B.K.K.K. jinadasa | NARA - Academia.edu (original) (raw)
Papers by B.K.K.K. jinadasa
Sri Lanka Journal of Aquatic Sciences, 2018
Arsenic Toxicity: Challenges and Solutions, 2021
Discover Food, 2022
Alginates are natural polysaccharides that are extracted from brown seaweed varieties and it is w... more Alginates are natural polysaccharides that are extracted from brown seaweed varieties and it is widely used for their rheological properties. The main step in the extraction protocol of sodium alginate is alkaline extraction. Sodium alginate was produced by dipping the seaweed in 1% formaldehyde and 2.5% of sodium carbonate solution and properties were studied following the standard methods. The amount of sodium alginate yield was 31.7% in Sargassum wightii. The moisture content and the ash content were recorded at 16.82% and 5.20%, respectively. The viscosity and the gel strength were noted as 40 vcP, 4.54 × 10–2 kN with 0.1 M CaCl2 and 6.86 × 10–2 kN with 0.2 M CaCl2 respectively. This study of the extraction method and its properties reveal that Sargassum wightii brown seaweed species have a high affinity to extract the alginate.
Discover Food, 2022
Biogenic amines are basic nitrogen compounds, which are formed due to the decarboxylation of amin... more Biogenic amines are basic nitrogen compounds, which are formed due to the decarboxylation of amino acids or/and the amination and the transformation of aldehydes and ketones. Histamine is a heterocyclic biogenic amine present in a wide range of food products, including fish and fishery products, meat and their products, and other dairy products and beverages. The present review summarizes the innovative sample preparation methods for the extraction of histamine from various sample matrices. Both solid phase and liquid phase based microextraction techniques are used for extracting histamine, but the latter ones are the most popular. Currently, all the sample preparation techniques for the histamine extraction fulfil the demand of green chemistry standards. These sample preparation procedures are presented in the present review along with their special features, advantages and disadvantages. Graphical Abstract
Journal of Environmental Professionals Sri Lanka, 2015
Food Additives & Contaminants: Part B, 2014
Food Additives & Contaminants: Part B, 2013
Food Additives & Contaminants: Part B, 2013
Mercury (Hg) is a pollutant of global importance that adversely impacts ecological and human heal... more Mercury (Hg) is a pollutant of global importance that adversely impacts ecological and human health. A total of 140 Thunnus albacores (yellowfin tuna) and 176 of Xiphias gladius (swordfish) samples collected from the Indian Ocean around Sri Lanka in the period of July 2009 to March 2010 were examined for total mercury content and used to evaluate the mercury intake of Sri Lankan population. Total mercury concentrations of muscular tissues of fish were determined using cold vapor atomic absorption spectrometry. The results indicated that the highest mercury concentration were noted in swordfish 0.90±0.52 mg/kg, wet weight and followed by yellowfin tuna (0.30±0.18 mg/kg, wet weight). The projected intake values of mercury through human consumption were calculated (µg kg-1 body wt. weekly-1) and were compared with those of provisional tolerable weekly intake (PTWI) per kg body weight as stipulated by the Food and Agriculture Organization/World Health Organization (FAO/WHO) and Joint Ex...
Abstract: Non-essential trace metals, namely mercury (Hg), cadmium (Cd), lead (Pb) and arsenic (A... more Abstract: Non-essential trace metals, namely mercury (Hg), cadmium (Cd), lead (Pb) and arsenic (As), and essential trace elements copper (Cu), iron (Fe) and zinc (Zn) found in muscle tissues were analysed and compared between female, male skipjack tuna (SJT) in the Indian Ocean, Sri Lanka. Forty-four (20 female and 24 male) individual specimens of SJT were investigated using an atomic absorption spectrometer. The mean trace elements of the male fish were determined to include Hg, 0.12; Cd, 0.02; As, 0.85; Pb, <0.52; Cu, 5.45; Fe, 20.54 and Zn, 5.15 (mg/kg ww). The values for the female fish were determined to be Hg, 0.14; Cd, 0.03; As, 0.85; Pb, <0.52; Cu, 3.75; Fe, 21.82 and Zn, 8.11 (mg/kg ww). In terms of gender, the mean trace elements in the muscle tissue of male and female did not significantly vary (p < 0.05) except Cd and Zn. The results show that, according to European legislation, the muscle tissues of SJT are generally "safe" for human consumption.
