samples was positively high correlated with total phenolic content (r = 0.978) and total flavonoid content (r = 0.959), except for ascorbic acid. Therefore, pomelo peel from white variety possessed higher antioxidant properties and it is potentially rich sources of natural antioxidants.
Consumption of mushroom has increased remarkably because of their desirable aroma, taste and high nutritional content. This study was undertaken to measure and compare the antioxidant activity, total phenolic content (TPC) and total flavonoid content (TFC) of Agaricus bisporous (white button mushroom) and Agaricus brasiliensis (Brazilian mushroom) in aqueous and 60% ethanol extract. Results showed that button mushroom (21.47 ± 0.48 mg GAE/g of dry weight) had significant higher TPC in aqueous whereas Brazilian mushroom (12.50 ± 0.22 mg GAE/g of dry weight) had significant higher TPC in 60% ethanol (p< 0.05). In terms of TFC, Brazilian mushroom had higher content than button mushroom in both types of solvents. For FRAP assay, Brazilian mushroom had significantly higher total antioxidant activity than the button mushroom in 60% ethanol (p < 0.05) but opposite trend with aqueous. For DPPH radical scavenging activity, Brazilian mushroom (60% ethanol) had the lowest EC50 value, followed by button mushroom (60% ethanol), Brazilian mushroom (aqueous) and button mushroom (aqueous). Pearson correlation test (p < 0.05) showed strong positive correlation between TPC and FRAP assay in both extracts (r = 0.969 for 60% ethanol extract; r = 0.973 for aqueous extract). For TFC, there was a strong positive, correlation with FRAP assay (r = 0.985) in aqueous extract. In conclusion, high antioxidant activity in ethanol extract of mushrooms due to presence of phenolic content can potentially be used as a source of natural antioxidants.
In this study, two types of plants materials were used namely Garcinia atrovirdis and Cynometra
cauliflora to determine the proximate composition, mineral content and antioxidant activities. Total phenolic content (TPC) and ferric reducing antioxidant power (FRAP) assay had been used to determine antioxidant activity in both samples. The moisture, ash, fiber, fat, protein and carbohydrate content in both samples were determined by using Association of Official Analytical Chemists (AOAC) methods. Mineral content in the sample was determined using Atomic absorption spectrophotpmetry (AAS). The results showed higher TPC and FRAP values in Cynometra cauliflora compared to Garcinia atrovirdis. Methanol extractions gave higher TPC and FRAP values compared to water extraction. The results obtained indicated that both samples have the potential to be as a source of natural antioxidants. Further study should be conducted to explore the benefits of underutilized fruits not only in antioxidant activity but other usages as well.
Antioxidant capacity of Ocimum tenuiflorum L. or ‘ruku’ were determined in this study. Fresh
leaves of Ocimum tenuiflorum was subjected to freeze drying, vacuum drying and processed
into fermented and unfermented tea. The samples were extracted using distilled water and the
total phenolics, total flavonoids, condensed tannin content, anthocyanins and total antioxidant
capacity (TAC) were assessed, measured with ferric reducing antioxidant power (FRAP)
and 1,1-diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH) assays. The results
showed that drying the fresh leaves of Ocimum tenuiflorum and processing them into tea leaves
significantly increase (P < 0.05) the antioxidant capacity, total phenolic content, total flavonoid
content, and condensed tannin content. However, anthocyanins content showed reduction
after drying. In the present study, it can be concluded that the vacuum drying method seem
to produce a product with higher quality of antioxidant properties than freeze drying. Hence,
vacuum drying can be used to replace freeze drying as it is also cheaper than freeze drying.
The plant extract serves not only as a good source of bioactive compounds but also as natural pigment that can be applied as colourants in food and pharmaceutical products. The aim of this study were to determine the anthocyanin content of Garcinia mangostana peel extract (GMPE), Clitoria ternatea extract (CTE) and Syzigium cumini extract (SCE) in relation to their antioxidant activity and their colour properties. The antioxidant activities related to the phenolic constituents including anthocyanin content were determined based on the EC50 of DPPH radical scavenging activity and Ferric Reducing Antioxidant Power (FRAP) assay. The colour properties of the plant extracts were measured based on their degradation index (DI), indices of polymeric colour (PC) and colour density (CD). GMPE showed higher FRAP value and lower EC50 value which were 79.37 mmoles/g and 0.11 mg/ml, respectively, as compared to SCE extract with FRAP value, 25.66 mmoles/g and EC50 value, 0.22 mg/ml. Total monomeric anthocyanin (tmAcy) exhibited a strong correlation between FRAP assay (r2 = 0.998) and DPPH assay (r2 = 0.859). GMPE showed high CD (1.63 AU), moderate PC (0.18 AU) but low in DI (1.19 AU) while SCE exhibited low in CD (0.55 AU) and PC (0.07 AU) but moderate DI (1.26 AU). CTE exhibited high in DI (5.39 AU) and PC (0.19 AU) but moderate in CD (0.55). Hence, it can be concluded that colour pigment obtained from GMPE exhibited high antioxidant activity and better colour properties as compared to SCE and the strong correlation between tmAcy and two antioxidant activity assays which are FRAP and DPPH indicated that monomeric anthocyanin plays a major role in antioxidant activity of these plant extracts.
