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Effect of filler and thermal aging on the mechanical properties of phenolated oil palm empty fruit bunch base composite

Ali Ahmadzadeh, Sarani Zakaria, Rozaidi Rasid, Sharifah Nabihah

Sains Malaysiana, 2008;37:233-237.

Biofiber is used in the polymer based composite as a renewable resource due to its positive environmental benefits, biodegradable properties, low cost and high toughness. Biocomposite was fabricated using oil palm empty fruit bunch (EFB) as filler in phenolated EFB (PEFB) matrix. Phenolated EFB (PEFB) obtained from liquefaction of EFB in phenol was used as a biopolymer to replace novolak phenolic resin which is commonly used in composite materials. Sulfuric acid was used as a catalyst in the liquefaction reaction. The effect of thermal aging and blending ratio of PEFB matrix and EFB fibers on the mechanical properties of composites has been studied. The flexural data before and after thermal aging revealed the optimum amount of EFB filler is 50% . The result showed better compatibility between EFB and PEFB when compared with EFB and commercial novolak resin.

Matched MeSH terms: Phenols
Response surface methodology optimization for extraction of phenolics and antioxidant capacity in defatted dabai parts

H-E. Khoo, Azlan A, Ismail A, Abas F

Sains Malaysiana, 2013;42:949-954.

This study aimed to determine the total phenolics and antioxidant capacity of defatted dabai parts based on liquid extraction and optimized using response surface methodology (RSM). A two-level factorial design was applied to determine the effect of two independent variables (extraction time: X1 and % methanol: X2) on three response variables (total phenolic content: Y1, total flavonoid/anthocyanin content: Y2 and Trolox equivalent antioxidant capacity: Y3). The optimum conditions for extraction time and percent methanol were 36 min or 1 min and 62.25% or 53% for the defatted dabai pulp or peel, respectively. The RSM optimized extraction was compared with sonication-assisted extraction. Optimization results showed that defatted dabai parts had high total phenolic content and antioxidant capacity. Sonication-assisted extraction utilized the optimized extraction conditions had further increased the total phenolic content and antioxidant capacity of defatted dabai peel, but not in the pulp. Therefore, optimization of different extraction methods for the defatted fruit parts is recommended for future studies.

Matched MeSH terms: Phenols
Fulltext Antioxidative and Quality Properties of Full-Fat Date Seeds Brew as Influenced by the Roasting Conditions

Fikry M, Yusof YA, M Al-Awaadh A, Abdul Rahman R, Chin NL, Ghazali HM

Antioxidants (Basel), 2019 Jul 18;8(7).
PMID: 31323854 DOI: 10.3390/antiox8070226

Full-fat roasted date seeds are considered an excellent source of antioxidants which can treat many diseases. The specific objectives were to investigate the effect of roasting temperature and time on the hardness of whole seeds, moisture content of the roasted date seeds powder, DPPH radical scavenging activity, total phenolic contents, extraction yield, pH, browning index and sensory properties of the brew prepared from the full-fat roasted date seeds and to construct descriptive models that could describe this effect. Date seeds were roasted at three temperatures (160, 180 and 200 °C) for different period of times (10, 20 and 30 min) using a natural conventional oven; then grinded and next brewed. Hardness of whole seeds, moisture content of the seeds powder, DPPH radical scavenging activity and total phenolic contents, extraction yield, pH and browning index and sensory properties of the brew were significantly affected by the roasting conditions. The statistical results indicated that the proposed model could adequately describe the measured properties. Strong correlations have been found among the properties of the brew as well. The producers of the date seeds brew can utilize these results for controlling the roasting process.