Abstract: This study was conducted to investigate the effect of storage temperatures on the shelf... more Abstract: This study was conducted to investigate the effect of storage temperatures on the shelf life of yellowfin tuna (YFT) loins by studying of microbial, chemical and organoleptic changes. Shelf life of YFT was determined through changes in total aerobic bacterial plate counts (APC), total volatile basic nitrogen (TVB-N) trimethylamine (TMA), organoleptic properties and histamine development during storage at 0, 4 and 7°C. Based on TVB-N value indices, YFT maintained an acceptable shelf life for 21, 17 and 12 days at 0, 4 and 7°C, respectively. Nevertheless, YFT was rejected earlier by the sensory panellists than their TVB-N value indicated. Histamine development was found to be lower than the European Union safety level for 100 mg/kg fish during storage at 0 and 7°C for 21 and 17 days, respectively. Aerobic bacteria initially dominated the micro-flora on YFT; however, as storage time increased, aerobic bacteria became dominant at cold storage, but the numbers exceeded the Inte...
Abstract: Sea urchin samples (Stomopneustes variolaris) were collected from the selected (three s... more Abstract: Sea urchin samples (Stomopneustes variolaris) were collected from the selected (three sampling locations) western and southern coastal area around the Sri Lanka (n = 193) from the time period of May to October, 2014. Sampled animals were measured for biometrical parameters, dissected and separated roe tissues, which were analysed for the proximate composition, fatty acid profiles (by GC), essential trace elements (by AAS), carotenoid profile and vitamin A, B1, B2, B12, C and E (By HPLC). Gonads of S. variolaris were rich in protein (11.47-18.81%), essential fatty acids (C14:0, C16:0 and C18:1 (n-9) were predominant and C12:0, C22:5 (n-6) and C22:6 (n-3) were lowest), fatty acids profiles, which revealed the higher amount of saturated fatty acids was present in the gonads of S. variolaris than the monounsaturated fatty acids and polyunsaturated fatty acids. Carotenoids (β carotene (9.4 mg/100 g)) and vitamin (higher amount of vitamin C (20 mg/100 g) was also rich with S. va...
Abstract: A high-performance liquid chromatography method is described for quantitative determina... more Abstract: A high-performance liquid chromatography method is described for quantitative determination and validation of histamine in fish and fishery product samples. Histamine is extracted from fish/fishery products by homogenizing with tri-chloro acetic acid, separated with Amberlite CG-50 resin and C18-ODS Hypersil reversed phase column at ambient temperature (25°C). Linear standard curves with high correlation coefficients were obtained. An isocratic elution program was used; the total elution time was 10 min. The method was validated by assessing the following aspects; specificity, repeatability, reproducibility, linearity, recovery, limits of detection, limit of quantification and uncertainty. The validated parameters are in good agreement with method and it is a useful tool for determining histamine in fish and fishery products.
2 Abstract: This study was conducted to investigate the effect of storage temperatures on the she... more 2 Abstract: This study was conducted to investigate the effect of storage temperatures on the shelf life of yellowfin tuna (YFT) loins by studying of microbial, chemical and organoleptic changes. Shelf life of YFT was determined through changes in total aerobic bacterial plate counts (APC), total volatile basic nitrogen (TVB-N) trimethylamine (TMA), organoleptic properties and histamine development during storage at 0, 4 and 7°C. Based on TVB-N value indices, YFT maintained an acceptable shelf life for 21, 17 and 12 days at 0, 4 and 7°C, respectively. Nevertheless, YFT was rejected earlier by the sensory panellists than their TVB-N value indicated. Histamine development was found to be lower than the European Union safety level for 100 mg/kg fish during storage at 0 and 7°C for 21 and 17 days, respectively. Aerobic bacteria initially dominated the micro-flora on YFT; however, as storage time increased, aerobic bacteria became dominant at cold storage, but the numbers exceeded the In...
Sea urchin samples (Stomopneustes variolaris) were collected from the selected (three sampling lo... more Sea urchin samples (Stomopneustes variolaris) were collected from the selected (three sampling locations) western and southern coastal area around the Sri Lanka (n = 193) from the time period of May to October, 2014. Sampled animals were measured for biometrical parameters, dissected and separated roe tissues, which were analysed for the proximate composition, fatty acid profiles (by GC), es- sential trace elements (by AAS), carotenoid profile and vitamin A, B1, B2, B12, C and E (By HPLC). Gonads of S. variolaris were rich in protein (11.47-18.81%), essential fatty acids (C14:0, C16:0 and C18:1 (n-9) were predominant and C12:0, C22:5 (n-6) and C22:6 (n-3) were lowest), fatty acids profiles, which revealed the higher amount of saturated fatty acids was present in the gonads of S. variolaris than the mono- unsaturated fatty acids and polyunsaturated fatty acids. Carotenoids (β carotene (9.4 mg/100 g)) and vitamin (higher amount of vitamin C (20 mg/100 g) was also rich with S. variolar...
