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Undergraduate Theses

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    Comparative study of trace metals and common impurities of table salt produced in Leganes, Iloilo and Tibiao, Antique
    Calawag, Jerolet E. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 2000-10)
    Trace metals such as cadmium (Cd), chromium (Cr) and lead (Pb) as well as the common impurities in salt like magnesium (Mg), calcium (Ca), sulfate, moisture, matter insoluble in water (MIW) and matter insoluble in acid (MIA) were analyzed using spectrophotometric (Flame Atomic Absorption &UV-vis Spectrophotometers) and gravimetric methods. Results showed that percentage concentrations of magnesium and calcium were significantly higher in sample A (Tibiao table salt) than in sample B (Leganes table salt) at 1- percent level of confidence. The percentage concentrations of MIW, MIA, moisture and sulfate were significantly higher in sample B than in sample A. Results of Uv-vis absorption spectroscopy indicated that both chromium and cadmium were absent in both samples while the lead concentrations in samples A and B were 10.9190 and 11.4831 ppm respectively. At 5% level of probability, the lead concentrations of both samples did not differ from each other. Using another technique of analyzing trace metals, the flame atomic absorption spectroscopy based on flame atomization, different results were obtained. Lead concentration in samples A and B were 6.4874 and 9.4977-ppm salt respectively. At 5 % level of probability, sample B had higher lead concentration than in sample A. The lead concentrations in both samples were all higher than 0.015 ppm, the allowable maximum limit of lead in water, or any drinks. The over-all results showed that sample B had higher contaminants than in sample A.
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    A preliminary study on the average yield of crude capsaicin from common varieties of Capsicum frutescens L. at two stages (Young and mature) using three extracting solvent
    Cadornigara, Ma. Sylvia C. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 1998)
    Crude capsaicin content of the air dried and homogenized plant material of the three varieties of Capsicum frutescens L. namely cayenne, tobasco and ‘kitikot’ were determined using diethyl ether, 99.5 % ethanol and 1.0N NaOH as extracting reagents. Statistical analysis showed no significant difference on the average percent yield of crude capsaicin on the three varieties of Capsicum frutescens L. using similar extracting solvent, but a significantly higher yield of crude capsaicin was found with 99.5% ethanol and 1.0N NaOH. Through thin layer chromatography the major components of the extracts identified could probably be capsaicinoids (Rf 15-17), carotenoids (only in 99.5% ethanol, Rf 96-97), and capsanthin (Rf 27-29) using n-hexane-acetone.