These are albums uploaded to the (unofficial) facebook page ( of the PSHS-CVC Documentation Committee.

Please click the links below to view these albums.

SY 2016-2017

2016-08-01 Opening Program & Orientation

2016-08-01 Mass of the Holy Spirit

SY 2015-2016

2016-06-22 GAD Seminar Bohol

17th Recognition Day

2016-05-20 RecogDay Mass

2016-05-20 (A) RecogDay Entrance

2016-05-20 (B) Recog Day Special Citations

2016-05-20 (C) Recog Day Director's Listers

Family Day 2016

2016-04-30 Pisay FamRun A

2016-04-30 Pisay FamRun B

2016-04-30 Family Day A

2016-04-30 Family Day B

2016-04-30 Family Day C

2016-04-28_29 Procurement Seminar

2016-03-09 ALA Arts Month Celebration

2016-03-18 3rd Quarter Card Giving Day

2016-02-19 PSHS-CVC Orientation Program for NCE Passers

2016-02-16 Pisay-CVC Hug Day

2016-02-11 Teachers and Staff Medical Exam

2016-02-05 MTAP Division Finals

2016-02-03 Visit of PSHS BOT Member Dr. Guevara

2016-01-15 2nd Card Giving Day

2016-01-22 Financial Planning 101

Fusion (Science, Math, Science, and Technology) Days 2016

2016-01-28 Fusion Mass

2016-01-28 Fusion Program

2016-01-28 Style Wars Illuminance (Pics Grp A)

2016-01-28 Style Wars Illuminance (Pics Grp B)

2016-01-25 Sir Buddy's BDay Celebration

2016-01-16 Division Math Fest

2016-01-07 PSHS-CVC Recital

2015-12-18 Pisay Teachers&Staff Christmas Party

Gender and Development Activity (Subic, Zambales)

2015-12-15 GAD Subic Seminar

2015-12-15 GAD Subic Day 1 PM Games

2015-12-15 GAD Subic Fellowship Night

2015-12-16 GAD Subic Day 2 AM Volleyball

2015-12-06 PSHS GAD Activity Day2 PM Basketball and Awarding

2012-12-11 Christmas Photos

2015-12-11 Pisay Christmas School Program

2015-11-29 PSHS-CVC Leadership Training

Miss United Nations 2015

2015-11-06 Miss UN Pageant Preps

2015-11-06 Mr & Miss UN (Costume, Uniform)

Intramurals 2015

2015-10-28 Pre-Intrams

2015-11-05 A Intrams Parade & Opening Program

2015-11-05 B Intrams Day 1 AM Games

2015-11-05 B Intrams Day 1 PM Games and UN Stage Preps

2015-11-06 Intrams Day 2A

2015-11-06 Intrams Day 2B

2015-10-16 PSHS-CVC 1st Card Giving Day

Gender and Development Activity (Davao City)

2015-10-07 Davao Day1 A Travel and Pisay SMC

2015-10-07 Davao Day1 B Benchmarking at Pisay-SMC

2015-10-08 GAD and Leadership

2015-10-08 Day2 B Aldevinco Jacks Ridge

2015-10-09 Day3 A Cathedral City Hall ALU Hotel

2015-10-09 Garden of Eden Restored (Prayer Mountain)

2015-10-03 Sn Mateo Training on Conduct of Investigatory Projects

Pisay-CVC Quiz Show 2015

2015-09-12 Pisay-CVC Quiz Show Cauayan Division

2015-09-12 Pisay-CVC QuizShow Divisions of Tuguegarao and Cagayan

2015-09-19 PisayCVC QuizShow Grand Finals

2015-08-18 Welcome Freshmen

2015-08-17 Recollection Grade 9

2015-08-14 DBServer Reorientation

2015-08-07 Bayombong Town Fiesta

2015-07-28 Miting de Abanse

2015-07-24 Fire and Earthquake Drill

2015-07-20 First Day of the School Year

Gender and Development Activity (Baguio City)

2015-07-13 GAD Seminar Day 1 (Travel & Fellowship Night)

2015-07-14 GAD Seminar Day 2 (Gender Sensitivity Seminar-Workshop

2015-07-15 GAD Day 3 AM (Sportsfest)

2015-07-15 GAD Day 3 PM (Sportsfest)

