UWU Repository :: Browsing by Author "Alakolanga, A.G.A.W."

Browsing by Author "Alakolanga, A.G.A.W."

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Analysis of Chemical Composition and Oil Yield of Cymbopogon nardus and Cymbopogon winterianus in Thanamalwila Area
(Uva Wellassa University of Sri Lanka, 2018) Gamage, T.G.K.M.; Ariyasinghe, H.A.E.N.; Alakolanga, A.G.A.W.
Citronella (Cymbopogon nardusand Cymbopogon winterianus) plant is a perennial crop which is used to extract citronella oil as a commercial product. Citronella is cultivated in Southern coastal area of Sri Lanka, mostly in Matara and Hambantota districts. Citronella cultivation is recently started in Thanamalwila area. Variety, climatic and soil condition can affect the yield and chemical composition of citronella oil. Objective of this study was to analyze and compare the oil yield and chemical composition of two species cultivated in Thanamalwila area to select the best species for oil extraction. Steam distillation technique was used to extract the citronella oil and gas chromatography-mass spectrometry (GC-MS) was followed to analyze the chemical composition. It was found significantly (P < 0.05) higher percentages of Citronellol (7.14%), Citronella! (9.02%) and Geraniol (16.01%) in Cymbopogon nardusthan in Cymbopogon winterianus in which the respective values were 4.68%, 4.81% and 6.3%. There were no significant differences between two species with respect to their Camphene, Limonene and Borneol contents. The oil yield of Cymbopogon nardus was significantly (P < 0.05) higher than that of Cymbopogon winterianus. Therefore, as far as the oil yield and chemical composition of oil are concerned, Cymbopogon nardus is the best variety to cultivate in Thanamalwila area.
Analysis of Chemical Properties and α-Amylase Inhibition of Selected Medicinal Plants for the Development of Herbal Tea
(Uva Wellassa University of Sri Lanka, 2019) Usna, J.F.; Alakolanga, A.G.A.W.
Herbal medicines are widely used around the world because of their safety, health benefits and very less or no side effects. Further, it’s known that, herbs have high content of bioactive compounds which are produced in plants through secondary metabolism. From the ancient time, the natural remedies in Siddha medicine are used to cure the non-contagious diseases such as cancer, diabetes, asthma etc. However, young generation is reluctant towards herbal remedies as there are not much scientific evidences to prove their benefits. The present study attempted to identify the chemical properties and α-amylase inhibition of selected herbs namely Solanum trilobatum, Ocimum tenuiflorum, Cardiospermum halicacabum, Acalypha indica and Plectranthus amboinicus and intents to develop herbal tea. Selected herbs were dried in an oven for 12 hours at 50℃ and infusions were prepared by boiling 1-5 g of dried sample in 100 ml of distilled water. Infusions were tested for their antioxidant properties using DPPH (1, 1-diphenyl-2picrylhydrazyl) Radical Scavenging Assay and α- amylase enzyme inhibition using di nitro salicylic acid method and finally IC50 value was also determined. The highest level of antioxidant properties has been observed in Cardiospermum halicacabum (7.7 mg mL1) while it’s also having maximum α-amylase inhibition activity (45.5 mg mL-1). Hence, sensory evaluation was done to select the best sample for consumption and it was subjected to the chemical analysis. The phytochemical analysis confirmed that all these leaf infusions contain in between the range of Anthocyanin (0.13-8.31 mg L-1), Polyphenol (115.23-236.64 mg L-1), free sugar (24.67-236.64 mg L-1). Accordingly, there is a potential to develop the herbal tea by using these five herbs.
Antifungal Activity of Endophytic Fungal Species Isolated from Apple (Malus domestica)
(Uva Wellassa University of Sri Lanka, 2016) Naseefa, M.A.; Alakolanga, A.G.A.W.
Novel natural metabolites with a microbial origin are one of the most interested areas in Natural Product Chemistry. This study was aimed to investigate the antifungal activity of endophytic fungal species isolated from apple (Malus domestica). Endophytes, which have a microbial origin, reside inside tissue without causing apparent disease to host. Fresh apple samples from local supermarket, Badulla, were first surface sterilized to limit epiphytic fungi. Potato Dextrose Agar (PDA), supplemented with chloramphenicol (100 mg mL-I) was used to isolate a Penicilium sp. and a Chrysosporium sp. at pH 5.6. Isolated endophytes were cultured in potato dextrose broth for 14 days and extracted with hexane and ethyl acetate successively. Diluted (10 %) diethyl sulfoxide was used to prepare solutions of extracts and inhibition of fungal growth was determined using disc diffusion method at five different concentrations (1000, 2000, 3000, 4000 and 5000 ppm) against Alternaria sp. and Aspergillus sp. with 100 mg mL-1 flucanazole as positive control. Effective concentrations (EC,,, and EC90) were calculated for mean inhibition percentage. Aspergillus sp. growth was highly inhibited compared to Alternaria sp. by Penicllium extract. EtOAc extract of Penicllium showed high inhibition against (Minimum Inhibitory Concentration < 1000 ppm) Alternaria sp. than Crysosporium extracts (MIC 4572.2 ppm). Brine Srimp Lethality Assay (BSLA) was also carried out with 48h old naupali. Results were noted after 24 h. Penicllium sp. extract showed a high lethal toxicity (LC50 402.078 ppm) as they may produce excess of metabolites than Crysosporium sp. The observation of different antifungal activity of the two types of endophytic fungal extracts revealed the variations in chances and rates of producing secondary metabolites. With these results, it can be concluded that, apple endophytic fungal extracts can be used to control selected phytopathogenic fungal species, but the toxicity of extracts should be considered in case of food commodity. Keywords: Endophytic fungi, Fungal extract, Bioactivities, Malus domestica, Antifungal compounds
Biological Activities of Polysaccharides Extracted from Vernonia cinerea and Vernonia zeylanica
(Uva Wellassa University of Sri Lanka, 2018) Wickramasinghe, W.M.C.N.K.; Henagamage, A.P.; Alakolanga, A.G.A.W.
