Insect biorefinery: A circular economy concept for biowaste conversion to value-added products.

With rapid growing world population and increasing demand for natural resources, the production of sufficient food, feed for protein and fat sources and sustainable energy presents a food insecurity challenge globally. Insect biorefinery is a concept of using insect as a tool to convert biomass waste into energy and other beneficial products with concomitant remediation of the organic components. The exploitation of insects and its bioproducts have becoming more popular in recent years. This review article presents a summary of the current trend of insect-based industry and the potential organic wastes for insect bioconversion and biorefinery. Numerous biotechnological products obtained from insect biorefinery such as biofertilizer, animal feeds, edible foods, biopolymer, bioenzymes and biodiesel are discussed in the subsequent sections. Insect biorefinery serves as a promising sustainable approach for waste management while producing valuable bioproducts feasible to achieve circular bioeconomy.

Enhancement of protein production using synthetic brewery wastewater by Haematococcus pluvialis.

Microalgae is a sustainable protein source that has been widely applied in animal feeds, functional foods, pharmaceutical, and cosmeceutical industries. Waste products could be a potential cost-saving and nutrient-rich substrate in the cultivation of microalgae for protein production. This study aims to investigate the cultivation condition of Haematococcus pluvialis for protein synthesis using synthetic brewery wastewater (BW). H. pluvialis was cultivated in the Bold's Basal Medium (BBM) mixed with synthetic BW at different concentrations. Various cultivation conditions including brewer's spent grain hydrolysate (BSGH) concentrations, pH, and light sources were studied. The molecular weight, amino acids profile and antioxidant activity of synthesized protein were determined. Fed-batch cultivation using different percentages of fresh medium replacement for enhancing protein production was investigated. The 20% fed-batch cultivation reached 27 × 105 ± 0.42 cells/mL, and 4-fold of the protein content of 64.93 ± 5.30% of dry weight was recorded on day-13. Seven essential amino acids (lysine, threonine, histidine, phenylalanine, isoleucine, leucine, methionine) were produced in fed-batch cultivation. Red LED obtained the highest DPPH radical scavenging activity of 27.47 ± 0.98%. The findings suggested that BW is a promising substrate in the cultivation of H. pluvialis to commercially produce protein for numerous industrial applications.

Culinary Nutrition Education Improves Home Food Availability and Psychosocial Factors Related to Healthy Meal Preparation Among Children.

OBJECTIVE: To evaluate the effectiveness of a culinary nutrition education intervention on children's home food availability and psychosocial factors related to healthy meal preparation. DESIGN: Randomized-controlled trial. SETTING: Schools in Kuala Lumpur, Malaysia. PARTICIPANTS: Eighty-three school children aged 10-11 years and their parents. INTERVENTION: Twelve weeks of culinary nutrition education with 5 hands-on healthy meal preparation modules and a module with parents on home food availability (conducted every 2 weeks). MAIN OUTCOME MEASURES: Psychosocial factors (knowledge, attitude, practice, and self-efficacy) related to healthy meal preparation and home food availability (fruits, vegetables, healthful foods, and less healthful foods) assessed via children and parents, respectively, using validated questionnaires at baseline, postintervention, and 3-month follow-up. ANALYSIS: Repeated measures ANOVA. RESULTS: Intervention group had a higher (P < 0.001) mean knowledge score (mean difference, 1.2), attitude (mean difference, 2.6), practice (mean difference, 4.4) and self-efficacy (mean difference, 3.9) of healthy meal preparation as compared with control group across 3-time points. Improvements were seen in the availability of fruits (mean difference, 3.0; P < 0.001), vegetables (mean difference, 2.4; P < 0.001), healthful foods (mean difference, 1.5; P < 0.001) and less healthful foods (mean difference, -0.9; P = 0.001), favoring the intervention group. CONCLUSION AND IMPLICATIONS: Culinary nutrition education had positive impact on children's psychosocial factors and home food availability, demonstrating the potential to improve children's nutrition.

Mangosteen xanthone γ-mangostin exerts lowering blood glucose effect with potentiating insulin sensitivity through the mediation of AMPK/PPARγ.

