STUDENT RESEARCHES

The student researches highlighted in this site have participated in at least one national research congress/fair.

 

Title:

PHYTOCHEMICAL SCREENING, NUTRIENT ANALYSIS AND ANTIMICROBIAL ASSAY OF BARANGBANG FERN (Stenochlaena palustris)

  (PSHS-CVC official entry to the 1st Philippine International Science Fair, February 2-6, 2013, Antipolo City)
Date of Submission to PSHS:
March 2013
Researchers: Claire Isabelle R. Foronda, Rizza Francesca B. Noscal and Naomi Renee Dominique B. Salagubang
Research Adviser:
Julius A. Garcia
Research Teacher: Genalyn Alice R. Viloria
ABSTRACT

     Stenochlaena palustris, locally called Barangbang, is a common vegetable in Northern Luzon (Philippines) yet little is recognized about its phytochemical and nutrient characteristics and its antimicrobial properties. Thus, this study delved into the phytochemical and nutrient screening of this plant and in the in vitro determination of its antimicrobial potential in the hope of discovering its possible medicinal uses. Phytochemical screening of S. palustris further revealed that it contained flavonoids, tannins and anthraquinones which are known to exhibit antioxidant, anti-inflammatory as well as antimicrobial properties supporting the researchers' theory that this plant has high antimicrobial potential. Nutrient analysis of S. palustris following Official Methods of Analysis (DOST RO2) showed that the plant contains 37.46% carbohydrates, 35.93% proteins and 1.39% fat proving further that it is a healthy source of carbohydrates and proteins. Antimicrobial assays of S. palustris revealed that it is effective in inhibiting the growth of the Gram-negative bacteria E. coli, P. aeroginosa and S. enterica as well as of the Gram-positive bacteria S. aureus, B. cereus, E. faecalis, but not as statistically effective as Cephalexin, although S. palustris was statistically much more effective than Cephalexin in inhibiting E. coli growth. S. palustris was also found to be an effective antifungal agent against C. albicans. However, it was not found to be as statistically effective as 2% ketoconazole. The plant, however, was found to be inactive against E. aerogenes. S. palustris, having found to be an effective antimicrobial agent against a broad spectrum of human pathogens, is highly recommended for future extensive studies and development into useful health and medicinal products.

 

Title:

IN VITRO ANTIMICROBIAL EFFECTS OF Mimosa pigra EXTRACT ON BLAST (Pyricularia oryzae) AND BACTERIAL LEAF BLIGHT (Xanthomonas oryzae) OF RICE (Oryza sativa L.)

  (PSHS-CVC official entry to the 1st Philippine International Science Fair, February 2-6, 2013, Antipolo City)
Date of Submission to PSHS:
March 2013
Researchers: Rhanella H. Medina, Trissia Marie B. Ordoñez, and Joseph Timothy S. Sana
Research Adviser:
Gaudencio M. Natividad, Ph.D.
Research Consultant:
Jonar I. Yago, Ph.D., Nueva Vizcaya State University
Research Teacher: Genalyn Alice R. Viloria
ABSTRACT

     The study evaluated the anti-microbial activity of Mimosa pigra extract against two major diseases of rice: bacterial leaf blight (Xanthomonas oryzae) and rice blast (Pyricularia oryzae). Shoots of Mimosa pigra were air-dried and ground and a total of 180 grams of ground samples were gathered and soaked in 540 mL of ethanol for one week. The mixture was filtered and the filtrate was subjected to rotary evaporation.  After evaporation, 250 mL of the extract was produced and kept under room temperature in an Erlenmeyer flask. Phytochemical analysis was conducted to determine the presence of active compounds in the extract. Antimicrobial assay was then carried out through filter paper-disc method using appropriate media and pure culture of the two diseases. The Frothing and Liebermann-Burchard tests revealed the presence of saponins and steroids respectively. The other tests indicated absence of alkaloids, flavonoids, glycosides, and tannins. The antimicrobial test for bacterial leaf blight indicated strong effects of both Mimosa pigra extract and the positive control, Funguran, with a relative magnitude of inhibition of 5.84 mm2 and 18.39 mm2, respectively. The negative control treatment (sterile distilled water) had zero value for the parameter. For rice blast, both M. pigra and the positive control were effective in inhibiting mycelial growth of the pathogen with mean diameter values of 27 mm and 21 mm respectively. The negative control did not inhibit mycelial growth giving the highest diameter mean value of 43.5 mm.The study concludes that M. pigra extract possess active phytochemicals that can be effective against bacterial leaf blight and rice blast. Further investigation should be done using more replicates and more samples for measurement to get more conclusive results. The extract can be fractionated using other solvents like methanol and chloroform to isolate other active phytochemicals from the extract. Thin layer chromatography can also be done to get the active compounds prior to possible in vivo testing against the two pathogens.

