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Background: Silkworm protein applications are limited in the food industry because of their low emulsifying and foaming properties. This study investigated the effect of ultrasound-assisted extraction (UAE) for 15 and 30 min, microwave-assisted extraction (MAE) for 1 and 2 min, and freeze-thaw-assisted extraction (FTAE) for one and three cycles on the yield, extraction efficiency, functional properties, and antioxidant activities of proteins from silkworm pupae. Relationships of protein structure and functionality were also examined., Results: UAE for 15 and 30 min and MAE for 1 and 2 min significantly increased protein yield and extraction efficiency compared to the control. Both UAE and MAE processes, especially MAE for 2 min, greatly improved the emulsifying and foaming properties of extracted proteins. FTAE one and three cycles did not increase the protein yield and extraction efficiency but showed enhanced functional properties, especially foaming. All samples showed changes in protein structure, such as increased exposed sulfhydryl (SH) contents, denaturation temperatures, and enthalpy. Only MAE samples had low-molecular-weight proteins based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. UAE and FTAE samples had significantly higher antioxidant activities, while the MAE process showed the opposite., Conclusion: UAE and MAE processes improved the yield and functionality of extracted silkworm proteins, while MAE negatively impacted protein antioxidant activities. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

Allium ampeloprasum L., commonly known as wild leek, is an edible vegetable that has been cultivated for centuries. However, no detailed studies have been undertaken to valorize A. ampeloprasum seed oil. This study aims to evaluate the physicochemical properties, chemical composition, and antioxidant activity of A. ampeloprasum seed oil. The seed oil content was found to be 18.20%. Gas chromatographymass spectrometry (GC-MS) showed that linoleic acid (71.65%) was the dominant acid, followed by oleic acid (14.11%) and palmitic acid (7.11%). A. ampeloprasum seed oil exhibited an oxidative stability of 5.22 h. Moreover, γ- and δ-tocotrienols were the major tocols present (79.56 and 52.08 mg/100 g oil, respectively). The total flavonoid content (16.64 µg CE /g oil) and total phenolic content (62.96 µg GAE /g oil) of the seed oil were also determined. The antioxidant capacity of the oil, as evaluated using the ABTS assay (136.30 µM TEAC/g oil), was found to be significant. These findings indicate that A. ampeloprasum seeds can be regarded as a new source of edible oil having health benefits and nutritional properties.

Claims of effective therapy against diabetes using plants including Peganum harmala L., Zygophyllum album, Anacyclus valentinus L., Ammodaucus leucotrichus, Lupinus albus , and Marrubium vulgare in Algerian empirical medicine prompted our interest in evaluating their antidiabetic activity by screening their free radical scavenging (DPPH), α-glucosidase, and nitric oxide (NO) inhibitory activities as well as the total phenolic content (TPC). Extracts of the selected plants were prepared using different ratios of ethanol (0, 50, 80, and 100%). In this study, 100%, and 80% ethanol extracts of L. albus were found to be the most potent, in inhibiting α-glucosidase activity with IC 50 values of 6.45 and 8.66 μg/mL, respectively. The 100% ethanol extract of A. leucotrichus exhibited the highest free radical scavenging activity with an IC 50 value of 26.26 μg/mL. Moreover, the highest TPC of 612.84 μg GAE/mg extract was observed in M. vulgare , extracted with 80% ethanol. Metabolite profiling of the active extract was conducted using 1 H-NMR metabolomics. Partial least square analysis (PLS) was used to assess the relationship between the α-glucosidase inhibitory activity of L. albus and the metabolites identified in the extract. Based on the PLS model, isoflavonoids (lupinoisoflavone G, lupisoflavone, lupinoisolone C), amino acids (asparagine and thiamine), and several fatty acids (stearic acid and oleic acid) were identified as metabolites that contributed to the inhibition of α-glucosidase activity. The results of this study have clearly strengthened the traditional claim of the antihyperglycemic effects of L. albus.