This study was carried out to evaluate the quality of five marine fishes yellowfin tuna (Thunnus ... more This study was carried out to evaluate the quality of five marine fishes yellowfin tuna (Thunnus albacores, Bonnaterre, 1788), sailfish (Istiophorus platypterus, Shaw, 1792), slaya/sardine (Sardinella gibbosa, Bleeker, 1849), squid (Loligo duvaucelii, D' Orbigny, 1835) and shrimp (Fenneropenaeus indicus, H. Milne Edwards, 1837) based on total volatile base nitrogen test (TVB-N). The studied fish was collected from 19 commercial retail outlets in Sri Lanka in 2012, kept under ice and immediately transferred to laboratory for further analysis. The total volatile basic nitrogen (TVB-N) test was performed to assess the quality status of fresh fish. The limits of TVB-N for fishery products in Commission Regulation (EC) NO 2074/2005, which was ranged between 25 to 35 milligrams of nitrogen/ 100grams of fish flesh. The results of the present study revealed that base the total volatile base nitrogen (TVB-N) content, 5% of yellowfin tuna, 8% of sailfish, 12% of sardine, 100% of squids an...
Total mercury (T-Hg) concentration was measured in the hair of people who live and work in the Ne... more Total mercury (T-Hg) concentration was measured in the hair of people who live and work in the Negombo coastal area and Welimada mid country area of Sri Lanka. Hair samples were analysed for T-Hg by CVAAS (cold vapour atomic absorption spectrometry) in males (n= 52, 30 from Negombo and 22 from Welimada). Mean T-Hg level and ranged between 4.38±3.55 (>LOD-13.38) Negombo and 0.39±0.44 (>LOD-1.58) Welimada. The highest value was found in a 25 year businessman in Welimada (1.58 mg/kg), and the 28 years businessman from Negombo (13.38 mg/kg). All individuals from the Negombo area are consuming small fish to large fish ratio 1:1, and the common species are Trenched Sardines (Hurulla) and large fish like skipjack tuna (Balaya) yellowfin tuna (Kelawalla) and Treavallies (Paraw). But in some individuals in Welimada area are consuming small fish and the mean T-Hg was 0.29 mg/kg, while others have 0.67 mg/kg mean value. The 55.8% of the study population (13.6% Welimada& 86.7% Negombo) ex...
Sri Lanka Journal of Aquatic Sciences, 2018
Arsenic Toxicity: Challenges and Solutions, 2021
Discover Food, 2022
Alginates are natural polysaccharides that are extracted from brown seaweed varieties and it is w... more Alginates are natural polysaccharides that are extracted from brown seaweed varieties and it is widely used for their rheological properties. The main step in the extraction protocol of sodium alginate is alkaline extraction. Sodium alginate was produced by dipping the seaweed in 1% formaldehyde and 2.5% of sodium carbonate solution and properties were studied following the standard methods. The amount of sodium alginate yield was 31.7% in Sargassum wightii. The moisture content and the ash content were recorded at 16.82% and 5.20%, respectively. The viscosity and the gel strength were noted as 40 vcP, 4.54 × 10–2 kN with 0.1 M CaCl2 and 6.86 × 10–2 kN with 0.2 M CaCl2 respectively. This study of the extraction method and its properties reveal that Sargassum wightii brown seaweed species have a high affinity to extract the alginate.
Discover Food, 2022
Biogenic amines are basic nitrogen compounds, which are formed due to the decarboxylation of amin... more Biogenic amines are basic nitrogen compounds, which are formed due to the decarboxylation of amino acids or/and the amination and the transformation of aldehydes and ketones. Histamine is a heterocyclic biogenic amine present in a wide range of food products, including fish and fishery products, meat and their products, and other dairy products and beverages. The present review summarizes the innovative sample preparation methods for the extraction of histamine from various sample matrices. Both solid phase and liquid phase based microextraction techniques are used for extracting histamine, but the latter ones are the most popular. Currently, all the sample preparation techniques for the histamine extraction fulfil the demand of green chemistry standards. These sample preparation procedures are presented in the present review along with their special features, advantages and disadvantages. Graphical Abstract
Journal of Environmental Professionals Sri Lanka, 2015
Food Additives & Contaminants: Part B, 2014
Food Additives & Contaminants: Part B, 2013
Food Additives & Contaminants: Part B, 2013
Mercury (Hg) is a pollutant of global importance that adversely impacts ecological and human heal... more Mercury (Hg) is a pollutant of global importance that adversely impacts ecological and human health. A total of 140 Thunnus albacores (yellowfin tuna) and 176 of Xiphias gladius (swordfish) samples collected from the Indian Ocean around Sri Lanka in the period of July 2009 to March 2010 were examined for total mercury content and used to evaluate the mercury intake of Sri Lankan population. Total mercury concentrations of muscular tissues of fish were determined using cold vapor atomic absorption spectrometry. The results indicated that the highest mercury concentration were noted in swordfish 0.90±0.52 mg/kg, wet weight and followed by yellowfin tuna (0.30±0.18 mg/kg, wet weight). The projected intake values of mercury through human consumption were calculated (µg kg-1 body wt. weekly-1) and were compared with those of provisional tolerable weekly intake (PTWI) per kg body weight as stipulated by the Food and Agriculture Organization/World Health Organization (FAO/WHO) and Joint Ex...