Diabetes mellitus (DM) is concomitant with significant morbidity and mortality and its prevalence is accumulative in worldwide. The conventional antidiabetic agents are known to mitigate the symptoms of diabetes; however, they may also cause side and adverse effects. There is an imperative necessity to conduct preclinical and clinical trials for the discovery of alternative therapeutic agents that can overcome the drawbacks of current synthetic antidiabetic drugs. This study aimed to investigate the efficacy of lowering blood glucose and underlined mechanism of γ-mangostin, mangosteen (Garcinia mangostana) xanthones. The results showed γ-Mangostin had a antihyperglycemic ability in short (2 h)- and long-term (28 days) administrations to diet-induced diabetic mice. The long-term administration of γ-mangostin attenuated fasting blood glucose of diabetic mice and exhibited no hepatotoxicity and nephrotoxicity. Moreover, AMPK, PPARγ, α-amylase, and α-glucosidase were found to be the potential targets for simulating binds with γ-mangostin after molecular docking. To validate the docking results, the inhibitory potency of γ-mangostin againstα-amylase/α-glucosidase was higher than Acarbose via enzymatic assay. Interestingly, an allosteric relationship between γ-mangostin and insulin was also found in the glucose uptake of VSMC, FL83B, C2C12, and 3T3-L1 cells. Taken together, the results showed that γ-mangostin exerts anti-hyperglycemic activity through promoting glucose uptake and reducing saccharide digestion by inhibition of α-amylase/α-glucosidase with insulin sensitization, suggesting that γ-mangostin could be a new clue for drug discovery and development to treat diabetes.

Evaluation of Aqueous Biphasic Electrophoresis System Based on Halide-Free Ionic Liquids for Direct Recovery of Keratinase.

Aqueous biphasic electrophoresis system (ABES) incorporates electric fields into the biphasic system to separate the target biomolecules from crude feedstock. Ionic liquid (IL) is regarded as an excellent candidate as the phase-forming components for ABES because of the great electrical conductivity, which can promote the electromigration of biomolecules in ABES, and thereby enhances the separation efficiency of the target biomolecules from crude feedstock. The application of electric fields to the conventional biphasic system expedites the phase settling time of the biphasic system, which eases the subsequent scaling-up steps and reduces the overall processing time of the recovery process. Alkyl sulphate-based IL is a green and economical halide-free surfactant when compared to the other halide-containing IL. The feasibility of halide-free IL-based ABES to recover Kytococcus sedentarius TWHK01 keratinase was studied. Optimum partition coefficient (Ke = 7.53 ± 0.35) and yield (YT = 80.36% ± 0.71) were recorded with IL-ABES comprised of 15.0% (w/w) [EMIM][ESO4], 20.0% (w/w) sodium carbonate and 15% (w/w) crude feedstock. Selectivity (S) of 5.75 ± 0.27 was obtained with the IL-ABES operated at operation time of 5 min with 10 V voltage supplied. Halide-free IL is proven to be a potential phase-forming component of IL-ABES for large-scale recovery of keratinase.

Characterization of alcohol/salt aqueous two-phase system for optimal separation of gallic acids.

Gallic acid (GA) is a hydrophilic polyphenol which is noteworthy for strong antioxidant capacity. The drawbacks of conventional extraction approaches such as time-consuming and high processing cost are often viewed as a hurdle to extract GA from plant sources in industrial scale. Aqueous two-phase system (ATPS) is a separation approach which can be employed as an alternative to the conventional approaches. The partition behaviour of GA in an alcohol/salt ATPS was investigated in this study to aid the development of industrial scale ATPS to extract GA from natural sources. The separation of GA was characterized by determining the types of alcohol and salt, phase composition, sample load, pH of the system and addition of adjuvants applied in the alcohol/salt ATPS construction. The hydrophilic GA was targeted to the salt-rich phase of the alcohol/salt ATPS with a partition coefficient (KGA) of 25.00 ± 0.00. The optimum condition of ATPS for the maximum partition of GA was achieved in ATPS comprised of 24% (w/w) 1-propanol and 22% (w/w) phosphate salt at pH 8 with 5% (w/w) of 1 mg/mL sample loading and 2% (w/w) NaCl addition. The findings suggest that ATPS can be applied for separation of GA from various natural sources.