Matched MeSH terms: Phenols
Fulltext The Pharmacological Potential of Oil Palm Phenolics (OPP) Individual Components

Syarifah-Noratiqah SB, Zulfarina MS, Ahmad SU, Fairus S, Naina-Mohamed I

Int J Med Sci, 2019;16(5):711-719.
PMID: 31217739 DOI: 10.7150/ijms.29934

The oil palm tree (Elaeis guineensis) from the family Arecaceae is a high oil-producing agricultural crop. A significant amount of vegetation liquor is discarded during the palm oil milling process amounting to 90 million tons per year around the world. This water-soluble extract is rich in phenolic compounds known as Oil Palm Phenolics (OPP). Several phenolic acids including the three isomers of caffeoylshikimic acid (CFA), p-hydroxybenzoic acid (PHBA), protocatechuic acid (PCA) and hydroxytyrosol are among the primary active ingredients in the OPP. Previous investigations have reported several positive pharmacological potentials by OPP such as neuroprotective and atheroprotective effects, anti-tumor and reduction in Aβ deposition in Alzheimer's disease model. In the current review, the pharmacological potential for CFA, PHBA, PCA and hydroxytyrosol is carefully reviewed and evaluated.

Matched MeSH terms: Phenols/classification; Phenols/therapeutic use; Phenols/chemistry*
Facile synthesis of GO and g-C3N4 nanosheets encapsulated magnetite ternary nanocomposite for superior photocatalytic degradation of phenol

Rehman GU, Tahir M, Goh PS, Ismail AF, Samavati A, Zulhairun AK, et al.

Environ Pollut, 2019 Oct;253:1066-1078.
PMID: 31434184 DOI: 10.1016/j.envpol.2019.07.013

In this study, the synthesis of Fe3O4@GO@g-C3N4 ternary nanocomposite for enhanced photocatalytic degradation of phenol has been investigated. The surface modification of Fe3O4 was performed through layer-by-layer electrostatic deposition meanwhile the heterojunction structure of ternary nanocomposite was obtained through sonicated assisted hydrothermal method. The photocatalysts were characterized for their crystallinity, surface morphology, chemical functionalities, and band gap energy. The Fe3O4@GO@g-C3N4 ternary nanocomposite achieved phenol degradation of ∼97%, which was significantly higher than that of Fe3O4@GO (∼75%) and Fe3O4 (∼62%). The enhanced photoactivity was due to the efficient charge carrier separation and desired band structure. The photocatalytic performance was further enhanced with the addition of hydrogen peroxide, in which phenol degradation up to 100% was achieved in 2 h irradiation time. The findings revealed that operating parameters have significant influences on the photocatalytic activities. It was found that lower phenol concentration promoted higher activity. In this study, 0.3 g of Fe3O4@GO@g-C3N4 was found to be the optimized photocatalyst for phenol degradation. At the optimized condition, the reaction rate constant was reported as 6.96 × 10-3 min-1. The ternary photocatalyst showed excellent recyclability in three consecutive cycles, which confirmed the stability of this ternary nanocomposite for degradation applications.

Matched MeSH terms: Phenols
Fulltext Enhancement of Oil Palm Waste Nanoparticles on the Properties and Characterization of Hybrid Plywood Biocomposites

Nuryawan A, Abdullah CK, Hazwan CM, Olaiya NG, Yahya EB, Risnasari I, et al.

Polymers (Basel), 2020 Apr 27;12(5).
PMID: 32349385 DOI: 10.3390/polym12051007

Using oil palm trunk (OPT) layered with empty fruit bunch (EFB), so-called hybrid plywood enhanced with palm oil ash nanoparticles, with phenol-formaldehyde (PF) resin as a binder, was produced in this study. The phenol-formaldehyde (PF) resins filled with different loading of oil palm ash (OPA) nanoparticles were prepared and used as glue for layers of the oil palm trunk (OPT) veneer and empty fruit bunch fibre mat. The resulting hybrid plywood produced was characterised. The physical, mechanical, thermal, and morphological properties of the hybrid plywood panels were investigated. The results obtained showed that the presence of OPA nanoparticles significantly affected the physical, mechanical, and thermal properties of the plywood panels. Significant improvements in dimension from water absorption and thickness swelling experiments were obtained for the plywood panels with the highest OPA nanoparticles loading in PF resin. The mechanical properties indicated that plywood composites showed improvement in flexural, shear, and impact properties until a certain loading of OPA nanoparticles in PF resin. Fracture surface morphology also showed the effectiveness of OPA nanoparticles in the reduction of layer breakage due to force and stress distribution. The thermal stability performance showed that PF filled OPA nanoparticles contributed to the thermal stability of the plywood panels. Therefore, the results obtained in this study showed that OPA nanoparticles certainly improved the characteristic of the hybrid plywood.

