International Research Conference of UWU-2019

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Bioremediation of Cadmium by Microbial Biofilms Developed Through Endophytic Fungi from Selected Mangrove Species and Soil Bacteria
(Uva Wellassa University of Sri Lanka, 2019-02) Nufla, S.I.M.F.; Henagamage, A.P.
Cadmium is the most dangerous heavy metal characterized by high stability and toxicity even at low concentration. The potential use of metal-resistant microorganisms as an ecofriendly method in the treatment of heavy metal contaminated soil and water has become more important. Therefore, the biosorption removal of cadmium from aqueous solutions by using mono and mixed microbial cultures was investigated in this study. Twelve endophytic fungi were isolated from the leaves of Avicennia marina and Lumnitzera racemosa, whereas thirteen bacteria were isolated from the mangrove soil collected from the Puttalam lagoon in Puttalam district, Sri Lanka. Microbial isolates were grown in Potato Dextrose Agar and Nutrient Agar with different concentrations of Cd to select the most Cd resistant fungi and bacteria. Fungal-Bacterial Biofilms (FBB) were developed from the selected Cd resistant fungi and bacteria. The selected biofilms and mono cultures were inoculated in Cd supplemented Combine Carbon Broth (CCB) in the concentration range of 50-500 mg l-1. Concentration levels of Cd in the CCB were measured periodically using Atomic Absorption Spectroscopy. Out of three fungal (LRA, LRC and AMA) and three bacterial (SB2, SB3 and SB12) strains that showed the highest resistance against Cd, two fungal (LRA and LRC) and all three bacterial strains were selected for the formation of FBB. Screening assay revealed that LRA and SB3 strains had significantly the highest resistance against Cd (P < 0.05). The lowest significant mean Cd concentration level in CCB was observed in F2B1B3 biofilm (103.167 mg l-1) that reduced the Cd concentration level by 58.74% after sixteen days of incubation (P < 0.05). Even though all the microbial cultures showed significant reduction of Cd concentration level, biofilms except F1B1B3 (52.73%) showed much reduction than that of mono cultures. Thus, these results indicated the potential of biofilms to reduce the concentration of Cd in water very efficiently.
Comparative Study on Antioxidant Activity and Antimicrobial Activity of Sargassum ilicifolium Crude Extract Using Different Solvent Extractions
(Uva Wellassa University of Sri Lanka, 2019-02) Edirisinghe, K.E.A.N.; Bogahawaththa, B.R.S.; Abeyrathna, E.D.N.S.; Ranasinghe, M.K.
Seaweeds are used for food, pharmaceutical and biochemical applications as they possess interesting biological activities. Amongst seaweeds, brown seaweeds show excellent antimicrobial, antioxidant and antiviral properties. S. ilicifolium is an economically important, underutilized seaweed species where more research opportunities are available. Hence, the present study was conducted to determine the functional properties of crude extracts of S. ilicifolium to find the best extract to develop as an ingredient for food industry. Dried and coarsely powdered samples of S. ilicifolium were subjected to solvent extraction using methanol, ethanol, chloroform and acetone. The yield, proximate analysis of crude extracts was determined while antioxidant activity was determined using DPPH and TBARS assays. Antimicrobial activity was determined against the Staphylococcus aureus. Significantly highest extraction yield was recorded in methanolic extraction (17.18±3.20%) while 9.60±2.14%, 2.80±0.59%, and 3.60±0.37% yields were obtained from ethanol, acetone and chloroform extractions, respectively (P˂0.05). The highest carbohydrate (37.64±1.1%) and moisture (14.07±0.71%) were observed in methanolic crude extract. Highest ash content (37.15±4.90%) was observed in ethanolic crude extract. DPPH scavenging activity of the dried seaweed, methanolic and ethanolic crude extractions were 5.32±0.35%, 21.47±2.81%, 14.93±2.55% respectively (P˂0.05). The malonaldehyde produced in dried seaweeds, chloroform and acetone extractions were recorded higher while ethanolic, methanolic extractions were showed lower than control. Antimicrobial assay against S. aureus did not show resistant to all the seaweed extracts. Hence, it could be concluded that the presence of bioactive components in the crude exacts of S. ilicifolium while highest components in ethanolic and methanolic extracts. Therefore, the ethanolic extract of S. ilicifolium could be a potential source as an ingredient for food industry.
