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Undergraduate Theses

Permanent URI for this collectionhttps://hdl.handle.net/20.500.14583/13

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    Fecundity and Oocyte size in the flyingfish (Cheilopogon arcticeps) from Lanuza Bay, Surigao Del Sur
    Belaza, Yeuclaire Dorothy M. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2018-06)
    The relationship of fecundity and oocyte diameter to body size and other reproductive aspects of the flying fish, Cheilopogon arcticeps in Lanuza Bay were investigated in this study. Gravimetric method or weight method was used in order to estimate the fecundity of 35 mature female C.arcticeps ranging from 17.8-23.6 cm standard length. Total fecundity of C.arcticeps ranged from 1,126 - 41,684 while its oocyte diameter ranged from 0.8 -3.6 mm. The relationship of fecundity to standard length (SL) showed variable results and poor correlation. This may be indicative of a unique reproductive strategy of this species. Egg size to standard length showed an increasing trend but a weak correlation. In general smaller egg diameters were observed in smaller size class SL and bigger egg diameters appear in larger SL. The relationship of fecundity to gonad weight showed a positive linear correlation and increasing data .Thus as gonad weight increases, fecundity increases too. The correlation between fecundity and total length shows a weak relationship, however the correlation between fecundity and gonad weight show a stronger relationship. The present study aim to exhibit additional information on the rare documentation of flyingfish in the country.
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    The degree of potency of emojis to substitute the written language in Facebook Messenger
    Bechayda, Kristelle Mae S.; Jaruda, Ma. Ella Dean R.; Pavillar, Gliza Mae D. (Division of Humanities, College of Arts and Sciences, University of the Philippines Visayas, 2018-04)
    This is an undergraduate study of how potent the emojis are in substituting the written language in Facebook Messenger. Purposive sampling was used in determining the 127 respondents in Iloilo National High School. Survey questionnaires were utilized in gathering the data. By using Kincaid's Convergence Model of Communication, Semiotics Theory and Uses and Gratification Theory, the researchers used descriptive method to analyze the potency of emojis by studying the respondent’s mutual understanding on their use of emojis. Mutual understanding is further determined by getting the individual field of experience of each respondent. The field of experience in this study includes the level of knowledge on the use of emojis, commonly used emojis, reasons why they use emojis and the capability of emojis in conveying messages. The findings of the study showed that emojis are highly potent in substituting the written language in Facebook Messenger.
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    Small farmers' adoption of rice combine harvesters in Binalbagan, Negros Occidental
    Bayona, Kate Ashley S.; Solano, Mirjana Antoinette (Division of Social Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2024-06)
    The use of Rice Combine Harvesters (RCH) is currently pushed as part of the country's mechanization program in agriculture. Much of the literature assessing the adoption of RCH only focuses on the tangible determinants of their adoption, but not the in-depth sociological lived experience of farmers following their adoption, including their nuanced rationalization amidst the process. This study investigated the RCH adoption among small farmers in Binalbagan, Negros Occidental, specifically delving into the (1) characteristics of farmers, (2) drivers of RCH adoption, (3) challenges faced during adoption, (4) nature of frequency and consistency of RCH use, and (5) adjustment strategies in using the RCH pursued through descriptive phenomenology and an in-depth interview of 12 participants through purposive sampling. Thematic analysis revealed that the small farmers belong to the early majority adopter category whose adoption is highly facilitated by membership in Irrigators’ Associations and lack of manual laborers. The regularity of their usage also depended on climate, laborers, topography, and farm systems and confronted issues with wastage, additional cost and labor, and field damage to RCH that was mitigated through mediating previous and current farm set ups and maintaining affirmative social relationships within the community. These findings depict the complexities in small fanners’ RCH adoption and the intricacies of their receptivity in each region calling for larger analysis of RCH adoption in the country to know its general status and underscores the need for the implementation and development of national policies like technology diffusion to be contextually sensitive and pro-farmers.
