White-rot fungi, namely Coriolus versicolor and Schizophyllum commune, were studied for the biodecolorization of textile dyeing effluent in shaker-flask experiments. The results showed that C. versicolor was able to achieve 68% color removal after 5 days of treatment while that of S. commune was 88% in 9 days. Both fungi achieved the above results in non-sterile condition with diammonium hydrogen phosphate as the nutrient supplement. On the other hand, the best COD removal of 80% was obtained with C. versicolor in 9 days in sterile effluent with yeast extract as nutrient supplement, while S. commune was able to remove 85% COD within 8 days in non-sterile textile effluent supplemented with diammonium hydrogen phosphate.
As the ponding system used to treat palm oil mill effluent (POME) frequently fails to satisfy the discharge standard in Malaysia, the present study aimed to resolve this problem using an optimized electrocoagulation process. Thus, a central composite design (CCD) module in response surface methodology was employed to optimize the interactions of process variables, namely current density, contact time and initial pH targeted on maximum removal of chemical oxygen demand (COD), colour and turbidity with satisfactory pH of discharge POME. The batch study was initially designed by CCD and statistical models of responses were subsequently derived to indicate the significant terms of interactive process variables. All models were verified by analysis of variance showing model significances with Prob > F < 0.01. The optimum performance was obtained at the current density of 56 mA/cm(2), contact time of 65 min and initial pH of 4.5, rendering complete removal of colour and turbidity with COD removal of 75.4%. The pH of post-treated POME of 7.6 was achieved, which is suitable for direct discharge. These predicted outputs were subsequently confirmed by insignificant standard deviation readings between predicted and actual values. This optimum condition also permitted the simultaneous removal of NH3-N, and various metal ions, signifying the superiority of the electrocoagulation process optimized by CCD.
The objective of this study was to investigate the performance of employing persulfate reagent in the advanced oxidation of ozone to treat stabilized landfill leachate in an ozone reactor. A central composite design (CCD) with response surface methodology (RSM) was applied to evaluate the relationships between operating variables, such as ozone and persulfate dosages, pH, and reaction time, to identify the optimum operating conditions. Quadratic models for the following four responses proved to be significant with very low probabilities (<0.0001): COD, color, NH3-N, and ozone consumption (OC). The obtained optimum conditions included a reaction time of 210 min, 30 g/m(3) ozone, 1g/1g COD0/S2O8(2-) ratio, and pH 10. The experimental results were corresponded well with predicted models (COD, color, and NH3-N removal rates of 72%, 96%, and 76%, respectively, and 0.60 (kg O3/kg COD OC). The results obtained in the stabilized leachate treatment were compared with those from other treatment processes, such as ozone only and persulfate S2O8(2-) only, to evaluate its effectiveness. The combined method (i.e., O3/S2O8(2-)) achieved higher removal efficiencies for COD, color, and NH3-N compared with other studied applications. Furthermore, the new method is more efficient than ozone/Fenton in advanced oxidation process in the treatment of the same studied leachate.
Ozonation, combined with the Fenton process (O(3)/H(2)O(2)/Fe(2+)), was used to treat matured landfill leachate. The effectiveness of the Fenton molar ratio, Fenton concentration, pH variance, and reaction time were evaluated under optimum operational conditions. The optimum removal values of chemical oxygen demand (COD), color, and NH(3)-N were found to be 65%, 98%, and 12%, respectively, for 90 min of ozonation using a Fenton molar ratio of 1 at a Fenton concentration of 0.05 mol L(-1) (1700 mg/L) H(2)O(2) and 0.05 mol L(-1) (2800 mg/L) Fe(2+) at pH 7. The maximum removal of NH(3)-N was 19% at 150 min. The ozone consumption for COD removal was 0.63 kg O(3)/kg COD. To evaluate the effectiveness, the results obtained in the treatment of stabilized leachate were compared with those obtained from other treatment processes, such as ozone alone, Fenton reaction alone, as well as combined Fenton and ozone. The combined method (i.e., O(3)/H(2)O(2)/Fe(2+)) achieved higher removal efficiencies for COD, color, and NH(3)-N compared with other studied applications.