Matched MeSH terms: Phenols
Metabolomic analysis reveals the valuable bioactive compounds of Ardisia elliptica

Wong PL, Ramli NS, Tan CP, Azlan A, Abas F

Phytochem Anal, 2021 Sep;32(5):685-697.
PMID: 33295100 DOI: 10.1002/pca.3015

INTRODUCTION: Ardisia elliptica Thunb. (Primulaceae) is a medicinal herb that is traditionally used for the treatment of fever, diarrhoea, measles and herpes. However, there is limited information regarding the correlation of its phytoconstituents with the bioactivity. Optimisation of solvent extraction is vital for maximising retention of bioactive molecules.
OBJECTIVE: This study investigated the metabolite variations in A. elliptica leaves and the correlation with antioxidant activities.
METHODOLOGY: Total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO) radicals scavenging assays were performed on A. elliptica leaves extracted with four different ethanol ratios (0%, 50%, 70% and absolute ethanol). The correlation of metabolites with antioxidant activities was evaluated using a nuclear magnetic resonance (NMR)-based metabolomics approach.
RESULTS: The results showed that the 50% and 70% ethanolic extracts retained the highest TPC, and the 70% ethanolic extract was the most active, exhibiting half maximal inhibitory concentration (IC50 ) values of 10.18 ± 0.83 and 43.05 ± 1.69 μg/mL, respectively, in both radical scavenging assays. A total of 46 metabolites were tentatively identified, including flavonoids, benzoquinones, triterpenes and phenolic derivatives. The 50% and 70% ethanolic extracts showed similarities in metabolites content and were well discriminated from water and absolute ethanol extracts in a principal component analysis (PCA) model. Moreover, 31 metabolites were found to contribute significantly to the differentiation and antioxidant activity.
CONCLUSION: This study provides information on bioactive compounds in A. elliptica leaves, which is promising as a functional ingredient for food production or for the development of phytomedicinal products.

Matched MeSH terms: Phenols
Fulltext Review on the pharmacology and chemical analysis of the olives

Ab Muib, N. N., Mohsin, H. F., Abdul Wahab, I.

Journal of Academia Universiti Teknologi MARA Negeri Sembilan, 2020;8(1):29-33.
MyJurnal

Olive or Olea europaea is originated from Mediterranean and cultivated in different regions of the world.
Each part of the plant has its own unique botanical description and gives a lot of benefits, either for
biological or common uses. In this research, the pharmacological properties of O. europaea were studied
via literature reviews. In the laboratory, the extraction of secondary metabolites from the dried leaves of O.
europaea was followed by the chromatographic investigation. The biological uses of O. europaea and
detection of the phenolics from olive leaves are highlighted. Specifically, oleuropein is the targeted
compound worth to be further analyzed.

Matched MeSH terms: Phenols
Fulltext Acceptability of novel antioxidant ice cream fortified with nutritous Carica papaya seed

Siti Radhiah Omar, Fauzan Aminuddin, Latiffah Karim, Nursyahida Suhaimi, Siti Nazirah Omar

Journal of Academia Universiti Teknologi MARA Negeri Sembilan, 2020;8(1):7-17.
MyJurnal

This research aimed to determine the total antioxidant activity and total phenolic content of the papaya
seeds. These papaya seeds then were introduced into the prepared ice cream to determine the effect of the
papaya seeds to the physicochemical and the acceptability of ice cream by making four different
formulations (Control, 1.0%, 2.0%, and 3.0% of papaya seeds). Two methods namely free radical
scavenging assay (DPPH) and ferric reducing antioxidant power (FRAP) were used to determine the total
antioxidant activity of the papaya seeds, whereas total phenolic content was determined by FolinCiocalteu’s method (TPC). The papaya seeds showed high total phenolic content in the TPC analysis result.
Furthermore, DPPH and FRAP showed high antioxidant activity of the papaya seeds. Acceptability of the
ice cream was conducted by sensory evaluation and the results showed that the control (0.0%) papaya seeds
ice cream formulation was the most favorable by the panelists followed by 1.0%, 2.0%, and 3.0% papaya
seeds formulation. In conclusion, the papaya seeds are proven to contain antioxidants by the results given
in DPPH, FRAP, and TPC tests. Surprisingly, the papaya seeds also did not affect the physicochemical of
the ice cream and the ice cream was accepted by the panelists.