Abstract: Non-essential trace metals, namely mercury (Hg), cadmium (Cd), lead (Pb) and arsenic (A... more Abstract: Non-essential trace metals, namely mercury (Hg), cadmium (Cd), lead (Pb) and arsenic (As), and essential trace elements copper (Cu), iron (Fe) and zinc (Zn) found in muscle tissues were analysed and compared between female, male skipjack tuna (SJT) in the Indian Ocean, Sri Lanka. Forty-four (20 female and 24 male) individual specimens of SJT were investigated using an atomic absorption spectrometer. The mean trace elements of the male fish were determined to include Hg, 0.12; Cd, 0.02; As, 0.85; Pb, <0.52; Cu, 5.45; Fe, 20.54 and Zn, 5.15 (mg/kg ww). The values for the female fish were determined to be Hg, 0.14; Cd, 0.03; As, 0.85; Pb, <0.52; Cu, 3.75; Fe, 21.82 and Zn, 8.11 (mg/kg ww). In terms of gender, the mean trace elements in the muscle tissue of male and female did not significantly vary (p < 0.05) except Cd and Zn. The results show that, according to European legislation, the muscle tissues of SJT are generally "safe" for human consumption.
Abstract: This study was conducted to investigate the effect of storage temperatures on the shelf... more Abstract: This study was conducted to investigate the effect of storage temperatures on the shelf life of yellowfin tuna (YFT) loins by studying of microbial, chemical and organoleptic changes. Shelf life of YFT was determined through changes in total aerobic bacterial plate counts (APC), total volatile basic nitrogen (TVB-N) trimethylamine (TMA), organoleptic properties and histamine development during storage at 0, 4 and 7°C. Based on TVB-N value indices, YFT maintained an acceptable shelf life for 21, 17 and 12 days at 0, 4 and 7°C, respectively. Nevertheless, YFT was rejected earlier by the sensory panellists than their TVB-N value indicated. Histamine development was found to be lower than the European Union safety level for 100 mg/kg fish during storage at 0 and 7°C for 21 and 17 days, respectively. Aerobic bacteria initially dominated the micro-flora on YFT; however, as storage time increased, aerobic bacteria became dominant at cold storage, but the numbers exceeded the Inte...
Abstract: Sea urchin samples (Stomopneustes variolaris) were collected from the selected (three s... more Abstract: Sea urchin samples (Stomopneustes variolaris) were collected from the selected (three sampling locations) western and southern coastal area around the Sri Lanka (n = 193) from the time period of May to October, 2014. Sampled animals were measured for biometrical parameters, dissected and separated roe tissues, which were analysed for the proximate composition, fatty acid profiles (by GC), essential trace elements (by AAS), carotenoid profile and vitamin A, B1, B2, B12, C and E (By HPLC). Gonads of S. variolaris were rich in protein (11.47-18.81%), essential fatty acids (C14:0, C16:0 and C18:1 (n-9) were predominant and C12:0, C22:5 (n-6) and C22:6 (n-3) were lowest), fatty acids profiles, which revealed the higher amount of saturated fatty acids was present in the gonads of S. variolaris than the monounsaturated fatty acids and polyunsaturated fatty acids. Carotenoids (β carotene (9.4 mg/100 g)) and vitamin (higher amount of vitamin C (20 mg/100 g) was also rich with S. va...
Abstract: A high-performance liquid chromatography method is described for quantitative determina... more Abstract: A high-performance liquid chromatography method is described for quantitative determination and validation of histamine in fish and fishery product samples. Histamine is extracted from fish/fishery products by homogenizing with tri-chloro acetic acid, separated with Amberlite CG-50 resin and C18-ODS Hypersil reversed phase column at ambient temperature (25°C). Linear standard curves with high correlation coefficients were obtained. An isocratic elution program was used; the total elution time was 10 min. The method was validated by assessing the following aspects; specificity, repeatability, reproducibility, linearity, recovery, limits of detection, limit of quantification and uncertainty. The validated parameters are in good agreement with method and it is a useful tool for determining histamine in fish and fishery products.