The effects of sodium chloride (NaCl) (3.5%) solution and polysaccharides, such as carboxymethyl cellulose (CMC) (0.1, 0.3 and 0.5%) and gum arabic (5, 10 and 15%), on the physicochemical properties, antioxidant capacity and sensory characteristics of bitter gourd juice were investigated. An increase in the concentration of CMC and gum arabic significantly was observed to increase the lightness (L value) and the viscosity (mPas) of bitter gourd juice at all levels. Increased concentrations of gum arabic significantly increased the total soluble solids. The bitter gourd fruit treated with NaCl solution produced the highest lightness (L value) and scavenging activity of free radical 2,2-diphenyl-1-picrylhydrazyl of bitter gourd juice. Increased concentration of gum arabic up to 15% significantly increased the total phenolic content. The addition of 5% gum arabic effectively reduced the bitterness of the bitter gourd juice. Viscosity of the juice resulted in negative correlation for bitterness.
The extraction of phenolics from Citrus hystrix leaf was carried out using supercritical fluid extraction and was optimized using response surface methodology (RSM). The effects of CO2 flow rate, extraction pressure and extraction temperature on yield, total phenolic content and diphenyl-picrylhydrazyl-IC50 were evaluated and compared with ethanol extraction. The extraction pressure was the most significant factor affecting the yield, TPC and DPPH-IC50 of the extracts, followed by CO2 flow rate and the extraction temperature. The optimum conditions of pressure, CO2 flow rate and temperature were at 267 bars, 18 g/min and 50°C, respectively. The yield, TPC and DPPH-IC50 obtained were 5.06%, 116.53 mg GAE/g extract and IC50 of 0.063 mg/ml, respectively. These values were not significantly different (p
This study was undertaken to evaluate the antioxidant and acetylcholinesterase inhibition properties of stems and leaves of hexane and methanolic extracts of Pluchea indica. Methanolic extract of leaves showed the highest antioxidant activity (IC50 = 24.45 ± 0.34 µg/ml) and total phenolic contents (573.52 ± 6.2 mg GAE/100 g crude extract), in DPPH radical scavenging and Folin-Ciocalteu assays respectively, however, it failed to inhibit acetylcholinesterase in TLC bioautographic detection. The rest of plant extracts, including methanolic extract of stems, hexane extract of both leaves and stems, were detected to have acetylcholinesterase inhibitory properties. Hexane extract of both leaves and stems exhibited lower or negligible level of antioxidant activity and phenolic contents. Pluchea indica may provide a potential natural source of bioactive compounds, and maybe beneficial to the human health.
The present study was carried out to determine the antioxidant activity and total phenolic content of Ocimum basilicum collected from different regions of the world. The accession V1 is from Sudan, V2 from Iraq, V3 from Germany, V4 from Thailand, V5 from Russia and V6 from Maldives. The extracts from six basil accessions were analysed for their DPPH free radical scavenging activity and their total phenolic content (TPC). The results suggest that the highest antioxidant activity was found in V6 (from Maldives) and the lowest antioxidant activity was found in V4 (from Thailand). The highest amount of phenolic content was found in V6 (from Maldives) and the lowest phenolic content was found inV4 (from Thailand). This study shows that basil is a good source of free-radical scavenging compounds that have their traditional medicinal applications.
The aim of this study was to evaluate the presence and possibility of extracting compounds with antioxidant properties of soybean cake to extend the storage stability of soybean oil. Results showed that the highest DPPH radical scavenging activity was observed for sample to solvent ratio 1:25 while extracting by 70% ethanol for 3 h). The most phenolic compounds equivalents (Gallic acid) was observed for sample to solvent ratio 1:25 while extracting by 70% methanol for 14 h. In addition, the soybean cake extract at concentrations of 50, 100, 150 and 200 ppm in soybean oil could significantly lower the peroxide, diene and p-anisidine values of soy oil during storage at 65 °C.