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.
A Comparison of Richness, Diversity and Antibacterial Producing Capacity of Endophytic Fungi of Cyperus iria from Three Geographical Locations in Sri Lanka
(Uva Wellassa University of Sri Lanka, 2019-02) Jayasundara, J.M.N.M.; Ratnweera, P.B.; de Silva, E.D.
Endophytic fungi living inside healthy tissues of plants are a well-established source of various biologically active secondary metabolites. Although sedges are known to harbor numerous endophytic fungi, endophytes inhabiting sedges of the family Cyperaceae have been sparsely investigated. Therefore, the current study was designed to investigate the endophytic fungal richness, diversity and the antibacterial producing capacity, of the Cyperus iria from three geographically distinct locations in Sri Lanka. Endophytic fungi were isolated from surface sterilized aerial and root segments of healthy C. iria collected from Badulla, Matale and Colombo Districts and crude ethyl acetate fungal extracts were tested for antibacterial activity against four selected bacteria; Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa and Escherichia coli at 400 μg/disc concentration using agar disc diffusion method where Gentamycin (10 μg/disc) and methanol were used as the positive and negative controls, respectively. Isolated endophytic fungi were identified using molecular techniques. Endophytic fungal richness of C. iria from the three locations namely Badulla, Matale and Colombo were 17, 34 and 23 respectively and 12, 23 and 13 fungi were isolated from aerial parts while 05, 11 and 10 fungi were isolated from root segments. Accordingly, more fungi were isolated from aerial parts than from roots. Among the isolated fungi Fusarium, Curvularia, Trichoderma, Penicillium species were the most abundant. With respect to antibacterial activity, all endophytic fungi isolated from Badulla plants, 85 % from Matale plants and 82 % from Colombo plants showed activity against at least one bacterium tested. Also irrespective of the location of the plant most fungal extracts showed activity against the Gram positive than the Gram negative bacteria. In conclusion, endophytic fungi of C. iria from all three locations showed a high fungal richness and a majority showed antibacterial activity.
Determination of Antioxidant and Metal Chelating Activities of Water Extracted Lepidocybium flavobrunneum Muscle Protein Hydrolysates
(Uva Wellassa University of Sri Lanka, 2019-02) Kumarasinghe, A.S.U.; Ediriweera, T.K.; Abeyrathne, E.D.N.S.
Lepidocybium flavobrunneum is a marine fatty fish also known as Escolar fish. Due to laxative effect and histamine poisoning many countries reject its consumption as a food leading to wastage of the fishery resources. The objective of the study was to determine the antioxidant and metal chelation activities of Fish Protein Hydrolysates produced from water extracted crude proteins of L. flavobrunneum muscles. In this study Escolar fish muscle was separated from skin and mixed with water according to 1:1, 1:2, 1:3, 1:4 ratios and they were observed under 10% SDS-PAGE gel. Crude extraction was lyophilized and hydrolyzed using Pepsin, Protease and Trypsin enzymes (1:100) under 37 °C at optimum pH conditions for 0, 3, 6, 9, 12 and 24 hours followed by heat inactivation at 100 °C for 15 minutes. Samples were examined for antioxidant activities by TBARS assay, DPPH scavenging assay, and metal chelation activity by Fe (II) chelating activity method, followed by statistical analysis of results. Since there was no any significant different between yields (p>0.05), 1:1 ratio was selected as the best extraction method. 3 hours was selected as the time of hydrolysis, for all enzyme treatments by observing 15% SDSPAGE gel images. According to results obtained from both TBARS assay and DPPH scavenging assay did not show any significance difference (p>0.05). Infact all hydrolysates showed oxidative activities while Fe (II) chelating was high in hydrolysates produced from Trypsin enzyme (37.45±3.33%) compared to rest (p>0.05). Accordingly, the study concluded that hydrolysates produced from incubating with Trypsin for 03 hours followed with heat inactivation has better metal chelating activities compared to other hydrolyzing treatments.
