Pineapple is one of the most important commercial fruit crops served in fresh-cut form which is convenientfor the consumers. However, fresh-cut pineapple induces the activity of phenolic compounds which triggers the generation of brown or dark pigments. Browning incidence (BI) directly influences the fruit’s acceptability and marketability. Therefore, different exposure times (5mins, 10mins, 15mins and 20mins)and typesof LED lights (white, red and blue) were applied on fresh-cut pineapple stored at 5oC storage for twelve days to reduce BI. A significant interaction between the two factors was recorded in lightness coefficient, chroma, total phenolic and ascorbic acid (AA)contents. Regardless of exposure times, all types of LED lights, mainly the blue light, succeeded in delaying BI in fresh-cut pineapple. In conclusion, blue light had a tendency todelay BI andmaintaintheother postharvest quality attributes of fresh-cut pineapple.
This study was done to determine the effects of different thermal drying methods (sun drying, microwave drying and hot air oven drying) on the total phenolic content (TPC), total anthocyanin content and the antioxidant properties of Vitex negundo (VN) tea. Significant decline (P < 0.05) in antioxidant properties of hot air oven drying shows that this method is not the best method to preserve antioxidant compounds in VN tea. As a conclusion, microwave drying has been found to be a good method for maintain the TPC, anthocyanin content and AEAC in dried sample of VN tea.
The emerging studies suggest antioxidant may represent an important role in defence against certain diseases outlined the necessity of determining their contents in tamarillo (Cyphomandra betacea), cherry tomato (Solanum lycopersicum var. cerasiforme), and tomato (Lycopersicon esculentum). This study aims to determine the antioxidant capacity, total phenolic content and total flavonoid content in tamarillo, yellow cherry tomato, red cherry tomato, and tomato in 70% ethanol and water extracts. The ethanol extract showed the highest scavenging activity, ferric reducing activity, phenolic and flavonoid contents, whereas, the water extract showed higher value for antioxidant activity in β-Carotene bleaching assay. Tamarillo showed the highest antioxidant activity (22.92 ± 3.60%, 28.89 ± 3.85%), scavenging activity (44.25 ± 0.82 μg/ml, 47.38 ± 1.11 μg/ml), ferric reducing activity (12.17 ± 0.53 μM Fe (II)/g, 3.72 ± 0.20 μM Fe (II)/g), phenolic content (7.63 ± 0.37 mg GAE/g edible portion, 1.83 ± 0.50 mg GAE/g edible portion) and flavonoid content (6.44 ± 0.16 mg CE/g edible portion, 2.22 ± 0.31 mg CE/g edible portion) in ethanol and water extracts respectively. For ethanol extracts a positive correlations existed (0.66 ≤ r ≥ 0.97) between ferric reducing activity, antioxidant activity, phenolic content and flavonoid content. While, in water extract correlation test revealed a positive correlations between antioxidant activity, ferric reducing activity and phenolic content (0.645 ≤ r ≥ 0.706) and between antioxidant activity and flavonoid content (r = 0.820). In conclusion, tamarillo exhibits the highest antioxidant capacity, phenolic content and also flavonoid content.
Cocoa pod borer (Conopomorpha cramerella (Snellen)) is the main fatal pest that destroys cocoa plantations in South East Asia, mainly in Indonesia and Malaysia. Infested cocoa beans stick to each other, the pulp become hard and normal fermentation process to produce flavour precursors cannot be done. This research aimed to utilize the infested cocoa beans as a source of phenolic compounds. Extraction of phenolic compounds was carried out for three infestation levels regarded as low, medium and heavy. Parameters of study were bean size, shell content, fat content, total polyphenol and antioxidant activity. Results of the study showed that the increase in cocoa pod borer infestation significantly decreased cocoa bean size, fat content and total polyphenol; but shell content was increased. Antioxidant activity of the extracted polyphenol was not significantly affected by the infestation. The results clearly indicate that cocoa beans infested by cocoa pod borer can potentially to be used as a source of phenolic compounds for natural antioxidant uses.
