http://dr.lib.sjp.ac.lk/handle/123456789/1874 2026-04-23T10:32:57Z 2026-04-23T10:32:57Z Senadheera, S.P.A.S. Ekanayake, Sagarika http://dr.lib.sjp.ac.lk/handle/123456789/1879 2022-02-24T05:22:23Z 2015-08-20T04:53:45Z

Protein quality of foods made incorporating Cycas circinalis seed flour Senadheera, S.P.A.S.; Ekanayake, Sagarika Among the cycad species Cycas circinalis and Cycas zeylanica are native to Sri Lanka. Foods such as pittu and roti made by incorporating Cycas circinalis seed flour are consumed by Sri Lankans living in areas where the plant grows. Although previously reported data indicate that the content of protein in C. circinalis seeds is comparable to that of wheat flour, no data is available on the quality of cycad seed proteins. The present study was aimed at evaluating the quality of proteins in C. circinalis seed flour, pittu and roti made by incorporating cycas seed flour. The moisture, insoluble (IDF) and soluble dietary fibres (SDF), crude protein and digestible carbohydrate contents were measured by AOAC official methods (1984), method of Asp et al, Lowry’s method/ Folin Ceocalteau method and Holm’s method respectively. Quality of proteins was estimated by AOAC Official method 960.48, using an animal bioassay. Digestible carbohydrate content was highest in soaked seed flour (50.0±2.03). Among the cycad foods, highest protein content (10.3±0.01) and total dietary fibre content (7.7) were in roti and this could be due to the addition of wheat flour to roti instead of rice flour in pittu. Highest weight gain was observed in reference group fed with casein containing diet. The significantly high weight gain in the seed flour fed group compared to roti and pittu fed groups may be due to the high feed intake. No significant weight gain difference was observed between roti and pittu fed groups. Protein quality of C. circinalis seeds was comparable with that of common maize but all protein quality parameters [Protein Efficiency Ratio (PER), Food Efficiency Ratio (FER), Net Protein Retention (NPR) and Protein Retention Efficiency (PRE)] were significantly low compared to the reference protein diet. Although not significant, NPR and PRE values in roti (1.4±0.6 and 8.5±3.7) were higher than test food made with pittu or raw seed flour.

2015-08-20T04:53:45Z Idroos, F.S. Hettiarachchi, I.U. Manage, P.M. http://dr.lib.sjp.ac.lk/handle/123456789/1878 2022-02-24T05:35:34Z 2015-08-20T04:52:31Z

Optimization of a Standard Method for Enumeration of Total Cell Counts of Colonial Microcystis aeruginosa in Environmental Samples Collected from Boralasgamuwa Lake Idroos, F.S.; Hettiarachchi, I.U.; Manage, P.M. Effectiveness of alkaline hydrolysis, heating and regression method for enumeration of cells of Microcystis aeruginosa was assessed using water samples collected from Boralasgamuwa lake during the bloom period from 15th February to 15th May 2013. Alkaline hydrolysis was performed using; 0.01, 0.1 and 1.0 M of NaOH with a control. Alkaline hydrolysis at 800C with NaOH for 15 minutes followed by 30s vortexing produced single cells of all the test samples. A total of 2.34 ± 0.11 x105 cells/ml of single cells were generated during hydrolysis with 0.01 M NaOH. The use of higher NaOH molarities resulted in cell losses. The control sample which contained only distilled water resulted highest numbers of single cells (2.89 ±0.01 X 105 cells/ml). The heating method was employed by heating M. aeroginosa colonies at 40 0C, 60 0C,70 0C,80 0C and 90 0C for 15 minutes. Heating at 800C for 15 min, followed by 30s vortex-mixing produced a suspension of single cells with 2.76±0.81x105 cells/ml. A standard plot was developed for the direct enumeration of cell number against the area of M.aeroginosa colonies using 30 selected colonies. The standard plot slightly overestimated the cell counts during enumeration (2.98 0±.51x105 cells/ml).