Matched MeSH terms: Phenols
Online preconcentration by electrokinetic supercharging for separation of endocrine disrupting chemical and phenolic pollutants in water samples

Abdul Karim N', Wan Ibrahim WA, Sanagi MM, Abdul Keyon AS

Electrophoresis, 2016 10;37(20):2649-2656.
PMID: 27434368 DOI: 10.1002/elps.201600207

Online preconcentration using electrokinetic supercharging (EKS) was proposed to enhance the sensitivity of separation for endocrine disrupting chemical (methylparaben (MP)) and phenolic pollutants (2-nitrophenol (NP) and 4-chlorophenol (CP)) in water sample. Important EKS and separation conditions such as the concentration of BGE; the choice of terminating electrolyte (TE); and the injection time of leading electrolyte (LE), sample, and TE were optimized. The optimum EKS-CE conditions were as follows: BGE comprising of 12 mM sodium tetraborate pH 10.1, 100 mM sodium chloride as LE hydrodynamically injected at 50 mbar for 30 s, electrokinetic injection (EKI) of sample at -3 kV for 200 s, and 100 mM CHES as TE hydrodynamically injected at 50 mbar for 40 s. The separation was conducted at negative polarity mode and UV detection at 214 nm. Under these conditions, the sensitivity of analytes was enhanced from 100- to 737-fold as compared to normal CZE with hydrodynamic injection, giving LOD of 4.89, 5.29, and 53 μg/L for MP, NP and CP, respectively. The LODs were adequate for the analysis of NP and CP in environmental water sample having concentration at or lower than their maximum admissible concentration limit (240 and 2000 μg/L for NP and CP). The LOD of MP can be suitable for the analysis of MP exists at mid-microgram per liter level, even though the LOD was slightly higher than the concentration usually found in water samples (from ng/L to 1 μg/L). The method repeatabilities (%RSD) were in the range of 1.07-2.39% (migration time) and 8.28-14.0% (peak area).

Matched MeSH terms: Phenols/analysis; Phenols/isolation & purification*; Phenols/chemistry
Fulltext Fluorescence characteristics of 3-nitro-2-phenoxypyridine and 3-nitro-2(4-methyl)phenoxypyridine

Abdullah, Z., Halim, Z.I.A., Bakar, M.A.A., Idris, A.M.

ASM Science Journal, 2009;3(1):39-44.
MyJurnal

3-Nitro-2-phenoxypyridine and 3-nitro-2-(4-methyl)phenoxypyridine were obtained when 2-chloro-3-nitropyridine was treated with phenol and p-cresol, respectively. Fluorescence studies were carried out in various solvents, in capped and uncapped conditions and for differing concentrations. Both 3-nitro-2-phenoxypyridine and 3-nitro-2-(4-methyl)phenoxypyridine were fluorescent compounds but 3-Nitro-2-(4-methyl)phenoxypyridine was more fluorescent than 3-nitro-2-phenoxypyridine in all the solvents used. The fluorescence intensity decreased with concentration and time.

Matched MeSH terms: Phenols
Fulltext Phytochemicals and antioxidant properties of different parts of Camellia sinensis leaves from Sabah Tea Plantation in Sabah, Malaysia

Nor Qhairul Izzreen, M.N., Mohd Fadzelly, A.B.

International Food Research Journal, 2013;20(1):307-312.
MyJurnal

This study was conducted to determine the total phenolic (TPC) and total flavonoid content (TFC) as well as the antioxidant activity of 50% ethanolic extracts from different parts of Camellia sinensis (shoot, young and matured leaves). Comparison was also made between black (fermented) and green (unfermented) tea. For green tea, the results showed that the shoot contained significantly higher total phenolic content, followed by the young and matured leaves (p

Matched MeSH terms: Phenols
Fulltext Effect of solid-to-solvent ratio on phenolic content and antioxidant capacities of “Dukung Anak” (Phyllanthus niruri)

Wong, B.Y., Tan, C.P., Ho, C.W.