Many members of the genus Vernonia are shown to have biological activity which contained important chemical compounds. In recent years, there has been a growing interest in polysaccharides obtained from higher plants that may have biological activities. This study was focused to investigate the antioxidant, antimicrobial and protease inhibition activity of crude polysaccharides extracted from Vernonia cinerea and Vernonia zeylanica. Plant materials were collected from Ankumbura forest area in Kandy district, Sri Lanka. Polysaccharides were extracted from the powdered above ground plant materials by hot water and alkali extraction methods and were fractionated seperately. FT-1R analysis was performed using potassium bromide powder for the purified polysaccharide fractions in the frequency range of 400 to 4000 cm-1.Total carbohydrate analysis and antimicrobial activity were performed using phenol sulfuric acid method and agar well diffusion method against Staphylococcus aureus and Cladosporium cladosporoides respectively. Antioxidant activity was determined by DPPH radical scavenging activity assay and OH scavenging activity assay. The highest total carbohydrate content (9.1 mg ml-') was recorded from NaOH extraction of V.zeylanica. The FTIR analysis confirmed the presence of polysaccharides, which displayed bands characteristic to O-H, C-O- C, and C-O groups. NaOH extraction of Polysaccharide from V.zeylanica displayed the highest antibacterial activity against Stapphylococcus aureus. NaOH extraction of V. zeylanica showed the highest significant scavenging abilities (p < 0.05) on hydroxyl radicals (IC50, 4.832 mg ml-1) whereas the highest significant scavenging abilities (p < 0.05) on DPPH radicals (IC50, 9.594 mg ml-1) was shown by the hot water extraction. Significant difference was not observed in all fractions for protease inhibition activity. Thus, this study reveals that polysaccharides extracted from V. zeylanica have significant biological activities.
Comparison of Oil Yields and Chemical Composition of Selections of Cymbopogon Winterianus and Cymbopogon nardus
(Uva Wellassa University of Sri Lanka, 2019-02) Mekala, L.K.D.; Ariyasinghe, H.A.E.N.; Lochana, E.A.L.; Alakolanga, A.G.A.W.
Citronella (Cymbopogon nardus and Cymbopogon winterianus) is commercially cultivated for oil extraction and Cinnamon Research Station has developed and issued several citronella selections; three superior ‘Heenpengiri’ (HGC 01, EBC 02, and EWC 01) and two superior ‘Mahapengiri’ (KSC 04 and CRC 16) to conserve the wide genetic variability and provide high yielding citronella plant materials. However, a proper scientific analysis on chemical composition and yield of these developed selections has not been carried out. This study was focused on quantitative and qualitative analysis of oil extractions from five selections mentioned above. Steam distillation technique was used to extract the citronella oil; and gas chromatography equipped with Agilent DB WAX UI column was used to analyze the chemical composition of extracted oil. This experiment was carried out using Complete Randomized Design with three replicates. According to the overall analyses, HGC 01 has high quality than other two Heenpengiri selections as it contained Citronellal (3.45%), Citronellol (8.53%) and Geraniol (18.95) values with standard while KSC 04 contained Citronellol (9.12%), Geraniol (34.74%) and Limonene (1.58%) at 95% significant level and it is better than CRC 16. The results showed that there were no significant differences between the oil yield of EBC 02 and HGC 01, HGC 01 and EWC 01 selections. The oil yield of KSC 04 was significantly higher (P=0.045) than that of CRC 16. In conclusion, HGC 01 from Cymbopogon nardus and KSC 04 from Cymbopogon winterianus can be recommended as best selections for commercial extractions.
Determination of Antioxidant and Metal Chelation Activities of Sepioteuthis lessoniana (Squid) Ink Hydrolysates
(Uva Wellassa University of Sri Lanka, 2019-02) Fernando, I.H.L.; Ediriweera, T.K.; Alakolanga, A.G.A.W.; Abeyrathne, E.D.N.S.
