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Fulltext Optimum Extraction Condition of Clitorea ternatea Flower on Antioxidant Activities, Total Phenolic, Total Flavonoid and Total Anthocyanin Contents

Jaafar NF, Ramli ME, Mohd Salleh R

Trop Life Sci Res, 2020 Jul;31(2):1-17.
PMID: 32922666 DOI: 10.21315/tlsr2020.31.2.1

Clitoria ternatea is a herbaceous plant with many health benefits. Extraction is crucial to obtain its bioactive components which contribute to its antioxidant properties. Therefore, this study was conducted to find an optimum extraction condition of C. ternatea flower on total phenolic content (TPC) and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging activity) as well as to determine its total flavonoid content (TFC) and anthocyanin content based on the optimum extraction condition generated by Response Surface Methodology (RSM)-Design Expert 7.1.5. TPC, TFC and total anthocyanin of C. ternatea were conducted by Folin Ciocalteu (FC), calorimetric assay and pH differential method, respectively. The ranges of selected independent variables were ethanol concentration (30°C-90% v/v), time (60-120 min) and temperature (30°C-70°C). The optimum extraction condition was obtained at 39.62% v/v ethanol concentration, 90 min and 44.24°C. However, these values were slightly adjusted according to the convenience of equipment to operate in which ethanol concentration was adjusted to 37% v/v, time remain at 90 min and temperature at 45°C. The predicted values of TPC and DPPH radical scavenging activity were 41.60 mg GAE/g dry samples and 68.12% inhibition and were experimentally verified to be 41.17 ± 0.5 mg GAE/g dry samples and 63.53 ± 0.95% inhibition of TPC and DPPH radical scavenging activity respectively. This result has showed RSM can optimise TPC and radical scavenging activity of C. ternatea. Upon the optimum condition, the TFC determined was 187.05 ± 3.18 mg quercetin/g dried sample which was higher than TPC and the total anthocyanin content was 28.60 ± 0.04 mg/L. Hence, the extractable phenolic, flavonoid and anthocyanin compounds indicated that C. ternatea is a good source of natural antioxidant.

Matched MeSH terms: Phenols
Anti-Ulcerogenic and Cytoprotective Effects of Saharian (Sidr) Honey from Algeria

Djebli N, Mustafa MR, Keskin M, Kolayli S

Comb Chem High Throughput Screen, 2021;24(10):1664-1670.
PMID: 33208062 DOI: 10.2174/1386207323999201117114008

AIM AND OBJECTIVE: This study aimed at investigating the gastro-protective effects of Algerian Sahara (Sidr) honey from Apis mellifera intermissa against HCl/Ethanol-induced gastric ulcers in rats.
MATERIALS AND METHODS: Total phenolic content, antioxidant activity and phenolic compounds were determined. Then, three groups of rats (control, HCl/ Ethanol-induced ulcer, and orally administered honey) were used for the determination of gastro-protective effect of Sidr honey.
RESULTS: Total phenolic content, total flavonoid content, and DPPH activity of the honey sample were determined as 47.35±3.35 mg GAE/ 100 g, 2.13±0.17 mg QE/ 100 g, and 229.24±0.02 mg/mL, respectively. Oral pretreatment of rats with honey (1.2 g/Kg body weight orally at an interval of 2 days) protected gastric mucosa against HCl/Ethanol-induced damage by decreasing ulcer score, the volume and acidity of gastric juice and increasing pH.
CONCLUSION: These results were confirmed by the histological assessment, which demonstrated a significant gastro-protective activity of Saharian (Sidr) honey against HCl/Ethanol-induced stomach ulcer. Plasma tumor necrosis factor-α, IL-6 and PGE2 were also measured. Sahara honey significantly decreased the plasma TNF-α, PGE2, and IL-6 concentrations.