Kenaf seed oil-in-water nanoemulsions (NANO) stabilized by sodium caseinate (SC), beta-cyclodextrin (β-CD), and Tween 20 (T20) have been optimized and shown to improve in vitro bioaccessibility and physicochemical stability in the previous study. The main objective of this study was to evaluate the stability of bioactive compounds and antioxidants in the NANO during storage at different temperatures (4 °C, 25 °C, and 40 °C). An evaluation of the antioxidant activities of each emulsifier showed that SC had good scavenging capability with 97.6% ABTS radical scavenging activity. Therefore, SC which was used as one of the main emulsifiers could further enhanced the antioxidant activity of NANO. At week 8 of storage, NANO that stored at 4 °C had maintained the best bioactive compounds stability and antioxidant activities with 90% retention of vitamin E and 65% retention of phytosterols. These results suggested that 4 °C would be the most suitable storage temperature for NANO containing naturally present vitamin E and phytosterols. From the accelerated storage results at 40 °C, NANO containing vitamin E and phytosterols had maintained half of its initial concentration until week 4 and week 2 of storage, which is equivalent to 16 weeks and 8 weeks of storage at room temperature, respectively., Practical Application: The results of this study provide a better understanding on the stability of bioactive compounds and antioxidant activities in oil-in-water nanoemulsions that stabilized by similar ternary emulsifiers during storage at different temperatures. In addition, this study could be used as a predictive model to estimate the shelf life of bioactive compounds encapsulated in the form of nanoemulsions., (© 2018 Institute of Food Technologists®.)

The solubility limitations of phenolic acids in many lipidic environments are now greatly improved by their enzymatic esterification in ionic liquids (ILs). Herein, four different ILs were tested for the esterification of dihydrocaffeic acid with hexanol and the best IL was selected for the synthesis of four other n-alkyl esters with different chain-lengths. The effect of alkyl chain length on the anti-oxidative properties of the resulted purified esters was investigated using β-carotene bleaching (BCB) and free radical scavenging method DPPH and compared with butylated hydroxytoluene (BHT) as reference compound. All four esters (methyl, hexyl, dodecyl and octadecyl dihydrocaffeates) exhibited relatively strong radical scavenging abilities. The scavenging activity of the test compounds was in the following order: methyl ester>hexyl ester⩾dodecyl ester>octadecyl ester>BHT while the order for the BCB anti-oxidative activity was; BHT>octadecyl ester>dodecyl ester>hexyl ester>methyl ester., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The objective of this research was to study the oxidative stability and antioxidant properties of microencapsulated kenaf (Hibiscus cannabinus L.) seed oil (MKSO) produced by co-extrusion technology upon accelerated storage. The combination of sodium alginate, high methoxyl pectin, and chitosan were used as shell materials. The oxidative stability of the kenaf seed oil was determined by iodine value, peroxide value, p-Anisidine value, total oxidation (TOTOX), thiobarbituric acid reactive substances assay, and free fatty acid content. Total phenolic content, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) cation radical-scavenging assay and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay were used to examine the antioxidant properties of oils. Oxidative stability tests showed that bulk kenaf seed oil (BKSO) was oxidized significantly higher (P < 0.05) than MKSO. The total increment of TOTOX value of BKSO was 165.93% significantly higher (P < 0.05) than MKSO. Co-extrusion technology has shown to be able to protect kenaf seed oil against lipid oxidation and delay the degradation of natural antioxidants that present in oil during storage., (© 2016 Institute of Food Technologists®.)

The study investigated the changes in the metabolite, antioxidant and α-glucosidase inhibitory activities of Phyllanthus niruri after three drying treatments: air, freeze and oven dryings. Water extracts and extracts obtained using different solvent ratios of ethanol and methanol (50, 70, 80 and 100%) were compared. The relationships among the antioxidant, α-glucosidase inhibitory activity and metabolite levels of the extracts were evaluated using partial least-square analysis (PLS). The solvent selectivity was assessed based on the phytochemical constituents present in the extract and their concentrations quantitatively analyzed using high performance liquid chromatography. The freeze-dried P. niruri samples that were extracted with the mixture of ethanol or methanol with low ratio of water showed higher biological activity values compared with the other extracts. The PLS results for the ethanolic with different ratio and water extracts demonstrated that phenolic acids (chlorogenic acid and ellagic acid) and flavonoids were highly linked to strong α-glucosidase inhibitory and antioxidant activities.