Surfactant as an Additive for the Recovery of Potent Antioxidants from Garcinia mangostana Pericarps Using a Polymer/Salt Aqueous Biphasic System.

Garcinia mangostana pericarp is a good source of natural antioxidants with numerous functional properties. The conventional approaches for the recovery of antioxidants from Garcinia mangostana pericarp require long processing time and high temperature, which may cause degradation or loss of bioactivity of antioxidants, and often result in low recovery efficiency. In this study, the extraction of antioxidants from Garcinia mangostana pericarp was investigated using a polyethylene glycol (PEG)/citrate aqueous biphasic system (ABS) with the addition of surfactants. The optimum condition for the recovery of antioxidants was achieved in PEG 1000/citrate ABS of pH 8 with tie-line length (TLL) of 48.3% (w/w), volume ratio (VR) of 1.6, 0.2% (w/w) sample loading and addition of 1.0% (w/w) Tween 85. The antioxidants were recovered in the PEG-rich top phase with a high K value of 18.23 ± 0.33 and a recovery yield of 92.01% ± 0.09. The findings suggested that the addition of surfactants to polymer/salt ABS can enhance the recovery of antioxidants from Garcinia mangostana pericarps by conserving the antioxidative properties.

Recent advances on the sustainable approaches for conversion and reutilization of food wastes to valuable bioproducts.

The increasing amounts of food wastage and accumulation generated per annum due to the growing human population worldwide often associated with environmental pollution issues and scarcity of natural resources. In view of this, science community has worked towards in finding sustainable approaches to replace the common practices for food waste management. The agricultural and food processing wastes rich in nutrients are often the attractive substrates for the bioconversion for valuable bioproducts such as industrial enzymes, biofuel and bioactive compounds. The sustainable approaches on the re-utilization of food wastes as the industrial substrates for production of valuable bioproducts has meet the goals of circular bioeconomy, results in the diversify applications and increasing market demands for the bioproducts. This review discusses the current practice and recent advances on reutilization of food waste for bioconversion of valuable bioproducts from agricultural and food processing wastes.

Efficiency of Ionic Liquids-Based Aqueous Two-phase Electrophoresis for Partition of Cytochrome c.

Cytochrome c is a small water-soluble protein that is abundantly found in the mitochondrial intermembrane space of microorganism, plants and mammalians. Ionic liquids (ILs)-based aqueous two-phase electrophoresis system (ATPES) was introduced in this study to investigate the partition efficiency of cytochrome c to facilitate subsequent development of two-phase electrophoresis for the separation of cytochrome c from microbial fermentation. The 1-Hexyl-3-methylimidazolium bromide, (C6mim)Br and potassium citrate salt were selected as the phase-forming components. Effects of phase composition; position of electrodes; pH and addition of neutral salt on the partition efficiency of cytochrome c in the ATPES were evaluated. Highest partition coefficient (K = 179.12 ± 0.82) and yield of cytochrome c in top phase (YT = 99.63% ± 0.00) were recorded with IL/salt ATPES composed of 30% (w/w) (C6mim)Br and 20% (w/w) potassium citrate salt of pH 7 and 3.0% (w/w) NaCl addition with anode at the bottom phase and cathode at the top phase. The SDS-PAGE profile revealed that cytochrome c with a molecular weight of 12 kDa was preferably partitioned to the IL-rich top phase. Present findings suggested that the single-step ATPES is a potential separation approach for the recovery of cytochrome c from microbial fermentation. Graphical Abstract.

Partition efficiency of cytochrome c with alcohol/salt aqueous biphasic flotation system.

Aqueous biphasic flotation (ABF) integrates aqueous biphasic system (ABS) and solvent sublation for recovery of target biomolecules. The feasibility of the alcohol/salt ABF for exclusive partition of cytochrome c to one specific phase of the system was investigated. Aliphatic alcohols of different carbon chain length (ethanol, 1-propanol and 2-propanol) and salts (sulfate, phosphate and citrate) were used for the phase formation. The effects of phase composition, concentration of sample loading, pH, flotation time and flow rate of the system on the partition efficiency of cytochrome c were determined. Cytochrome c was exclusively partitioned to the alcohol-rich top phase of the ABF of 18% (w/w) ethanol and 26% (w/w) ammonium sulfate with pH 6 and 20% (w/w) of sample loading. Highest partition coefficient (K) of 6.85 ± 0.21 and yield (YT) of 99.40% ± 0.02 were obtained with optimum flotation rate of 10 mL/min and flow rate of 10 min.