The aim of this work was to investigate the antioxidant and antimicrobial of Phyllanthus amarus, Phyllanthus niruri and Phyllanthus urinaria. P. niruri was found to possess the highest antioxidant activity, the activity decreased in the order P. niruri > P. amarus > P. urinaria for water extract. However, the activity decreased in the order P. niruri > P. urinaria > P. amarus for methanol extract. The result correlation between the antioxidant activity and total phenolic content revealed a positive correlation of 0.954 < r 2 < 1.000 for both water and methanol extract. Methanol extract showed higher total phenolic content and antioxidant activity as compared with water extract. Lowest Minimum Inhibitory Concentration (MIC) value for water extract against the selected microorganism was >2.5 mg/mL meanwhile, for methanol extract was 2.5 mg/mL and >0.625 mg/mL were the value for water and methanol extract. Methanol extract showed better inhibition potential than water extract
Quercus infectoria gall, which is known as manjakani in Malaysia, was traditionally used in treating diseases. The bioactive compounds from the galls can be extracted using various extraction methods. In this study, supercritical carbon dioxide (SC-CO2) extraction was used to study the effects of CO2 flow rate on the yield, total phenolic content and antioxidant activity of Q. infectoria extract by fixing the pressure and temperature at the highest density (P: 30 MPa, T: 40°C). The results were compared with those acquired from the Soxhlet extraction method. The results showed that the Soxhlet extraction had a higher percentage of extraction yield than SC-CO2 extraction. The selectivity of Q. infectoria extracts using SC-CO2 extraction was better than the Soxhlet extraction method. Meanwhile, the extraction efficiency using the SC-CO2 extraction ranged from 46% to 53%. The SC-CO2 extraction also yielded higher total phenolic content than using the Soxhlet extraction method when 2 mL/min of CO2 flow rate was applied (203.53 mg GA/g sample). This study also revealed that the extracts from the SC-CO2 extraction showed a better radical scavenging activity compared to the Soxhlet extraction when analysed using DPPH (2,2-diphenyl-1-picryl hydrazyl) radical scavenging activity assays.radical scavenging activity compared to the Soxhlet extraction when analysed using DPPH (2,2-diphenyl-1-picryl hydrazyl) radical scavenging activity assays.
The adsorption of phenol, from aqueous solutions on activated carbon from waste tyres, was studied in a batch system at different initial concentrations (100-500mg/L) at 30°C for 48 hours. The activated carbon was prepared using the two-step physiochemical activation, with potassium hydroxide (KOH) at ratio KOH/char = 5. The carbonization process was done at 800°C for 1 hour with nitrogen flow rate 150ml/min, followed by the activation with the carbon dioxide flow rate 150ml/min at 800°C for 2 hours. The adsorption isotherms were determined by shaking 0.1g of activated carbon with 100ml phenol solutions. The initial and final concentrations of phenol in aqueous solution were analyzed using the UV-Visible Spectrophotometer (Shimadzu, UV-1601) at a wavelength of 270nm. Experimental isotherm data were analyzed using the Langmuir and Freundlich isotherm models.The equilibrium data for phenol adsorption could fit both isotherm models well with the R2 value of 0.9774 and 0.9895, respectively. The maximum adsorption capacity of the adsorbent obtained from the Langmuir model was up to 156.25 mg/g
Learning environment in the universities plays an important role in producing highly competent graduates especially in nursing profession. Thus, the most important as-pects are the teaching activities and as well as student – teacher interaction in daily environment in the university. To investigate the International Islamic University Malay-
sia (IIUM) nursing students experience towards their teachers and to identify the rela-tionship between teaching and students learning perception in their learning environ-ment. This study used quantitative method and utilized two out of five subscales in Dundee Ready Educational Environment Measurement (DREEM). The subscales used
were students’ perception of learning (SPoL) , students’ perception of teacher (SPoT)
and total items in these both subscales are 12 and 11 items, respectively. The ques-tionnaire results revealed that IIUM nursing students scored 28.54/48.00 in (SPoL) and
28.13/44.00 in (SPoT). Both findings showed the IIUM nursing students’ experience their teachers and the learning environment are moving in towards positive directions. The regression finding was 51% of the total variation in students’ perception of teacher score was explained by students’ perception of learning. Although the overall sub-scales (SPoL) score in the current study falls in the category of a more positive per-ception, 2 out of 12 items were poorly scored by the IIUM nursing students. The re-searcher strongly agrees that listening to the expression of students is an important consideration for an educational institution. The overall mean score for (SPoT) showed that the students perceived their teachers as moving in the right direction. In this pre-sent IIUM study, one item showed a mean score of less then 2.00. As a result, these two subscales most probably should reflect the same outcome such as in their aca-demic performance and experience greatly during their student life on campus. The arising issues from this DREEM study at IIUM embrace the need for the creation of supportive environment as well as designing and implementing interventions to remedy unsatisfactorily elements of the learning environment for more effective and successful teaching and learning to be realised.