The aim of this study was to determine the best parameter for extracting phenolic-enriched kenaf (Hibiscus cannabinus L.) seeds by a pulsed ultrasonic-assisted extraction. The antioxidant activities of ultrasonic-assisted kenaf seed extracts (KSE) were determined by a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging assay, β -carotene bleaching inhibition assay, and ferric reducing antioxidant power (FRAP) assay. Total phenolic content (TPC) and total flavonoid content (TFC) evaluations were carried out to determine the phenolic and flavonoid contents in KSE. The KSE from the best extraction parameter was then subjected to high performance liquid chromatography (HPLC) to quantify the phenolic compounds. The optimised extraction condition employed 80% ethanol for 15 min, with the highest values determined for the DPPH, ABTS, and FRAP assay. KSE contained mainly tannic acid (2302.20 mg/100 g extract) and sinapic acid (1198.22 mg/100 g extract), which can be used as alternative antioxidants in the food industry.

The protective effects of α-tocopherol and ascorbic acid on astaxanthin in astaxanthin nanodispersions produced via a solvent-diffusion technique and stabilized by a three-component stabilizer system, were studied either individually or in combination by using response surface methodology. Generally, both α-tocopherol and ascorbic acid could retard the astaxanthin degradation in astaxanthin nanodispersions. The results showed that the using α-tocopherol and ascorbic acid can be more efficient in increasing the chemical stability of nanodispersions in comparison to using them individually. Using a response surface methodology (RSM) response optimizer, it was seen that addition of ascorbic acid (ascorbic acid/astaxanthin w/w) and α-tocopherol (α-tocopherol/astaxanthin w/w) in proportions of 0.4 and 0.6, respectively, would give the maximum chemical stability to the studied astaxanthin nanodispersions.

Antioxidants have been widely used in the food industry to enhance product quality by preventing oxidation of susceptible substances. This work was carried out to maximise the recovery of total phenolic content (TPC), total flavonoid content (TFC), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical-scavenging capacity and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity from Morinda citrifolia fruit via modification of the ethanol concentration, extraction time and extraction temperature at minimal processing cost. The optimised conditions yielded values of 881.57 ± 17.74 mg GAE/100 g DW for TPC, 552.53 ± 34.16 mg CE/100 g DW for TFC, 799.20 ± 2.97 µmol TEAC/100 g DW for ABTS and 2,317.01 ± 18.13 µmol TEAC/100 g DW for DPPH were 75% ethanol, 40 min of time and 57 °C. The four responses did not differ significantly (p > 0.05) from predicted values, indicating that models obtained are suitable to the optimisation of extraction conditions for phenolics from M. citrifolia. The relative amounts of flavonoids were 0.784 ± 0.01 mg quercetin/g of extract and 1.021 ± 0.04 mg rutin/g of extract. On the basis of the results obtained, M. citrifolia extract can be used as a valuable bioactive source of natural antioxidants.