Performance evaluation of pilot scale sub-surface constructed wetlands was carried out in treating leachate from Pulau Burung Sanitary Landfill (PBSL). The constructed wetland was planted with Cyperus haspan with sand and gravel used as substrate media. The experiment was operated for three weeks retention time and during the experimentation, the influent and effluent samples were tested for its pH, turbidity, color, total suspended solid (TSS), chemical oxygen demand (COD), biochemical oxygen demand (BOD(5)), ammonia nitrogen (NH(3)-N), Total phosphorus (TP), total nitrogen (TN) and also for heavy metals such as iron (Fe), magnesium (Mg), manganese (Mn) and zinc (Zn) concentrations. The results showed that the constructed wetlands with C. haspan were capable of removing 7.2-12.4% of pH, 39.3-86.6% of turbidity, 63.5-86.6% of color, 59.7-98.8% of TSS, 39.2-91.8% of COD, 60.8-78.7% of BOD(5), 29.8-53.8% of NH(3)-N, 59.8-99.7% of TP, 33.8-67.0% of TN, 34.9-59.0% of Fe, 29.0-75.0% of Mg, 51.2-70.5% of Mn, and 75.9-89.4% of Zn. The significance of removal was manifested in the quality of the effluent obtained at the end of the study. High removal efficiencies in the study proved that leachate could be treated effectively using subsurface constructed wetlands with C. haspan plant.
Suspended solids, colour and chemical oxygen demand (COD) are among the main pollutants in landfill leachate. Application of physical or biological processes alone is normally not sufficient to remove these constituents, especially for leachate with a lower biochemical oxygen demand (BOD)/ COD ratio. The main objective of this research was to investigate the efficiency of coagulation and flocculation processes for removing suspended solids, colour and COD from leachate produced in a semi-aerobic landfill in Penang, Malaysia. A 12-month characterization study of the leachate indicated that it had a mean annual BOD/COD ratio of 0.15 and was partially stabilized, with little further biological degradation likely to occur. Particle size analysis of the raw leachate indicated that its 50th percentile (d50) was 11.68 microm. Three types of coagulants were examined in bench scale jar test studies: aluminium sulphate (alum), ferric chloride (FeCl3) and ferrous sulphate (FeSO4). The effects of agitation speed, settling time, pH, coagulant dosages and temperature were examined. At 300 rpm of rapid mixing, 50 rpm of slow mixing, and 60 min settling time, higher removals of suspended solids (over 95%), colour (90%) and COD (43%) were achieved at pH 4 and 12. FeCl3 was found to be superior to other coagulants tested. At pH 4 and 12, fair removal of suspended solids was observed at a reasonably low coagulant dose, i.e., 600 mg L(-1); hHowever, about 2500 mg L(-1) of coagulant was required to achieve good removals at pH 6. Better removals were achieved at higher temperature. The d50 of sludge after coagulation at pH 4 with a 2500 mg L(-1) FeCl3 dose was 60.16 microm, which indicated that the particles had been removed effectively from the leachate. The results indicate that coagulation and flocculation processes can be used effectively in integrated semi-aerobic leachate treatment systems, especially for removing suspended solids, colour and COD.
The removal of concentrated colour (around 5039 Pt-Co) and chemical oxygen demand (COD; around 4142 mg L-1) from matured landfill leachate through a novel combination of humic acid extraction and coagulation with natural oil palm trunk starch (OPTS) was investigated in this study. Central composite design from response surface methodology of Design Expert-10 software executed the experimental design to correlate experimental factors with desired responses. Analysis of variance developed the quadratic model for four factors (e.g. coagulant dosage, slow mixing speed and time and centrifugation duration) and two responses (% removal of colour, COD). The model confirmed the highest colour (84.96%) and COD (48.84%) removal with a desirability function of 0.836 at the optimum condition of 1.68 g L-1 coagulant dose, 19.11 rpm slow mixing speed, 16.43 minutes for mixing time and 35.75 minutes for centrifugation duration. Better results of correlation coefficient (R2 = 0.98 and 0.96) and predicted R2 (0.94 and 0.84) indicates the model significance. Electron microscopic images display the amalgamation of flocs through bridging. Fourier transforms infrared spectra confirmed the existence of selected organic groups in OPTS, which eventually signifies the applied method.