Big fin reef squid (Sepioteuthis lessoniana) is a widely distributed species in Northern coast of Sri Lanka and generates 52% of total body weight as waste due to high utilization in processing industry while causing a series of ecological problems and environmental pollution. As these by-products are a potential source of good bioactive compounds, this study aimed to analyze the bioactive properties of hydrolysates developed from squid crude ink. Ink sacs of S. lessoniana were collected and squeezed. Moisture, protein, ash and lipid content in crude ink were analyzed. Trypsin (1:100) was used in the preparation of enzymatic hydrolysates from lyophilized ink at pH of 7.8 by incubating at 37 °C for 0, 3, 6, 9, 12 and 24 hours followed by heat inactivation at 100 °C for 15 minutes. Best time course (3 hours) was detected using 15% SDS-PAGE and directed to develop chemical hydrolysates using 6 M NaOH (basic), 6 M HCl and 6 M Acetic acid (acidic) in 2:1 ratio respectively while incubating at 37 °C for 3 hours followed by heat inactivation at 100 °C for 15 minutes and 15% SDS-PAGE was conducted. DPPH radical scavenging assay was used to detect antioxidant activity while metal chelating activity was used to detect Fe2+ chelating activity in selected best hydrolysates. According to the proximate analysis, moisture and protein contents were 75.53±2.10% and 19.73±2.44% respectively in crude ink. DPPH scavenging assay showed a significant difference between the treatments (p<0.05) and Fe2+ chelating activity assay revealed that there was no significant difference among those three hydrolysates (p>0.05). However, highest DPPH scavenging activity and Fe2+ chelating activity values (61.54±2.96% and 30.35±3.91%) were obtained from acid hydrolysis. Accordingly, the study concluded that hydrolysates produced by incubating with 6 M HCl and 6 M Acetic acid for 3 hours followed with heat inactivation has better antioxidant and metal chelating activities compared to rest.
Determination of Factors Affecting to the Hardness of the Compound Used for Apex of Bead of Industrial Pneumatic Tyre
(Uva Wellassa University of Sri Lanka, 2016) Dharmathilaka, W.S.S.; Alakolanga, A.G.A.W.; Arachche, P. K.W.; Weerawansha, A.N.R.
The market for industrial pneumatic tyres created a demand for high hardness compounds for bead filler (apex) and sidewall support applications to increase the performance and load bearing capacity of the tyre. A number of different approaches have been used to increase the hardness of bead filler compounds. To obtain additional hardness for the bead filler compound phenolic reinforcing resins are used and mixing conditions are changed. The study was conducted to find out the factors affecting to the hardness of bead filler compound and identified their appropriate values. As well as verified those factors by performing the experiments. Through that hardness was improved to the expected limit. Effect of dumping temperature and maturation time and the interaction between maturation time and dumping temperature were checked. For that intermediate mixing was done under three different dumping temperatures and kept under three different maturation time. Obtained results were analyzed using two factor factorial analysis. There is no significant effect of dumping temperature and maturation time and also the interaction between dumping temperature and the maturation time. But highest mean hardness values are given by 18hrs of maturation time and 110 ° C dumping temperature. As the second experiment HMT incorporation stage has been changed. Generally HMT is incorporated in to 2" stage mixing but here it was incorporated in to intermediate mixing stage. Previously founded maturation time (18 hrs) and dumping temperature (110 °C) were used for the 2" experiment. Two sample t-test was applied to analyze obtained data. According to the analysis, there was a significant effect of HMT incorporation stage for the hardness of bead filler compound. It is concluded that if there is not a significant effect of dumping temperature and maturation time there is a considerable effect of dumping temperature and maturation time for the hardness. Keywords: Bead filler, Dumping temperature, Maturation time, intermediate mixing, 2" stage mixing
Determination of Factors Affecting to the Tensile Strength of Tread Compound of Pneumatic Rubber Tyre Used in Industrial Application
(Uva Wellassa University of Sri Lanka, 2016) Herath, H.M.L.P.; Alakolanga, A.G.A.W.; Wickramaarchchi, P.K.; Weerawansha, A.N.R.
There are many factors which affect the tensile strength ofpneumatic tyre tread compound. In this experiment, it is focused on mixing process parameters which affect to the tensile strength. The mixing parameters were investigated on an intermesh mixer for selected tyre tread compound. It was identified that the dumping temperature, mastication time, carbon black and silica incorporation temperature and carbon black silica feeding sequence influence the tensile strength of particular compound. The study was conducted to find out the effect of above factors to the tensile strength of tread compound and to identify their appropriate value. For that 1' stage mixing was done under three different dumping temperatures (155 °C, 160 °C, 165 °C) and three different mastication times (0 s, 20 s, 40 s) using the best combination of mastication time and dumping temperature changed carbon black silica incorporation temperature (120 °C, 140 °C) and carbon silica feeding sequence. According to the two factor factorial analysis dumping temperature significantly affect to the tensile strength. Experimental results showed that higher and lower dumping temperatures retard the strength but moderate temperature of 160 °C is the optimum. Mastication time also affect to the tensile strength but not significantly. Considering the interaction between mastication time and dumping temperature, we can conclude that it significantly affects to the tensile strength. Best combination of those factors is 40 s and 160 °C. Carbon black and silica dispersion also influence to the tensile strength of tread compound. A minimum temperature of 140 °C is necessary to gain efficient reaction between silica and silane. Feeding silica and carbon black separately avoids the restriction ofcarbon black against silica - silane reaction. Keywords: Tread compound, Tensile strength, Dumping temperature, Mastication time, Carbon black
Determination of Optimum Antioxidant Ratio for Effective Resistance on Aging of Natural Rubber based Solid Tire Tread Compound
(Uva Wellassa University of Sri Lanka, 2019) Perera, C.J.; Alakolanga, A.G.A.W.; Lochana, E.A.L.; Kularatne, S.