The synergistic antioxidant effects of ethanolic extracts of Centella asiatica (CE), and α-tocopherol have been studied. The types of interactions exhibited by CE and α-tocopherol combined at different ratios were measured using three assays: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical-scavenging capacity, the β-carotene bleaching system and liposome peroxidation assays. Fixed-fraction isobolographic analysis was used to detect any inducement of the antioxidant activity compared with the individual activities of CE and α-tocopherol. Of all synergistic combinations of CE and α-tocopherol, only fraction 2/3 showed the synergistic combination that fits well in three different assays and can be explained by the regeneration of α-tocopherol by CE despite the interaction effect of β-carotene present in the analytical assay. This phenomenon involved complex interactions between CE and α-tocopherol to exhibit different degrees of interactions that eventually increased antioxidant activity., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Astaxanthin colloidal particles were produced using solvent-diffusion technique in the presence of different food grade surface active compounds, namely, Polysorbate 20 (PS20), sodium caseinate (SC), gum Arabic (GA) and the optimum combination of them (OPT). Particle size and surface charge characteristics, rheological behaviour, chemical stability, colour, in vitro cellular uptake, in vitro antioxidant activity and residual solvent concentration of prepared colloidal particles were evaluated. The results indicated that in most cases the mixture of surface active compounds lead to production of colloidal particles with more desirable physicochemical and biological properties, as compared to using them individually. The optimum combination of PS20, SC and GA could produce the astaxanthin colloidal particles with small particle size, polydispersity index (PDI), conductivity and higher zeta potential, mobility, cellular uptake, colour intensity and in vitro antioxidant activity. In addition, all prepared astaxanthin colloidal particles had significantly (p<0.05) higher cellular uptake than pure astaxanthin powder., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Abstract: Kenaf seed oil is prone to undergo oxidation due to its high content of unsaturated fatty acids, thus microencapsulation stands as an alternative to protect kenaf seed oil from the adverse environment. This study primarily aimed to evaluate the oxidative stability of microencapsulated refined kenaf seed oil (MRKSO) by the use of gum arabic, β‐cyclodextrin, and sodium caseinate as the wall materials by spray drying. Bulk refined kenaf seed oil (BRKSO) and MRKSO were kept at 65 °C for 24 days to evaluate its oxidative stability, changes of tocopherol and tocotrienol contents, phytosterol content, and fatty acid profile. The results showed that the peroxide value, p‐Anisidine value, and total oxidation value of BRKSO were significantly higher than the MRKSO at day 24. The total tocopherol and tocotrienol contents were reduced 66.1% and 56.8% in BRKSO and MRKSO, respectively, upon the storage. There was a reduction of 71.7% and 23.5% of phytosterol content in BRKSO and MRKSO, respectively, upon the storage. The degradation rate of polyunsaturated fatty acids in BRKSO was higher than that of MRKSO. This study showed that the current microencapsulation technique is a feasible way to retard the oxidation of kenaf seed oil. Practical Application: There is increasing research on the functional properties of crude kenaf seed oil, but the crude kenaf seed oil is not edible. This study offered in developing of microencapsulated refined kenaf seed oil by spray drying, which is suitable for food application. The microencapsulation of refined kenaf seed oil with healthier wall materials is beneficial in developing a diversity of functional food products and supplements. [ABSTRACT FROM AUTHOR]

Red palm oil (RPO) is a natural source of Vitamin E (70–80% tocotrienol). It is a potent natural antioxidant that can be used in skin-care products. Its antioxidant property protects skin from inflammation and aging. In our work, a tocotrienol-rich RPO-based nanoemulsion formulation was optimized using response surface methodology (RSM) and formulated using high pressure homogenizer. Effect of the concentration of three independent variables [surfactant (5–15 wt%), co-solvent (10–30 wt%) and homogenization pressure (500–700 bar)] toward two response variables (droplet size, polydispersity index) was studied using central composite design (CCD) coupled to RSM. RSM analysis showed that the experimental data could be fitted into a second-order polynomial model and the coefficients of multiple determination (R2) is 0.9115. The optimized formulation of RPO-based nanoemulsion consisted of 6.09 wt% mixed surfactant [Tween 80/Span 80 (63:37, wt)], 20 wt% glycerol as a co-solvent via homogenization pressure (500 bar). The optimized tocotrienol-rich RPO-based nanoemulsion response values for droplet size and polydispersity index were 119.49nm and 0.286, respectively. The actual values of the formulated nanoemulsion were in good agreement with the predicted values obtained from RSM, thus the optimized compositions have the potential to be used as a nanoemulsion for cosmetic formulations. [ABSTRACT FROM AUTHOR]

Microencapsulation is an excellent substitute in the transformation of liquid food into stabilised powder. The objective of the present study was to examine the influence of process conditions on microencapsulation of Nigella sativa oil using spray drying, by applying the response surface methodology (RSM) by central composite design. The independent variables were: the content of wall material (10–30%), the concentration of oil (10–30%) and temperature (150–190 °C of inlet air drying). The microencapsulation efficiency, moisture content, solubility, particle size, total phenolic content (TPC), and antioxidant activity by 1,1-diphenyl-picryl-hydrazyl (DPPH) were analysed as responses. Powders were gauged by a complete 2 3 central composite rotatable design. The optimal conditions were determined to be 30% wall material, 10% concentration of oil, and 160 °C drying inlet air temperature. The optimised spray-dried powder had high values for MEE (92.71%), solubility (91.38%), and total phenolic content TPC (137.68 mg/100 g) as well as low values of DPPH (IC 50 of 1.61 mg/g), moisture content (1.03%), and particle size (15.516 μm). [ABSTRACT FROM AUTHOR]