Headstart for SY 2015-2016

2015-07-01, 03 Headstart w/ the CISD, SSD, FAD & Campus Director

2015-07-06 Headstart Leadership Seminar ReEcho

2015-07-07 Headstart PASCO Seminar

SY 2014-2015

2014-09-26 1st Card-Giving Day

2014-09-21 Pisay-CVC Quiz Show Grand Finals

2014-09-13 Pisay-CVC Quiz Show Division Eliminations Cagayan

2014-09-13 Pisay-CVC Quiz Show Division Eliminations Cauayan City


2014-09-06 Intramurals Day 2 PM

2014-09-06 Intramurals Day 2 PM Cheerdance

2014-09-06 Intramurals Day 2 AM

2014-09-05 Intramurals Day 1 PM

2014-09-05 Intramurals Day 1 AM

2014-07-11 Anti-Bullying Seminar

2014-07-05 PSHS-CVC Alumnight Group Pics

2014-07-05 Alumnight (Pics Grp 1)

2014-07-05 Medical Mission

2014-07-03 18th Foundation Day D - Basket and Volley

2014-07-03 18th Foundation Day C - Program

2014-07-03 18th Foundation Day B-Mass & Blessing

2014-07-03 18th Foundation Day A-Motorcade

2014-06-27 Welcome Grade 7

2014-06-24 Fire Drill

2014-06-26 First Day High




Chemistry/Environmental Science

Researchers: Bryan C. Alpecho
Adrian B. Bayle
Czar Enrico B. Salvador
Research Teacher:
Genalyn Alice R. Viloria
Research Adviser: Maria Cristina C. Valeros

Water toxicity to living organisms is of great concern as today’s potable water levels are rapidly decreasing. Decreasing the concentrations of heavy metals in water through biosorption was explored. Saccharomyces cerevisiae was used as a biosorption agent to remediate different heavy metal ions in simulated heavy-metal polluted ground water. Briefly, 20 mL of aqueous solutions with critical concentrations of heavy metal ions namely 0.025 ppm Ni(NO3)2, 1.3 ppm Cu(NO3)2 and 0.5 ppm FeCl3 were added with 5 mL of S. cerevisiae solutions in PDB (McFarland Standard 10) at different concentrations (1 mL, 2 mL, and 3 ml S. cerevisiae in 4 mL, 3 mL and 2 mL distilled H2O, respectively). All treatments were conducted under constant conditions such as temperature and agitation period. After a week, results showed that S. cerevisiae had a significant remediating capability for Ni (II), Cu (II), and Fe (III). The average percentage of removal are as follows: 41.89%, 74.51%, and 29.30% for Ni (II), Cu (II), and Fe (III) ions, respectively. It is found that S. cerevisiae is highly effective in reducing the concentrations of the said metal ions based on the Analysis of Variance at 0.05 alpha.

Biochemistry/Health and Medicine

Researchers: Jayson L. Cubalit
Junnarose M. Purisima
Mikhaela Mari Tambaoan
Research Teacher:
Genalyn Alice R. Viloria
Research Advisers: Catherine Joy A. Addauan, Melanie A. Mejia

The study was conducted to evaluate the antimicrobial effect of the Acid Solubilized Collagen (ASC) of Oreochromis niloticus (Nile Tilapia) scales against Staphylococcus aureus. Air dried tilapia fish scales were extracted for collagen initially with 0.1 M of NaOH to remove the base soluble substances then with 10% (v/v) butyl alcohol to remove the fat tissues finally with 0.5 M acetic acid to acquire the solubilized collagen with a yield of 22.40%. Antimicrobial assay was then carried out through Agar diffusion.

The antimicrobial effect was based on the zone of inhibition measured in mm and the result were analyzed and compared using One-Way ANOVA of the Statistical Packages for Social Science 16 (SPSS) at a 0.05 level of significance. The mean zone of inhibition of the Acid Solubilized Collagen (ASC) falls in the 13mm-19mm range. This indicates that Nile tilapia scale collagen is active against S. aureus. Also, the positive control exceeding having the mean zone of inhibition of 39.97mm which exceeds 19 mm is very active against S. aureus. The positive control is significantly more active than the Nile tilapia collagen. The blank setup and negative control, water and acetic acid respectively, had no activity at all. These results prove that Nile tilapia scales are potential source of collagen and Acid Solubilized Collagen (ASC) of Nile tilapia scale is a potential antimicrobial agent.

Health and Medicine

Title: EFFECT OF Pleurotus ostreatus (Oyster Mushroom) ON THE BLOOD PLATELET COUNT OF Mus musculus (Swiss Albino Mice)
Researchers: Vallerie Joy P. Bico
Regina Lianne N. Carganillo
Rachelle A. Carlos
Research Teacher:
Catherine Joy A. Addauan
Research Adviser: Julius A. Garcia

Pleurotus ostreatus, commonly known as Oyster Mushroom, contains nutrients that are essential in increasing blood platelet count. This study aims to determine the effect of varying concentrations of Pleurotus ostreatus on the blood platelet count of Mus musculus. The Pleurotus ostreatus extract was administered to the mice through intraperitoneal administration then blood samples were collected in different time interventions. Statistics showed significant effect on the blood platelet count of Mus musculus per treatment using paired-samples t-test and no significant effect (at p<0.05) using one-way ANOVA, thus, this study concludes that Pleurotus ostreatus possesses no anti–thrombocytopenic potential.