Antioxidants are highly effective ingredients and have a dramatic impact on the service life of the rubber product although being present at extremely low concentrations. Dosage of these chemicals depends upon the end application. The purpose of this research was to find out the optimum antioxidant ratio for effective resistance on thermo-oxidative aging of natural rubber based solid tire tread compound. Five tread compounds were prepared by varying the n-(1,3-dimethylbutyl)-n’-phenyl-p-phenylenediamine (6ppd) and 2,2,4Trimethyl-1,2-dihydroquinoline (TMQ) antioxidant (AO) ratios (AO1-AO free, AO2 - 2:1, AO3 - 1.5:1.5, AO4-1:2, AO5-2:2). AO5 was designed to test the effect of over dosage of antioxidants. Physio-mechanical properties such as tensile properties, tear strength, hardness, and abrasion resistance of five compounds were investigated before and after thermo-oxidative aging at temperature 70 ℃ for 72 hours according to the ASTM standards. Density and rebound resilience of five compounds were also investigated. According to the results obtained, percentage changing hardness, tensile strength, elongation at break and tear strength of AO1, AO2, AO3, AO4 and AO5 were (1%, 4.34%, 1.73%, 15.70%), (2%, 3.72%, 7.94%, -4.48%), (2%, 5.27%, 11.59%, 21.64%), (1%, 1.40%, 5.52%, 3.57%) and (2%, 3.99%, 1.60%, 14.19%) respectively after aging 72 hours. Hardness, modulus at 300% and abrasion resistance increases as the heat-aging time increases. The rate of decrease of tensile strength, tear strength and elongation at break was higher after aging. Result obtained for rebound was 44%, 46%, 47%, 46% and 48% respectively. Density of all five compounds were same. In conclusion as the percentage changing was minimum in AO4 and it is the best among five ratios under 72 hours aging condition.
Determination of the Effect of Water Quality on the Sensory Properties of Tea Liquor
(Uva Wellassa University of Sri Lanka, 2016) Ruwanpura, R.N.D.S.; Alakolanga, A.G.A.W.; Wanniarachchi, M.
Tea is an aromatic beverage which is demanded by consumers because of its unique taste, color and aroma also known as sensory properties of tea liquor which are influenced by several factors. The major ingredient of beverage tea is water and therefore water used to brew tea can be on sensory properties. This study was therefore, conducted to find out whether there is an effect of water quality on tea liquor properties by analysing most important water quality parameters to develop a profile of suitable water for brewing of tea comprised with optimum ranges of these water quality parameters. In this view, ten water samples were obtained from ten DS divisions of each Matara, Colombo, Ratnapura, Puttalam, Anuradhapra and Kandy districts were analyzed. This study was conducted in two steps; a sensory evaluation of teas of DUST 1 grade prepared with different water was conducted by trained panellists and a water analysis to determine the pH, Total hardness, total alkalinity, phenolphthalein alkalinity, EC andTDS. Results of water analysis showed, values for all the selected water quality parameters within districts as well as among districts were varied significantly. Therefore, it is evident that the water quality in terms of these parameters is varied within a district as well as among districts substantially. Average ranks obtained from sensory evaluation data varied pertainingto thearea hence, concluded that the area used to obtain water for brewing of tea has a significant effect on the sensory properties of tea liquor.Teas prepared from the water obtained from Deniyaya, Devinuwara, Mulatiyana, Rathnapura, Godakawela, Pelmadulla,Moratuwa, Kotte, Thimbirigasyaya, Kesbewa, Nattandiya, Dankotuwa, Rajanganaya, Thalawa, Mihinthale, Ganga IhalaKorale, Panwila, Yatinuwaraareas showed highest average ranks hence can be concluded as good in quality. Results shows a negative relationship between total hardness, electrical conductivity and total dissolved solids contents of water and tea liquor properties, yet the relationship between pH and total alkalinity parameters with tea liquor properties is insignificant. Results of the study concludes, liquor properties of tea are affected by water quality in terms of water hardness, conductivity and total dissolved solids. Approximately, total hardness of25-218 ppm, electrical conductivity of 5.45-861.1s/ cm and total dissolved solids of 3.27-51.6 ppm ranges are preferable for brewing of tea. Keywords: Water quality, Tea liquor Properties, Water quality parameters
Determination of the Variation of Biochemical Profile of Commonly Grown Tea (Camellia sinensis (L.) O. Kuntze) Cultivar of TRI 2025 in Low Country Agro-ecological Zones
(Uva Wellassa University of Sri Lanka, 2019) Nirmala, M.H.G.S.; Kaliyadasa, P.E.; Alakolanga, A.G.A.W.; Jayasinghe, H.A.S.L.; Jeewanthi, P.W.