International Food Research Journal, 2013;20(1):325-330.
MyJurnal

The objective of this study was to evaluate the effects of solid-to-solvent ratio (1:5. 1:10, 1:15 and 1:20) on the extraction of phenolic compounds (TPC and TFC) and antioxidant capacity (ABTS and DPPH radical scavenging capacity) of P. niruri. Solid-to-solvent ratio showed a significant effect for both phenolic compounds (TPC and TFC) and antioxidant capacity (ABTS and DPPH radical scavenging capacity) with 1:20 was the condition for extracting the highest of phenolic compounds (TPC and TFC) with a value of 5788.7 mg GAE/100 g DW and 1906.5 mg CE/100 g DW, respectively and exhibited high antioxidant capacities (ABTS and DPPH radical scavenging capacities) with a value of 0.820 mM and 1.598 mM, respectively among the four levels studied. TPC was positively and significantly correlated with ABTS and DPPH (r=0.999 and r=0.999) under the effects of solid-to-solvent ratio as compared to TFC, positively and strongly correlated (r=0.865 and r=0.868) with ABTS and DPPH.

Matched MeSH terms: Phenols
Fulltext Optimisation of extraction conditions for phenolic compounds from limau purut (Citrus hystrix) peels

Chan, S.W., Lee, C.Y., Yap, C.F., Wan Aida, W.M., Ho, C.W.

International Food Research Journal, 2009;16(2):203-213.
MyJurnal

The objective of this study was to optimise the extraction conditions for phenolic compounds from limau purut (Citrus hystrix) peels using response surface methodology (RSM). A central composite rotatable design (CCRD) was applied to determine the effects of ethanol concentration (%), extraction temperature (oC), and extraction time (min) on total phenolic content (TPC) from limau purut (Citrus hystrix) peels. The independent variables were coded at five levels and their actual values were selected based on the results of single factor experiments. Results showed that ethanol concentration was the most significant (p

Matched MeSH terms: Phenols
Fulltext Total phenolics, flavonoids and antioxidant activity of banana pulp and peel flours: influence of variety and stage of ripeness

Fatemeh, S. R., Saifullah, R., Abbas, F. M. A., Azhar, M. E.

International Food Research Journal, 2012;19(3):1041-1046.
MyJurnal

The influence of variety (Cavendish and Dream), stage of ripeness (green and ripe) and parts (pulp and peel) on antioxidative compounds and antioxidant activity of banana fruit was investigated. The TPC and TFC ranged widely from 75.01 to 685.57 mg GAE/100 g and 39.01 to 389.33 mg CEQ/100 g of dry matter respectively. Cavendish banana flour contained higher TPC and TFC compared to Dream variety. TPC and TFC values of banana peel were higher than those of banana pulp. Also, green banana showed higher TPC and TFC values than those of ripe fruit. Radical scavenging activities (inhibition of DPPH) of the extracts ranged from 26.55 to 52.66%. Although Dream banana peel extracts appeared to have low TPC and TFC, its antioxidant activities were ranked moderate to high. This implies that antioxidative compounds other than phenolics and flavonoids were probably responsible for inhibition of DPPH.

Matched MeSH terms: Phenols
Determination of pitaya seeds as a natural antioxidant and source of essential fatty acids

Chemah, T.C., Aminah, A., Noriham, A., Wan Aida, W.M.

International Food Research Journal, 2010;17(4):1003-1010.
MyJurnal

The antioxidant capacity and total phenolic content of seeds of three types of pitaya namely Hylocereus polyrhizus, Hylocereus undatus and Selenicereus megalanthus and the fatty acid content of pitaya seeds oil were examined in this study. The ethanolic extracts of H. polyrhizus seeds showed significantly high (p

Matched MeSH terms: Phenols
Fulltext Influence of ripening stages on physicochemical characteristics and antioxidant properties of bitter gourd (Momordica charantia)

Aminah, A., Anna, P.K.

