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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 Iron fortification of four rice cultivars in Northern Province through parboiling process(Research Symposium on Pure and Applied Sciences, 2018 Faculty of Science, University of Kelaniya, Sri Lanka, 2018) Sivashankar, S.; Gunathilake, K. D. P. P.Iron deficiency is a widespread micronutrient deficiency in humans. Use of iron supplementation tablets and iron fortified food is not common in developing countries. This study focus on parboiling as a cost-effective alternative method to fortify iron in four rice cultivars often consumed by people in low income category in the Northern Province to increase the iron concentration and bioavailability of iron in rice. Four paddy cultivars (Bg, 300, Bg 406, Mottakarupan and Pachchaperumal) were parboiled in deionized water containing FeEDTA (250 mg Fe/kg paddy rice), made by mixing ferrous sulfate (FeSO4) with ethylene diamine tetra acetic acid disodium salt (Na2EDTA) in acidic pH of 5.50 - 5.70. Iron content in rice was determined using atomic absorption spectroscopy and the bioaccessibility and bioavailability were evaluated using simulated gastrointestinal digestion and dialysis method. Triangle test was done to evaluate the sensory properties of the fortified rice using 30-untrained panelists. Addition of iron during the parboiling process resulted in increased concentration of iron (40 - 80 mg/kg) in grain compared to unfortified rice cultivars (30 - 35mg/kg) (p < 0.05) depending on the cultivar. Iron concentration in iron fortified grain was negatively correlated with the concentration of iron in unfortified grain (r = -0.812, p < 0.01). Iron retention test was conducted by rinsing the grain thoroughly three times using de-ionized water followed by oven drying at 700C for 72 hr. Iron fortified parboiled rice retained up to 75.51 - 99.67% iron after rinsing treatment. However, there was no correlation between total iron content and the magnitude of iron losses in fortified parboiled rice grains of four rice cultivars caused by rinsing (p>0.01). The bioaccessibility and bioavailability of iron in rice cultivars (unfortified and fortified) were evaluated by in vitro digestion. The bioavailability of iron in fortified rice was significantly increased compared to unfortified rice (p< 0.05) depending on rice cultivars. There was no correlation between bioavailability of iron and concentration of iron in (fortified and unfortified) rice cultivars (p > 0.01). In conclusion, Pachchaperumal rice cultivar is more suitable for iron fortification since iron fortification did not change the sensory attributes. Parboiling is an effective method to fortify iron into rice grains and iron fortified rice is a vehicle for improving iron status in rice based diets consumed by low income people.