There is a unique taste, color and aroma of low country teas compared to other types of tea grown in Sri Lanka. Those properties are governed by the biochemical composition of the tea, basically the tea leaves. However, there was no reported study related to the variation of chemical profile of tea grown in different agro-climatic regions within the low country region. Therefore, this study was conducted to determine the variation of biochemical profile of commonly grown tea (Camellia sinensis (L.) O. Kuntze) cultivar of TRI 2025. Fresh tea leaves of TRI 2025 in 5th pruning cycle were randomly collected from eight selected plantations which represent four major tea cultivating agro-climatic regions WL1a, WL1b, WL2a, WL2b in low country. The estates were selected using stratified sampling technique and samples from each stratum were selected randomly from different tea estates in a way of including two estates in each agro-climatic region. The study was conducted during the period of onset of rain, from November to December, 2018. The fresh tea leaves placed on ice immediately after harvesting and transported. The leave samples were dried at 50 °C for 12 hours and crushed into fine particles. Chemicals were extracted from each sample using 1g of leaf powder in methanol for the analysis of polyphenols and reducing sugars while phosphate buffer was used for proteins extraction. Folin Ciocalteu regent method Lawry’s method and DNS reagent method was used to determine polyphenols, free sugars and total proteins with slight modifications, respectively. This study found that significantly different polyphenol and free sugar contents (p<0.05) were in teas grown in the four agro-ecological regions in low country of Sri Lanka but free total protein contents were not shown the significant difference.
Determination of the Variation of Biochemical Properties of Selected Tea Cultivar (Camellia sinensis (L.) O. Kuntze) in Mid Country
(Uva Wellassa University of Sri Lanka, 2019) Samarakoon, S.M.I.S.; Kaliyadasa, P.E.; Alakolanga, A.G.A.W.; Jayasinghe, H.A.S.L.; Jeewanthi, P.W.
In the tea trade, quality is used to indicate the presence of special desirable attributes in the tea liquor which are detected by physical appearance, smell and taste. The biochemical properties of tea is very complex and is currently a subject of broad medicinal and toxicological studies. This study was conducted to determine the variation of selected biochemical properties (polyphenols, free sugars, and total proteins) of commonly growing tea cultivar (Camellia sinensis (L.) O. Kuntze), of TRI 2025 among all tea growing agro ecological regions in Mid Country of Sri Lanka. Fresh tea samples (two leaves and bud) were collected from same aged plants by using stratified sampling technique and samples from each stratum were selected randomly from different tea estates of each agro ecological region in Mid Country (WM1a, WM1b, WM2a, WM2b, WM3a, WM3b, IM1a, IM2a, IM2b, IM3a). Collected samples were placed on an ice and transported and oven dried at 50 ˚C for 12 hours and crushed in to fine particles. Methanol extraction was performed for the analysis of total polyphenol content and reducing sugars while phosphate buffer was used to extract samples for the analysis of proteins. The concentrations of polyphenols, proteins, and free sugars were determined by folin Ciocalteu reagent method, Lowry’s method and dinitrosalicylic acid method respectively with slight modifications. The findings of this study shown that biochemical properties of teas such as polyphenol, total protein and free sugars contents were significantly different (p <0.05) among many tea growing ago ecological zones in mid country of Sri Lanka. Maximum polyphenol, free sugar, total protein contents were recorded in WM1b, WM2a and IM2a respectively. Minimum polyphenol, free sugar, total protein contents were recorded in IM2a, IM3a and IM2a, respectively. This sets a precedent for the characterization of biochemical profiles of mid grown tea of Sri Lanka.
Determination of the Variation of Biochemical Properties of Selected Tea Cultivar (Camellia sinensis (L.) O. Kuntze) in Up Country
(Uva Wellassa University of Sri Lanka, 2019) Thiruneelan, T.; Kaliyadasa, P.E.; Alakolanga, A.G.A.W.; Jayasinghe, H.A.S.L.; Samarasinghe, B.A.
Tea has an attractive aroma, good taste, and flavor, however; these properties could vary with climatic factors including temperature, sunshine hours and rain fall prevail in different agro-ecological zones in the growing areas. Therefore, this study was conducted to evaluate the chemical composition of Tea (camellia sinensis (L) O. Kuntze) var. TRI 2025 grown in different agro-ecological zones in Up-country. Fresh tea samples of TRI 2025 (two leaves & bud) were collected from the same aged plants by using stratified sampling technique from 11 regions, viz: WU1, WU2a, WU2b, WU3, IU1, IU2, IU3a, IU3b, IU3c, IU3d, and IU3e in the up country during the onset of rains. The fresh tea leaves were placed on ice immediately after harvesting and transported. The leaves were dried in an oven at 50 oC for 12 hours and dried samples were crushed in to fine particles. Methanol extraction was performed for the analysis of total polyphenol content and reducing sugars while phosphate buffer was used to extract samples for the analysis of proteins. The concentrations of polyphenols, proteins, and free sugars were determined by Folin Ciocalteu reagent method, Lowry’s method and Dinitrosalicylic acid method respectively with slight modifications. The findings confirm that chemical properties of tea in up country showed significant (p<0.05) difference among many tea growing ago ecological zones in Up-country of Sri Lanka. Maximum polyphenol, free sugar, total protein contents were recorded in IU3e, WU3 and WU1 respectively. Minimum polyphenol, free sugar, total protein contents were recorded in WU2a, IU3a and IU3c, respectively. This study sets a precedent for the characterization of biochemical profile of all tea growing areas in Up-country of Sri Lanka.