Matched MeSH terms: Phenols/isolation & purification; Phenols/pharmacology; Phenols/chemistry
Fulltext Ipomea aquatica crude extract inhibits lipoxygenase, hyaluronidase and xanthine oxidase activities

Muhammad Helmi Nadri, Kian, Kai Cheng, Pei, Ying Ong, Hong, Yeng L., Nor Zalina Othman, Nur Fashya Musa, et al.

Journal of Academia Universiti Teknologi MARA Negeri Sembilan, 2020;8(2):9-14.
MyJurnal

Ipomea aquatica, locally known as water spinach, is one of the most common vegetable consumed by
Malaysian. Based on previous studies, crude extract and phenolic compounds of I. aquatica exhibited
several biological activities including antioxidant, anti-microbial and anti-proliferative. The presence
of phenolic compounds in I. aquatica may contributed to their ability to inhibit enzymes, chelate
metals and scavenge free radicals. Currently, no study reported on anti-inflammatory activity of I.
aquatica with respect to lipoxygenase, hyaluronidase and xanthine oxidase enzymes. The present
study aims to enhance current knowledge on biological properties of I. aquatica crude extract
particularly on anti-inflammatory activity. Three enzymes that involve in inflammatory pathway were
selected in this study including lipoxygenase, hyaluronidase and xanthine oxidase. I. aquatica was
extracted in methanol and tested for lipoxygenase, hyaluronidase and xanthine oxidase at different
concentrations using direct enzyme inhibition assay. Lipoxygenase, hyaluronidase and xanthine
oxidase inhibitory activities of the methanol crude extract increased with increasing
concentration. Highest inhibition activity against lipoxygenase, hyaluronidase and xanthine oxidase
were observed at a concentration of 1000 µg/ml with inhibition of 87.18%, 95.36% and 78.38%,
respectively. Our finding in this study indicates potential anti-inflammatory activity of I. aquatica
crude extract through inhibition of lipoxygenase, hyaluronidase and xanthine oxidase.

Matched MeSH terms: Phenols
Surfactant-functionalised magnetic ferum oxide coupled with high performance liquid chromatography for the extraction of phenol

Beh SY, Md Saleh N, Asman S

Anal Methods, 2021 02 07;13(5):607-619.
PMID: 33480366 DOI: 10.1039/d0ay02166k

The usage of phenols in the marketplace has been increasing tremendously, which has raised concerns about their toxicity and potential effect as emerging pollutants. Phenol's structure has closely bonded phenyl and hydroxy groups, thereby making its functional characteristics closely similar to that of alcohol. As a result, phenol is used as a base compound for commercial home-based products. Hence, a simple and efficient procedure is required to determine the low concentration of phenols in environmental water samples. In this research, a method of combining magnetic nanoparticles (MNPs) with surfactant Sylgard 309 was developed to overcome the drawbacks in the classical extraction methods. In addition, this developed method improved the performance of extraction when MNPs and the surfactant Sylgard 309 were used separately, as reported in the previous research. This MNP-Sylgard 309 was synthesised by the coprecipitation method and attracts phenolic compounds in environmental water samples. Response surface methodology was used to study the parameters and responses in order to obtain an optimised condition using MNP-Sylgard 309. The parameters included the effect of pH, extraction time, and concentration of the analyte. Meanwhile, the responses measured were the peak area of the chromatogram and the percentage recovery. From this study, the results of the optimum conditions for extraction using MNP-Sylgard 309 were pH 7, extraction time of 20 min, and analyte concentration of 10.0 μg mL-1. Under the optimized conditions, MNP-Sylgard 309 showed a low limit of detection of 0.665 μg mL-1 and the limit of quantification was about 2.219 μg mL-1. MNP-Sylgard 309 was successfully applied on environmental water samples such as lake and river water. High recovery (76.23%-110.23%) was obtained.

Matched MeSH terms: Phenols
Fulltext Quality attributes of fresh pineapple-mango juice blend during storage

Rosnah Shamsudin, Zulkifli, N. A., ?Amanina Amani Kamarul Zaman?