Kenaf seed oil-in-water nanoemulsions stabilised by sodium caseinate, Tween 20 and β-cyclodextrin complexes were produced using high pressure homogeniser. This formulation has been shown to possess good lipid digestion and increased bioaccessibility of tocopherols and total phenolic contents. However, its physicochemical and oxidative stability during storage was unknown. Therefore, the main objectives of this study were to evaluate the effects of three storage temperatures (4 °C ± 2 °C, 25 °C ± 2 °C and 40 °C ± 2 °C) on the physicochemical, oxidative and antioxidant stability of formulated kenaf seed oil-in-water nanoemulsions. The results showed that nanoemulsions stored at 4 °C had maintained the highest stability with the highest zeta-potential value (−36.6 mV), lowest changes of PDI and pH over 12 weeks of storage. It also presented the lowest reduction of polyunsaturated fatty acids (PUFA) over the course of storage period. In contrast, nanoemulsions that stored at 40 °C exhibited lowest stability with the lowest zeta-potential (−27.3 mV). Sediment was observed in 8 weeks of storage and it had the highest reduction of PUFA. Total phenolic contents in nanoemulsions that stored at 4 °C and 25 °C showed decreasing trend during the storage period, except for nanoemulsions that stored at 40 °C showed a significant increase (p < 0.05) in the first week of storage, but subsequently also displayed decreasing trend. The overall results showed that nanoemulsions that stored at 4 °C and 25 °C were stable for up to 8 weeks of storage. Nanoemulsions that stored under accelerated storage temperature of 40 °C were stable for 1 week, which is equivalent to 28 days at room temperature (RT) based on Arrhenius equation. The results of this study could provide better understanding of the storage stability of kenaf seed oil-in-water nanoemulsions under different storage temperatures. It could be served as a predictive model to estimate its shelf-life. [ABSTRACT FROM AUTHOR]

Maillard reaction products (MRPs) are believed to possess antioxidant property besides producing emulsion which is stable and smaller in size. In our work, utilization of MRP as encapsulating agent for structured lipid palm-based medium- and long-chain triacylglycerol (MLCT) was investigated. The MRP prepared from heated aqueous mixture of sodium caseinate (SC), soy protein (SP) and maltodextrin (M) was emulsified with MLCT prior spray drying. The effect of temperature (20, 40, 60, 80, 100 °C), incubation time (2, 6, 8 h), mixture of SC: SP: M (1:0:1, 2:1:3, 1:1:2, 1:2:3, 0:1:1) and carbohydrate + protein:water ratio (1:5 and 1:8) on glycation was investigated. Degree of glycation (Dg) was determined via amount of block amino acid and L*a*b* value. As expected, increasing heat treatment (20, 40, 60, 80, 100 °C) and incubation time (2, 6 and 8 h) significantly ( P < 0.05) increase the Dg. Dg was also higher ( P < 0.05) at high water to solid content. Subsequently, the influence of Dg on physical properties of emulsion and spray-dried powder was also evaluated. It was found that glycation has the ability to reduce the emulsion size besides lowering moisture and surface oil content and creating larger microparticle size of the spray-dried powder. Nonetheless, whitening ability and solubility of the powder are slightly reduced especially when 100 °C MRP was used for encapsulation. SEM showed that glycation resulted in particle with smoother surface. MRP can be utilized as natural emulsifier besides improving certain functional properties of spray-dried powder oil. [ABSTRACT FROM AUTHOR]