Determination of Total Polyphenol Content of Ceylon Green Tea
(Uva Wellassa University of Sri Lanka, 2019) Sewwandika, H.K.D.; Jayathilake, M.A.N.; Alakolanga, A.G.A.W.
Green Tea is made from the leaves of the Camellia sinensis and is used most popularly as a beverage all over the world. Leaves of green tea are rich in bioactive compounds, particularly phenolic compounds which are closely associated with the sensory properties and quality of tea brew. Epicatechin (EC), epicatechin-3-gallate (ECG), epigallocatechin (EGC) and epigallocatechin-3-gallate (EGCG) are the main active ingredients of green tea and which are the major polyphenols of green tea. Ceylon green tea industry is young and growing rapidly. Green tea is produced by manufactures in mid and high elevation in Sri Lanka using steaming and pan firing methods. During the green tea manufacturing, high temperature is applied for the enzyme deactivation. Therefore, green tea is called as unfermented tea which has higher polyphenol content than black tea. The objective of the study was to determine the total polyphenol content of Ceylon green tea depending on processing method, elevations (High and Medium) and sub elevation levels in selected elevations (Uva and Western). Total polyphenol content was determined according to the International Organization for Standardization method (ISO) 14502-1:2005. The analysis showed that there is significant (P<0.05) relationship between tea making method and elevation as well as the elevation and sub elevation. According to the results, green tea manufactured in high elevation by pan firing method contained the highest level of polyphenols (25.4%) whereas the green tea manufactured in medium elevation by steaming method contained the lowest amount of polyphenols (21.2%) than others. Uva, high elevation green tea contained the highest level of polyphenols (24.5%) whereas the Uva, medium elevation green tea contained the lowest amount of polyphenols (21.3%) than others in Sri Lanka.
Development of a Flavored Jelly Incorporated with Green Tea Extract
(Uva Wellassa University of Sri Lanka, 2013) Sirisena, A.M.N.T.; Alakolanga, A.G.A.W.; Herath, H.M.S.K.; Wickramage, C.P.
Tea (Camelia sinensis) is considered as one of the most popular non-alcoholic, non-carbonated beverage all over the world. It is rich with phenolic compounds, which have more health benefits. Green tea showed a higher polyphenol content than black tea (Anesini et al., 2008). A cup of green tea (2.5 g of green tea leaves/200 ml water) may contain 90 mg of Epigallocatechin Gallate (Cabrera et al., 2006). At present, only 21% of the world tea market belongs to Sri Lanka however Sri Lankan tea industry produces 40 – 45 % of value added tea products from the total tea exports (Herath and Silva, 2011). Development of ready-to-use product by incorporating tea creates an additional value to the primary product of tea and it will attract more consumers towards. The objectives of this study were to develop a ready to serve jelly by incorporating green tea extract, and to determine total amount of polyphenol in the product, appropriate proportion of the ingredients, and the shelf life of the product. Methodology The research was conducted as three experiments. In experiment 1, the suitable jelling time and temperature combination were identified. The formulated sample was subjected for three levels of time and temperature combinations. To obtain proper texture for setting of green tea jelly, the mixture was heated up to the range of 100 – 110 C for about 5 to 10 minutes. In experiment 2, by changing the green tea extract level (0, 1, 2 and 3%), suitable amount that should be incorporated to the product was identified by seven trained evaluators. Their responses were obtained under taste, aroma, texture, color and overall acceptability parameters. Pectin, sugar, water, permitted chemicals (citric acid, ascorbic acid, sodium benzoate) and green tea extract were used as the main ingredients. In the third experiment, Apple flavor was used and by changing the flavor strength, the suitable flavor level for the product was identified. The developed flavored jelly was evaluated for taste, aroma, mouth feel and overall acceptability, using thirty non-trained evaluators. The data of the both sensory evaluations were collected through sensory ballots and their responses were obtained in five point hedonic scale. Identification of yeast and moulds, E’coli / Coliform and aerobic plate count were done in order to evaluate quality of the product and determine the shelf life of the final product samples during ten weeks of storage period under both ambient and refrigerator conditions. The media solutions were prepared according to the Sri Lankan Standards 516 in 1991. Changes in pH value and dissolved solid content of final product were determined to identify the stability of the product. As the chemical requirements of the jelly, determination of moisture, acid insoluble ash and pectin content were carried out according to the Sri Lankan Standards 585: part 5 in 1994. The polyphenol content was determined by following ISO 14502-1:2005. The cost analysis of the product was calculated by considering the expenses made for the ingredients and packing materials. The data were analyzed by Kruskal-Wallis test (non parametric) with 95 % confidence level. To select the best treatment combination, mean separation was done by Conover-Inman method (Conover, 1999). Results were analyzed through MINITAB 15 and graphical methods were used to interpret the results.
