Browsing by Author "Senarathna, K.G.C."
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Item Design an Extruder Machine to Make Artificial Rice(Uva Wellassa University of Sri Lanka, 2021) Sanjeewani, U.U.; De Silva, K.P.I.M.; Rukshan, R.A.T.; Senarathna, K.G.C.More than half of the world's population consume rice as a staple meal. Sri Lankans consume 2.34 million metric tons of rice per year on average. But rice shortage occurs due to natural disasters in Sri Lanka. Sri Lanka produced 1.471 million tons of paddy during the Yala cultivation season in 2019. Rice peases are procuced as a by-product during the milling process and therefore the value of the rice is droped down. As a solution of this low value products, more nutrition, taste rice varieties with good appearance can be prepared for different purposes. In order to facilitate these reqerements, artificial rice production has attracted the attention of other countries in the world. It is our defeating goal to establish this in our country too. extrusion technology is used to achieve this goal. The purpose of this study is to develop a new type of rice using extrusion technology using raw rice and other protein ingredients as raw material. Extraction is the process by which a mixed ingredient passes through a narrow opening called a die to form and get the desired shape of food. Processing flowcharts of some extruded food products ingredient storage 1. Ingredient Feeding 2. Mixing, Extrusion 3. Drying 4. Cutting 5. Packaging. this machine is designed with three main units feeding unit, compressing unit, and cutting and rolling unit. stainless steel SUS 304 is used for every part of contact with food. shape of the rice produced using this machine is basmati rice. Construction is based on Single screw extrusion. This machine can be used to produce artificial rice and content of the rice material can be modified in order to have good taste, apearace and nutritions. Indeed, it is a value addition to the grain grown in Sri Lanka and make a new quality product for the local market as well as export to the global market. Keywords: Artificial rice; Extrusion Technology; Synthetic rice; Extruder machineItem Determination of Acrylamide Formation with Different Frying Temperatures in Potato (Solanum tuberosum), Cassava (Manihot esculenta) and Sweet Potato (Ipomoea batatas)(Uva Wellassa University of Sri Lanka, 2020) Rangana, M.A.S.; Peris, C.M.; Rambukwella, R.U.W.M.C.B.; Senarathna, K.G.C.Acrylamide is a carcinogenic toxic compound formed during the frying process at high temperatures by the reaction of asparagine and reducing sugars. Due to the high consumption of fried tubers in the world, it is worthwhile to detect and quantify the acrylamide in fried foods to reduce the detrimental effects on human health. This study aimed to analyze the effect of temperature and the available nutrient content on the formation of acrylamide in three selected tuber species named as potato (Solanum tuberosum), cassava (Manihot esculenta) and sweet potato (Ipomoea batatas). Fried tuber samples were prepared by deep frying at 160°C, 180°C and 200°C separately using coconut oil until they reach the standard colour based on the colour chart recommended by the United States Department of Agriculture. Proximate analysis was carried out to determine the nutrient content of raw and fried tubers before analyzing the acrylamide. Gas Chromatography-Mass Spectrometry (GC-MS) was used to detect the acrylamide and quantification was proceeded according to a calibration curve of acrylamide standard (R2 =0.8535). Among the varieties, the potato was recorded the longest frying time and sweet potato was recorded the shortest time duration in all three different temperatures to obtain the recommended colour. Further, the highest amount of protein content was observed in potato and the lowest protein content was observed in sweet potato in raw form and the protein content reduced in all varieties dramatically with the increment of temperature. Similarly, the highest acrylamide concentration was found in potato (1125.65 µgkg-1 ) fried at 200°C and lowest acrylamide concentration was detected in sweet potatoes fried at 180°C which was 84.36 µgkg-1 . Acrylamide was not detected in raw samples. Results revealed that acrylamide formation was increased with the increment of temperature and there is a significant effect of the protein content of tubers on the development of acrylamide (P < 0.05). Keywords: Acrylamide, Frying temperatures, Tubers, GC-MSItem Development of a Low-cost pH Meter using Arduino Programming(Uva Wellassa University of Sri Lanka, 2021) Naveendra, J.A.L.; Jayawickrama, J.P.A.S.; Bandara, A.M.M.; Senarathna, K.G.C.A pH meter is an electronic device that measures the acidity or alkalinity of solutions by combining a pH sensor with a temperature sensor for a complete pH meter. The study was undertaken to create a low-cost pH meter with high accuracy. It is essential to measure accurate H+ ions in water-based solutions for various purposes such as aquaculture, water quality testing. The pH meter is an essential device for laboratories such as medicine, food, and agriculture. In today’s world pH meters are very expensive and need to pay more to buy a pH meter and that is a major issue for