It is crucial to determine several protein-related parameters at the initial stages of proteomic analysis of any biological samples. In this study, crude protein content, total soluble protein, total phenolic content and the SDS-PAGE profile of fifteen varieties of seaweed from Semporna, Sabah, Malaysia were analysed. The crude protein, total soluble protein and total phenolic content of all seaweed samples were in the range of 3.99 to 13.18 % of dry weight, 0.52 to 1.45 mg/mL in acetone dried powder samples and 8.59 to 48.98 mg PGE/g dry weight, respectively. In general, the differences (crude protein, total soluble protein and total phenolic content) among all fifteen varieties of seaweeds were significant (p< 0.05). There was also a strong positive correlation between crude protein and total soluble protein concentration (Pearson’s Correlation Coefficient (r)=0.923; p=0.01) in these fifteen varieties of seaweed. A distinctive protein pattern was observed in the SDS-PAGE gels between three different seaweed classes of green, red and brown colours. All of these results are important in sample preparations (extractions) before furthering proteomic analysis in order to identify and characterize seaweed proteomes.
In this work, potato slices were exposed to different doses of UV-C irradiation (i.e. 2.28, 6.84, 11.41, and 13.68 kJ m(-2)) with or without pretreatment [i.e. ascorbic acid and calcium chloride (AACCl) dip] and stored at 4 ± 1 °C. Changes in enzymatic activities of polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonia lyase (PAL), as well as total phenolic content (TPC) were investigated after 0, 3, 7 and 10 days of storage. Results showed that untreated and UV-C treated potato slices at 13.68 kJ m(-2) dosage level showed significantly higher PPO, POD and PAL activities. Conversely, untreated potato slices showed the lowest TPC during storage period. Potato slices subjected to AACCl dip plus UV-C at 6.84 kJ m(-2) produced lower PPO, POD and PAL activities, as well as maintained a high TPC during storage.
Leaves from three varieties of Ficus deltoidea, colloquially termed small- (FDS), medium- (FDM), and big-type leaf (FDB), were subjected to water extraction. The crude extracts were fractionated using water (WF) and ethyl acetate (EAF). The phenolic and flavonoid content, antioxidant activity, and cytotoxicity of the fractions were investigated. The EAF had the highest phenolic and flavonoid content compared to the other FDS fractions. Conversely, the FDM crude extract had the highest phenolic and flavonoid content compared to the other FDM samples. Antioxidant activity was highest in the FDB crude extract. Ultra-high-performance liquid chromatography showed that two compounds, vitexin and coumaric acid, were present in the FDB crude extract. Additionally, the F. deltoidea leaves caused no signs of toxicity in a normal liver cell line. Our findings show that F. deltoidea varieties have excellent antioxidant activity with no cytotoxic effects on normal liver cells.
This review paper briefly explains the meaning and characteristics of endocrine disrupting compounds (EDCs). EDCs comprise various types of natural and synthetic chemical compounds that can impede the reproductive action of the endocrine system in animals and humans. Further discussion is on bisphenol A (BPA), one of the examples of EDCs that is extensively used in industries nowadays. It acts as a monomer, which is desired in the production of polycarbonate plastics and epoxy resins. BPA later ends up in environmental compartments (air, water, sediment). In spite of this, BPA is not categorized as a persistent compound and it will be degraded either by photolysis or bacteria. It can only exist between three and five days in the environment. The concentration of BPA varies in different locations depending on the temperature, pH, source and time of sampling. BPA has been frequently debated due to its toxicity and carcinogenicity towards animals and humans. This paper also explains several extraction procedures and analytical methods concerning how to identify BPA in either aqueous or solid samples. However, an additional review is needed in respect of how to handle, reduce the level of BPA in the environment and understand the details concerning the existence of BPA.
Environmental pollution is one of the major concerns in the 21st century; where billions of tonnes
of harmful chemicals are produced by industries such as petroleum, paints, food, rubber, and
plastic. Phenol and its derivatives infiltrate the ecosystems and have become one of the top major
pollutants worldwide. This review covers the major aspects of immobilization of phenoldegrading
bacteria as a method to improve phenol bioremediation. The use of various forms of
immobilization matrices is discussed along with the advantages and disadvantages of each of the
immobilization matrices especially when environmental usage is warranted. To be used as a
bioremediation tool, the immobilized system must not only be effective, but the matrices must be
non-toxic, non-polluting and if possible non-biodegradable. The mechanical, biological and
chemical stability of the system is paramount for long-term activity as well as price is an
important factor when the very large scale is a concern. The system must also be able to tolerate
high concentration of other toxicants especially heavy metals that form as co-contaminants, and
most immobilized systems are geared towards this last aspect as immobilization provides
protection from other contaminants.