International Food Research Journal, 2020;27(1):141-149.
MyJurnal

Blending or mixing two or more of fruit juices is able to improve the quality of juices as
compared to single flavour. Pineapple and mango are among the popular tropical fruits in
Malaysia. Despite the massive production of pineapple in Malaysia, utilisation of pineapple as
a juice remains unpopular due to its exotic and strong flavour. Blending of pineapple with
mango is believed to overcome this issue. Nevertheless, suitable blending ratios play important role in the end product quality. The present work aims to determine the physicochemical
and nutritional quality of fresh blended pineapple-mango juice at different blending ratios for
25 days of refrigerated storage (4 ± 2°C). Physicochemical (colour, pH, titratable acidity, and
total soluble solid) and nutritional (vitamin C, total phenolic content, and total antioxidant
content) properties of fresh pineapple-mango juice blends of ratio 80% pineapple with 20%
mango (R80:20) and 50% pineapple with 50% mango (50:50) were determined throughout 25
days of storage. Pineapple-mango juice blends at blending ratio of R80:20 exhibited better
qualities in term of colour (lightness, chroma, hue, and browning index), chemical composition, and nutritional content.

Matched MeSH terms: Phenols
Fulltext Comparison of antioxidant components and antioxidant capacity in different parts of nutmeg (Myristica fragrans)

Tan, K.P., Khoo, H.E., Azrina, A.

International Food Research Journal, 2013;20(3):1049-1052.
MyJurnal

This study aimed to determine and compare antioxidant components and antioxidant capacity in different parts (skin, pulp, mace and seed) of nutmeg. Freeze dried samples were extracted using 80% methanol, while Folin-Ciocalteu assay was employed to determine total phenolic content, aluminium chloride assay was applied to determine total flavonoid content and ascorbic acid was assessed by titrimetric method. Antioxidant activities were evaluated by ferric reducing antioxidant power and trolox equivalent antioxidant capacity (TEAC) assays. Results revealed that nutmeg seed contained the highest TPC followed by mace, skin and pulp. Similar observation was also found for TFC. The highest ascorbic acid content was found in nutmeg mace, while the lowest was in its pulp. For antioxidant activity, nutmeg seed possessed the highest FRAP and TEAC values, while nutmeg pulp had the lowest as compared to other parts. Phenolic compounds in nutmeg samples have exhibited strong correlation with antioxidant capacity. Therefore, nutmeg is a potential functional food with high antioxidants, especially nutmeg seed. Phenolic compounds in nutmeg samples have exhibited strong correlation with antioxidant capacity. Therefore, nutmeg is a potential functional food with high antioxidants, especially nutmeg seed.

Matched MeSH terms: Phenols
Fulltext Effect of different drying methods on phytochemicals and antioxidant properties of unfermented and fermented teas from Sabah Snake Grass (Clinacanthus nutans Lind.) leaves

Lusia Barek, M., Hasmadi, M., Zaleha, A.Z., Mohd Fadzelly, A.B.