laboratories when importing pH meters. Different varieties of pH meters are commercially available in the market. The specialty of this research is the preparation of low cost of production nearly 6 times, compared to the commercially available similar pH meters. The designed pH meter is Arduino- based and the power supply via USB. Analog voltage signals are used to take the readings. A pH glass electrode sensor of a range of 0-14 and a DS18B20 temperature sensor was used. The voltages were measured by adding the pH sensor in pH 4.01, 7.01, and 10.01 standard buffer solutions. Then a graph of the pH vs. voltage was plotted and a mathematical model to calibrate the pH sensor was created using the piece-wise linear interpolation. The temperature sensor was calibrated at 0 and 100oC. The pH and temperature readings taken by the laboratory pH meters and thermometers were compared with the designed pH meter readings. The finalized device contains a menu especially for the calibrations and the adjustments by having major 4 sections as sensor calibrations, display settings, output mode, and the about device. The accuracy is up to 2 decimal points of pH and the stabilization values are given less than 30 seconds. It is identical to a pH meter found in a standard laboratory and the outcome of the study is a low-cost pH meter. Because of its user-friendly interface, simple calibration process, and high level of accuracy at a reasonable price, the pH meter can be used instead of existing pH meters. Keywords: pH meter; Low-cost pH meter; pH sensor calibration; Temperature sensor calibration; Piece-wise linear interpolationItem Development of Novel Composite Material Using Waste Polyethylene Incorporated with Calcium Carbonate Obtained from Sri Lankan Calcite(Uva Wellassa University of Sri Lanka, 2020) Navarathne, H.G.; Senarathna, K.G.C.Today, there is a great need for the reduction of polyethylene waste to reduce environmental pollution. The main objective of this study is to develop a novel composite material using waste polyethylene reinforced with calcite to make polyethylene/calcite composite. Calcite taken from the Lanka Mineral and Chemicals (Pvt) Ltd. is used as the reinforcement for the composite and low-density polyethylene obtained from waste shopping bags is used as the polymer matrix. Sample series of octadecanoic acid-coated calcite powder and unmodified calcite nanoparticles are used to synthesis the composite. The in-situ deposition is used to synthesize nanoparticles from raw calcite. Calcite is incorporated into low-density polyethylene with different ratios and properties are characterized to obtain the optimum strength. Calcite powder is characterized using particle size analyzer, X-ray diffractometer, and Fourier transforms infrared spectroscopy. The composite is characterized by tensile tests, compression tests, and differential scanning calorimetry tests. Calcite nanoparticles obtained 23.2×10-9 m of average particle size after In-situ deposition. Only the polymeric material acquired 64.57×106 N m-2 of tensile strength and 44.62×106 N m-2 of compressive strength. Tensile strength is increased up to 69.87×106 N m-2 , 78.98×106 N m-2 , 66.41×106 N m-2 and compressive strength is reached to 90.58×106 N m-2 , 102.28×106 N m-2 , 75.98×106 N m-2 when polyethylene combined with raw calcite powder, calcite nanoparticles, and surfacemodified calcite powder (5:3 of polyethylene/calcite ratio) respectively. It provides evidence that the low-density polyethylene with calcite reinforcement attained to better mechanical properties than only the polymeric material. Keywords: Low-density polyethylene, Nanoparticles, Surface modified, In-situ depositionItem Extraction and Isolation of Anti-hyperglycemic Compounds from Cheilocostus speciosus to produce sustained release formulations(Uva Wellassa University of Sri Lanka, 2020) Induruwage, S.S.; Alakolanga, A.G.A.W.; Rathnayake, S.I.; Senarathna, K.G.C.; Wijesekara, K.B.Diabetes mellitus is one of the non-contagious diseases which has now become a major health problem all over the world. This study was conducted to identify a natural, safe, and reliable solution for “diabetes” with proper scientific validation. The objective of the study was to extract and isolate anti-hyperglycemic compounds from Cheilocostus speciosus leaves. For this, a successive extraction with diethyl ether, ethyl acetate, and ethanol using sonication at room temperature was performed to extract oven-dried (40 ℃, 48 h) leaves of C. speciosus. Percentage inhibition of the enzymes and the IC50 values were determined. But the extracts of diethyl ether and ethyl acetate did not exhibit proper percent inhibitions for both alpha-amylase and alpha-glucosidase activities. Porcine pancreatic alpha-amylase inhibitory activity was performed using the DNSA method and it was detected in ethanolic extract of C. speciosus leaves with an IC50 of 17.12 mg ml-1 and Saccharomyces cerevisiae alpha-glucosidase inhibitory activity was detected with an IC50 of 21.20 mg ml-1 . Both enzyme inhibitory activities were compared with that of commercial Acarbose (IC50 values for alpha-amylase and alpha-glucosidase enzymes are 65.44 µg ml-1 and 68.52 µg ml-1 , respectively). When comparing with acarbose, a crude extract of C. speciosus leaves