Risk factors for low birth weight among rural and urban Malaysian women.

BACKGROUND: Low birth weight prevalence in Malaysia remains high. Socioeconomic background may lead to differences in physical activity and maternal nutritional status, which may play an important role in birth outcomes. METHODS: This prospective cross-sectional study aimed to identify rural-urban differences in risk factors for low birth weight among women in Malaysia. Pregnant women at ≥20 weeks of gestation in urban and rural Malaysia (n = 437) completed questionnaires on sociodemographic characteristics and physical activity. Weight and middle-upper arm circumference were measured. Infant birth outcomes were extracted from medical records. RESULTS: The overall prevalence of low birth weight infants was 6.38%. Rural women had more low birth weight infants than urban women (9.8% vs 2.0%, p = 0.03). Findings showed rural women were less sedentary (p = 0.003) and participated in more household/caregiving activities (p = 0.036), sports activities (p = 0.01) and less occupational activity (p < 0.001) than urban women. Logistic regression revealed that older age (OR = 1.395, 95% Cl = 1.053 to 1.846), low parity (OR = 0.256, 95% Cl = 0.088-0.747) and low middle-upper arm circumference (OR = 0.738, 95% Cl = 0.552 to 0.987) increased the risk of low birth weight infants in rural, but not in urban women. CONCLUSIONS: We observed differences in risk factors for low birth weight between urban and rural pregnant women. Age, malnutrition and low parity were risk factors for low birth weight among rural pregnant women. Our findings suggest that rural pregnant women with low nutritional status should be encouraged to monitor their middle-upper arm circumference consistently throughout pregnancy. Improving nutritional status in rural pregnant women may reduce the risk of low birth weight infants in this population.

Nutrients for Prevention of Macular Degeneration and Eye-Related Diseases.

The risk of macular degeneration can be reduced through the consumption of antioxidant-rich foods, supplements, and nutraceutical formulas. This review focuses on the antioxidants, vitamins, and minerals that have been reported for reducing the risk of macular degeneration and other eye-related diseases. Antioxidants including anthocyanins, carotenoids, flavonoids, and vitamins have been shown to reduce the risk of eye-related diseases. Anthocyanins extracted from berries are powerful antioxidants. Cyanidin, delphinidin, malvidin, pelargonidin, peonidin, and petunidin are anthocyanin aglycones detected in berries, currants, and other colored fruits and vegetables. ß-Carotene, as well as xanthophyll lutein and zeaxanthin, have been reported to reduce the risk of macular degeneration. Flavonoids from plants help in the prevention of eye-related diseases through anti-inflammatory mechanisms. A combination of these antioxidants, vitamins, and minerals possess a synergistic effect on the prevention or risk reduction of macular degeneration. Formulas have been developed as dietary supplements to cater to the high demand from consumers and patients with eye problems. Many of the formulated dietary supplements that are sold in the market have been clinically proven for their efficacy to treat eye diseases. Although the bioactivities in the supplement capsules or tablets have been scientifically established for reducing risks of several diseases, which include macular degeneration and other eye-related diseases, knowledge on the right dosage, efficacy, and bioavailability of antioxidants, vitamins, and minerals is important for consumers. The information may help them make the best decision in choosing the right dietary supplements and nutraceuticals following the evidence-based recommended dosages and reference intakes for improving general health and preventing eye-related diseases. This review covers the potential causal factors involved in eye diseases, clinically proven treatments, and controversial findings on the antioxidants in the prevention of macular degeneration. Future studies should consider multiethnic and multicenter trials for eliminating potential bias in research.

Psychological Factors and Cardiovascular Disease Risk Factors as Mediators of the Relationship between Overweight/Obesity and Cognitive Function among School Children in Kuala Lumpur, Malaysia.