2 Abstract: This study was conducted to investigate the effect of storage temperatures on the she... more 2 Abstract: This study was conducted to investigate the effect of storage temperatures on the shelf life of yellowfin tuna (YFT) loins by studying of microbial, chemical and organoleptic changes. Shelf life of YFT was determined through changes in total aerobic bacterial plate counts (APC), total volatile basic nitrogen (TVB-N) trimethylamine (TMA), organoleptic properties and histamine development during storage at 0, 4 and 7°C. Based on TVB-N value indices, YFT maintained an acceptable shelf life for 21, 17 and 12 days at 0, 4 and 7°C, respectively. Nevertheless, YFT was rejected earlier by the sensory panellists than their TVB-N value indicated. Histamine development was found to be lower than the European Union safety level for 100 mg/kg fish during storage at 0 and 7°C for 21 and 17 days, respectively. Aerobic bacteria initially dominated the micro-flora on YFT; however, as storage time increased, aerobic bacteria became dominant at cold storage, but the numbers exceeded the In...
Sea urchin samples (Stomopneustes variolaris) were collected from the selected (three sampling lo... more Sea urchin samples (Stomopneustes variolaris) were collected from the selected (three sampling locations) western and southern coastal area around the Sri Lanka (n = 193) from the time period of May to October, 2014. Sampled animals were measured for biometrical parameters, dissected and separated roe tissues, which were analysed for the proximate composition, fatty acid profiles (by GC), es- sential trace elements (by AAS), carotenoid profile and vitamin A, B1, B2, B12, C and E (By HPLC). Gonads of S. variolaris were rich in protein (11.47-18.81%), essential fatty acids (C14:0, C16:0 and C18:1 (n-9) were predominant and C12:0, C22:5 (n-6) and C22:6 (n-3) were lowest), fatty acids profiles, which revealed the higher amount of saturated fatty acids was present in the gonads of S. variolaris than the mono- unsaturated fatty acids and polyunsaturated fatty acids. Carotenoids (β carotene (9.4 mg/100 g)) and vitamin (higher amount of vitamin C (20 mg/100 g) was also rich with S. variolar...
This study was carried out to evaluate the quality of five marine fishes yellowfin tuna (Thunnus ... more This study was carried out to evaluate the quality of five marine fishes yellowfin tuna (Thunnus albacores, Bonnaterre, 1788), sailfish (Istiophorus platypterus, Shaw, 1792), slaya/sardine (Sardinella gibbosa, Bleeker, 1849), squid (Loligo duvaucelii, D' Orbigny, 1835) and shrimp (Fenneropenaeus indicus, H. Milne Edwards, 1837) based on total volatile base nitrogen test (TVB-N). The studied fish was collected from 19 commercial retail outlets in Sri Lanka in 2012, kept under ice and immediately transferred to laboratory for further analysis. The total volatile basic nitrogen (TVB-N) test was performed to assess the quality status of fresh fish. The limits of TVB-N for fishery products in Commission Regulation (EC) NO 2074/2005, which was ranged between 25 to 35 milligrams of nitrogen/ 100grams of fish flesh. The results of the present study revealed that base the total volatile base nitrogen (TVB-N) content, 5% of yellowfin tuna, 8% of sailfish, 12% of sardine, 100% of squids an...
Total mercury (T-Hg) concentration was measured in the hair of people who live and work in the Ne... more Total mercury (T-Hg) concentration was measured in the hair of people who live and work in the Negombo coastal area and Welimada mid country area of Sri Lanka. Hair samples were analysed for T-Hg by CVAAS (cold vapour atomic absorption spectrometry) in males (n= 52, 30 from Negombo and 22 from Welimada). Mean T-Hg level and ranged between 4.38±3.55 (>LOD-13.38) Negombo and 0.39±0.44 (>LOD-1.58) Welimada. The highest value was found in a 25 year businessman in Welimada (1.58 mg/kg), and the 28 years businessman from Negombo (13.38 mg/kg). All individuals from the Negombo area are consuming small fish to large fish ratio 1:1, and the common species are Trenched Sardines (Hurulla) and large fish like skipjack tuna (Balaya) yellowfin tuna (Kelawalla) and Treavallies (Paraw). But in some individuals in Welimada area are consuming small fish and the mean T-Hg was 0.29 mg/kg, while others have 0.67 mg/kg mean value. The 55.8% of the study population (13.6% Welimada& 86.7% Negombo) ex...