2015-08-20T04:52:31Z Ranatunga, C.L. Jayaweera, H.H.E. Suraweera, S.K.K. Ariyaratne, T.R. http://dr.lib.sjp.ac.lk/handle/123456789/1877 2022-02-24T05:36:49Z 2015-08-20T04:51:17Z

Laboratory Simulation of Vibration Effects Met at Vehicular Road Transportation of Fruits and Vegetables Ranatunga, C.L.; Jayaweera, H.H.E.; Suraweera, S.K.K.; Ariyaratne, T.R. For studying and controlling the vibration effects present at vehicular road transportation, the quantitative estimation and laboratory simulation of the same becomes vital. Using an accelerometer, the vibration acceleration was measured in terms of power spectral density (PSD) in dB/Hz unit. Average of the maximum vertical vibration (PSDmax) levels produced by the truck over the time of experiment were 0.005 dB/Hz, 0.01 dB/Hz and 0.05 dB/Hz at the front, middle and rear of the truck-bed respectively. Vertical vibration acceleration levels present at actual vehicular road transportation were simulated at the laboratory using a fabricated electro-dynamic vibrator. PSDmax levels met at the actual road transportation by truck were simulated at the laboratory by varying the eccentric mass and the loaded-weight of the vibrator. Eccentric mass adjusted in between 200 g and 300 g permits generation of PSDmax levels of interest on the vibrator at no-load. Loading a weight in the range from 15 kg to 60 kg allows generation of the required PSDmax levels when the eccentric mass is set to 400 g. By adjusting mutually the eccentric mass and the loaded-weight, the vibrator is capable of simulating the PSDmax levels of the interest.

2015-08-20T04:51:17Z Perera, P.R.D Ekanayake, Sagarika Ranaweera, K.K.D.S. http://dr.lib.sjp.ac.lk/handle/123456789/1876 2022-02-24T05:51:16Z 2015-08-20T04:49:50Z

Free Radical Scavenging Activity and Phenolic Content of Decoctions of Some Medicinal Plants Perera, P.R.D; Ekanayake, Sagarika; Ranaweera, K.K.D.S. Free radicals are normally generated in substantial amounts in the body; excessive amounts cause oxidative damage through chain reactions forming disorders like diabetes mellitus, cardiovascular and pulmonary diseases. In diabetic conditions, a non enzymatic reaction occurs with proteins and reducing sugars forming glycated protein named Amadori products. Further rearrangement, oxidation and reduction of Amadori products leads to form Advanced Glycated End products which causing spontaneous damage to proteins in physiological system leading various complications like Nephropathy, Neuropathy ,Retinopathy and this process accompanying the formation of free radicals. In this process oxidation plays an important role to form Advanced Glycated End Products. Therefore antioxidants are highly important in prevention or slowing the glycation reaction. Humans have evolved a complex antioxidant system, but this may not be sufficient to maintain optimal cellular functions in diabetic conditions. Medicinal plants usually contain different phenolic compounds having antioxidant properties. Therefore, a study was carried out to examine the in vitro free radical scavenging activity and total phenolic content of the decoctions of plants, Cassia auriculata (Ranawara, flower) Phyllanthus emblica (Nelli, fruit) and Scoparia dulcis (Walkottamalli, whole plant) which are used in the treatment for diabetics. Three fresh samples from each plant collected from different areas where they are grown and commercial dried sample from the traditional market was selected to prepare the decoctions and compared phenolic contents and antioxidant activity. The total phenolic content of each extract was determined using Folin-Ciocalteu reagent and evaluation of free radical scavenging activity was assessed using DPPH assay and ABTS assay. Decoctions of the commercial samples of P. emblica showed the highest total phenolic content as 625 mgGAE/g and C auriculata and S dulcis showed 459 and 131 mgGAE/g respectively. Samples dried under laboratory conditions of C.auriculata had total phenolic content from 226 – 287 mgGAE/g, P.emblica from 479 -517 mgGAE/g and S dulcis from 167 – 186 mgGAE/g. The highest DPPH antioxidant activity showed the commercial sample of P. emblica as 27 μg/ml and other samples dried under laboratory conditions were in the range of 41 – 49 μg/ml. No significant difference between the DPPH activity of C. auriculata commercial sample and other samples dried in the dehydrator and were in the range of 248 -309 μg/ml while S. dulcis all the samples showed DPPH antioxidant activity from 437 – 540 μg/ml. The reference standard, Butylated Hydroxy Toluene showed 20 μg/ml. ABTS antioxidant activity was high in all commercial samples of C.auriculata, P.emblica and S. dulcis and were as 648,625 and 615 mmol/g while other samples dried using the dehydrator showed 313 – 536 mmol/g,479 -517 mmol/g and 549-550 mmol/g respectively.

2015-08-20T04:49:50Z