Phenol Formaldehyde (PF) resin has been extensively used in the manufacturing industry as a binding agent, especially in the production of wood-based panels because of its ability to provide good moisture resistance, exterior strength and durability as well as excellent temperature stability. However, due to the use of limited petroleum-based phenol in its formulation, there is a strong interest in exploring renewable biomass material to partially substitute the petroleum-based phenol. In this study, the slow pyrolysis of biomass decomposition process was used to convert two types of biomass, namely, oil palm frond and Rhizophora hardwood, into bio-oil. The phenol-rich fraction of the bio-oil was separated and added into the formulation of PF resin to produce an environmentally-friendly type of PF resin, known as bio-oilphenol-formaldehyde (BPF) resin. This BPF resin was observed to have comparable viscosity, better alkalinity, improved non-volatile content and faster curing temperature than conventional PF resin. Moreover, the particleboard bonded with this BPF resin was observed to have just as excellent bonding strength as the one bonded using conventional PF resin. However, the BPF resin exhibited an increased level of free formaldehyde and less thermal stability than the conventional PF resin, probably due to the addition of the less reactive bio-oil.
The aim of the study was to develop response surface methodology (RSM) models for polymer loading, density, dimensional stability, strength and stiffness of compressed wood of sesenduk (Endospermum diadenum) treated with phenol formaldehyde (PF). Central composite design (CCD) using RSM with three processing parameters was studied in their specific ranges: PF concentration (PC) from 24-40%, pre-curing time (PCT), 3-9 h and compression ratio (CR), 70-90%. The experimental design was analysed and interpreted using the Design Expert Software (Stat Ease version 8) and the responses of 3d plots were built using the same software. Quadratic models in terms of PC, PCT and CR were developed for polymer loading, density, reduction in water absorption and modulus of rupture in static bending. Multiple linear equations were developed for anti-swelling efficiency and modulus of elasticity. The experimental values were in good agreement with predicted ones and the models were highly significant with correlation coefficients between 0.626 and 0.926. PC and CR had significant effects on the responses. The range of PCT used did not significantly affect the responses. It was also found that the improvement of properties ranged from moderately to highly correlated with the polymer loading in the compreg wood.
The effect of solvent type in antioxidant compounds extraction from banana tissues was studied. The solvent system used was pure methanol, ethanol, acetone and their aqueous solution at 50% and 70% concentrations. Comparison among three common cultivars of banana in Malaysia (Berangan, Mas and Raja) had been done and their antioxidant activities were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging system, ferric reducing ability in plasma (FRAP)
assays and total phenolic content (TPC) assays. Acetone 70% had the strongest antioxidant compounds extraction power as compared to other solvent. All banana samples were found to be low in primary antioxidant but powerful secondary antioxidant source of fruit. The ascending order of banana cultivars in term of their antioxidant activities in all antioxidant assays carried out were Berangan < Mas < Raja. FRAP-TPC assays were highly correlated (R2>0.70) than FRAP-DPPH
and TPC-DPPH assays due to the same mechanism that occurred in the reaction of FRAP and TPC assays.
Ganoderma lucidum has been recognized as a precious fungus in both Chinese and Japanese traditional medicine for
centuries. It contains many bioactive ingredients such as triterpenoids and polysaccharides. The present study used
supercritical carbon dioxide (SC-CO2
) fractionation to fractionate Ganoderma lucidum extract into four fractions (R,
F1, F2, & F3) and evaluate the correlation between the content of functional components and their antioxidant ability.
Relatively high concentrations of the three types of bioactive constituents were simultaneously partitioned into different
fractionation collecting vessels. The free radical scavenging ability was greatest in F1. The IC50 of DPPH scavenging ability
was 0.90 mg/mL and that of ABTS radicals scavenging activity was 0.45 mg/mL. The correlation analysis of antioxidant
ability with total triterpenoids and total polyphenols showed a positive relationship. In conclusion, this study showed
that fractionation of Ganoderma lucidum extract using SC-CO2 fractionation technology was able to effectively partition
its bioactive components including triterpenoids, polysaccharides and phenolic compounds and also to increase the
antioxidant activities of the fractions.