Quality changes and antioxidant properties of microencapsulated kenaf ( Hibiscus cannabinus L.) seed oil (MKSO) were investigated at 6-day intervals during 24 days of storage at 65 °C. DPPH, ABTS, FRAP and BCB assays were used to determine the antioxidant activity (AOA) and their correlations were reported. Total flavonoids content (TFC) and oxidative stability in terms of evolution of thiobarbituric acid reactive substances (TBARS) were also studied. The results showed that there was a significant ( p < 0.05) effect of microencapsulation whereby AOA of MKSO showed only a 23.28 % decrease as compared to a 61.51 % decrease in the control bulk oil (KSO) when assessed by FRAP. MKSO showed significantly ( p < 0.05) lower reduction of its initial TFC as compared to KSO and total increase in TBARS of MKSO was reported to be significantly ( p < 0.05) lower than that of KSO. AOA determined by all assays were well correlated with TFC and also among themselves. Microencapsulation of kenaf seed oil was found to be effective in the stabilisation of natural antioxidants and prolonging the shelf-life. [ABSTRACT FROM AUTHOR]

Shortening derived from palm oil is widely used in baking applications. However, palm oil and the related products are reported to contain high levels of monochloropropandiol (MCPD) ester and glycidyl ester (GE). MCPD and glycidol are known as process contaminants, which are carcinogenic and genotoxic compounds, respectively. The objective was to evaluate the effects of antioxidant addition in palm olein and stearin to the content of MCPD esters and GE in baked cake. Butylated hydroxyanisole (BHA), rosemary extract and tocopherol were used to fortify the samples at 200 mg/kg and in combinations (400, 600 and 800 mg/kg rosemary or tocopherol combined with 200 mg/kg BHA). The MCPD esters and GE content, radical formation and the quality of the fats portion were analyzed. The results showed that palm olein fortified with rosemary extract yielded less 2-MCPD ester. The GE content was lower when soft stearin was fortified with rosemary. ESR spectrometry measurements showed that the antioxidants were effective to reduce radical formation. The synergistic effects of combining antioxidants controlled the contaminants formation. In conclusion, oxidation stability was comparable either in the single or combined antioxidants. Tocopherol in combination with BHA was more effective in controlling the MCPD esters and GE formation. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the effects of ultrasound-assisted extraction (UAE) condition on the yield, antioxidant activity and stability of the oil from papaya seed. The studied ultrasound variables were time, temperature, ultrasound power and solvent to sample ratio. The main goal was to optimise UAE condition providing the highest recovery of papaya seed oil with the most desirable antioxidant activity and stability. The interaction of ultrasound variables had the most and least significant effects on the antioxidant activity and stability, respectively. Ultrasound-assisted extraction provided a relatively high oil recovery (∼73%) from papaya seed. The strongest antioxidant activity was achieved by the extraction at the elevated temperature using low solvent to sample ratio. The optimum ultrasound extraction was set at the elevated temperature (62.5 °C) for 38.5 min at high ultrasound power (700 W) using medium solvent to sample ratio (∼7:1 v/w). The optimum point was practically validated. [ABSTRACT FROM AUTHOR]

Abstract: The physicochemical properties, fatty acid, tocopherol, thermal properties, 1H NMR, FTIR and profiles of non-conventional oil extracted from Citrullus colocynthis (L.) Schrad seeds were evaluated and compared with conventional sunflower seed oil. In addition, the antioxidant properties of C. colocynthis seed oil were also evaluated. The oil content of the C. colocynthis seeds was 23.16%. The main fatty acids in the oil were linoleic acid (66.73%) followed by oleic acid (14.78%), palmitic acid (9.74%), and stearic acid (7.37%). The tocopherol content was 121.85mg/100g with γ-tocopherol as the major one (95.49%). The thermogravimetric analysis showed that the oil was thermally stable up to 286.57°C, and then began to decompose in four stages namely at 377.4°C, 408.4°C, 434.9°C and 559.2°C. The present study showed that this non-conventional C. colocynthis seed oil can be used for food and non-food applications to supplement or replace some of the conventional oils. [Copyright &y& Elsevier]