The widespread distribution of persistent organic pollutants (POPs) in landfill leachate is problematic due to their acute toxicity, carcinogenicity and genotoxicity effects, which could be detrimental to public health and ecological systems. The objective of this study was to evaluate the effective removal of POPs - namely, p-tert-Butylphenol and Pyridine, 3-(1-methyl-2-pyrrolidinyl)-, (S)- - from landfill leachate using locust bean gum (LBG), and in comparison with commonly used alum. The response surface methodology coupled with a Box-Behnken design was employed to optimize the operating factors for optimal POPs removal. A quadratic polynomial model was fitted into the data with the R2 values of 0.97 and 0.96 for the removal of p-tert-Butylphenol and Pyridine, 3-(1-methyl-2-pyrrolidinyl), (S)-, respectively. The physicochemical characteristics of the flocs produced by LBG and alum were evaluated with Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM). The infrared spectra of LBG-treated floc were identical with LBG powder, but there was some variation in the peaks of the functional groups, signifying the chemical interactions between flocculants and pollutant particles resulting from POPs removal. The results showed that p-tert-Butylphenol and Pyridine, 3-(1-methyl-2-pyrrolidinyl)-, (S)- obtained 96% and 100% removal using 500 mg/L of LBG at pH 4. pH have a significant effect on POPs removal in leachate. It is estimated that treating one million gallons of leachate using alum (at 1 g/L dosage) would cost US$39, and using LBG (at 500 mg/L dosage) would cost US$2. LBG is eco-friendly, biodegradable and non-toxic and, hence, strongly recommended as an alternative to inorganic coagulants for the treatment of POPs in landfill leachate.
Cruciferous vegetables belong to the mustard family of plants such as Brussels sprouts, kale, broccoli, cabbage and cauliflower. They are well known for their cancer prevention properties which are due to high content of bioactive compounds, isothiocyanates (ITCs). This study was aimed to investigate nitrosation inhibition ability of the cruciferous vegetables commonly consumed with meat products namely, broccoli, cauliflower and cabbage. Aqueous extracts of fresh and steamed (2 and 4 min) vegetables were subjected to determination of antioxidant capacity (DPPH and FRAP assay) and chemical composition i.e. total phenolic and isothiocyanate (ITC) content. It was found that TPC, DPPH and FRAP values of raw vegetables were different in each vegetable and ranged from 17.12-38.91 mg GAE/100 ml, 44.09-63.31% and 1.36-6.81 mg TE/100 ml, respectively. Among three types of cruciferous vegetable, broccoli had the highest PEITC content being 0.21 mmol/100 g compared to cauliflower (0.15 mmol/100 g) and cabbage (0.06 mmol/100 g). Moreover, it was found that steaming process significantly enhanced antioxidant activity, TPC as well as PEITC content in a timedependent manner up to 4 min (p
This study utilized the incorporation of nanoparticle filler into an epoxy system to study the effect of different nanosized
montmorillonite (MMT) fillers on the thermal stability and mechanical properties of epoxy. The sample was prepared
using diglycidyl ether of bisphenol A (DGEBA) with different surface treatments of montmorillonite filler by mechanical
stirring. The results of thermal stability and mechanical properties of epoxy/clay system obtained from thermal gravimetric
analyzer (TGA), universal testing machine (UTM) and scanning electron microscopy (SEM) were discussed. With the same
amount of filler introduced into the system, different thermal stability of epoxy composite can be observed. Bentonite,
which contained other contaminant components, can downgrade the enhanced properties of the filler.