Heterogeneous combinations of organic compounds (humic acid (HA) and fulvic acid) are the prime factor for the high concentration of colour and chemical oxygen demand (COD) in semi-aerobic stabilized landfill leachate. These organics are less biodegradable and cause a severe threat to environmental elements. Microfiltration and centrifugation processes were applied in this study to investigate the HA removal from stabilized leachate samples and its corresponding interference with COD and colour. The three-stage extraction process recovered a maximum of 1412 ± 2.5 mg/L (Pulau Burung landfill site (PBLS) leachate), 1510 ± 1.5 mg/L (Alor Pongsu landfill site (APLS leachate) at pH 1.5 and 1371 ± 2.5 mg/L (PBLS) and 1451 ± 1.5 mg/L (APLS) of HA (about 42% of the total COD concentration) at pH 2.5, which eventually indicates the process efficiency. Comparative characteristics analysis of recovered HA by scanning electron microscopy, energy-dispersive X-ray, X-ray photoelectron spectroscopy, and Fourier transform infrared significantly indicate the existence of identical elements in the recovered HA compared with the previous studies. The higher reduction (around 37%) in ultraviolet (UV) absorbance values (UV254 and UV280) in the final effluent indicates the elimination of aromaticity and conjugated double-bond compounds from leachate. Moreover, 36 and 39% COD and 39 and 44% colour removal exhibit substantial interference.
The aim of this study was to determine the effect of different ratios of low protein flour to oyster mushroom (Pleurotus sajor-caju) powder on the physicochemical properties and sensory acceptability of edible tablespoon. Fresh grey oyster mushroom was dried in a convection oven at temperature of 55.0˚C ± 2.0˚C for 20 h prior to the grinding process. The low protein flour (LPF) was then incorporated with oyster mushroom powder (OMP) at different ratios of 100:0, 96:4, 92:8, 88:12 and 84:16, before being with vegetable oil, sugar, egg white and water in formulating the edible tablespoon. The proximate analyses were carried out in triplicate for calorie content, colour profile, hardness value and morphological structure of edible tablespoon. This study revealed that with decreasing LPF and increasing OMP in the formulation, the ash content (1.24% to 1.92%), crude fat content (8.98% to 10.40%) and fiber content (0.13% to 1.24%) were observed to have increased as well as the hardness value (2042.03g to 2844.57g) and pore’s size of the morphological structure of edible tablespoon. However, the carbohydrate content (78.64% to 75.56%) significantly decreased (p>0.05) together with L* value (from 68.47 to 61.71) when the decrease was in the the percentage of LPF and an increase the percentage of OMP. The calorie content, moisture content and protein content of edible tablespoon were not significantly (p>0.05) affected by different ratios of LPF to OMP. The edible tablespoon formulated with up to 8% of OMP was accepted by the sensory panelists but further increase in OMP addition significantly decreased the degree of likeness in terms of colour, odour, taste and overall acceptability of edible tablespoon. This study suggested that oyster mushroom edible tablespoon could be potential alternative disposable cutlery which will help to reduce the use of huge amount of non-biodegradable materials for environmental conservation.