International Food Research Journal, 2015;22(2):661-670.
MyJurnal

Clinacanthus nutans (Burm. F.) Lindau or locally known in Sabah, Malaysia as ‘Sabah Snake Grass’ has been ethnobotanically used to treat various diseases in Asian countries. This study was conducted to determine the total phenolics content (TPC), flavonoids content (TFC) and antioxidant activity of herbal teas developed from C. nutans leaves with different drying techniques (microwave-oven dried and freeze dried) and infusion time (1, 2, 5, 10, 15 and 20 min). Ferric reducing/antioxidant power (FRAP) assay, 2,2’-azino-bis(3-ethylbenzothiazoline- 6-sulphonic acid (ABTS) and 2, 2-diphenyl-1-pycryl-hydrazyl (DPPH) free radical scavenging assays were used to investigate the antioxidant capacity. The highest TPC of herbal tea was observed in 20 min infusion of unfermented microwave-oven dried leaves (177.80 ± 19.10 mg TAE/L), while the highest TFC was observed in 10 min infusion of fermented microwave-oven dried leaves (22.13 ± 1.53 mg CE/L). Short infusion times from 5 min to 15 min were able to extract high amount of phenolics compounds. Unfermented tea contained higher TPC content (P < 0.05) as compared to fermented tea, while, TFC showed no significant difference between both types. Freeze dried infusion shows no significant difference (P > 0.05) as compared to microwave-oven dried for TPC, TFC and antioxidant capacity. Moderate and low correlation was observed between TPC and FRAP values (r = 0.507) and between TFC and ABTS values (r = 0.256). Preparation of C. nutans herbal tea as potential natural antioxidant source can be used as a basic reference for future research on the dietary intake of these herbal teas.

Matched MeSH terms: Phenols
Fulltext Effect of blanching on enzyme and antioxidant activities of rambutan (Nephelium lappaceum) peel

Nurhuda, H.H., Maskat, M.Y., Mamot, S., Afiq, J., Aminah, A.

International Food Research Journal, 2013;20(4):1725-1730.
MyJurnal

Rambutan (Nephelium lappaceum) peel is a potential source of antioxidant. As rambutan is a seasonal fruit, a proper heat treatment prior to storage is necessary. Thus, this study was conducted to determine the effect of water and steam blanchings on browning enzymes and antioxidant activities of rambutan peel extracts. Rambutan from the variety of ‘Anak Sekolah’ were peeled and the peel was blanched in boiling water for 0, 2.5, 5 min and by autoclaving for 0, 5, 10 and 15 min. The residual peroxidase (POD) and polyphenoloxidase (PPO) activities, antioxidant activity (2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity), total polyphenol content (TPC) and peel extract colour were determined. The results showed that both water and steam blanchings significantly reduced (p < 0.05) POD and PPO activities. The results also indicated that the increase in the blanching period did not significantly reduce the enzyme activities further. In terms of antioxidant activity, the thermal pretreatment caused no significant difference in the contents of phenolic compounds, as well as the antioxidant capacity of the final product.

Matched MeSH terms: Phenols; Polyphenols
Fulltext Physicochemical quality, antioxidant compounds and activity of MD-2 pineapple fruit at five ripening stages

Ding, P., Syazwani, S.

International Food Research Journal, 2016;23(2):549-555.
MyJurnal

Although Malaysia is one of the important pineapple fruit producing and exporting country, the production of MD-2 pineapple fruit only started in 2009. Pineapple fruit has been harvested at different ripening stages for different markets. The information on Malaysian grown MD-2 pineapple fruit quality is lacking. Therefore this work was carried out with the aim to determine physicochemical quality, antioxidant compounds and activity of MD-2 pineapple fruit at five ripening stages. Ripening stage affected physicochemical quality of MD-2 pineapple fruit. Soluble solids concentration of MD-2 pineapple fruit increased from 15.41 to 18.02% SSC when fruit ripened from stage 1 to 4 and no significant difference was found in fruit between stage 4 and 5. The ascorbic acid content decreased while total carotenoids content increased as ripening stage advanced. The total phenolic content of both 80% methanol and water extraction solvents increased significantly as fruit ripened from stage 1 to 3 and reduced as fruit ripened to stage 5. The antioxidant activity of MD-2 pineapple fruit as assayed using DPPH, FRAP and ABTS showed similar trend as total phenolic content. These results suggest that ripening stage affect MD-2 pineapple fruit quality and nutritional values.

