Undergraduate Theses
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Item Effects of alginate coating loaded with lemongrass essential oil-cyclodextrin inclusion complex on the postharvest quality of calamansi(Citrus microcarpa)Astorga, Krizzia Anne B. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2018-06)Calamansi (Citrus microcarpa) is locally grown in the Philippines and is considered to be an important commodity because of its wide range of uses. Losses of this fruit in the country already reached up to 30% because of postharvest degradation. To address this problem, three coating treatments (1% alginate, 1% alginate loaded with lemongrass essential oil-B-cyclodextrin inclusion complex, and 1% alginate loaded with lemongrass essential oil-hp-B-cyclodextrin inclusion complex) were made for the purpose of examining their potential in the preservation of the postharvest quality of calamansi. Quality parameters such as color and weight loss of calamansi, as well as pH, FTIR spectra, total soluble solids, and titratable acidity of the fruit juice were evaluated in a span of 15 days at room temperature storage. Results show that the prepared edible coatings did not significantly preserve the postharvest quality of calamansi (p > 0.05) as coated samples resulted to earlier appearances of yellow and brown peel color, higher weight loss percentages, pH, and total soluble solids content. Out of the three coating treatments, fruit samples coated with 1% alginate resulted to lower weight loss percentages, pH, TSS, and TA. Fruit samples coated with 1% alginate loaded with lemongrass essential oil-hp-B-cyclodextrin inclusion complex resulted to the highest pH, TSS, and TA, while those coated with 1% alginate loaded with lemongrass essential oil-B-cyclodextrin inclusion complex resulted to the highest weight loss percentages. Data on the titratable acidity weren’t conclusive since the results obtained were not in agreement to the expected outcome. The ineffectiveness of the coatings may be a result of unfavorable storage conditions and incompatibility of the coating materials or formulations on the calamansi.Item Mud crab (Scylla serrata) shells for the removal of humic acids from Santa Barbara well waterAsdillo, Reina Jean A. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2010-04)The chemical contamination of drinking water from a wide range of contaminants such as humic acids can potentially lead to health-related in living organisms, especially humans. In rural areas of the Philippines, the use of low cost methods to remove water pollutants is, therefore, of great interest. In this study, osterized mud crab (Scylla serrata) shells or exoskeletons from cooked crab wastes were used to remove humic acids from the Santa Barbara well water. Adsorption experiments were done to evaluate its capacity to remove humic acids from the well water. Adsorption Isotherms and Fourier Transform Infrared Spectroscopy were employed to study the characteristics of the adsorption of humic acids onto the OSSE (osterized Scylla serrata exoskeletons). Adsorption experiments showed that at an average 1.0010 g of OSSE and after six hours of agitation, an average 74.95% of humic substances were removed from 50 mL of Montinola, Santa Barbara well water sample. Isotherm experiments showed that the experimental data can be fitted in both Langmuir and Freundlich models with low K values of 0.0235 L/mg and 0.4450 (mg/g)(L/mg), respectively. Based on the results of the above experiments, OSSE is a good adsorbent for humic acids in well waters (although more research need to be done on the removal of the substances remaining in the water after OSSE treatment) and the U-OSSE (used osterized Scylla serrata exoskeletons) can possibly be recycled.Item Preparation and characterization of chitin-humic acid hybrid and chitin-humic acid hybrid hydrogel as absorbent for Cu(II)Balgos, Blyth Angela C. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2017-06)Gelatinous chitin was functionalized with humic acid to produce a chitinhumic acid hybrid. The gelatinous chitin was protonated using HC1 and humic acid was deprotonated by using NaOH in separate containers. The protonated gelatinous chitin and the deprotonated humic acid were then mixed to form Hie chitin-humic acid hybrid. A portion of the chitin-humic acid hybrid was used to prepare the chitin-humic acid hydrogel. The chitin-humic acid hybrid hydrogel was then prepared using 1,2,3,4- butanetetracarboxylic dianhydride(BTCA) as crosslinker. The chitin-humic acid hybrid hydrogel was then characterized using FT-IR and swelling test. The degree of swelling of the chitin-humic acid hydrogel was found to be 38.10 ± 3.06. It can also be inferred from the results of the swelling test that the chitin-humic acid hybrid hydrogel has a low crosslink density. Characterization by FT-IR suggested successful immobilization for the hybrid and BTCA crosslinking for the hydrogel. The potential of chitin-humic acid hybrid and chitin-humic acid hybrid hydrogel to adsorb Cu(II) in a solution was then evaluated. The process was done by subjecting the chitin-humic acid hybrid to Cu(II) adsorption. The results for Cu(II) adsorption test was subjected to a Shapiro- Wilk test for normality and was determined to have normally distributed data. One- sample T-test was then used to compare the adsorption capacity of the hybrid and hydrogel. The mean % Cu(II) Removal of the chitin-humic acid hybrid and chitinhumic acid hybrid hydrogel were 41.36 ± 2.35% and 51.21 ± 1.32%, respectively. Results suggested that the