Keusahawanan sering dianggap sebagai subjek yang lebih cenderung kepada pelajar dalam bidang perniagaan tetapi tidak untuk pelajar yang mempunyai pelbagai kemahiran yang terlibat dalam bidang teknikal. Namun, ini adalah satu tanggapan yang tidak seharusnya wujud kerana Malaysia seharusnya perlu mengenal pasti kesedaran keusahawanan dalam bidang teknikal. Pada masa kini, kesedaran keusahawanan dalam bidang teknikal tertentu adalah kurang lantaran program keusahawanan lazimnya lebih tertumpu kepada pelajar InstitusiPengajian Tinggi (IPT). Misalnya, Pembangunan Keusahawanan Bumiputera adalah lebih tertumpu kepada golongan siswazah IPT, belia dan wanita. Dasar Pembangunan Keusahawanan IPT juga diperkenalkan agar modal insan dengan daya pemikiran, atribut dan nilai keusahawanan dalam kalangan IPT tempatan dapat dilahirkan. Tujuan kajian ini dijalankan adalah untuk mengenal pasti tahap kesedaran keusahawanan dalam kalangan pelajar Institut Latihan Perindustrian (ILP) di Terengganu berhubung dengan faktor keusahawanan dari aspek individu usahawan yang berbeza serta struktur dan persekitaran perniagaan. Seterusnya, mengkaji hubungan antara kesedaran keusahawanan dengan pembolehubah tidak bersandar lain yang berkait dengan kajian seperti ciri keusahawanan dan cabaran keusahawanan. Kaedah kuantitatif telah digunakan dan borang soal selidik diedarkan kepada 280 orang pelajar. Hasil analisis regresi berganda menunjukkan bahawa cabaran keusahawanan merangkumi sikap dan minat, kemahiran keusahawanan serta pendidikan dan pengetahuan keusahawanan merupakan elemen paling signifikan yang mempengaruhi kesedaran keusahawanan dalam kalangan pelajar berkemahiran diILP untuk menjadi seorang usahawan. Oleh itu, adalah sangat penting bagi kerajaan Malaysiauntuk memberi perhatian terhadap cabaran yang dihadapi oleh para pelajar ini dan mengambil tindakan terhadap segala kemungkinan yang boleh mempengaruhi atau memberi kesan kepada minat pelajar terhadap keusahawanan pada masa akan datang.
Fresh-cut pineapple has experienced an increase in demand due to its great health benefits and is rich in vitamins A, B and C. Moreover, pineapple is known as a source of the enzyme bromelain, which has therapeutic applications, such as reducing inflammation, improving digestion and treating osteoarthritis. However, bromelain generally affects the pineapple’s flavour and is less preferred by consumers due to the uncomfortable prickling and tingling sensations it brings. In the present study, two types of gases and their combination, nitrogen (N2) and carbon dioxide (CO2), were used to evaluate their impacts on reducing the tingling and prickling sensations, as well as maintaining the postharvest qualities of fresh-cut pineapple stored at 5°C for 12 days. The parameters being evaluated were the bromelain enzyme activity, flesh colour, ascorbic acid concentration, flesh firmness, soluble solids concentration (SSC), titratable acidity (TA) and sensory evaluation. No significant differences were recorded for all parameters tested. Based on the sensory evaluations, all the attributes, such as colour, aroma, texture, sweetness, sourness, tingling and prickling sensations, and overall acceptance were not affected by the different gases application. Even though no apparent effect was observed, the 30 panellists preferred the aforementioned attributes, except sourness. In conclusion, the fumigation treatments with N2 and CO2 gases were not effective in reducing the tingling and prickling sensations of pineapples cv. Morris.
Green amaranth (Amaranthus viridis L.) is one of the most popular leafy vegetables cultivated in Malaysia. Photo-selective netting is a revolutionary agricultural-technical idea, allowing traditional nets to be improved to a sophisticated level, which can impact microclimate and solar radiation as well as protect crops from pests. This study aims to investigate the growth performance of green amaranth under different three different treatments of photo-selective nets including black, and yellow shade nets and control. The assessed physiological, pre-harvest and post-harvest parameters were air temperature and relative humidity, measurement of absorption of photosynthetically active radiation (PAR), plant height, number of leaves, and dry weight. This study found that the yellow shade net showed the best performance in plant growth with the average difference in plant height (4.11 cm), average leaves number (7 leaves) and average dry weight (18.58 mg) were the highest compared to black shade net and control (without shading). In conclusion, photo-selective yellow shade net was able to enhance the growth development of green amaranth and could be applied in the large scale production to boost the growth and yield of leafy vegetables.
