DSpace Collection:

Biodiesel production from aquatic vegetation

2025-01-29T04:42:44Z

Title: Biodiesel production from aquatic vegetation Authors: Mercy, N.F.; Kapilan, R. Abstract: Biodiesel production from natural resources has drawn special focus due to its cost effectiveness, environmental friendliness and affordability compared to the environmentally challenging fossil fuels. The aquatic vegetation especially marine algae and weeds, is considered as the more secure, less competitive and express an exponential growth rate in their natural habit. They have the capacity to produce diverse waste supplements without much care, and most of the aquatic plants are not utilized for human food and animal feed. Biodiesel is produced by reacting lipids with alcohol that results in fatty acid esters. Transesterification and oil extraction are the two prime processes where diverse mechanical and chemical approaches involve. Transesterification reaction comprises of changing fatty oils into unsaturated fat alkyl esters, with alcohol and alkali catalyst with glycerol as a by-product. Oil is extracted by using solvents hexane, diethyl ether by soxhlet apparatus. Marine vegetational biomass can acquire lipids with in their cells like extracted oils from vegetables with a possibility to deliver multiple times more oil than some other terrestrial vegetation. Aquatic macro and microalgal and sea grass biomass can play a vital role in solving the issue of excessive energy demand for the increasing human population through their mass usage in the biodiesel production in the future and can help to fulfill the expectations, while decreasing the emission of greenhouse gases. Nonetheless, all the serious challenges should be successfully

A Comparative study on plasmid isolation from strains of Enterobacter aerogenes using different optimized procedures

2025-01-29T04:40:31Z

Title: A Comparative study on plasmid isolation from strains of Enterobacter aerogenes using different optimized procedures Authors: Gowri, R.; Kamalini, A.; Thavaranjit, A.C. Abstract: Enterobacter aerogenes are gram negative, facultative anaerobic motile bacteria which possess plasmids. Plasmids are extra chromosomal DNA. Plasmid DNA has been used as the most powerful tool in several molecular and biotechnological applications. In this current study three modified protocols were examined including mini preparation method, hot and cold alkaline lysis method and compared their simplicity, rapidity, costs and plasmid quality for extracting plasmid DNA from bacterial strains of Enterobacter aerogenes from different sources. According to the results obtained all three methods are good and yielded plasmid DNA but each methods has its advantages and disadvantages. Among all three methods, the spectrophotometric highest yield of plasmid DNA (83 ug/uL) was obtained in mini preparation method and lowest yield (20 ng/uL) in cold alkaline lysis method. The best spectrophotometric 260/280 ratio (near to 1.8) also obtained in mini preparation method which indicates the purity of extracted plasmid DNA. Among all three methods tested in this study, Mini preparation method is more efficient, time saving, non-hazardous and less cost method as it doesn’t require any expensive enzymes and hazardous chemicals.

Investigation of groundwater quality in “Kiramakodu area” of Point Pedro: Vadamarachi aquifer, Northern Sri Lanka

2025-01-29T04:21:59Z

Title: Investigation of groundwater quality in “Kiramakodu area” of Point Pedro: Vadamarachi aquifer, Northern Sri Lanka Authors: Velauthamurty, K.; Praveena, R.; Raagulan, K. Abstract: Water is one of the essential part for the existence of life on the earth crust. Over the past decades, demand for the potable water has significantly increased due to the deteriorating anthropogenic activity. Jaffna peninsula completely relies on the groundwater for all the purposes such as domestic, industrial and agriculture. The overpopulation destroyed the freshwater reservoirs and diminishes the natural potable source. This study focuses on a water quality parameters such as pH, turbidity, calcium, magnesium, chloride, sulphate, sodium, potassium, fat, oil and grease (FOG) in vaddamarachi aquifer and calcium (149.17-183.61 ppm), sodium (847.88-1222.99 ppm) and chloride (525.53- 924.80 ppm) content of most of the samples are higher than that of Sri Lankan standard for potable water. This study provides the basic information for the future medical study and gives awareness of water conservation in the region.

Effect of bacterial biofertilizers, native arbuscular mycorrhizal fungi and soil amendments on soil and grain phosphorus availability of flooded rice in dry zone, Sri Lanka

2025-01-29T04:18:08Z

Title: Effect of bacterial biofertilizers, native arbuscular mycorrhizal fungi and soil amendments on soil and grain phosphorus availability of flooded rice in dry zone, Sri Lanka Authors: Yapa, P.N.; Sandaruwan, M.K.D.D.; Duminda, D.M.S.; Bamunuarachchige, T.C. Abstract: Rice is considered as the most important food crop in Sri Lanka and most of the Asian countries. Over the past three decades, rice farmers have become increasingly dependent on synthetic chemical phosphorous fertilizers, mainly triple super phosphate (TSP) as a source of phosphorous (P). However, dramatically increasing costs, serious environmental and health issues attached to chemical fertilizers, forced researchers to develop supplementary or alternate sources of P for rice. Hence, this study was done to evaluate the potential use of biofertilizers and natural soil amendments as alternatives to chemical P fertilizers in rice (Oryza sativa L.) farming in the dry zone of Sri Lanka. A field trial was carried out at Ranpathwela in Anuradhapura, North Central Province, Sri Lanka, during the Yala season in 2016. The experiment was designed as follows: CON: control; AMF: AMF inoculants (2 Mg ha-1); RAMF: ERP (153.3 kg ha-1) with the AMF inoculants (2 Mg ha-1); MC: mixed microbial culture (5 kg ha-1); RMC: ERP (153.3 kg ha-1) with a mixed microbial culture [consortium of Azospirillum sp., Pseudomonas sp. and Bacillus sp. (5 L ha-1)]; BC: biochar (6 Mg ha-1); CP: standard compost (10 Mg ha-1) and IF: inorganic synthetic fertilizer (125 N kg ha-1, 62.5 P2O5 kg ha-1 and 50 K2O kg ha-1). Three indigenous and two improved rice varieties were used. The experiment comprised of 24 plots and three replicates. Soil, roots and grains of rice were analyzed for phosphorus. Some other elements were shown to have an effect on plant available soil P such as aluminum and iron, were also estimated. It was revealed that significant differences (p<0.05) in variety, treatment and V x T interaction was observed in plant available soil phosphorus. The highest mean of available soil P was observed in TRSP2 x AMF (14.64 ± 0.12 mg kg-1) followed by TRSP3 x MC (8.87 ± 0.001 mg kg-1) interactions. The multifunctional microbial consortium in amended soil, including Azospirillum sp., Pseudomonas sp. Bacillus sp. and arbuscular mycorrhizal fungi, were capable of potentially increasing soil phosphorus. Furthermore, the addition of rock phosphate did not always make a difference in soil P availability for rice farming systems.