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    Optimization of parameters for the Fe-humic acid complex formation using cyclic voltammetry
    Bautista, Coleen M. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)
    Humic acid extracted from an artesian well located at Sta. Barbara, Iloilo was used to generate an Fe-HA complex as a potential additive to bio floc systems to augment the essential mineral Fe. The humic acid obtained was black in color and had a powdery texture after oven-drying. The Fe-HA complex were prepared using Fe3+ ions at different pH values specifically at pH 8, 9 and 10. Formation of the complex was investigated using the cyclic voltammetry to determine the ideal conditions to maximize the binding of the metal ion. The results showed that there are two oxidation and reduction cycles which suggests that there are two species undergoing oxidation and reduction. It is possible that the free iron and the Fe in the complex are undergoing a redox cycle although the quinone group in the humic acid can also act as a redox center. Atomic Absorption Spectroscopy can help corroborate the amount of complex formed to help deduce the redox active center.
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    Phytochemical screening, antibacterial and antioxidant activity of Ethanolic seed extract of Kadios (Cajanus cajan) from Igbaras, Iloilo, Philippines
    Bautista, Lance Ruther E. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2016-06)
    Natural products are products which may have been chemically synthesized, through semi- or total synthesis. The presence of these natural sources gave us greater opportunity for discovery and different innovations, as answers to the emerging needs of the people. This study focused on the chemical properties, antibacterial and antioxidant activity, of Cajanus cajan, popularly known as Kadios, from Igbaras, Iloilo, Philippines. A total of 371.98 grams of air-dried C. cajan seeds was macerated to 1000 mL of ethanol for 72 hours. The concentrated extract was subjected to three tests and assays. All tests were done in triplicates. The test for phytochemicals, which served as the preliminary screening, revealed that the ethanolic extract of Kadios seeds contains alkaloids, flavonoids, phenols, saponins, tannins, quinones, and steroids. The antibacterial assay showed that the ethanolic seed extract of C. cajan can inhibit the growth of Gram-negative bacteria, E. coli, with zone of inhibition equal to 10.3 ±2.15 mm to 33 ± 1.63 mm. The antioxidant assay revealed that the extract has positive inhibition only at high concentration against DPPH, and so IC50 was further determined to be 27,310 ug/mL. Statistical analyses were also done, and confirmed that there is significant difference among the data at (P<0.05). Summing up, the extract has antibacterial activity and minimal or almost close to zero antioxidant activity, while containing a remarkable number of secondary metabolites causing the chemical activities of the extract.
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    Antifungal activities of lemongrass (Cymbopogon citratus) essential oil -B-cyclodextrin inclusion complex incorporated in commercial fish feeds
    Baure, 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.
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    Hydrogel composites loaded with plant extract as an antibacterial and quorum sensing inhibiting wound dressing
    Baranda, Marivic M. (Division of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2018-06)
    Delayed wound healing is often caused by bacterial infection. Furthermore, the persistent inflammation brought by the formation of biofilm via quorum sensing causes pain and discomfort. In a novel effort, this study fabricated an antibacterial and quorum sensing inhibiting hydrogel dressing loaded with plant extracts. KC-PVP hydrogel composites were loaded separately with lg/mL C. longa and H. durvillei extract under optimized conditions. The hydrogels were characterized through swelling test and FTIR analysis. It was determined that C. longa-loaded and H. durvillei-loaded hydrogels have a maximum swelling capacity of 175% and 135%, respectively. The antibacterial efficacy and the quorum sensing inhibition activity of extract-loaded hydrogels were evaluated using soft-layer agar well diffusion method. Hydrogel loaded with C. longa extract displayed 47.0 (±1.0), 45.0 (±1.0), and 32.33 (±0.58) mm mean growth inhibition against S. aureus, E. coli, and P. aeruginosa, respectively. H. durvillei extract-loaded hydrogels inhibited the growth of S. aureus, E. coli, and P. aeruginosa by 45.33 (±0.58), 43.67 (±1.52), and 33.33 (±0.58) mm in diameter, respectively. The quorum-sensing inhibition zone of C. longa extract and H. durvillei extract-loaded hydrogels were 49.63 (±0.40) and 49.37 (±1.11) mm in diameter, respectively. Overall, the extract-loaded hydrogel composites exhibited good antibacterial and quorum-sensing inhibiting activity, potentially for wound treatment.
