Undergraduate Theses
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Item Antifungal activities of lemongrass (Cymbopogon citratus) essential oil -B-cyclodextrin inclusion complex incorporated in commercial fish feedsBaure, Jiaren G. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)During the wet season in the Philippines, fish feeds can be contaminated with mycotoxins, affecting fish production. The addition of essential oil (EO) is one of the ways to prevent this, but it is prone to physical and chemical reactions. Thus, this study aims to encapsulate lemongrass essential oil (LGEO) in B-cyclodextrin (B-CD) to produce an inclusion complex (IC) that can be used as an additive in commercial tilapia feeds to prevent or minimize fungal contamination. The inclusion complex was made using the co-precipitation method and was characterized by Fourier Transform Infrared (FTIR) Spectroscopy. The spectrum was similar to that of citral, a major component of lemongrass essential oil that is responsible for inhibiting fungi. The antifungal activities of pure and encapsulated LGEO at varying concentrations against Aspergillus species were carried out by the Agar Well Diffusion assay. Results showed that A. flavus was more susceptible in LGEO and IC compared with A. fumigatus. The tested concentration of EO could inhibit both fungi. However, it would take 50% IC to effectively inhibit the growth of both fungi. The stability of the inclusion complex in commercial fish feeds was also evaluated. The feeds were stored in an area with the appropriate conditions that could promote the growth of molds, such as temperature (>27°C), moisture levels (14%), and relative humidity levels (>70%). The results showed that the encapsulated LGEO was effective in extending the shelf life of the feeds and was best observed at a concentration of 5 g kg-1 IC. The oil remained active for nine days, wherein about 10- 40% of the feeds with 5 g kg-1 IC were covered with molds. On the other hand, about 70-100% of the surface of the feeds with essential oil was contaminated with molds after nine days, which indicated that encapsulation of EO was needed to maintain its effectiveness as an antifungal agent.Item A community study of mangroves in Brgy. Caliling, Cauayan, Negros OccidentalBarredo, Sherry Marie P. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2000-03)The species distribution of the mangrove community in Brgy. Caliling, Cauayanz Negros Occidental was studied using the transect line plot method with three plots for each of four stations established. Both stations 1 and 4 were located landward, while stations 2 and 3 were located seaward. Community structure Is described in terms of the following parameters; basal area, number of trees per hectare, importance value, relative density, relative frequency, frequency of species and relative dominance. Variations in these parameters are correlated with physico-chemical factors such as the air, water and soil temperature, water depth, salinity and pH. Ten true species were found In the mangals of the coastal environment of Brgy. Caliling, Cauayan, Negros Occidental. They were Avicennia aiba, Avicennia Janata, Avicennia manna, Campostemon phiiHpinensis, Excoecaria agallocha, Osbomia octodonta, Nipa fruticans, Brugeria cylindrica, Rhizophora apiculata and R. mucronata. Standard Basal Area was highest in Station 3 with 7.54 m/ha. In terms of zonation, the landward zone was found to have the highest Stand Basal Area with 11.15 m/ha. Station 2 had the highest density value of 33.92 %, whereas in terms of zonation, both the middle and seaward zone had the density value of 36.20 %. Avicennia marina was found to be the most dominant species and was observed to occupy sites with hypersaline conditions, in silty clay to muddy substratum, which may or may not be inundated by tidal flow most of the time.Item Historical analysis of Hippeatrum puniceum (Var) Lam.Bañas, Shirlyn L. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1996-03)A histochemical study Hipppeastrum puniceum, a bulbous plant of Family Amaryllidaceae, was performed to screen the plant for the presence of medically important substances that could be responsible for its curative powers. Results of the analyses showed that the leaf reacted positively to tests for presence of aldehydes, alkaloids, amygdalin, and arbutin; the roots tested positive for aldehydes, alkaloids, amygdalin, lecithin, oxalic acid, saponins, and tartaric acid. The bulb had aldehydes, alkaloids, amygdalin, arbutin, lecithin, saponins and tannins. On the other hand, the leaf, root, and bulb yielded negative results in the tests for presence of presence of citric acid, formic acid, lignin, and phytosterol.Item Determination of the fungal flora in the rearing water, eggs, larvae and post-larvae of Penaeus monodon in a large-scale hatchery systemBaes, Glanee F. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1995-03)The rearing water and homogenized. eggs, larvae, post-larvae of Penaeus monodon were taken front the large-scale hatchery system. These were counted, isolated and identified. Analysis was done by determining the mean, standard deviation and skewness of the data. The result showed that the skewness of the yeast and mold counts in the rearing water were 0.93 and 0.64, respectively 'while that in the homogenized samples were 0.92 and 1.09, respectively. These showed that the data were positively skewed, hence, fungi were greater in the early larval stages than in the later stages. The mean showed that yeast yielded greater counts as compared to the molds. Furthermore, rearing water have also higher fungal count than that of the homogenized prawns. The fungi identified were Aspergillus, Balanium, Bispora, Cladosporium and Phialomysis. In the study, the fungi identified were the normal mycoflora which did not adversely harm the prawn due to favorable hatchery conditions, there being no disease outbreak during the duration of the study.Item Taxonomy and distribution of holothurians in selected sites within Panabolon Island, GuimarasBachoco, Raian Dennis (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2001-04)This study mainly deals with the taxonomy and distribution of sub-tidal holothurians in 2 selected sites based on the predominant substrate and vegetation characteristics, within Panabolon Island. Sampling was done during low tides in the months of March and April 2001. A total of seven species in five genera belonging to families Synaptidae, Holothuriidae and Stichopodidae were recorded from the study area. The family Holothuriidae is the most common (4 species) of the three families. Synapta maculata is the most abundant species (33.33%) followed by Holothuria atra (27.27%) and Holothuria scabra (21.21%). Highest species diversity was observed in the coralline area with strong water movement while-densities are highest in areas with seagrass bedsItem Effect of soil amendments on damping-off disease of tomatoBalofiños, Junnel B. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1998-04)Different soil amendments obtained commercially were tested for their ability to suppress damping-off disease of tomato. Compost, animal manure, inorganic fertilizer, and green manure were applied to autoclaved soil prior to addition of a pathogenic inoculum. The biological control of the damping-off disease was evaluated by monitoring disease incidence in every plot of 50 seedlings for 25 days. Compost and animal manure significantly reduced disease incidence while green manure and inorganic fertilizer did not yield significant results as compared to the nonamended control soil. Percent emergence, dry matter content, and height were not at all affected by the different treatments.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 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 Integrating indigenous people's rights and development -oriented goals and interests in DRRM-CCA program: a case study of the Aeta community in Brgy.Mabuyong , Anini-y , AntiqueAlmendras, Denn Marie; Palomo, Megan; Tumaca, Jerald (2016-06)This study is about indigenous people's (IPs) rights and development-oriented goals. Specifically, it tackles on how their rights and goals are incorporated into Disaster Risk Reduction Management and Climate Change Adaptation (DRRM-CCA) plans and programs. The researchers chose the Aeta community of Barangay Mabuyong, Anini- y, Antique as research participants because it was able to fulfill the criteria of inclusion set by the researchers. They were also selected because they were affected by Typhoon Yolanda. The study used Mixed Methods to gather data. These consisted of keyinformant interviews, focused group discussions, secondary data analysis, surveys and transect walk. All these were deployed to gather data on the situation of the IPs in Mabuyong before and after Typhoon Yolanda in the following aspects: physico- environmental; econo-human; politico- institutional and;socio-cultural. The researchers also gathered information about the incorporation of IP interests, and the level of intervention of the LGUs in local DRR initiatives and development plans. Lastly, the researchers looked into the lessons learned after Typhoon Yolanda and surveyed the level of the community resilience, awareness, and response towards disaster.The findings revealed that: (a) the physico- environmental, econo-human, politico-institutional and socio-cultural contexts of the IP community are faced with a high level of vulnerability and risk exposure; (b) The incorporation of IP interests in the DRR and development programs revealed two contradicting views: The LGU's assessment was positive, and the incorporation of IP interests in policy and plans were present while the NGO and the IP community perceived such incorporation to be absent, insufficient and largely incompatible towards the IP needs; (c) Lastly, community awareness, resilience, and response of the IPs of Mabuyong were significantly low according to the survey. The study also found that the establishment of linkages among sectors and the active participation as well as reconciliation of the IPs in planning are necessary. The Typhoon Yolanda experience served as one proof that the IPs of Mabuyong needs more attention and assistance from the municipality.Item Heavy metal concentrations in sediments from Batan Bay and its tributariesAndrada, Mary Royce D. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2014-04)The concentration of three heavy metals (Cd, Pb, Cu) in sediments from Batan Bay and its tributaries were determined in order to assess the degree of contamination of sediments in the said area. The samples were digested following the Method 3050B of US Environmental Protection Program (EPA, 1996). The heavy metal concentrations were determined using Flame Atomic Absorption Spectrometer (FAAS). Results show that the heavy metal concentrations ranged from n.d. - 2.57 mg/kg dry weight (dw) for Cd; 16.44-143.02 mg/kg dw for Cu; and 3.18-28.53 mg/kg dw for Pb. Sediment sample collected from BTN #10 has the highest Cd concentration while sediment sample collected from BTN 052 which is a rice field in Batan, Aklan registered the highest Pb and Cu concentrations. Three sediment quality guidelines (National Oceanic and Atmospheric Administration, Canadian Sediment Quality Guideline and Hong Kong Sediment Quality Guideline) were employed to assess the metal contamination in sediments. The concentrations of Cd and Pb in all sites did not exceed the maximum permissible limits set by the three guidelines. As for Cu, BTN 052 exceeded the Upper Chemical Exceedance Level set by Hong Kong SQG. Correlation analysis showed that there is a significant correlation (p <0.01) between Pb and Cu indicating possible similar source input. Special attention must be given to BTN 052 since the levels of the studied heavy metals are high in this area. The results can be used as basis for the pollution level of sediments from Batan Bay and its tributaries. Special consideration should be given to BTN 052 since all of the test metals are significantly high in this area. It is also suggested to in identify the primary sources of metal contamination in this area.