Pumpkin (Cucurbita maxima) is a vegetable crop which is commonly consumed as vegetables or incorporated into food products. Pumpkin flesh was reported abundant with carotenoid compounds includes α-carotene, β-carotene, β-cryptoxanthin, lutein and zeaxanthin. As this antioxidant related to the colour pigment, these nutrients highly potential to be in other parts of pumpkin such as peel and seed. Therefore, the aim of this was to determine the total lutein content in different parts of pumpkin and their antioxidant properties. The pumpkin would be collected and evaluated at the commercial maturity stage (60% to fully orange-yellow of fruit peel). The presence of the lutein properties using DPPH, FRAP and ABTS assays in different parts of pumpkin was tested by using microplate spectrophotometer and analysed statistically with SPSS version 20. Among of all pumpkin fruit parts, flesh presented the highest concentration of potential lutein extracts, followed by peel and seed, respectively. On the contrary, potential lutein extracts from the pumpkin peel had the highest antioxidant activity in terms of DPPH, FRAP and ABTS assays when compared to the lutein extracts in flesh and seeds. This study indicates that the potential lutein from Cucurbita maxima especially peel may be the alternative to be used as both natural antioxidants in food products due to increasing demand for natural food preservatives. Therefore, this study may act as a source for others to further study to optimize the usage of pumpkin by-products
This study aimed to determine the physicochemical properties of undulated surf clam (Paphia undulata) hydrolysate as affected by the degree of hydrolysis (DH). Three levels of DH of undulated surf clam hydrolysate were prepared which were DH 36.57% (without any enzymatic hydrolysis), DH 58.25% (0.5% Alcalase®; 5 min; pH 7.5; 60ºC) and DH 91.26% (1% Alcalase®; 30 min; pH 7.5; 60ºC). After protein hydrolysis, the undulated surf clam hydrolysates were centrifuged, and their supernatants were freeze-dried. This study found that the protein hydrolysate with lower DH (DH 36.57%) gave lower protein content and higher ash and fat contents compared to other samples (DH 58.25% and DH 91.26%). However, the carbohydrate content is similar in all samples (16.56-20.04%). This study also found that foaming properties (29.43-67.50%), emulsifying capacity (11.94-110.52%) and peptide solubility (57.61-94.08%) were affected by the DH. As DH increased, the emulsifying capacity decreased, while peptide solubility increased. While the foaming capacity increased with increasing DH until it reached a maximum value and level off afterwards. For colour parameters, although there were differences between L*, a* and b* values for all three samples, a fluctuating pattern was noted with DH. DH also did not affect the water-holding and oil-holding capacity of undulated surf clam hydrolysate. This study shows that certain physicochemical properties of undulated surf clam hydrolysate can be tailored by adjusting the degree of hydrolysis.
Yellow gourami (Trichopodus trichopterus) is a species native to Southeast Asia and is famous as ornamental species. However, hobbyists and farmers encounter problems where its body colour easily becomes faded in captivity. Since colour enhancer pellets are expensive, an experiment was performed to determine whether tank colour can influence the body colour intensity and growth of T. trichopterus. Four different tank colours (white, yellow, blue and green) with five replicates were tested where fish were kept under natural lighting (outdoor) conditions for two months. The results demonstrated that fish reared in green coloured tank showed an increment in its colour intensity while fish reared in white tanks increased its body weight. It can be concluded that tank colour does affect the body colour intensity and weight of T. trichopterus. This study will help farmers and hobbyists to solve colour fading problem using a cheaper way.