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.
Development of a Protocol to Reduce the Total Dissolved Solids in Effluent Treatment Plant Water
(Uva Wellassa University of Sri Lanka, 2019-02) Abeywardhane, D.G.C.B.; Fernando, A.G.M.T.D.; Withanage, N.S.
Physico-chemical analyses of effluent treatment plant water of activated carbon manufacturing factory indicate that it has high total dissolved solids. Main reason for this high total dissolved solids is the availability of high amount of sulfate ions in effluent treatment plant water. Therefore, the aims of this study were to develop an effective method to reduce the total dissolved solids level in effluent treatment plant water and to release quality water to the environment after improving the effluent treatment process. The experiment was conducted in five stages. In first stage, 4 g of calcium hydroxide was added to precipitate calcium sulfate. In second stage, 1 g of calcium hydroxide and 1 g of aluminum were added to form ettringite and in third stage, the decant was passed through 500 g of sand filter. In fourth stage, filtrate was passed through 300 g of resin and finally pH was adjusted using carbon dioxide. The addition of lime and aluminum in second stage combines with soluble sulfate and forms calcium-aluminum-sulfate compound known as ettringite. The formation of ettringite can remove other types of heavy metals also. Quality parameters of water were determined by using MYRON L- Ultra meter II- 4P II, Eco Testr pH 2 and nephelometry method of sulfate determination. The results showed that the initial total dissolved solids level of 8900 ppm in effluent treatment plant water could be reduced to 2500 ppm. It can be concluded that this developed treatment process is capable of reducing the initial total dissolved solids in effluent treatment by 70%.
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.
Development of Bioethanol from Water Hyacinth (Eichhornia crassipes) Using Cellulose Degrading Microbial Biofilm
(Uva Wellassa University of Sri Lanka, 2019-02) Thakshika, G.; Peries, C.M.; Henegamage, A.P.
Water hyacinth (Eichhornia crassipes), a persistent and invasive weed found in Sri Lanka that creates numerous problems to aquatic ecosystems. However, it is a promising candidate for bioethanol production due to its abundant availability, low cost and high yield. Currently, usage of lignocellulosic biomass is sustainable alternative to support the global demand for fossil fuels. Still, the conversion of cellulosic material to fermentable sugar is a rate-limiting step due to its highly resistant nature. Therefore, this study was focused to evaluate the efficiency of production of bioethanol from water hyacinth using cellulose degrading microbial biofilms. Microorganisms were isolated form soil sample obtained from a coir retting land in Kurunegala district and were inoculated on Carboxy Methyl Cellulose Agar to screen the most effective cellulolytic fungi and bacteria. One fungal (F2) and two bacterial isolates (B1, B3) were selected based on the cellulolytic activity. Biofilms were developed from the selected fungi and bacteria based on the high cellulolytic activity. The efficiency of the cellulolytic activity by the biofilms were evaluated using 3, 5 DNS assay. The selected biofilms were combined with 2 g of acid pre-treated water hyacinth and were kept nine days at room temperature for fermentation. Saccharomyces cerevisae served as the control. Bioethanol production was estimated by dichromate method and confirmed by FTIR analysis. Out of selected biofilms, F2B3 biofilm showed significantly higher bioethanol production (62.85 ppm, P< 0.05) than Saccharomyces cerevisae (59.81 ppm) after nine days’ of fermentation. Further, the yield of bioethanol obtained by F2B3 biofilm and Saccharomyces cerevisae from water hyacinth were 0.037% and 0.032% respectively. Therefore, there is a prospect to enhance the bioethanol production from water hyacinth using the effective biofilms.
Effect of Activated Carbon Produced from Spent Tea Leaves on Dechlorination of Water
(Uva Wellassa University of Sri Lanka, 2019-02) Ekanayake, E.M.T.S.; Alakolanga, A.G.A.W.; Herath, H.M.S.K.