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    Phytochemical screening, antibacterial and antioxidant activities of the crude ethanolic extract of calamansi (Citrus microcarpa) peels
    Baquiano, Clarie Dean C. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2015-06)
    Citrus fruits are well-known sources of vitamin C, and like most other whole foods, they also contain an impressive list of other essential nutrients and high amounts of phytochemicals. Calamansi, scientifically known as Citrus microcarpa, is a native citrus plant cultivated throughout the Philippines. Calamansi is chiefly utilized for its pulp and juice but the peels and pressed pulp, covering each individual segment of the edible portion and seeds are considered as wastes and thrown away. To further utilize the rind or peels, this study was conducted to investigate the antioxidant and antibacterial properties of the crude ethanolic extract of C. microcarpa peels. Presence of select phytochemicals was also tested. The antioxidant and antibacterial activities were investigated using the DPPH (2,2-diphenyl-picrylhydrazyl) free radical scavenging assay and Kirby-Bauer disc diffusion susceptibility method, respectively. Results of the phytochemical screening have confirmed the presence of alkaloids, flavonoids, tannins, terpenoids, steroids and saponins in the extract. Crude ethanolic extract of C. microcarpa peels also showed activity against DPPH radicals with a half maximal inhibitory concentration (IC50) of 14.46 pL/mL, a much higher IC50 value compared to the positive control, ascorbic acid, with 8.36 pL/mL. The antibacterial activity assay of the extract showed minimal inhibition against E. coli and S. aureus.
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    Phytochemical screening, antioxidant activity, and comparative bioefficacy assessment of Camansi (Artocarpus camansi) seed extracts for in vitro antibacterial activity
    Bantayan, Andrea Marie B. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2016-06)
    This study was conducted to compare and assess the antibacterial and antioxidative properties, and to screen for the presence of phytochemical constituents in the different solvent-derived extracts of Artocarpus camansi seeds from Mintal, Davao City. Phytochemical analysis revealed the presence of alkaloids, flavonoids, glycosides, phenol, steroids, tannins, and terpenoids in the methanol extract. The antibacterial efficacy was determined by agar well diffusion method against B. subtilis and E. coli. Streptomycin was used as a standard drug for the study of antibacterial activity. Sensitivity in terms of zones of inhibition and phytochemical composition of the different extracts were also determined. Results showed that all extracts were effective against both of the bacteria tested with the pet. ether and DCM extracts showing moderate activity, and the methanol extract exhibiting strong activity against B. subtilis and E. coli. Furthermore, methanol extract of A. camansi seeds possessed strong DPPH radical scavenging activity. In the DPPH method, the pet. ether, DCM, and methanol extracts showed free radical inhibition of 18.96±0.16%, 21.62±0.14%, and 90.05±0.08%, respectively. The IC50 value obtained for the methanol seed extract at concentration 0.05 g/mL was 6.67±0.004 g/L. The current findings suggest that the phytochemicals present in the methanol extract of Artocarpus camansi seeds (alkaloids, flavonoids, glycosides, phenol, steroids, tannins, and terpenoids) may be responsible for the antibacterial and antioxidant activity.
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    Community structure of beach forest species in Mag-aba, Pandan, Antique
    Banogon, Tharrah Anne O. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)
    The Philippine beach forest is one of the understudied and less-popular important ecosystem that provides great number of food and economic products in the country. In fact, we lost them much earlier than the mangrove community that there is miniscule information is existing about them. There is a need for understanding the forest status and community structure due to the rising threats of natural and anthropogenic factors. The unexplored forest patch in Barangay Mag-aba, Pandan, Antique can provide additional information on beach forest diversity and abundance in the country, thus the need for this study. This study aimed to record the different species and to provide description of the community of beach forest in Mag-aba, Pandan. Specifically, the objectives of this study are (1) identify, describe and classify the beach forest species present in the area, and (2) describe the community structure in terms of species composition, diameter at breast height and stand height, stand basal area, importance value, evenness and Shannon- Weiner Index of Diversity. The transect plot method adopted from English et al (1994) was used to obtained quantitative data. A total of 80 beach forest species representing 41 families were recorded. The family Fabaceae and the species Cocos nucifera dominated the forest community. The stand basal area of 83.24 m2 ha-1 reflects a mature beach forest community, however the community is made up of mostly low DBH classes (saplings and seedling) also indicating a regenerating forest. Mag-aba is characterized to have a low species diversity (H'=1.17), however the individual species are fairly distributed (J'- 0.83). These results are addition to the existing knowledge of beach forest community that would serve as information for conservation measures.