Matched MeSH terms: Phenols
Phenolic water pollutants in a Malaysian River basin

Abdullah P, Nainggolan H

Environ Monit Assess, 1991 Oct;19(1-3):423-31.
PMID: 24233958 DOI: 10.1007/BF00401330

Phenolic chemicals with their very low taste and odour thresholds, high persistence and toxicity, are of growing concern as water pollutants. The compounds are known to exist in raw water as well as in treated water. The level of phenolic priority pollutants in water within the catchment area of the Linggi River Treatment Plant in Negeri Sembilan, Malaysia, which includes the Linggi river basin, was monitored. The 4-aminoantipyrin colourimetric method was used to determine total phenols whereas capillary column gas chromatography was used to determine the individual compounds. The results show that at most sampling stations, particularly those within the Seremban municipality, the level of phenols was found to exceed the recommended Malaysian standard of 2.0 μg/L(-1) for raw water. This is seen as the direct impact of industrial and urbanization of the area and clearly indicates the unhealthy state of the Linggi river. The results also indicate the need to improve the water quality if the river is going to be used as a source of raw water.

Matched MeSH terms: Phenols
Fulltext Quantification of total phenolics in different parts of Pluchea indica (less) ethanolic and water extracts

Normala, H., Suhaimi, M.I.

Pertanika Journal of Science & Technology, 2011;19(1):19-24.
MyJurnal

One of the compounds present in Pluchea indica extracts is antioxidant which plays an important role in inhibiting free radicals and thus protects humans against infections and degenerative diseases, such as cancer, arthritis, and ageing process. The main objective of this study was to investigate and determine the total phenolic compounds of Pluchea indica in different concentrations of ethanolic extracts. This species was chosen because of its high phytonutrient compounds with potential medicinal properties. There was a significant difference (P ≤ 0.05) in the total phenolic among the different parts of the tested plant. 50% of the ethanolic extract produced the highest total phenolic compounds (1775.00±86.00 to 658.95±5.00 µmol/g), followed by water extract (759.79±1.53 µmol/g) and 100% ethanol extract (352.72±22.30 to 249.29±5.37 µmol/g), respectively. In terms of the plant parts, the leaves contained the highest phenolic compounds (1775.00±86.00 µmol/g in 50% ethanol extract, 759.79±1.53 µmol/g in 100% aqueous extract and 352.72±22.30 µmol/g in 100% ethanol extract), followed by the stems (990.22±24.00 µmol/g in 50% ethanol extract, 990.22±24.59 µmol/g in 100% aqueous extract and 293.48±0.00 µmol/g in 100% ethanol extract). Meanwhile, lower total phenolic compounds were detected in the flowers (727.71±11.00 µmol/g in 50% ethanol extract, 603.81±8.46 µmol/g in 100% aqueous extract and 249.29±5.37 µmol/g in 100% ethanol extract) and roots (658.95±5.00 µmol/g in 50% ethanol extract, 450.00±10.76 µmol/g in 100% aqueous extract and 272.28±0.53 µmol/g in 100% ethanol extract). Based on these findings, Pluchea indica has potential medicinal properties that can be further developed to produce neutraceutical products, diet supplements or cosmetic products. However, further research should first be conducted on the effects of these compounds on laboratory animals.

Matched MeSH terms: Phenols
Fulltext Metabolic engineering of functional phytochemicals

Kabir, M.U., Abdulkarim, S.M., Son, R., Azizah, A.H., Saari, N.B.

International Food Research Journal, 2013;20(1):35-41.
MyJurnal

Phytochemicals belonging to the group’s phenols, terpenes, betalains, organosulfides, indoles and protein inhibitors are important components in fruits, vegetables, legumes, whole grains and nuts that have health promoting benefits and a variety of applications in food and pharmaceutical industries. Initially only a few of these important phytochemicals are produced commercially by chemical synthesis. However, recent developments in the field of biotechnology have provided metabolic engineering strategies that use microorganisms as cell factories for high production of these products. This review will discuss the general biosynthetic pathways, metabolic engineering and optimization strategies of functional phytochemicals that have received a lot of attention from investigators.