Dechlorination is the process that removes total residual chlorine from water. Activated carbon can be used as a dechlorinating agent as it is an excellent adsorbent. As a precursor material for producing activated carbon there is a possibility that spent tea leaves can be used, otherwise; they will be only an agricultural waste. The objective of the present study was to evaluate the possibility of removing total chlorine residuals present in water using activated carbon produced from spent tea leaves which was activated with H2SO4 and K2CO3. The produced activated carbon was used to filter chlorinated water which has different concentrations of total residual chlorine. Retention time during filtering was changed as 0, 15 and 30 min. For the precursor material and activated carbon, FTIR, XRD and ash testing were conducted. The results showed that there is a positive correlation between chemical activating agent, initial residual chlorine concentration and retention time. Minimum total residual chlorine in the filtrate was given by H2SO4 chemical activation agent with 30 min retention time. When the initial total residual chlorine concentration was 780 ppm, it removed 100% chlorine residuals in the water regardless of the retention time. The pH of activated carbon produced using H2SO4 chemical activation agent was 7.27 whereas the other one produced using K2CO3 showed 7.41. The column of activated carbon which is produced from spent tea leaves and chemically activated using H2SO4 can be used to filter chlorinated water effectively under 30 min retention time.
Effect of α-Pinene on the Soil Bacterial and Fungal Population and Soil Organic Carbon in Eucalyptus Plantations
(Uva Wellassa University of Sri Lanka, 2019-02) Dahanayake, P.M.; Premetilake, M.M.S.N.; Henegamage, A.P.; Herath, H.M.S.K.
Nutrient cycling is essential for the stability of an ecosystem where soil microorganisms play a significant role. Some allelochemicals such as α-pinene produced by certain plant species may suppress the activity of these microorganisms. Eucalyptus, which is a popular plantation species in Sri Lanka, is known to emit α-pinene. However, its effect on soil microorganisms and soil fertility is not well known. The present study investigated the relationship between α-pinene content, soil microorganisms and soil organic carbon content in 7-year-old Eucalyptus grandis and Eucalyptus torelliana plantations. As the control plantation, an adjacent Patna grassland (previous land-use before afforestation) was used. Three subplots (20 × 20 m) were established within each site and soil was sampled up to 15 cm depth. Soil organic carbon content was measured according to the Walkley-Black method. Following a serial dilution, bacteria and fungi were cultured and CFU mL-1 was calculated. The α-pinene in soil samples was extracted using petroleum ether and was analyzed using GC-MS. According to the results, there was a significant (P<0.05) variation between organic carbon, α-pinene content and bacteria quantity between the plantations and the adjacent grasslands. However, there was no significant (P>0.05) variation in fungi quantity. The highest organic carbon content was observed in E. torelliana plantation (2.08% ±0.3), however; the highest α-pinene content was found under E. grandis plantation (0.14% ± 0.09). Interestingly, the highest bacterial count was recorded under E. grandis plantation (3.0 x 105 CFU mL-1) while the highest fungi count was recorded in grassland. There were no significant (P>0.05) correlations between the soil α-pinene content, soil bacterial and fungal count fungal and the organic carbon. There is no significant effect (P>0.05) of α-pinene content on the bacterial and fungal counts and organic carbon in young E. grandis and E. torelliana plantations.
Effects of Microbial Fermentation on the Antioxidant Potential of Cassava
(Uva Wellassa University of Sri Lanka, 2019-02) Perera, T.W.N.K.; Amarakoon, R.; Edirisinghe, E.A.A.D.