Pink Antigonon leptopushave potential to be commercialized as cut flowers for flower arrangement. In order to determine cut inflorescences' vase life, vase solution treatments containing Artificial Tap Water as control, salicyclic acid (SA) at 100, 200, 300 mg/L and combination of 100, 200, 300 mg/L SA with 2% sucrose were conducted. Parameters observed were vase life, relative fresh weight (RFW), vase solution uptake (VSU), flower drop (FD), flower colour, relative water content (RWC) and pH. The results showed that cut inflorescences in vase treatment containing 200 mg/L SA + 2% sucrose and 300 mg/L + 2% sucrose had 1.6 fold longer vase life than the control, showing higher water uptake and reduced flower drop by 28%.
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.
Fruit phenotypes are often hypothesised to be affected by selection by frugivores. Here, we tested two hypotheses concerning frugivore-fruit interactions from the perspective of fruit colours. We measured the spectral properties of 26 fruits and the associated leaves of plants from 2 islands in New Zealand. Visual observations were also performed to record the birds that fed on the fruits. First, we tested the fruit-foliage hypothesis, where fruit colours are assumed to be evolutionarily constrained by their own leaf colour to maximise colour contrast and fruit conspicuousness. We ran a null model analysis comparing fruit colour contrast using an avian eye model. Second, we tested the frugivore specificity hypothesis, where specific fruit colours are thought to be connected with a specific bird frugivore. We performed a regression on the number of bird visits against the fruit colour in tetrahedral colour space based on an avian eye calculation using Mantel's test. The results show that fruit colours are not constrained by their own leaf colours. There is also no relationship or pattern suggesting a link between a specific fruit colour and specific bird visitors. We suggest that although fruit colour is one of the most highly discussed components, it is not the most important single deciding factor in frugivore fruit selection.
Hibiscus rosa sinensis, a member of the Malvaceae family, is widely cultivated in the tropics as an ornamental plant. It is often planted as a fence or hedge plant, and has several forms of flowers with varying colours. It is also used in traditional medicine to induce abortion, ease menstrual cramps, assist in childbirth and relieve headache, fever and inflammation. In this study, we evaluated the antibacterial activity of H. rosa sinesis extract using a disc diffusion method. Crude petroleum ether extract, ethyl acetate extract and methanol extract from the leaves, stems and flowers of the plant were prepared using a cold extraction technique. These extracts were tested at concentrations ranging from 4 mg/disc to 0.017 mg/disc against methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia. The petroleum ether extract from the leaves, stems and flowers and methanol extract from the leaves showed inhibition zones with diameters > 12 mm against MRSA. Overall, the petroleum ether extract from flowers at concentrations of 4 mg/disc and 2 mg/disc displayed the strongest inhibition zones of 18.6 ± 2.85 mm and 18.5 ± 0.29 mm, respectively, as compared to vancomycin (30 μg/ml), which did not differ significantly from the 18.0 ± 0.10 mm size of the vancomycin (30 μg/ml) inhibition zone (p < 0.05). In conclusion, H. rosa sinensis extract is a potential antibacterial agent for treating MRSA infection.
Banana peel flour (BPF) prepared from green or ripe Cavendish and Dream banana fruits were assessed for their total starch (TS), digestible starch (DS), resistant starch (RS), total dietary fibre (TDF), soluble dietary fibre (SDF) and insoluble dietary fibre (IDF). Principal component analysis (PCA) identified that only 1 component was responsible for 93.74% of the total variance in the starch and dietary fibre components that differentiated ripe and green banana flours. Cluster analysis (CA) applied to similar data obtained two statistically significant clusters (green and ripe bananas) to indicate difference in behaviours according to the stages of ripeness based on starch and dietary fibre components. We concluded that the starch and dietary fibre components could be used to discriminate between flours prepared from peels obtained from fruits of different ripeness. The results were also suggestive of the potential of green and ripe BPF as functional ingredients in food.