Matched MeSH terms: Phenols
Fulltext Multivariate statistical analysis of antioxidants in dates (Phoenix dactylifera)

Abbas, F.M.A., Foroogh, B., Liong, M.T., Azhar, M.E.

International Food Research Journal, 2008;15(2):193-200.
MyJurnal

Four types of soft dates (SD), three types of semi-dried dates (SDD) and one type of dried dates (DD) were used in this study. The antioxidant activities were assessed using TEAC method (ABTS assay) and the ferric reducing/antioxidant power method (FRAP assay), while total phenolic content (TPC) and total flavonoid content (TFC) were measured using Folin-Ciocalteau and aluminum chloride colorimetric methods. Multivariate analysis of variance (MANOVA), discriminant analysis (DA) and principal component analysis (PCA) were used to analyze the data. MANOVA showed a strong significant difference between the eight types of dates. DA identified the relative contribution of each parameter in distinguishing the dates. DA also identified two functions responsible for discriminating the dates and showed the difference between different types of dates. The first function distinguished DD from other types of dates, whilst the second function discriminated SD and SDD, affording 100% correct assignation. PCA identified only one component responsible for explaining 98.85% of the total variance in antioxidant data. It is suggested that the TEAC method and the quantitative determination of TPC and TFC was suitable for differentiation of dates and quality control.

Matched MeSH terms: Phenols
Fulltext Impact of Non-Thermal Processing on Antioxidant Activity, Phenolic content, Ascorbic Acid content and Color of Winter Melon Puree

Wan Saidatul, S.W.K., Noriham, A., Zainal, S., Khairusy, S.Z., Nurain, A.

International Food Research Journal, 2013;20(2):633-638.
MyJurnal

In the last decade, non-thermal processing for inactivating microorganisms has been developed in response to the worldwide interest for more fresh and improved quality of food products. Winter melon is a very perishable fruit, hence, processing into puree is a necessity. However application of heat in the production of puree could affect the nutritional values, thus, application of non thermal treatment in combination with preservation method is significant for this fruit. This study was conducted to evaluate the effect of non-thermal processing in combining with preservation method on antioxidant activity, level of key antioxidant groups (total phenolic and ascorbic acid content) and the color of winter melon puree. Total phenolic content (TPC) was measured using Folin-Ciocalteu reagent. Ascorbic acid (AA) was determined using 2,6-dichlorophenol-indophenol titration method. Antioxidant activity were determined using four antioxidant assays namely Ferric Reducing Antioxidant Potential (FRAP), Oxygen Radical Absorbance Capacity (ORAC), 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) and β-Carotene Bleaching Assays. For the TPC, puree with pH 3 (28.5±1.3 GAE/g fresh weight) exhibited high in TPC as compared to puree with pH 3.5 and unprocessed puree. In contrast, unprocessed puree contains significantly high ascorbic acid (AA) content (35.9 ± 1.8 mg/100 g fresh mass) as compared to pH 3.0 and pH 3.5 purees. In general, antioxidant activity for all assays of pH 3.0 and pH 3.5 purees were significantly higher (p

Matched MeSH terms: Phenols
Fulltext Nutritional profile and antioxidative properties of selected tropical wild vegetables

Ng, X.N., Chye, F.Y., Mohd Ismail, A.

International Food Research Journal, 2012;19(4):1487-1496.
MyJurnal

Five underutilized wild vegetables namely Limnophila aromaticoides, Ceratopetris thalictroides, Crassocephalum crepidioides, Etlingera elatoir and Monochoria vaginalis were analyzed for nutritional values, phenolic components and antioxidant activities. These wild greens were found to have high fibre (11.3-19.8 g/100g) and ash (13.0-17.6 g/100g) contents as compared to commercialized species, Brassica juncea. The iron content of Monochoria vaginalis is four times higher than Brassica juncea (33.1 mg/g dry weight). Crassocephalum crepidioides demonstrated remarkable lipid peroxidation inhibition (90.4%). The phenolic content of Etlingera elatoir is two times higher than Brassica juncea. Thus, it is of both great free radical scavenger and iron chelators with the lowest EC50 values of 1.8 mg/ml and 2.3 mg/ml respectively. As a conclusion, these wild vegetables could be potentially used in alleviating micronutrients deficiency especially for the rural populace and as a potent source of natural antioxidants.