This study investigated the effects of microbial fermentation on the antioxidant potential of MU51 cassava products, developed by changing the fermentation lengths as 48 hours and 72 hours. Steps involved were grating cassava into a mash, collecting the mash into sacks, simultaneous dewatering and fermenting the mash. The fermented wet cakes obtained were further de-watered by oven-drying process to make fermented dry products. Oven-dried raw cassava and two fermented dry products were grated and powder obtained from each sample was extracted in ethanol: water (4:1volume/volume) solvent mixture. Solutions were filtered and the extracts were dried. The antioxidant potential of extracts was assessed using Phosphomolybdenum Reduction assay. Reagent solution containing (NH₄)₂MoO₄, Na₃PO₄ and H₂SO₄ was mixed with the extracts. Tubes containing the mixtures were incubated for 60 minutes at 37°C and the absorbance of Phosphomolybdenum complexes were measured at 695 nm, using Ultraviolet/Visible spectrophotometer. Total antioxidant potentials of the extracts were expressed as ascorbic acid equivalents g L⁻¹ by reference to the ascorbic acid standard calibration curve. The antioxidant potential of oven-dried raw cassava was (2.30-2.42) x10ˉ⁴ ascorbic acid equivalents g L⁻¹, that of 48 hours fermented dry product was (3.38-3.56) x10ˉ⁴ ascorbic acid equivalents g L⁻¹ and it increased to (3.92-4.20) x10ˉ⁴ ascorbic acid equivalents g L⁻¹, for 72 hours fermented dry product. Analysis of variance technique showed that antioxidant potentials were significantly different (p<0.05) among samples. Literature survey revealed that the ability of fermentation to improve antioxidant potential is due to the increase in the amounts of phenolic compounds and flavonoids, which are results of microbial hydrolysis reactions. Fermentation induces structural breakdown of plant cell walls, leading to liberation of antioxidant compounds. Fermentation significantly enhances the antioxidant potential of cassava.
Efficiency of Manganese Removal by Eichhornia crassipes and Pistia stratiotes from Contaminanted Water
(Uva Wellassa University of Sri Lanka, 2019-02) Jayawardhana, I.D.S.T.; Athula, J.A.; Thilakarathne, E.P.D.N.
Metal pollution is a major problem of water sources used for drinking purposes. Among heavy metals, Manganese (Mn) is an essential trace element for the functioning of human, animal and plants but it leads to toxicity when it exceeds the standard level. Phytoremediation can be applied to remove heavy metals from aquatic environment. Floating aquatic macrophytes are used as an environmental friendly, efficient and cheap method. In presence study two aquatic plant species, Eichhornia crassipes (Water Hyacinth) and Pistia stratiotes (Water Lettuce) were used to determine the efficiency of removing Manganese. Bioassays using Water Hyacinth and Water Lettuce were carried out with de-ionized water contaminated by three concentration series (20, 40, 60 mg L-1) of Manganese (Π) for a period of 24 days. Three replicates were carried out for each series. Water samples were taken from each series at one day intervals and remaining manganese were analyzed using Atomic Absorption Spectrometry technique. Variations of pH and electrical conductivity of water were also measured as same interval by standard techniques. Data were statistically analyzed using SPSS16.0 package. Both Eichhornia crassipes and Pistia stratiotes showed the highest removal efficiency at the lowest concentration of Manganese (20 mg L-1). Average efficiency of manganese removal from water by Eichhornia crassipes and Pistia stratiotes were 67.61% and 80.04% respectively. Higher manganese removal efficiency was observed in Pistia stratiotes than Eichhornia crassipes. There was a significant difference (p<0.05) between absorbed manganese concentrations with the time in Eichhornia crassipes, but there was no significant difference (p>0.05) in Pistia stratiotes. The results of the study revealed that the both plants can be used to remove manganese from contaminated water. However, it is needed to conduct a pilot study for the water contaminated with manganese.
Evaluation of Cadmium Ion (Cd++) Adsorption Ability of Banana Peels and Luffa Sponges
(Uva Wellassa University of Sri Lanka, 2019-02) Geethanjana, R.M.S.; Fernando, A.Y.L.
Cadmium is highly used in industries and causes harmful effects on organisms. The use of low-cost, safe, environment friendly sorbents has been investigated to remove heavy metals from aqueous waste streams of industries. This study was carried out to evaluate the cadmium ion adsorption ability of banana peels (Musa sapientum) and luffa (Luffa cylindrica) sponges. Any chemical modifications were not used for plant materials during the experiment. Water with known initial cadmium (Cd++) concentration was prepared by adding Cd ions to the cadmium free deionised water. Adsorptions were measured at three different plant material dosages of 0.25 g, 0.5 g and 1.0 g in 25 ml of deionised water with known Cd++ concentration of 5 ppm. All experiments were conducted under room temperature (27oC). Atomic Absorption Spectrometer was used to evaluate the Cd++ concentrations of samples after treatments. Time duration for each trial was 120 minutes. During first 10 minutes all samples showed their maximum Cd++ adsorption ability. The highest adsorption of 0.3575 mg/g was given by 0.25 g/25 ml (0.01 g/1 ml) of banana peel powder. The lowest adsorption of 0.0778 mg/ g was given by 1.00 g/25 ml (0.04 g/1 ml) luffa sponge powder. The results showed the potential use of banana peel and luffa sponge as bio adsorbents for cadmium ions.