show promising nature to isolate antihyperglycemic compounds. Results also indicate that the alpha-amylase and alpha-glucosidase inhibition by the ethanol extract of C. speciosus are dose dependent. Therefore, this study proves that the ethanolic leaf extract of C. speciosus has enzyme inhibitory activities toward alpha-glucosidase and alpha-amylase which may helpful for the development of an antihyperglycemic formulation to reduce the postprandial glucose level. This will be carried out by bioassay-guided fractionation and isolated active compounds will be intercalated to montmorillonite, an aluminosilicate clay with high cation exchange capacity, and large specific surface area to produce sustained release formulation. Keywords: Cheilocostus speciosus, Alpha-amylase, Alpha-glucosidase, Diabetes mellitusItem Intercalation of Acarbose into Sodium Montmorillonite for Sustained Release Formulation(Uva Wellassa University of Sri Lanka, 2020) Mihiravi, H.K.S.P.; Lochana, E.A.L.; Rathnayake, S.I.; Alakolanga, A.G.A.W.; Senarathna, K.G.C.; Premarathne, E.P.N.; Wijesekara, K.B.Among the numerous antidiabetic drugs, acarbose is the most extensively used digestive enzyme inhibitor for the treatment of Type-II diabetes. A simple and rapid UV-Vis spectroscopy method reported in the literature was modified and successfully implemented for the determination of acarbose in aqueous media. The method is based on the formation of a green-colored complex of acarbose with alkaline potassium permanganate. Concentration (in the range of 10-50 ppm) is proportional to the visible light absorbance at 426 nm wavelength, therefore, the above parameters were selected for the quantitative determination of acarbose in aqueous solution. The Beer–Lambert law is obeyed in the above-mentioned range with a coefficient of determination (r2 ) value of 0.9826. The acarbose concentration in commercial tablets was determined using this method and the recovery was 99.65 % for 40 ppm solution. Short biological half-life and more side effects of acarbose have been recurring problems, owing to its low bioavailability and low patient tolerance, respectively. The controlled release of a therapeutic agent to patients is gaining prodigious importance during the recent time and clay minerals play a major role in modulating drug delivery. The present work is focused on the intercalation of acarbose into montmorillonite (MMT) as a controlled release drug carrier. MMT is an aluminosilicate clay composed of tetrahedral layers of silica stacked between octahedral layers of alumina with negatively charged surfaces. Due to its high cation exchange capacity and large specific surface area, MMT is extensively used in the formulation of various pharmaceutical products. In this study, acarbose was successfully incorporated into MMT by stirring MMT in a 100 ppm acarbose solution and showed 22.4% intercalation at pH 6. Acarbose intercalated MMT was characterized by X-ray diffraction and Fourier transformed infrared and the presence of N-H stretching peak at 1632 cm-1 and increase of d-spacing confirmed the successful intercalation of acarbose into the interlayers of MMT. The releasing properties of the synthesized acarbose-MMT composite would be investigated in the future. .Keywords: Acarbose, Montmorillonite, Intercalation, Drug delivery, CharacterizationItem Preparation of Transparent Superhydrophobic Surface(Uva Wellassa University of Sri Lanka, 2019) Rathnayake, D.T.; Senarathna, K.G.C.In the present study, transparent superhydrophobic films on glass substrates have been extensively investigated using a simple dip coating method at room temperature. The main objective of the present study is to fabricate a transparent superhydrophobic glass surface using a surface etching method and further modification was carried out to achieve best outcomes that is required to overcome the major drawbacks of existing superhydrophobic films. The substrates were prepared by using two different chemical etchants such as Sodium hydroxide (NaOH) and Hydrogen fluoride (HF) under different deposition time. Besides, Titanium(IV) isopropoxide (Ti{OCH(CH3)2}4) was used as a precursor to fabricate a hydrophobic film on the substrate. The hydrophobicity of deposited coatings is improved by derivatization of coatings with Hexadecyltrimethoxysilane (HDTMS) as a silylating agent in ethanol for 24 h. The coated surfaces were characterized by static water contact angle (CA), water tilting angle (TA), Ultraviolet-Visible spectroscopy (UV-Vis) and Scanning Electron microscopy (SEM). The enhancement of wetting behaviour is obtained by the sandpapered substrate that is accounted for maximum static water contact angle of 112.49° under 15 min deposition time in 5 mol L-1 NaOH and 24 hrs deposition time in HDTMS. It is also evident that the minimum dynamic water tilting angle is around 10.9 for the substrate dipped in 1 mol L1 NaOH for 1hr and HDTMS for 24 hrs. Results indicate that the most of the coated surfaces attained optical transmittance above 75% in the visible region (378 nm) of the resulted spectrum. It is also evident that the transparent superhydrophobic coatings can be achieve excellent behavior properties with good optical transmission by controlling the surface roughness of the resultant coatings.