BACKGROUND: Recent research suggests that a negative relationship exists between adiposity and cognitive function in children. However, limited information is known on how they are related. This study aimed to examine the mediators of the relationship between overweight/obesity and cognitive function among school children in Kuala Lumpur, Malaysia. METHODS: This is a cross-sectional comparison study whereby 225 overweight/obese children matched for age, sex, and ethnicity with 225 normal weight children participated in this study. Body image dissatisfaction, disordered eating, and depressive symptoms were assessed through a self-administered questionnaire. Blood pressure was measured, whereas blood was drawn to determine insulin, high-sensitivity C-reactive protein (hs-CRP), glucose, and lipid profiles. Homeostasis model assessment-estimated insulin resistance (HOMA-IR) was calculated using glucose and insulin levels. Wechsler's Intelligence Scale for Children-Fourth Edition (WISC-IV) was used to assess cognitive function in children. Ordinary least square regression analysis was conducted to determine the direct and indirect relationships between weight status and cognitive function. RESULTS: A negative relationship was found between overweight/obesity with cognitive function. Overweight/obese children were on average 4.075 units lower in cognitive function scores compared to normal weight children. Such difference was found through mediators, such as body image dissatisfaction, disordered eating, depression, systolic blood pressure, triglycerides, HOMA-IR, and hs-CRP, contributing 22.2% of the variances in cognitive function in children. CONCLUSION: Results highlight the important mediators of the relationship between overweight/obesity and cognitive function. Consequently, future interventions should target to improve psychological well-being and reduce cardiovascular disease risk for the prevention of poorer cognitive performance in overweight/obese children.

Direct recovery of mangostins from Garcinia mangostana pericarps using cellulase-assisted aqueous micellar biphasic system with recyclable surfactant.

The α- and γ-mangostins from Garcinia mangostana pericarps (GMP) exhibit antioxidant, anti-bacterial, anti-inflammatory and anti-tumor properties. The extraction yields α- and γ-mangostins are often limited by the presence of the GMP cell walls. Therefore, the extraction and recovery of mangostins from GMP with an Aspergillus niger cellulase-assisted aqueous micellar biphasic system (CA-AMBS) was developed for enhanced yield of mangostins. Effects of the concentration of cellulase, the incubation time and the temperature of the system on the recovery of mangostins were investigated. The optimum condition for the recovery of α- and γ-mangostins was obtained with the addition of 0.5% (w/w) cellulase incubated at 40°C for 2 h. High log partition coefficients of α-mangostins (log Kα 4.79 ± 0.02) and γ-mangostins (log Kγ 4.02 ± 0.02) were achieved. High yields of α-mangostins (73.4%) and γ-mangostins (14.0%) were obtained from the micelle-rich bottom phase with final concentrations of 3.67 mg/mL and 0.70 mg/mL, respectively. The back-extraction of mangostins was performed with the addition of 30% (w/w) of isopropanol and 0.05 M of KCl at pH 9 to the bottom phase of the CA-AMBS. The yields of the α- and γ-mangostins from GMP were considerably enhanced with the CA-AMBS and the direct recovery of mangostins was demonstrated without additional downstream processing steps.

Socioeconomic Status and Glycemic Index Among Punjabis in Kuala Lumpur, Malaysia: Possible Association with Metabolic Syndrome.

There are only limited reports on Punjabi's health status in Malaysia. This cross-sectional study assessed the prevalence of metabolic syndrome (Mets) and its risk factors among 277 subjects recruited from the Malaysian Punjabi community. Overall prevalence of Mets was 43%, but 61% among females. Subjects classified with Mets had significantly (p < 0.05) higher body mass index, visceral fat and percentage of body fat. Daily carbohydrate and glycemic index (GI) were also higher among Mets subjects (p < 0.05). Logistics regression analysis showed that primary level of education (OR 5.57, CI 1.29-23.97, p = 0.021) was a factor associated with Mets, followed by middle household income (OR 2.30, CI 1.01-5.20, p = 0.046), GI (OR 1.03, CI 1.00-1.06, p = 0.026), and age (OR 1.03, CI 1.00-1.05, p = 0.023). Mets shows high prevalence among the studied Punjabi population, prompting the consideration of adequate preventive measures, primarily among lower socioeconomic groups.

Direct recovery of Bacillus subtilis xylanase from fermentation broth with an alcohol/salt aqueous biphasic system.