Matched MeSH terms: Phenols
Fulltext Phytochemicals screening and total phenolic content of Malaysian Zea mays hair extracts

Solihah, M.A., Wan Rosli, W.I., Nurhanan, A.R.

International Food Research Journal, 2012;19(4):1533-1538.
MyJurnal

In the present study, Malaysian Zea mays hair extracts are screened for the occurrence of bioactive compounds. The results positively showed the present of flavonoids, saponin, tannins, phlobatannins, phenols, alkaloids and cardiac glycosides in both aqueous and methanolic extract of Zea mays hair. Terpenoid compounds however present only in the methanolic extract sample. In addition, the total phenolic content (TPC) in aqueous extract was significantly higher (42.71 + 0.87 µg/g of tannic acid equivalent (TAE)) compared to methanolic extract (40.38 + 1.10 µg/g of TAE). The findings suggested that phytochemicals present in Zea mays hair are potentially beneficial as therapeutic and antioxidative agents in pharmaceuticals, food and other related industries.

Matched MeSH terms: Phenols
Fulltext Antioxidant activity of winter melon (Benincasa Hispida) seeds using conventional soxhlet extraction technique

Mandana, B., Russly, A.R., Farah, S.T., Noranizan, M.A., Zaidul, I.S., Ali. G.

International Food Research Journal, 2012;19(1):229-234.
MyJurnal

In this study, the effect of different solvent including ethanol, n-hexane and ethyl acetate on antioxidant
activity and total phenolic content (TPC) of winter melon (Benincasa hispida) seeds extract was investigated using conventional Soxhlet extraction (CSE). DPPH and ABTS scavenging activity and TPC results indicated that the seed extracts obtained using ethanol possessed the highest antioxidant activity and followed by ethyl acetate and n-hexane. By considering obtained results, it was clear that there was a high positive correlation between TPC and antioxidant activity. Linoleic acid forms a significant percentage of unsaturated fatty acids of the seed extract (60.6%). It is well known that essential fatty acids including linoleic acid and linolenic acid which are detected in extracts play important roles in preventing many disease and abnormal differentiation problems. B. hispida seeds are potential source of natural antioxidant compounds to replace synthetic antioxidants.

Matched MeSH terms: Phenols
Fulltext Antioxidative properties of an extract of Hygrocybe conica, a wild edible mushroom

Khoo, H.E., Chong, E.L., Sia, C.M., Chang, S.K., Yim, H.S.

Malays J Nutr, 2014;20(1):101-111.
MyJurnal

Introduction: Hygrocybe conica (HC), a wild mushroom commonly consumed by the indigenous people (Orang Asli) in Peninsular Malaysia, was assessed for its antioxidant content. Methods: The HC mushroom was extracted using distilled water and the crude extract partitioned using different solvents and open column chromatography to evaluate its potential antioxidant properties. The mushroom extract was partitioned using liquid-liquid extraction into the hexane (Fl), chloroform (F2), butanol (F3) and formic acid (F4) fractions. Based on solvent polarity, the water extract of the mushroom was fractionated into non-polar (FI), semi-polar (Fii), and polar fractions (Fiii) using open column chromato graphy. Antioxidant capacities were determined using DPPH, ABTS, and ferric reducing antioxidant power (FRAP) assays while Folin-Ciocalteu reagent assay was used to determine total phenolic content (TPC). Results: The HC extract had the highest TPC and DPPH scavenging capacity compared to its extract fractions. TE values (ABTS assay) of F2 and F4 were not significantly higher than the HC extract. Among the extract fractions of different polarities, Fiii had the highest antioxidant capacities (DPPH and FRAP) compared to FI and Fii while FRAP values of these fractions were not significantly lower than the FRAP value of HC extract. The HC extract had significantly lower antioxidant capacity than antioxidant standards (ascorbic acid and BHA). Tannie acid as the main bioactive component in HC mushroom was detected using HPLC method. The presence of phenolics in HC extract was also confirmed using TLC. Conclusion: Due to the presence of potent phenolic components, the mycelia of HC could be consumed for potential antioxidative benefits.

