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Item Effect of boiling and simulated digestion on the total phenol, total flavonoid and antioxidant activity of commonly consumed legumes in Sri Lanka(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Deen, A.; Visvanathan, R.; Rathanayaka, I.; Jayewardene, B. C.; Liyanage, R.Legumes are considered as a rich source of proteins, complex carbohydrates (dietary fibers), minerals and vitamins. Owing to the fact, above legumes hold a special place in vegetarian diet. In addition, legumes are gaining attention due to their extraordinary health benefits. These health benefits are attributed to the presence of numerous bioactive compounds in legumes. Antioxidants are one such important bioactive compound present in legumes. However, processing and gastrointestinal digestion may alter the bioavailability of antioxidants in legumes. Hence, this study focuses on the effect of boiling and simulated digestion on the antioxidant capacity, phenolic and flavonoid content of chickpea, mung (MI6), cowpea (Waruni), cowpea (Dawala) and horse gram (Kollu). The raw and boiled legume samples were digested by using synthetic gastrointestinal enzymes (pepsin, pancreatin, bile extract). The total phenol (TP)content and total flavonoid (TF) content in experimental legume samples were assessed using Folin-ciocalteu method and Aluminium chloride colorimetric method, respectively. The antioxidant activity in experimental legume samples were determined using DPPH (2,2-diphenyl -1 –picrylhydrazyl), ABTS (3-ethylbenzothiazoline-6-sulphonic acid) and FRAP (Ferric reducing power) methods. All the experiments were carried out in triplicate and three factor factorial model was used to analyze the data and the level of p≤0.05 was considered significant. According to the results it shows that boiling and simulated digestion modulate the bioavailability of antioxidants and their activity. Among the raw samples, Horse gram (Kollu) showed the highest (p≤0.05) amount of phenolics (20.66±1.58 mg GAE/g), highest (p≤0.05) Fe3+ reducing activity, ABTS and DPPH radical scavenging activity while cowpea (Dawala) showed the lowest amount of phenolics (13.59±0.1 mg GAE/g) and lowest (p≤0.05) antioxidant activity. However, upon boiling, studied legumes showed (p<0.05) a reduced bioavailability of TP, TF content and reduced antioxidant activity. When considering the simulated digested samples, boiled legumes showed a significant increase (p≤0.05) in TF, TP content and antioxidant activity compared to raw samples. In-vitro digested, boiled Mung and horse gram had the highest Fe3+ reducing activity (233.90±13.10 mM/Fe2+ g-1/,233.68±37.82 mM/Fe2+ g-1) and ABTS radical scavenging activity (621.83±16.77 μmolTE/g/, 363.34±10.34 μmolTE/g). Hence, the overall results reveal that the processing and simulated digestion modulate the bioavailability of TF, TP and the antioxidant activity of above five selected legumes. Bioavailability of phenols and flavonoids were high (p≤0.05) in horse gram and mung bean compared to other legumesItem Influence and optimization of growth conditions on phenol degradation by Pseudomonas aeruginosa(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Amirthalingam, S.; Dassanayaka, M. P.; Vivehananthan, K.With their relatively high toxicity, phenol and phenolics are water pollutants of major concern. The application of phenol biodegrading agents to treat phenol in wastewater has shown promising results. Pseudomonas aeruginosa is a well recorded phenol biodegrading bacteria. However, optimal growth parameters for efficient degradation of phenol may vary from one bacteria to another. Therefore, this study focused on testing the effect of growth conditions including strength and pH of the growth medium and inoculum size on phenol degradation by P. aeruginosa and to assess the phenol degradation efficiency by adding glucose as an additional carbon source. The bacterial strain of P. aeruginosa (MH031762) isolated from petroleum contaminated site in Sri Lanka was inoculated to Mineral Salt Media (MSM) with 1200 mgL-1 phenol under different growth conditions. Three-factor factorial design with three levels was used to determine the combination effect of strength (0.5x, 1x and 2x), pH (6.5, 7 and 7.5) of the medium and inoculum size (1%, 2% and 3%) on phenol degradation. Residual phenol in the medium inoculated with bacteria was measured using 4-aminoantipyrene spectrometric method under which the duration (in hours) it took for 50% phenol degradation was calculated. Under the growth conditions found to be as optimum, the biodegradation efficiency of phenol by P. aeruginosa was further tested by adding glucose as an additional carbon source at varying concentrations (0.1%, 0.25%, 0.50%, 0.75% and 1%). Pooled t-test was performed to test the phenol degradation efficiency in bio-stimulated media with glucose. According to the results, there was no combination effect by all the 3 factors together on phenol degradation by P. aeruginosa (P = 0.186). However, a significant impact was shown by the combination of the two factors, i.e. the strength and pH of the medium (P = 0.002). According to the Tukey’s test, quickest phenol degradation resulted in the double strength (2x) MSM with pH 7.5 (71.82 h). Among the 3 levels of inoculum sizes assessed, 3% showed the highest phenol degradation rate by showing the lowest time (64±4.5 h) to achieve degradation of the amount of phenol by 50%. Further, glucose in the level of 0.1% enhanced the phenol degradation rate, by degrading the same amount of phenol within 58.9±0.2 h. In conclusion, optimal growth conditions of P. aeruginosa for fast degradation of phenol were determined as 2x MSM, pH 7.5 with 3% inoculum size. Further, addition of 0.1% glucose in the medium enhanced the phenol degradation. The findings of this study provide valuable information for designing bioremediation protocols to treat phenol in industrial wastewater.