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 Klang River Basin is located in the most densely populated region in Malaysia, with its heavy concentration of industries and population. A systematic study of the pollution to this river system caused by phenolic compounds have been carried out under this project. Analyses of water samples from the Klang River by high performance liquid chromatography (HPLC) with an ultraviolet (UV) detector at 280 nm have shown the presence of some priority phenolic pollutants.
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
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.
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 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.
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.
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.
Fluorene-9-bisphenol (BHPF) is a bisphenol A substitute, which has been introduced for the production of so-called 'bisphenol A (BPA)-free' plastics. However, it has been reported that BHPF can enter living organisms through using commercial plastic bottles and cause adverse effects. To date, the majority of the toxicologic study of BHPF focused on investigating its doses above the toxicological threshold. Here, we studied the effects of BHPF on development, locomotion, neuron differentiation of the central nervous system (CNS), and the expression of genes in the hypothalamic-pituitary-thyroid (HPT) axis in zebrafish exposed to different doses of BHPF ranging from 1/5 of LD1 to LD50 (300, 500, 750, 1500, 3000, and 4500 nM). As a result, the possible hormetic effects of BHPF on regulating the HPT axis were revealed, in which low-dose BHPF positively affected the HPT axis while this regulation was inhibited as the dose increased. Underlying mechanism investigation suggested that BHPF disrupted myelination through affecting HPT axis including related genes expression and TH levels, thus causing neurotoxic characteristics. Collectively, this study provides the full understanding of the environmental impact of BHPF and its toxicity on living organisms, highlighting a substantial and generalized ongoing dose-response relationship with great implications for the usage and risk assessment of BHPF.
Baccaurea pubera is a blood red coloured fruit found exclusively in Borneo. This study was conducted to evaluate the effect of superheated steam treatment on its antioxidant properties and mineral content as well as to determine nutritional values of the fruit. The fruits were treated with superheated steam at 170 °C for 15 min prior to extraction and freeze drying. The results showed that, in comparison to the control, superheated steam treatment enhanced the total phenolic content by 147.8% (287.16 mg GAE/100 g vs. 115.87 mg GAE/100 g) and DPPH radical scavenging activity by 23.7% (66.94% vs. 54.13%). However, there were reductions, as compared to the control treatments, in total flavonoid content by 16.5% (8.29 mg QE/100 g vs. 9.93 mg QE/100 g), lycopene content by 28.6% (0.020 μg/100 g vs. 0.028 μg/100 g) and ferric reducing antioxidant power by 22.2% (844.41 mg TE/100 g vs. 1085.15 mg TE/100 g). The superheated steam treatment was also observed to reduce the mineral content of the fruit, from as little as 3.6% to as high as 52% depending upon the specific mineral.
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.
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.
The present study was conducted in order to assess the effect of various doses of acute gamma irradiation (0, 10, 15, and 20 Gy) on the improvement of bioactive compounds and their antioxidant properties of Curcuma alismatifolia var. Sweet pink. The high performance liquid chromatography (HPLC) and gas chromatography (GC) analysis uncovered that various types of phenolic, flavonoid compounds, and fatty acids gradually altered in response to radiation doses. On the other hand, antioxidant activities determined by 1,1-Diphenyl-2-picryl-hydrazyl (DPPH), ferric reduction, antioxidant power (FRAP), and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assay showed a higher irradiation level significantly increased the antioxidant properties. This study revealed an efficient effect of varying levels of gamma radiation, based on the pharmaceutical demand to enhance the accumulation and distribution of bioactive compounds such as phenolic and flavonoid compounds, fatty acids, as well as their antioxidant activities in the leaves of C. alismatifolia var. Sweet pink.
Cocoa and cocoa products have received much attention due to their significant polyphenol contents. Cocoa and cocoa products, namely cocoa liquor, cocoa powder and chocolates (milk and dark chocolates) may present varied polyphenol contents and possess different levels of antioxidant potentials. For the past ten years, at least 28 human studies have been conducted utilizing one of these cocoa products. However, questions arise on which of these products would deliver the best polyphenol contents and antioxidant effects. Moreover, the presence of methylxanthines, peptides, and minerals could synergistically enhance or reduce antioxidant properties of cocoa and cocoa products. To a greater extent, cocoa beans from different countries of origins and the methods of preparation (primary and secondary) could also partially influence the antioxidant polyphenols of cocoa products. Hence, comprehensive studies on the aforementioned factors could provide the understanding of health-promoting activities of cocoa or cocoa products components.
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.
The title aza-stilbene derivative, C14H13NO2 {systematic name: (E)-2-[(4-meth-oxy-benzyl-idene)amino]-phenol}, is a product of the condensation reaction between 4-meth-oxy-benzaldehyde and 2-amino-phenol. The mol-ecule adopts an E conformation with respect to the azomethine C=N bond and is almost planar, the dihedral angle between the two substituted benzene rings being 3.29 (4)°. The meth-oxy group is coplanar with the benzene ring to which it is attached, the Cmeth-yl-O-C-C torsion angle being -1.14 (12)°. There is an intra-molecular O-H⋯N hydrogen bond generating an S(5) ring motif. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming zigzag chains along [10-1]. The chains are linked via C-H⋯π inter-actions, forming a three-dimensional structure.
The efficiency of phenol degradation via Fenton reaction using mixture of heterogeneous goethite catalyst with homogeneous ferrous ion was analyzed as a function of three independent variables, initial concentration of phenol (60 to 100 mg /L), weight ratio of initial concentration of phenol to that of H2O2 (1: 6 to 1: 14) and, weight ratio of initial concentration of goethite catalyst to that of H2O2 (1: 0.3 to 1: 0.7). More than 90 % of phenol removal and more than 40% of TOC removal were achieved within 60 minutes of reaction. Two separate models were developed using artificial neural networks to predict degradation percentage by a combination of Fe3+ and Fe2+ catalyst. Five operational parameters were employed as inputs while phenol degradation and TOC removal were considered as outputs of the developed models. Satisfactory agreement was observed between testing data and the predicted values (R2Phenol = 0.9214 and R2TOC= 0.9082).