Matched MeSH terms: Phenols
Fulltext Morphology observation and physical properties of phenolic resin-silicate layered nanocomposites

Norul Azlin, M.Z., Senin, H.B., Kok Sheng, C.

Journal of Nuclear and Related Technologies, 2009;2009(1):121-134.
MyJurnal

Phenolic resin-silica nanocomposites samples in pellet shape have been successfully prepared by intercalation of polymer solution through the hot pressing method. The phenolic resin is modified with organic elastomers of silica nanoparticles, which is about 20 nanometer in diameter. The change of density and porosity was studied based on the addition of silica content in the phenolic resin composites. The densities of composites increased with the addition of the silica content from 10 wt.% to 40 wt.%. On the other hand, the porosity percentage was decreased with increasing of silica contents. The mechanical properties (Young’s modulus, energy to break and time to failure) of the nanocomposites samples were identified using the Universal Testing Material Machine (UTM). The results of Young’s modulus, energy to break and time to failure of the phenolic resin composites were found to be slightly increased with silica content from 10 wt.% to 30 wt.%. The X-Ray Microtomogaphy (XRM) topographies have shown that the porosity exists on fracture structure for each nanocomposite. The nanocomposites surface structure has been analyzed using Scanning Electron Microscope (SEM). The observation shows that the fracture surface of the pure phenolic resin is relatively smooth and glassy, which is typical for a brittle material, but the phenolic resin- silica composites fracture surface is not smooth at all. The observations indicate the pure phenolic resin is brittle than phenolic resin-silica nanocomposites. Consequently, the physical properties of the phenolic resin-silica nanocomposites were improved with the addition of 10 wt.% to 30 wt.% silica contents, as compared to that of the pure phenolic resin.

Matched MeSH terms: Phenols
Fulltext Partial purification and characterization of polyphenol oxidase from round brinjal (S. melongena var. depressum)

Ng, A.W.R., Wong, C.W.

International Food Research Journal, 2015;22(2):826-831.
MyJurnal

Polyphenol oxidase (PPO) catalyzes the conversion of phenolic compounds into o-quinones which will lead to food browning. This phenomenon causes huge implications on food industries, as it degrades food quality over time. By combining both ammonium sulphate precipitation and gel filtration chromatography, PPO was partially purified up to 5.26-fold with 11.23% yield. The enzyme activity was 5120 EU/mL using 4-methylcatechol as substrate. Maximal PPO activity was found at 30oC, pH 5.0 for 4-methylcatechol and 40°C, pH 6.0 for catechol. The PPO showed a higher affinity towards 4-methylcatechol but higher thermal stability when reacting with catechol. The Km and Vmax values were 5.00 mM, 2000 EU/ml for 4-methylcatechol and 10.79 mM, 526.32 EU/ml for catechol. Energy for inactivation (Ea) obtained using 4-methylcatechol and catechol were 12.57 kJ/mol and 14.23 kJ/mol from respective substrates. Sodium disulfite was a better inhibitor where 79.17% of PPO inhibition was achieved. The isolation and characterization of round brinjal PPO serves as a guideline to predict the behavior of enzyme, leading to effective prevention of its browning during processing and storage.

Matched MeSH terms: Phenols

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