Development of a Green Tea Incorporated Mouthwash
(Uva Wellassa University of Sri Lanka, 2013) Chathurani, T.M.D.; Alakolanga, A.G.A.W.; Chandrasena, G.
Green tea extracts with other sources of polyphenol constituents are increasingly recognized as being potentially important to medicinal benefits (Amarakoon, 2004). Extensive researches have verified that green tea contributes to the promotion of oral health but the oral health benefit of the green tea is less aware by the people (Narotzki et al, 2012). Since it has a higher potential to establish a new product line as an oral hygiene product, the aim of this study was to assess the possible protective properties of green tea on oral health while using it as main natural ingredient of an alcohol free fluoride mouthwash. A few studies have been conducted for the development of green tea base mouthwash in the world. This present study is aimed to developed green tea incorporated mouthwash by addition of clove oil and the peppermint to enhance the natural flavor of the mouthwash while increasing the oral health benefits. Methodology The main objective was to prepare a green tea incorporated mouthwash. Deionized water was boiled up to 80 ºC and poured in to the beakers with 1%, 2% and 3% (w/v) of green tea and the beakers were kept in a water bath of 80 ºC for 8 minutes. The green tea brew was allowed to cool at room temperature and 1 g of peppermint, 20 μl of clove oil were added and the sample was thoroughly mixed for 1 hour with a stirrer. These mixtures were filtered using 0.45 µm filter paper and prepared samples kept in transparent plastic bottles. Sensory evaluation with 30 untrained panelists was carried out to select the best green tea, peppermint and clove oil incorporation quantity for the formulated mouthwash. Five point hedonic scale was used to evaluate samples for liquor taste (strength, bitterness), liquor color, smell, freshness after washing and the overall acceptability. The pH value of the developed mouthwash was measured with electronic pH meter. Fluoride ion was determined by direct potentiometry with Thermo Orion 5 star ISC conductivity meter using fluoride ion selective electrode. Prepared green tea mouthwash, reference and control were tested for well diffusion assay using experimental microorganisms included Candida albicans and Strephylococcs aureus and the mean zone inhibition was measured (Awadalla et al, 2011). The prepared mouthwash was subjected to a storage study by observing color and the smell at two weeks intervals and the pH of the product also measured.
Development of a Herbal Iced Tea from Broken Mixed Fannings (BMF) incorporated with Butterfly Pea Flowers (Clitoria ternatea)
(Uva Wellassa University of Sri Lanka, 2013) Bandara, K.M.H.G.A.S.; Alakolanga, A.G.A.W.; Gunathilaka, R.P.D.; Thalagoda, U.A.
Tea has been used across the world for decades without any documentation about foodborn illnesses attributable to the good sanitation practices.Tea is proven to be a healthy beverage because of the chemical compounds that contain in tea.Therefore adding a natural herb to tea can amplify the quality and the value of the beverage.Consumption of herbal tea is a one of the methods that can be put into practice to have a healty life.Clitoria ternatea is a thai herb and capable for lessen the risk of having different illnesess.The study was conducted to development of a herbal iced tea by using Clitoria ternatea flowers, Broken Mixed Fannings tea grade and mint flavor.Clitoria ternatea single petal blue flowers were collected and cleaned under running tap water.Then the flowers were air dried under room temperature and ground to obtain the desired partical size.By blending Clitoria ternatea flowers and Broken Mixed Fannings tea, five treatments were prepared. Sensory analysis was conducted by ten experienced tea tasters to acquire best dosage of Clitoria ternatea flowers and Broken Mixed Fannings tea for herbal iced tea development. Combinations of these functional ingredients extract were prepared and evaluated. Sensory Analysis was completed by using Kruskal-Wallis Test in Minitab software. Kruskal-Wallis macros were used to obtain the pairwise differences in the parameters.Conover- Inman Method was used for selection of best treatments. Sensory evaluation results exposed that there were significant differences between treatments with respects to color, taste, aroma, mouth feel and overall acceptability for beverage preference. The findings of microbial study was proved that total plate counts in the formulated beverages were secured to use even after kept for one and half months at room temperature.Results of physico-chemical analysis was revealed that eventhough the pH was decreased with the time the beverage was assured for the consumption compared with values of other beverages available in the market.
Development of a Simple and an Economical Method for Extraction of Edible Crude Fish Oil from Catla catla
(Uva Wellassa University of Sri Lanka, 2016) Dahanayaka, D.R.C.; Alakolanga, A.G.A.W.; Abeyrathne, E.D.N.S.