Evaluation of Oxalate Chelating Properties of Selected Egg White Proteins
(Uva Wellassa University of Sri Lanka, 2019-02) Fernando, P.I.L.; Alakolanga, A.G.A.W.; Abeyrathne, E.D.N.S.
Ovalbumin, ovotransferrin, ovomucin are considered as the major egg white proteins which highly available in the egg white with remarkable functional properties such as anti-bacterial, anti-viral, metal chelating etc. Oxalate also a negative ion and anti-nutritive agent which provides precursor ions to form calcium oxalate kidney stones. According to the present studies, restriction of oxalate rich food is the main prevention factor. A very few studies have been investigated to scavenge the oxalate in the diet. Incorporating egg white proteins to scavenge oxalate will be beneficial, because egg white proteins are well known as natural proteins with many functional properties. Aim of the study was to evaluate the oxalate chelating properties of major egg white proteins: ovalbumin, ovotransferrin (Apo & Halo) and ovomucin. Oxalate (200 mg) were dissolved in 10 ml of distilled water and 0.4 g of proteins were added using triplicates separately. The samples were incubated at 4 °C for 24 hours. After centrifuging, supernatants were measured and directed to the HPLC analysis which has been carried out on RP18 column using the mobile phase of methanol: water (50: 50 v v-1) with the flow rate of 1 ml min-1 and detection wavelength was 237 nm at 1.35 ± 0.5 min retention time. Among the four proteins (P < 0.05), ovalbumin was reported the highest chelating of oxalate (128.43±4.56 mg) and lowest value was shown in apo-ovotransferrin (50.57±1.94 mg). Ovomucin also showed the high chelation of oxalate (94.68±4.24 mg) which less than to ovalbumin. There was a significant difference among the ovalbumin and ovomucin. Whereas the holo-ovotransferrin was shown the oxalate releasing activity. Ovalbumin and ovomucin were shown very good oxalate chelating activity, compare to the apo-ovotransferrin. Therefore, there is a potential to develop nutraceuticals to scavenge oxalate with oxalate chelating properties of these proteins.
Extraction of Crude Coconut Oil from Industrial Coconut Waste and Determination of Its Chemical Properties
(Uva Wellassa University of Sri Lanka, 2019-02) Karunarathne, U.H.D.A.; Alakolanga, A.G.A.W.; Abeyrathne, E.D.N.S.
Coconut oil is one of the highly beneficial natural oil with many of the hidden medicinal values. High amount of low fat coconut residue and sludge water is removed from coconut processing industry without any use. This study was conducted to extract oil from coconut residue and sludge water in order to compare the properties of extracted oil. Oil was extracted from 10 L of industrial sludge water by density separation. Low fat coconut residue was taken and oil was extracted using solvent extraction technique. N-hexane and Di-ethyl ether were two solvents used. Coconut residue (5 g) was taken and both solvents were added separately 1:1, 1:2, 1:3, 1:4 ratios and kept in water bath for 04 different time intervals (2, 4, 6, 12 h) at 37 °C. Later, the solvent was separated from the residue and kept in oven at 40 °C to remove the solvent and the oil was obtained. The physicochemical parameters were determined by standard methods using commercial coconut as control. According to the statistical results, there was a significant difference between the yields of two solvents (p<0.05) with the best yield of for N-hexane in 1:4 ratio with 4 h retention time (20.14%), whereas yield obtained from sludge was 5.00%. Proximate analysis shown that the fat content in residual coconut was 28.33 ± 0.38%. According to the chemical analysis, peroxide (mg peroxide kg-1), acid values and moisture content were 2.85±0.09, 1.39±0.01, 1.26±0.09, 1.59±0.01 and 1.36±0.03, 0.097±0.00, 0.099±0.00, 42.2±1.29, and 1.23±0.00%, 0.99±0.00%, 1.49±0.01%, 9.25±0.02% for commercial oil, hexane, ether extracted oils and sludge oil respectively. The TBARS results showed that oil extracted using hexane have less oxidation than control (p<0.05). This study concludes that low fat residue and sludge water is no longer wastage and it contains significant amount of oil with good chemical properties. However further studies need to check the composition in the extracted oils.