Xylanase enzyme degrades linear polysaccharide ß-1,4 xylan and the hemicellulose of the plant cell wall. There is a growing demand in finding a cost-effective alternative for industrial scale production of xylanase with high purity for pharmaceutical applications. In this study, an alcohol/salt aqueous biphasic system (ABS) was adopted to recover xylanase from the Bacillus subtilis fermentation broth. The effects of several ABS parameters such as types and concentrations of alcohols and salts (i.e., sulphate, phosphate, and citrate), amount of crude loading and pH of the system on the recovery of xylanase were investigated. Partition coefficient of xylanase (KE), selectivity (S) and yield (YT) of xylanase in top phase of the ABS were measured. Highest KE (6.58 ± 0.05) and selectivity (4.84 ± 0.33) were recorded in an ABS of pH 8 composed of 26% (w/w) 1-propanol, 18% (w/w) ammonium sulphate. High YT of 71.88% ± 0.15 and a purification fold (PFT) of 5.74 ± 0.33 were recorded with this optimum recovery of xylanase using alcohol/salt ABS. The purity of xylanase recovered was then qualitatively verified with sodium dodecyl sulphate (SDS) gel electrophoresis. The SDS profile revealed the purified xylanase was successfully obtained in the top phase of the one-step 1-propanol/sulphate ABS with a distinct single band.

Influence of different extraction conditions on antioxidant properties of soursop peel.

BACKGROUND: Soursop is a healthy fruit. Peels form about 20% of the soursop fruit and are usually discarded as waste product. With a view to utilizing soursop peel as a source of valuable compounds, this study aimed to investigate the influence of different extraction conditions on total phenolic content (TPC) and antioxidant capacity (AC) of soursop (Annona muricata L.) peel. METHODS: Different ethanol concentrations (20-100%, v/v), extraction temperatures (25- 60°C), and extraction time (1-5 h) were tested. Extracts were prepared on the basis of the best optimal extraction conditions (20% ethanol, 40°C the extraction temperature, and 4 h of extraction time), an optimal TPC and AC was determined for the soursop peel using DPPH, ABTS, FRAP and ß-carotene bleaching (BCB) assays. The different extraction conditions tested at best optimum conditions have significantly affected the TPC and AC of the soursop peel. RESULTS: Soursop peel extract extracted in the best optimal extraction conditions had moderate levels of TPC (52.2 µg GAE/ml), and FRAP value (58.9 µg TE/ml extract). The extract demonstrated high BCB inhibitory activity (80.08%). The EC50 values of the extract were high, 1179.96 and 145.12 µg/ml, as assessed using DPPH and ABTS assays, respectively. The TPC was positively and highly correlated with the AC of soursop peel assessed by ABTS, FRAP, and BCB assay, but it was moderately correlated with DPPH radical scavenging activity. A moderate correlation of TPC with DPPH suggested that polyphenols in the extracts were partially responsible for the AC. CONCLUSIONS: By-products of soursop such as its peel could be an inexpensive source of good natural antioxidants with nutraceutical potential in the functional food industry.

Optimization of extraction parameters on the antioxidant properties of banana waste.

BACKGROUND: Banana is grown worldwide and consumed as ripe fruit or used for culinary purposes. Peels form about 18-33% of the whole fruit and are discarded as a waste product. With a view to exploiting banana peel as a source of valuable compounds, this study was undertaken to evaluate the effect of different extraction parameters on the antioxidant activities of the industrial by-product of banana waste (peel). METHODS: Influence of different extraction parameters such as types of solvent, percentages of solvent, and extraction times on total phenolic content (TPC) and antioxidant activity of mature and green peels of Pisang Abu (PA), Pisang Berangan (PB), and Pisang Mas (PM) were investigated. The best extraction parameters were initially selected based on different percentages of ethanol (0-100% v/v), extraction time (1-5 hr), and extraction temperature (25-60°C) for extraction of antioxidants in the banana peels. Total phenolic content (TPC) was evaluated using Folin-Ciocalteu reagent assay while antioxidant activities (AA) of banana peel were accessed by DPPH, ABTS, and ß-carotene bleaching (BCB) assays at optimum extraction conditions. RESULTS: Based on different extraction solvents and percentages of solvents used, 70% and 90% of acetone had yielded the highest TPC for the mature and green PA peels, respectively; 90% of ethanol and methanol has yielded the highest TPC for the mature and green PB peels, respectively; while 90% ethanol for the mature and green PM peels. Similar extraction conditions were found for the antioxidant activities for the banana peel assessed using DPPH assay except for green PB peel, which 70% methanol had contributed to the highest AA. Highest TPC and AA were obtained by applying 4, 1, and 2 hrs extraction for the peels of PA, PB and PM, respectively. The best extraction conditions were also used for determination of AAs using ABTS and ß-carotene bleaching assays. Therefore, the best extraction conditions used have given the highest TPC and AAs. CONCLUSIONS: By-products of banana (peel) can be considered as a potential source of antioxidants in food and pharmaceutical industry.