Abstract: Phenolic compounds in oil palm fruit (E. guineensis) were extracted in soluble free (SFP), insoluble-bound (ISBP) and esterified (EFP) forms. The total phenolic content (TPC) of the oil palm fruit extracts was determined using the Folin–Ciocalteu method and found to range from 5.03 to 9.04g/L per g of dried weight (DW). The antioxidant activities of oil palm phenolic extracts were analysed using free radical scavenging assays and results showed that oil palm phenolic extracts contained antioxidant activities in the order of ISBP>EFP>SFP. Eight different phenolic acids were identified and quantified using a simple reversed-phase high performance liquid chromatography (HPLC) with a diode array detector (DAD) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). Ferulic, p-hydroxybenzoic and p-coumaric acid were the dominant phenolic acids found in oil palm fruit extracts and ranged from 55 to 376μg/g of DW. [Copyright &y& Elsevier]

Abstract: Response surface methodology (RSM) was applied to optimize the oven drying conditions for lycopene content (Y 1) and lipophilic antioxidant capacity (Y 2) in decanter, a by-product of the pink guava puree industry. Two-factor central composite design was employed to determine the effects of two independent variables, namely temperature (X 1: 50–80°C) and drying time (X 2: 4–6h). Lycopene content and lipophilic antioxidant capacity were measured using high-performance liquid chromatography (HPLC) and the ABTS radicals scavenging assay, respectively. A β-carotene bleaching assay was also applied to measure the antioxidant activity. Response surface plots showed that an increase in temperature and time significantly reduced the response variables. The optimum oven conditions for drying of decanter with minimum lycopene degradation were 43.8°C for 6.4h, with a predicted lycopene content of 14mg/100g and antioxidant capacity of 21μmol LE/100g. To validate the optimized model, the experimental values were compared with the predicted values to check the adequacy of the model. The experimental values were found to be in agreement with those predicted, indicating the suitability of the model for optimizing the oven drying conditions for decanter. [Copyright &y& Elsevier]

Abstract The effects of selected antioxidants on the changes of the quality properties and 3-monochloropropane-1,2-diol (3-MCPD) esters and glycidyl ester (GE) contents in refined, bleached, and deodorized (RBD) palm olein during the deep-fat frying (at 180 °C) of potato chips were studied. The frying duration was 100 min in five antioxidant systems for three consecutive days. The antioxidants used were butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), tert-butylhydroquinone (TBHQ), oleoresin rosemary and sage extract. Both the frying oil and the oil extracted from the fried potato chips were analyzed for the 3-MCPD esters and GE content, acylglycerol composition, free fatty acid (FFA) content, p -anisidine value (p-AV), and specific extinction coefficient K 232 and K 268. Generally, TBHQ and oleoresin rosemary showed significantly lower levels of 3-MCPD esters and GE. The order of effectiveness of the selected antioxidants in the frying oil and fried potato chips was BHT < BHA < sage extract < oleoresin rosemary < TBHQ. Antioxidants reduce the 3-MCPD esters and GE levels by inhibiting the formation of radical intermediates. Highlights • Effects of antioxidant on 3-MCPD esters and GEs in frying oil were studied. • Antioxidants effectively lower the formation of 3-MCPD esters and GEs. • Oleoresin rosemary showed comparable effectiveness with TBHQ. • Antioxidant inhibit the formation of intermediate ions. [ABSTRACT FROM AUTHOR]

Abstract: An investigation into the effects of ethanol concentration (0–100%, v/v), extraction time (20–120min) and extraction temperature (25–65°C) on the extraction of phenolic antioxidants from mengkudu (Morinda citrifolia) was performed using a single-factor experiment. Total phenolic content (TPC) and total flavonoid content (TFC) assays were used for determination of phenolic compounds. Antioxidant capacity was evaluated by measuring the scavenging effect on 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radicals. Experimental results showed that extraction conditions had significant effect on extraction of phenolic compounds and antioxidant capacities. The optimised conditions were 40% ethanol for 80min at 65°C, with values of 919.95mg GAE/100g DW for TPC, 472.73mg CE/100g DW for TFC, 791.71μmol TEAC/100g DW for ABTS and 1928.5μmol TEAC/100g DW for DPPH. TPC was significantly correlated with DPPH under the effects of ethanol concentration (r =0.932) and extraction time (r = −0.938). [Copyright &y& Elsevier]