Extraction of Crude Collagen from Thunnus albacares (Yellowfin Tuna) Skin and Determination of Antioxidant and Metal Chelation Activities of Its Hydrolysates
(Uva Wellassa University of Sri Lanka, 2019-02) Thilanja, G.P.D.D.S.; Dissanayake, K.S.M.; Abeyrathne, E.D.N.S.
Collagen is a dominant protein in connective tissues and highly valuable in food industry. Fish processing byproducts are good alternative source for collagen. The objective of this study was to develop a simple non-toxic method to extract crude collagen from Yellowfin tuna skin and to check functional properties of its hydrolysates. Extraction procedures were conducted using acetic acid and citric acid with 0.5 M concentrations. Based on 8% SDS-PAGE gel, type I collagens were identified. Enzymatic hydrolysis was done with Protease, Trypsin and Pepsin enzymes with different time combinations (0 h, 3 h, 6 h, 9 h, 12 h and 24 h) at 37 °C after adjusting to its optimum pH level. Best hydrolysate was selected and subjected to antioxidant activity by Diphenyl-1-picryhydrazyl (DPPH) radical scavenging activity and Metal (Fe2+) chelating activity. Proximate analysis was conducted for raw skin to determine moisture, ash, crude protein, crude fat content and 59.44±0.013%, 1.91±0.37%, 28.55±1.19%, 6.83±0.30% values were obtained respectively. Hydrolysates produced after incubating for 0 h at 37 °C followed with heat inactivation was selected as the best. Hydrolyzed produced using citric acid showed lower scavenging activity (63.62%) compared to acetic acid (85.07%) (p<0.05). In both acetic and citric extractions Fe2+ chelating activity did not show significant difference among the treatments (p>0.05). According to the collagen hydrolysates incubated at 0 h at 37 °C showed good antioxidant activity with acetic acid extraction with Pepsin enzyme. This conclude that collagen hydrolysates produced using acetic acid and Pepsin showed good antioxidant activity comparing with the ascorbic acid as positive control and it could be deserved to use as good alternative source as a natural anti-oxidant in food industry.
Extraction of Crude Skin Collagen from Pterygoplichthys pardalis and Determination of Antioxidant and Metal Chelation Activities of Its Hydrolysates
(Uva Wellassa University of Sri Lanka, 2019-02) Dilhani, E.H.P.U.; Dissanayake, K.S.M.; Abeyrathne, E.D.N.S.
Collagens have a great demand in the food industry and fish skin is a safe alternative source of collagen. Pterygoplichthys pardalis is a freshwater fish which threatens endemic fish and inland aquaculture, and has no economic benefit. Objective of this study was to extract crude collagen from P. pardalis skin with simple and non-toxic method followed by identifying the antioxidant properties of its hydrolysates. Proximate composition was determined in raw fish skins with and without bony plates separately. Acid and Pepsin soluble collagens were extracted from P. pardalis skin. As with the pretreatment process of citric acid (CA) and EDTA were tested to decalcify the fish skin. Three different concentrations were used with CA as 1.2, 2.2 and 3.2 kgm-3 and for EDTA as 0.1, 0.2 and 0.3 M. Selected crude collagens were subjected to the hydrolysis using Pepsin, Protease and Trypsin enzyme after adjusting to its optimum pH with different time combinations (0, 3, 6, 9, 12 and 24 h) at 37 °C followed by heat inactivation at 100 °C for 15 min. Extracted crude collagen and best hydrolysates were selected by 8% and 15% SDS-PAGE respectively. Antioxidant activity of the best hydrolysates was evaluated using DPPH scavenging assay and metal chelation activity by Fe (II) chelating activity. All treatments were replicated (n=3). Raw fish skins with and without bony plates contained 44.29±3.69%, 58.79±1.05% moisture, 16.40±0.93%, 5.38±1.61% ash, 26.75±8.93%, 26.89±3.25% crude protein respectively. Extracted collagens with CA treatment showed higher yield compared to EDTA treatment (p<0.05). The Antioxidant properties were not significantly different (p>0.05) but metal chelation activities of selected best hydrolysates were higher in CA than EDTA treatment (p<0.05). These results conclude that collagen hydrolysates produced from P. pardalis with all three enzymes with 0 h at 37 °C followed by heat inactivation have good antioxidant and metal chelating properties.