This study was designed to determine the physicochemical, antioxidant and microbial properties of fresh sugarcane juice
with calamansi juice addition. The sugarcane that was used in the experiments was the black cane variety (Saccharum
officinarum). Sugarcane pressed with and without their peel was juiced and added with calamansi juice before analysis
was carried out. Standard method was used to analyse physicochemical properties such as pH, total soluble solids,
acidity and colour of sugarcane juice. Total phenolic content (TPC), DPPH and FRAP assay were conducted for antioxidant
properties. Total plate count and yeast and mould count were carried out for the microbiological analyses. Two way
analysis of variance (ANOVA) shows significant (p<0.05) difference on colour of sugarcane juiced after extraction with and
without peel. There were no significant (p>0.05) difference shown for pH, acidity and total soluble solids of sugarcane
juice pressed with and without peel. Sugarcane juice pressed with peel produced higher antioxidant value compared
to sugarcane pressed without peel. However, sugarcane juice pressed without peeled showed a lower microbial count
compared to sugarcane juice pressed with peel. The addition of calamansi juice proved to have significant (p<0.05)
effect on colour, antioxidant and microbial count of the sugarcane juices.
Heat explosions are sometimes observed during the synthesis of phenol formaldehyde (PF) resin. This scenario can be attributed to the high latent heat that was released and not dissipated leading to the occurrence of a runaway reaction. The synthesis temperature and time played important roles in controlling the heat release, hence preventing the resin from hardening during the synthesis process. This study aims to assess the rheological and viscoelasticity behaviors of the PF resin prepared using paraformaldehyde. The prepared PF resin was designed for laminate applications. The rheological behavior of the PF resin was assessed based on the different molar ratios of phenol to paraformaldehyde (P:F) mixed in the formulation. The molar ratios were set at 1.00:1.25, 1.00:1.50 and 1.00:1.75 of P to F, respectively. The rheological study was focused at specific synthesis temperatures, namely 40, 60, 80 and 100 °C. The synthesis time was observed for 240 min; changes in physical structure and viscosity of the PF resins were noted. It was observed that the viscosity values of the PF resins prepared were directly proportional to the synthesis temperature and the formaldehyde content. The PF resin also exhibited shear thickening behavior for all samples synthesized at 60 °C and above. For all PF resin samples synthesized at 60 °C and above, their viscoelasticity results indicated that the storage modulus (G'), loss modulus(G″) and tan δ are proportionally dependent on both the synthesis temperature and the formaldehyde content. Heat explosions were observed during the synthesis of PF resin at the synthesis temperature of 100 °C. This scenario can lead to possible runaway reaction which can also compromise the safety of the operators.
Antioxidant properties of both fresh and convection oven-dried guavas (Psidium guajava L.) were determined. Guava slices of 1.0 cm wide, 3.0 cm long and 0.5cm thick (20 g) were subjected to convection drying at 40°C for 9, 12 and 14 hours, respectively, and their water activity, total phenolic content (TPC) and antioxidant activities were measured. Guavas that had been subjected to drying for 9, 12 and 14 hours were shown to achieve the water activity of 0.36-0.49. Ascorbic Acid Equivalent Antioxidant Capacity (AEAC) of guava was found to decrease for all the drying durations. Convection oven-drying of guava for 12 and 14 hours showed a significant decrease in TPC (p < 0.01) and Ferric Reducing Power Assay (FRP) (p < 0.01). Nine hours of convection oven-drying was shown to retain most of the TPC, AEAC and FRP of guava.
Beans are distinctive among a diverse and broad class of legumes. Certain health products claimed their products are high in dietary fibers and total phenolic content (TPC) because they applied bean combinations. This study aimed to determine the dietary fibers and TPC of raw and cooked beans and its combinations. Individual beans studied were kidney bean, mung bean and chickpea. Bean combinations were done by mixing each of the homogenized beans flour in the ratio of 1:1 (w/w) and 1:1:1 (w/w/w). Dietary fibers were determined using enzymaticgravimetrical method whereas TPC was determined spectrophotometrically. Results showed the insoluble dietary fiber (IDF), soluble dietary fiber (SDF), total dietary fiber (TDF) and TPC for individual raw beans varied from 20.52 to 26.61 g/100 g, 1.20 to 2.45 g/100 g, 22.08 to 27.81 g/100 g and 0.48 to 1.04 mg GAE/g, respectively. For raw bean combinations, the IDF, SDF, TDF and TPC varied from 20.74 to 23.96 g/100 g, 2.3 to 2.50 g/100 g, 23.05 to 26.46 g/100 g and 0.80 to 0.85 mg GAE/g, respectively. No significant different (p > 0.05) in IDF and SDF for raw bean combinations and individual raw beans. Meanwhile, certain raw bean combinations contained significant higher (p < 0.05) TDF and TPC than individual raw beans. The IDF, SDF, TDF and TPC for individual cooked beans varied from 14.49 to 26.30 g/100 g, 1.40 to 2.02 g/100 g, 15.88 to 28.31 g/100 g and 0.57 to 1.20 mg GAE/g, respectively. For cooked bean combinations, the IDF, SDF, TDF and TPC varied from 15.73 to 23.03 g/100 g, 1.73 to 2.36 g/100 g, 17.46 to 24.95 g/100 g and 0.61 to 1.08 mg GAE/g, respectively. After cooking, the IDF, SDF, TDF and TPC of certain beans combinations were significantly higher (p < 0.05) than individual beans. This study supports the proposal that bean combinations can possibly be used as a method to increase the amount of dietary fibers and TPC.