Antioxidant effcacy of unripe banana (Musa acuminata Colla) peel extracts in sunflower oil during accelerated storage.

BACKGROUND: Sunflower oil is prone to oxidation during storage time, leading to production of toxic compounds that might affect human health. Synthetic antioxidants are used to prevent lipid oxidation. Spreading interest in the replacement of synthetic food antioxidants by natural ones has fostered research on fruit and vegetables for new antioxidants. METHODS: In this study, the efficacy of unripe banana peel extracts (100, 200 and 300 ppm)  in stabilizing sunflower oil was tested under accelerated storage (65°C) for a period of 24 days. BHA and α-tocopherol served as comparative standards besides the control. Established parameters such as peroxide value (PV), iodine value (IV), p-anisidine value (p-AnV), total oxidation value (TOTOX), thiobarbituric acid reactive substances (TBARS) and free fatty acid (FFA) content were used to assess the extent of oil deterioration. RESULTS: After 24 days storage at 65°C, sunflower oil containing 200 and 300 ppm extract of unripe banana peel showed significantly lower PV and TOTOX compared to BHA and α-tocopherol. TBARS, p-AnV and FFA values of sunflower oil containing 200 and 300 ppm of unripe banana peel extract exhibited comparable inhibitory effects with BHA. Unripe banana peel extract at 200 and 300 ppm demonstrated inhibitory effect against both primary and secondary oxidation up to 24 days under accelerated storage conditions. CONCLUSIONS: Unripe banana peel extract may be used as a potential source of natural antioxidants in the application of food industry to suppress lipid oxidation.

Assessment of extraction parameters on antioxidant capacity, polyphenol content, epigallocatechin gallate (EGCG), epicatechin gallate (ECG) and iriflophenone 3-C-ß-glucoside of agarwood (Aquilaria crassna) young leaves.

The effects of ethanol concentration (0%-100%, v/v), solid-to-solvent ratio (1:10-1:60, w/v) and extraction time (30-180 min) on the extraction of polyphenols from agarwood (Aquilaria crassna) were examined. Total phenolic content (TPC), total flavonoid content (TFC) and total flavanol (TF) assays and HPLC-DAD were used for the determination and quantification of polyphenols, flavanol gallates (epigallocatechin gallate--EGCG and epicatechin gallate--ECG) and a benzophenone (iriflophenone 3-C-ß-glucoside) from the crude polyphenol extract (CPE) of A. crassna. 2,2'-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was used to evaluate the antioxidant capacity of the CPE. Experimental results concluded that ethanol concentration and solid-to-solvent ratio had significant effects (p<0.05) on the yields of polyphenol and antioxidant capacity. Extraction time had an insignificant influence on the recovery of EGCG, ECG and iriflophenone 3-C-ß-glucoside, as well as radical scavenging capacity from the CPE. The extraction parameters that exhibited maximum yields were 40% (v/v) ethanol, 1:60 (w/v) for 30 min where the TPC, TFC, TF, DPPH, EGCG, ECG and iriflophenone 3-C-ß-glucoside levels achieved were 183.5 mg GAE/g DW, 249.0 mg QE/g DW, 4.9 mg CE/g DW, 93.7%, 29.1 mg EGCG/g DW, 44.3 mg ECG/g DW and 39.9 mg iriflophenone 3-C-ß-glucoside/g DW respectively. The IC50 of the CPE was 24.6 mg/L.