 

Title:

EFFECT OF CHITOSAN FROM THE EXOSKELETON OF THE AMERICANA COCKROACH (Periplaneta americana) ON THE CLOTTING TIME OF HUMAN BLOOD

  (Champion in the Regional Level DepEd-Intel Philippine Science Fair and Science Quest for Secondary Level – Cluster II – Life Sciences, Team, November 12-14, 2008, Cabarroguis, Quirino; PSHS-CVC and Region 02 entry to the DepEd-Intel Philippine Science Fair 2009)
Date of Submission to PSHS:
March 2009
Researchers: Pauline Carol L. Calma, Jennalyn A. Fider, Carmine Sarah C. Onza
Research Adviser/Teacher:
Sadiri S. Corpuz
ABSTRACT

     Coagulants are often used to stop wounds from bleeding at a faster rate preventing the occurrence of infection. Some commercial coagulants include chitosan as one of its components. The aim of this research was to test if chitosan from the exoskeleton of cultured house cockroach also known as the American cockroach (Periplaneta americana) hastens the clotting of human blood, specifically, Type O blood. Chitosan was extracted from the exoskeleton of cultured P. Americana following the procedure used in a similar project by MMAENGA in Netherlands. Three replicates of seven different setups of 0.20 mL of pure blood were treated with varying amounts of chitosan and ferric sulphate (Positive Control). The blood clotting time in each treatment was monitored using the applicator stick method wherein the time (in seconds) it took for the fibrin to form starting from the time blood was extracted from donors was measured. Data analysis at a 0.05 level of significance showed that the clotting time of blood treated with chitosan and that of blood treated with ferric sulphate are significantly lower than that of untreated blood at different amounts (10, 15 and 20 g) of each treatment. No significant differences were observed between the clotting times of chitosan- and ferric sulphate-treated blood at all treatment amounts. On the light of the findings of the study, chitosan, therefore, hastens the clotting time of Type O human blood, and as a coagulant, it is as effective as ferric sulphate. Moreover, varying the amounts of chitosan and ferric sulphate applied on the blood samples yields the same effect on the clotting time of Type O human blood. To make this research more extensive, it is recommended that the effect of chitosan on the clotting time of other blood types (A, B, AB) be studied. Furthermore, the use of chitosan extracted from other animal exoskeletons like that of shrimps is also recommended for future research. The results of all these studies may also be verified using other accurate and sophisticated instruments for measuring blood clotting times.

 

Title:

ANTIMICROBIAL EFFECTS OF MAHOGANY (Swietenia macrophylla King) SEED OIL ON GREEN MOLDS (Penicillium digitatum) IN PONKAN MANDARIN (Citrus reticulata Blanco) FRUITS

  (Champion in the Regional Level DepEd-Intel Philippine Science Fair and Science Quest for Secondary Level – Cluster II – Physical Sciences, Team, November 12-14, 2008, Cabarroguis, Quirino; PSHS-CVC and Region 02 entry to the DepEd-Intel Philippine Science Fair 2009)
Date of Submission to PSHS:
March 2009
Researchers: Lugienor Lucille DR. Roberto, Dana Louise R. Soriano
Research Adviser:
Genalyn Alice R. Viloria
Research Consultant:
Jonar I. Yago, Ph.D., Nueva Vizcaya State University
Research Teacher: Wowee Rey P. Ariza
ABSTRACT

     In the Philippines, citrus fruits are propagated as a source of income. However, citrus production is threatened by diseases like green molds (Penicillium digitatum). Hence, this study was done to find a way to eliminate, if not, reduce the occurrence of green molds. The foremost aim of this study is to determine the antimicrobial effects of mahogany (Swietenia macrophylla King) seed oil against green molds both (1) in vitro using radial growth assay in Potato Dextrose Agar (PDA) and (2) in vivo as a coating on harvested citrus fruits, specifically, Ponkan Mandarin (Citrus reticulata Blanco). The oil was extracted from homogenized seeds of mahogany through heating at different durations, particularly, 60 min (Treatment A) and 60 min (Treatment B). Distilled water as used as a blank treatment or negative control (Treatment C) and Copper oxychloride was used as the positive control (Treatment D). All observations were obtained from three independent replicates. It was found that heating the homogenized mahogany seeds for 60 min produced a higher percent yield of oil that is darker and is slightly less dense than when heating it for 40 min. There are significant differences in the mean radial growth of green molds after 64 h in Treatment C (30.1 mm) and those of Treatments A, B and D (1.8 mm, 4.4 mm, and 0 mm, respectively) which are statistically equal. On the other hand, citrus fruits applied with Treatment A showed significantly greater Visual Quality Rating and Peel Color Index than Treatment D (Copper oxychloride) but showed statistically equal Disease Severity Index compared to the same. These findings prove that mahogany seed oil is an effective antimicrobial agent against green molds based on both in vitro and in vivo assay results. Furthermore, it is more effective when obtained at a longer heating duration (60 min) than at a shorter heating time (40 min). With mahogany seed oil showing much promise as an antimicrobial agent against green molds, it is; thus, recommended for future studies and entrepreneurial endeavors.