Fish oil is a rich source of nutrition and it provides benefits on human health. It is considered to be an important natural source of polyunsaturated fatty acids (PUFA).When considering of existing edible fish oil extraction methods, several draw backs can be identified. The objective of this study was to develop a simple, rapid, cheap, nontoxic and scale up method to extract edible crude fish oil from Catla catla. In the present study, preliminary investigations were conducted to determine the suitable solvent for fish oil extraction. According to that ethanol, acetone, propanol and hexane were selected for sequential solvent extraction since they were recommended as the food grade solvents. The results of the sequential solvent extraction showed acetone and ethanol have an excellent capacity to extract fish oil. According to yield study, separated crude lipids, high yield was resulted from 50% acetone (p < 0.05). Therefore fish skin was treated with five volumes of 50% (v/v) acetone and homogenized. The homogenate samples were kept in refrigerator at 4°C for 24 hours. Then samples were filtered through filter paper and solvents were removed through dialysis, and separated lipids were freeze dried. In the present study, physicochemical properties were obtained as iodine value (131.13 ± 7.33), peroxide value (15.53 ± 0.38) and free fatty acid value (4.48 ± 0.22) in final extracted fish oil and it was in the acceptable range. According to the results, the extracted oil has good quality and high stability. Therefore, this method is considered as simple, rapid, cheap and non-toxic. This can also be incorporated to solvent extraction of fish oil from fish which can be scaled up. Keywords: Catla calla, Ethanol, Acetone, Lipids, Nontoxic
Development of a Simple and Economical Method for Chitin Extraction from Prawn (Penaeus monodon) Shell Waste
(Uva Wellassa University of Sri Lanka, 2016) Wehella, M.N.; Alakolanga, A.G.A.W.; Abeyrathne, E.D.N. S.
Chitin is the second most important biopolymer on earth and found mainly in invertebrates and several other organisms. It exhibits a wide range of applications in biotechnology, medicine, agriculture, food processing, environmental protection and textile industry. Disposal of shell waste is a major problem in relevant processing plants. Objective of this research was to develop a simple, economical, high yielding, non-toxic and cost effective method for chitin extraction from prawn (Penaeus monodon) shell waste. Samples were collected from a local prawn processing plant and crude chitin was obtained through deproteinization, decolourization and demineralization using NaOH, butanol and citric acid respectively. Crude chitin was then converted in to chitosan by deacetylation. Purity analysis, yield analysis, physiochemical and functional properties analysis such as moisture content, Water Binding Capacity (WBC), Fat Binding Capacity (FBC) and Ce chelating activity were measured. Control was prepared using 5% (w/v) NaOH, 100% (vlv) Acetone and 1% (vlv) HC1 solution. FBC and WBC of the present study showed significantly higher values (539.20 ± 0.40', 560.00 ± 0.23') than those of control (304.66 ± 0.23', 285.06± 0.40"), respectively (p<0.05). However, results of the yield analysis did not show a significant difference between the developed method (32.40 ± 0.01) and the control (24.80 ± 0.08). A low purity value (10%) for crude chitin was showed by the developed method compared to prepared control (25%). However, OP chelating activity was significantly higher in the developed method (51%) compared to prepared control (-16%). Observations obtained in the 3 step extraction process suggested that butanol and citric acid were the most suitable chemicals compared to acetone and HC1. WBC, FBC and chelating activity of chitosan extracted by the present method can be involved in many applications. In contrast to previous studies, the present research showed that the suggested method is a simple way to extract chitin. Keywords: Chitin, Prawn shell, Demineralization, Decolourization, CeChelating activity
Development of a Simple Nontoxic Method to Extract Crude Fish Oil from Yellowfin Tuna (Thunnus albacares) Offal
(Uva Wellassa University of Sri Lanka, 2019-02) Basuru, G.M.V.T.; Kariyawasam, M.G.T.R.; Alakolanga, A.G.A.W.; Abeyrathne, E.D.N.S.
Among world fish processing industry yellowfin tuna is a dominating species that is responsible for high amount of waste generation during processing which makes a high level of by-product. Fish by-products consist with omega-3 poly unsaturated fatty acids that are vital in food and pharmaceutical industry. The study was targeted to develop an effective fish oil extracting method from yellowfin tuna gut comparing with a current existing extraction technique. The determined proximate composition of yellowfin tuna gut showed 4.87±0.2% of crude fat. The research was conducted with completely randomized design (CRD) with two treatments; wet press method (rendering) and the solvent extraction method. As the solvents Chloroform/Methanol (standard), Acetone, Petroleum ether, n-Hexane, n-Butanol and Ethanol were used separately in 1:2 ratio (Gut sample: Solvent). Finally fish oil yields were calculated on percentages and analyzed the chemical property indices (Iodine value, Peroxide value and Acid value) of extracted fish oil. The results revealed that the highest yield (88.63±2.76%) was obtained in wet press method. In solvent extraction Acetone performed the highest yield (75.26±1.85%) showing the significant difference in comparison with oil yields of Petroleum ether, Hexane, n-Butanol and Ethanol (p<0.05).Iodine value of extracted fish oil from wet press method, Chloroform/Methanol, Acetone, Petroleum ether, n-Hexane, n-Butanol and Ethanol were 109.99±0.57, 103.94±0.56, 104.70±0.47, 104.53±0.74, 103.43±0.37, 106.15±0.86, and 105.83±0.68 respectively. The obtained peroxide value (2.98±0.05) and Acid value (1.04±0.02) of wet press method also indicated higher values than the solvent extraction method which assures that solvent extraction had a low hydrolysis and low oxidation in comparison with the wet press method. As conclusion extraction with acetone is better comparing the quality of the oil extracted.

Browsing by Author "Alakolanga, A.G.A.W."

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