Development of enrichment activities on antibacterial properties of Sampalok (Tamarindus Indica), Guava (Psidium Guajava) and Guyabano (Annona Muricata) / Marilyn D. Villaruel- Catanyag. 6

Thesis (M.A.)-- Pamantasan ng Lungsod ng Maynila, 1999.;A thesis presented to the Graduate School of Arts, Sciences, Education, and Nursing in partial fulfillment of the requirements for the degree of Master of Arts in Education major in Biological Science. 56

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ABSTRACT: The economic crisis besetting the country prompted the researcher to conceptualize an investigation on how indigenous resources could be utilized to produce antibiotic discs for Microbiology class. This aims to develop investigative skills and validate some findings of previous researchers through developing materials for enrichment activities that could stimulate the interest of the students and motivate them to search for other indigenous resources for investigations. This investigation was undertaken to find out: 1. Which plant extract with concentrations of 100%, 75% and 50% will exhibit the widest zone of inhibition? 2. Is there any significant difference between the performance of the leaf extract and the commercial antibiotics in terms of the diameter of zones of inhibition? 3. What enrichment activities can be developed from this investigation that could be utilized in Microbiology class? The conceptual framework of the study is designed to develop enrichment activities based on the experiments performed by the researcher. An experimental method of research was utilized to answer the research problems using the test organisms such as Staphylococcus aureus and Escherichia coli to determine the antibacterial property of the leaf extracts of selected plants like sampalok (Tamarindus indica), guava (Psidium guajava), and guyabano (Annona muricata). Purposive sampling was utilized for the selection of the leaves, test organisms, and solvents. This study utilized the instrumentation devised by Masilungan, et. al. (1955) to classify the growth inhibition (+++) which measures 5.0 millimeters and above, partial growth inhibition (++) which measures 3.0 mm to 4.9mm, slight growth inhibition (+) which measures 1.0mm to 2.9mm and no growth inhibition (0) which measures 0.0 mm to 0.99 mm. To compare the performance of the leaf extracts with commercial antibiotics, the One Way ANOVA was applied where the mean zones of inhibition were utilized in the computations. The following findings were derived from this investigation: 1. The plant extract that exhibited the widest zone of inhibition is the 100% P. Guajava leaf extract with 95% ethyl alcohol as the solvent. 2. The 100% P. guajava alcoholic leaf extract exhibited complete growth inhibition which were also exhibited by the four antibiotics used. From the aforementioned findings of this study, enrichment activities for Microbiology class can be developed. They are as follows: Activity No. 1. Preparation of Leaf Extracts 2. Preparing and Dispersing Media 3. Preparation of Inoculums and Culture Transfer 4. Inoculation of Bacterial using Streak and Pour Plate Techniques 5. Antibiotic Sensitivity Testing 6. Preparation of Bacterial Smear for Staining 7. The Gram Staining Technique 8. Classification of Microbes in the Environment 9. Isolation of a Pure Culture From the findings of this study, the following conclusions were drawn are: 1. The plant extract that showed the widest mean zone of growth inhibition on S. aureus is the 100% guava alcoholic leaf extract. 2. The performance of the leaf extract is comparable to commercial antibiotics since there is no significant difference between their zones of growth inhibitions. 3. Enrichment activities could be developed based on this investigations for utilization in a Microbiology class in the tertiary level. The following are recommendations based on the findings of this study: 1. Other indigenous resources be studies for their antibacterial property with the following variations: a. Use different solvents and concentrations b. Use other parts of the plants c. Use other test organisms 1. Compare results of the experiments on other indigenous resources with other commercial antibiotics. 2. Replicate the prepared enrichment activities and perform in a Microbiology class. 3. Science supervisor should design for seminars and workshops considering the availability of their resources to replicate this study.

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