International Food Research Journal, 2011;18(3):-.
MyJurnal

Momordica charantia is known to contain with antioxidant properties and bioactive compounds to lower of diabetic diseases. Objective this study was investigate the influence of ripening stages on the phenolic bioactive substances and the corresponding antioxidant activity of bitter melon (Momordica charantia). The ripening of bitter melon fruit divided to four stages (RS1, RS2, RS3 and RS4). The results of this study were more ripened the fruit, lightness (L * ), yellowish (b * ) and chroma increased. Other ways, more ripened the fruit, the pH value and titratable acidity decreased. Total phenolic content and FRAF of RS 4 was highest compared other samples but DPPH of RS 4 was lowest among all the samples. However DPPH and FRAP value of bitter gourd on ripening stages showed no significant difference (p>0.05) among samples.

Matched MeSH terms: Phenols
Fulltext Optimization of extraction conditions for phenolic compounds from neem (Azadirachta indica) leaves

Hismath, I., Wan Aida, W. M., Ho, C.W.

International Food Research Journal, 2011;18(3):-.
MyJurnal

The objective of this study was to optimise the extraction conditions for phenolic compounds from neem (Azadirachta indica) leaves using response surface methodology (RSM). A central composite rotatable design (CCRD) was applied to determine the effects of acetone concentration (%), extraction time (mins), and extraction temperature ( o C) on total phenolic content (TPC) from neem (Azadirachta indica) leaves. The independent variables were coded at five levels and their actual values were selected based on the results of single factor experiments. Results showed that acetone concentration and extraction time were the most significant (p

Matched MeSH terms: Phenols
Antioxidant properties of methanolic extract of Canarium odontophyllum fruit

Azrina, A., Nurul Nadiah, M.N., Amin, I.

International Food Research Journal, 2010;17(2):319-326.
MyJurnal

The antioxidant properties of skin, flesh and kernel of Canarium odontophyllum fruit were determined. The methanolic extracts of the fruit were screened for their total phenolic content and antioxidant properties. The averaged antioxidant properties (mM TE/g FM) in skin, flesh, and kernel of Canarium odontophyllum were 16.46 ± 0.24, 20.54 ± 0.35, and 8.89 ± 0.29, respectively by DPPH assay; 151.24 ± 9.75, 70.58 ± 2.98, and 5.65 ± 0.02, respectively by FRAP assay; and 47.9 ± 0.00, 11.61 ± 1.14, and 3.00 ± 0.00, respectively by β-Carotene bleaching method. The averaged OH scavenging activity (mg DMSOE/mg FM) in skin, flesh, and kernel of Canarium odontophyllum were 43.33 ± 13.85, 7.81 ± 1.42, and 3.31 ± 0.80, respectively. While averaged total phenolic content (mg GAE/100g FM) were 387.5 ± 33.23, 267.0 ± 4.24, and 51.0 ± 0.00 for skin, flesh, and kernel respectively. Antioxidant activities were positively correlated with the total phenolic content (0.71 ≤ r ≤ 0.84).

Matched MeSH terms: Phenols
Antioxidant study of pulps and peels of dragon fruits: a comparative study

Nurliyana, R., Syed Zahir, I., Mustapha Suleiman, K., Aisyah, M.R., Kamarul Rahim, K

International Food Research Journal, 2010;17(2):367-375.
MyJurnal

The aim of this study is to compare antioxidant level and activities (i.e. primary and secondary) in pulps and peels of two species of dragon fruits, Hylocereus undatus (white dragon fruit) and Hylocereus polyrhizus (red dragon fruit). Total phenolic content (TPC) assay demonstrated that peels of both Hylocereus species contained higher phenolic content than the pulps. The phenolic content in peels of H. undatus was higher than H. polyrhizus, but the phenolic content in pulps of H. undatus was much lower than H. polyrhizus. 2, 2, diphenyl-1-picrylhydrazyl (DPPH) assay showed that radical scavenging activities of peels for both species were higher than the pulps. For ferrous ion chelating (FIC) assay, peels and pulps of both Hylocereus species showed moderate metal ion chelating effect as compared to EDTA. Overall, the results suggested that the TPC showed good relationship with the primary antioxidant activities for general comparison between the peels and the pulps.

Matched MeSH terms: Phenols

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