Identification of Retting Enhancing Microbial Strains in Coconut Fibre Extraction
(Uva Wellassa University of Sri Lanka, 2019-02) Thilakarathna, H.M.N.P.; Fernando, J.A.K.M.; Dharmarathne, T.T.D.; Senavirathna, A.M.W.K.
Coir fibre is extracted from coconut (Cocos nucifera L.) husk. Natural retting process needs at least 3 months period for obtaining good quality bristle fibre. This study was carried out to reduce the retting time by introducing previously identified pectin and cellulose degrading microbial strains from bio chemical tests. For this experiment, coconut variety of CRIC60 from Bandirippuwa estate in Lunuwila was used. Retting experiments were carried out using five different combinations of microbes namely, Serratia rubidea, Bacillus safensis, Bacillus thuringiensis and Staphylococcus sciuri. The control was water. The experiment was carried out for two months. The coconut husk samples were collected by two week intervals and Ceylon drum machine was used for the fibre extraction. The percentages of bristle fibre and its qualities were analyzed. The ret liquor samples were also analyzed for pH and Electrical Conductivity. Tensile strength (118.39±1.9 N mm-2), breaking load (3.27±0.36 N), average length (127.11±2.39 mm) and fineness (27.26±3.33 g km-1) of initial sample were found to be increased to 145.48±3.97 N mm-2, 4.35±0.28 N, 152.01±2.52 mm and 57.29±1.31 g km-1, respectively with the treatment of coconut husks with Staphylococcus sciuri, Serratia rubidea, Bacillus safensis, Bacillus thuringiensis mixture for 4 to 8 weeks. Further, impurities (%) was reduced from 3.07±0.25 to 1.06±0.20 with this treatment. These values were satisfied with SLS Standards. Fibre percentage and the quality of ret liquor indicated by pH and Electrical Conductivity were also increased. Good quality bristle fibre can be obtained from coconut husks by treating with Staphylococcus sciuri, Serratiarubidea, Bacillus safensis, Bacillus thuringiensis consortium for 4-8 weeks.
Investigation on the Possibility of Harnessing Biogas from Spent Tea Leaf
(Uva Wellassa University of Sri Lanka, 2019-02) Rathnasuriya, M.D.D.; Perera, G.A.A.R.; Herath, H.M.S.K.
Made tea is generally used as raw material in instant tea manufacture. Spent tea the materials left after extraction of water soluble components from made tea is discarded as a waste material in instant tea manufacture. Discarding this solid waste is a costly and problematic operation. Spent tea is rich in nutrients but no effective method has yet been developed to utilize it. This study was conducted to investigate the potential of utilizing spent tea leaf in biogas production. An experiment was conducted using five different combinations (percent by mass) of spent tea leaf and cow dung as 100:0, 99:1, 80:20, 50:50 and 0:100, by using laboratory scale biogas reactor set-ups. Biogas production was measured daily by means of water displacement technique. Biogas generated (mL kg–1 of dry matter) by the above treatments were 1101.8, 988.33, 2126.17, 2069.33 and 0 respectively. Volume of biogas generated by the mixture of 80% of spent tea leaf and 20% of cow dung (2126.17 mL kg–1 of dry matter) was significantly (P<0.05) higher than that of other mixtures. Spent tea leaf can be used effectively in biogas production. Further research is suggested to optimize the process and to evaluate its feasibility.

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