chitin-humic acid hybrid hydrogel has significantly higher % Cu(II) Removal compared to the chitin-humic acid hybridItem Comparison of protein quality of three seaweed species (Sargasum polycystum, Sargasusum oligocystum and Ulva pertusa) from Panay and Guimaras Island, Philippines for potential use in milkfish feedArnaiz, Regina Marielle T. (Division of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2016-06)Aquafeed production is the largest expenditure in intensive aquaculture operations, contributing to about 40-60% of total costs (Yildrim et al., 2009; Akiyama et al., 1992 cited in Ali et al., 2009). This is mostly due to the ingredients being used, particularly the protein source fishmeal (Millamena, 2002). The variable and finite supple of fishmeal, however, result in high costs, prompting the search for cheaper alternative ingredients as a priority in cost reduction practices regarding the production of aquafeeds (Attala and Mikhail, 2008). Seaweeds have known nutritional values, and are naturally abundant in Philippine waters, thus their potential could be tapped to reduce costs in aquaculture and could therefore maintain the sustainability of the industry (Shields and Lupatsch, 2012; Trono, 1999). In this study, the protein quality of two brown seaweeds (Sargassum polycystum and Sargassum oligocystum) and one green seaweed (Ulva pertusa) was evaluated by determining their crude protein content, inhibitory activities against trypsin and chymotrypsin, and in vitro protein digestibility. Among the three species, the green seaweed U. pertusa has the highest crude protein content at 23.43%. The obtained crude protein content was 8.28% for S. polycystum and 9.22% for S. oligocystum. Trypsin inhibition of the seaweeds ranged from 54-57%, and chymotrypsin inhibition was from 57-64%. Total phenolic content (TPC) was highest in S. polycystum, and lowest in S. oligocystum. In vitro protein digestibility action of milkfish gut enzyme was highest in S. oligocystum (92.30 ± 2.80), followed by the observed digestibility in U. pertusa (75.01 ± 2.14), and lowest in S. polycystum (64.99 ± 8.11). Determination of Pearson's correlation (r) showed a negative correlation (r=-0.99, p=0.08) existing between the TPC and %RPD values. Based on the results, among the threes species, U. pertusa with 23.43% crude protein content and a %RPD of 75.01% has a potential for partial inclusion in aquafeeds to reduce costs.Item A novel water-in-oil-in-water emulsion to encapsulate antibacterial agentsBalcarcel, Angelica V. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2018-06)Encapsulating bioactive compounds can protect them from adverse conditions. This study aimed to encapsulate bioactive agents in a stable multiple emulsion system using a material that can be recovered easily from a product abundant here in the country. Results of the study revealed that the method of encapsulation used is effective in encapsulating and releasing the bioactive compound encapsulated. The antibacterial activity determination showed that encapsulated chlorhexidine is effective against both S. aureus and E. coli bacteria. Further investigation was made by encapsulating aqueous guava (Psidium guajava) extract in the same emulsion system (water-in-oil- in-water) using recovered coconut milk protein (CMP) as a gelling agent. The evaluation of the stability of the emulsions revealed that the treatment with 40% guava extract in the aqueous phase of its primary emulsion (Emulsion 3) is the most stable among the other treatments. This treatment showed the smallest droplet size range and most uniformed droplet sizes. The creaming index of this treatment also showed the lowest values after three (3) weeks of storage. On the other hand, the treatment with 60% guava extract in the aqueous phase of its primary emulsion (Emulsion 4) appeared to be the most stable against heating. However, no antibacterial activity was observed for any of the emulsion systems both S. aureus and E. coli bacteria. Additional test revealed that the bioactive compound present in the plant extract was disrupted by the sonication processItem A benchmark survey on the cyanide and protein content in the leaves and roots of cassava (Manihot esculenta Crantz) in IloiloBacolod, Hanny Joy C. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 2006-04)The cyanide and protein content of the roots and the leaves of the cassava samples were determined. Samples were taken from five locations, namely, Mambatad, Miagao; Poblacion, Lambunao; Ambarihon, Tubungan; Naclub, Miagao; and Calampitao, Miagao. This study shows the levels of cyanide and protein in the roots and leaves of the cassava samples from the five selected locations in the province of Iloilo only. It does not establish any concrete conclusion on the cyanide and protein content of the cassava in Iloilo. Based on the results, the amount of cyanide varies among parts of the plant with an average of 229 ppm in the leaves and 100 ppm in the roots. It also varies among varieties in the same location, the white root variety having 125 ppm cyanide in the roots and 202 ppm in the leaves, while the yellow root variety has an average of 58.2 ppm cyanide in the roots and 263 ppm in the leaves. Different locations also have different levels of cyanide. Cyanide content also decreases in the roots as the period of storage is prolonged. The level of cyanide in the white root variety from Lambunao decreased by 17.1% on the 2nd day and 61.5% on the 3rd day, while the yellow root variety, also from Lambunao, decreased by only 4.3% on the 2nd day and 30.1% on the third day. Total soluble protein in the leaves (0.12%) of the samples is higher than in the roots (0.11%) . Among the roots, the amount of protein varies. It was found out that there is a significant correlation (0.750 at 0.05 level) between the amount of protein in the roots and that in the leaves of the samples.Item Treatment of Vibrio harveyi-infected Penaeus monodon using Alibutbut (Tabernaemontana pandacaqui Poir.) plant powderBacaling, Marivic T. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 2005-04)The cytotoxicity test of crude methanolic leaf extract using Brine Shrimp Lethality Assay revealed that Alibutbut (Tabernaemontana pandacaqui Poir.) is safe to use in treating vibrio-infected penaeid shrimps. The effectiveness of the alibutbut powder against vibriosis was examined through the determination of the post-larvae 20 (PL 20) penaeid shrimp mortality and the water microbial assay after 48 hours. Percent penaied shrimp mortality (0-6.67%) and microbial count (2.91 x 10^4- 3.26 x 104 cfu/mL) of the plant treatments were significantly lower compared to the negative control (no treatment) that exhibited 50% penaeid shrimp mortality and a microbial count greater than 6.00 x 10^4 cfu/mL. The results of the experiment showed that Alibutbut plant powder is indeed effective in controlling Vibrio harveyi bacteria.Item Determination of heavy metal (Cu, Cd, and Pb) concentration in musclemeat of fish from different areas in Batan Bay, AklanBagarinao, Cathrina F. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2014-04)Food safety is of utmost importance but it is usually compromised by the presence of pollutants in the environment such as heavy metals. This study was conducted to investigate heavy metals concentrations in fish musclemeat collected from different areas of Batan Bay, Aklan. A total of 22 fish species were analyzed for Cu, Cd and Pb using Flame Atomic Absorbance Spectroscopy. Pb concentration in the musclemeat of fish ranged from 0.0292 ± 0.2070- 2.09 ±1.15 mg/kg wet weight and was found to be highest in Mugil cephalus (flathead grey mullet), while Cd concentration ranged from 0.0075 ± 0.0016-0.157 ± 0.209 mg/kg wet weight with highest value in Megalops cyprinoides (Indo-pacific tarpon), and Cu concentration ranged from 0.0605 ± 0.0667-2.76 ± 0.05 mg/kg wet weight, with highest concentration in Leiognathus equulus (common ponyfish). Among the metals, only Pb concentration in flathead grey mullet exceeded the maximum permissible concentration in food as indicated by the Joint FAO/WHO Codex Alimentarius (1984). Assessment of Noncarcinogenic Hazard Quotient (NHQ) gave NHQ values less than 1, indicating that the risk of developing adverse effects due to fish intake is low.Item Cytotoxicity and anti-vibriotic activity of Noni as an ethnobotanicalArrojo, Marley C. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 2005-12)The crude methanolic extract of Acacia, Alibutbut, Bayabas, Biab, Botolan, Bulobitu-un, Buyo, Kamunsil, Kasla, Kayos, Langka-langka, Noni, Pasaw, Sampaguita, Tabong, Talisay, Yellow bell, were bioassayed for their cytotoxicity using brine shrimp nauplii assay. Among the plant extracts, Noni gave the highest LCso equal to 943.329 pg/mL. Noni was the least toxic among the plants tested and its crude methanolic extract was found to have activity against V. harveyi with an anti-vibriotic index of 0.256. Sequential extraction using solvents with increasing polarity gave fractions that exhibited anti-vibriotic property but the more polar ethyl acetate fraction gave the highest anti-vibriotic index of 0.513. It appears that the anti-vibrio constituent is polar. Using VLC, the ethyl acetate fraction was further separated into eighteen fractions which were in turn pooled into five fractions, Fa, Fb, Fc, Fd, and Fe based on their TLC profile. Anti-vibriotic activity of each fraction was determined. Fraction Fa has the highest anti-vibriotic index (0.192) but this is much lower than 0.513. There must be some synergy among the polar constituents that exhibited a higher anti-vibriotic index in the ethyl acetate fraction compared to fraction Fa. Based on several color reactions, ethyl acetate fraction may contain any of the following plant metabolites such as tannins, saponins, phenolic groups, conjugated double bonds, flavonoids, sterols, terpenes, except alkaloids.Item Fourier transform -infrared-attenuated total reflectance spectroscopy in conjunction with the principal component analysis and agglomerative hierarchical clustering to classify virgin coconut oil and other edible oilsAloba, Eugene J. (Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas, 2006-04)This work investigates the potential of Fourier Transform Infrared-Attenuated Total Reflectance (FTIR-ATR) Spectroscopy in conjunction with Principal Component Analysis (PCA) and Agglomerative Hierarchical Clustering (AHC) to classify virgin coconut oil (VCO) from other different edible oils in the test set. Among the PCA types, Pearson produced the best biplot graphs that showed both the separation of VCO and coconut oil (only in one group) from other oils, and the separation of VCO and coconut oil (CCO) into two distinct groups using the fingerprint region of the spectra. Kendall dissimilarity/Ward’s method successfully clustered VCO and CCO as separate classes using the same region of the spectra. These results showed that the highest percent variability in the spectra of different oils occurs in the fingerprint region, and hence where spectroscopic classification of oils can be performed best.