The utilisation of quinoa protein concentrates (QPCs) is limited due to their poor protein digestibility (78.54 %). In this study, QPCs (1 % w/v) were fermented in 5 % (v/v) water kefir grains (WKG) for 5 days at 25 °C. The protein quality of the fermented QPCs was enhanced, whereby the protein digestibility increased significantly (P
The presence of phenolic compounds in the aquatic environment has posed severe risks due to their toxicity. Among the phenolic families, nitro- and alkyl-phenolic compounds have been categorized as precedence contaminants by the United States Environmental Protection Agency (US EPA). Therefore, efficient treatment methods for wastewater containing nitro- and alkyl-phenolic compounds are urgently needed. Due to the advantages of creating reactive species and generating efficient degradation of hazardous contaminants in wastewater, advanced oxidation processes (AOPs) are well-known in the field of treating toxic contaminants. In this review paper, the recent directions in AOPs, catalysts, mechanisms, and kinetics of AOPs are comprehensively reviewed. Furthermore, the conclusion summarizes the research findings, future prospects, and opportunities for this study. The main direction of AOPs lies on the optimization of catalyst and operating parameters, with industrial applications remain as the main challenge. This review article is expected to present a summary and in-depth understanding of AOPs development; and thus, inspiring scientists to accelerate the evolution of AOPs in industrial applications.
Physicochemical and phytochemical assessment of leaf mustard (Brassica juncea L.) grown in different agroclimatic conditions is essential to highlight their compositional variability and evaluate the most suitable bunch of agroclimatic and agronomic practices. B. juncea is one of the important leafy vegetables that serve as source of vitamin A and C and iron, and plenty of antioxidants. This in situ research was executed to assess the quality variability of B. juncea grown in different agroecosystems. Leaves' samples of B. juncea were procured from 15 farmers' fields exhibiting different agroclimatic conditions i.e., elevation, nutrient management, temperature, irrigation, and tillage practices. Leaves' samples were subjected to physicochemical and phytochemical analysis, i.e., moisture, pH, TSS, ascorbic acid, carotenoids, phenolics, flavonoids, and antioxidant potential. In the leaves' samples of B. juncea, the target properties were found to vary significantly (P ≤ 0.05) in different agroclimatic conditions. The moisture content, ascorbic acid, phenolic content, carotenoids, and antioxidants were found in the range of 62.7-79.3%, 74-91 mg/100 g, 49.2-49.2 mg GAE/100 g, 436.3-480 mg β carotene/100 g, 32.7-46.67%, respectively. This study elaborates the significant variation of physicochemical and phytochemical attributes of B. juncea due to the prevailing agroclimatic conditions. This necessitates the appropriate choice of B. juncea concerning its composition and ecological conditions of its cultivation in the prospective health benefits.
Chlorogenic acid (CGA) or 5-caffeoylquinic acid, was found to be the dominant phenolic compound in leaves of Etlingera elatior (Zingiberaceae). The CGA content of E. elatior leaves was significantly higher than flowers of Lonicera japonica (honeysuckle), the commercial source. In this study, a protocol to produce a standardised herbal CGA extract from leaves of E. elatior using column chromatography was developed.
Seven different brands of mouthwashes were assessed for the inhibition of growth of oral micro-organisms. The results showed wide variations in their effectiveness: Those containing cationic surfactants and complex organic nitrogenous compounds were more active than the older formulations based on phenols. A list was compiled ranking the mouthwashes according to their antimicrobial activity, which did not always agree with the manufacturer's claims or indication for use.