Researcher: John Paolo A. Lumanlan
Research Teacher:
Ronald M. Navalta
Research Adviser: Jenshiam E. Balgua

The research entitled “Development of a Semi-Social Networking Site for the S.C.A.L.E. Program of the Philippine Science High School – Cagayan Valley Campus” dealt with the integration of technology to the documentations and the S.C.A.L.E. achievements of the student included in the program. The program extends the services from the processing the research document to the presentation of the achievement. The program was built and developed through the adaptation of the System Development Cycle. It was proven to provide efficient service to the clienteles of the S.C.A.L.E program.

Amended Guidelines on Promotion, Probation and Graduation of PSHS Students

I. Rationale

The Revised Guidelines on Promotion, Probation and Graduation of PSHS Students, which was approved by the PSHSS Board of Trustees in May 9, 2003, is hereby amended to better ensure quality standards in evaluating and assessing student performance. The amendments shall also be a step to further harmonize the academic standards throughout the PSHS campuses nationwide and foster a greater understanding by the students of the rules and regulations governing their scholarship status.

II. Policy

The desired characteristics of the PSHS scholar, as mentioned in the PSHS Vision, "...scientific mind, passion for excellence, dedicated to the service of country, and committed to the pursuit of truth", if to be molded in the character of the scholars with the help of the school, the faculty and staff have to have nurturing characteristics themselves, and the school shall have programs that will see to it that the students fully develop their potential and become responsible citizens of the country and leaders for the future.

Needs of individual students differ, thus a well–rounded curriculum as well as various programs will have to be in place to address these needs. Once these programs are in place, and the students are given every opportunity to adjust to the rigorous requirements for the scholarship provided them, the scholars are thus expected to perform according to expectations, both academically and behaviorally.

III. Guidelines
1. Good Standing

1.1 A student is in good standing for the incoming school year if s/he meets the minimum academic and disciplinary standards in the precious year, namely:

  1. s/he receives a final GWA of 2.25 or better;
  2. s/he has no failing grade of 5.00 in any subject in the final quarter of the school year; and
  3. s/he incurs three (3) or less unexcused days of absences.
2. Probationary Status

2.1 A student will be on probationary status for the incoming school year:

  1. if s/he receives a final GWA of 2.25; or
  2. if s/he has committed a major offense (at least Level III offense); or
  3. if s/he incurs at least eight (8) days of unexcused absences.

2.2 A student on probationary status is not allowed to be an officer in any school organization and shall not be allowed to represent the school in competitions.

3. Termination of Scholarship

3.1 Termination of scholarship means that the scholarship contract shall be unilaterally rescinded due to the student's failure to comply with a particular provision in the contract.

3.2 A Grade 7–11/First to Third Year student shall be recommended for termination of her/his scholarship:

  1. if s/he receives a failing grade of 5.00 in any subject in the final quarter of the schoolyear; or
  2. if s/he incurs thirteen (13) or more unexcused absences; or
  3. if s/he has committed two (2) major offenses (at least Level III offense) within the school year; or
  4. if s/he incurs two (2) successive probationary status.
4. Graduation of Students

4.1 A student in her/his final academic year at the PSHS is eligible for graduation if s/he meets the scholarship policy requirements on the following:

  1. academic performance
  2. conduct; and
  3. attendance
5. Ineligibility for Graduation of Students

5.1 A student who fails to graduate shall not be issued a diploma as proof of her/his graduation.

5.2 A student in her/his final academic year at the PSHS shall not be eligible to graduate should any of the following conditions be present:

  1. if s/he receives a failing grade of 5.00 in any subject in the final quarter of the school year; or
  2. if s/he incurs thirteen (13) or more unexcused absences; or
  3. if s/he has committed two (2) major offenses (at least Level III offense) within the school year.
6. Implementation

The resolutions of the Campus Scholarship and the Management Committees for cases related to guidelines 1 and 2 above are immediately implementable. For cases pertaining to guidelines 3, 4 and 5, the Executive Committee reviews and recommends resolutions to the Board of Trustees for the latter's final decision.

7. Separability Clause

If for any reason, any provision of these guidelines is declared invalid or unconstitutional, the other parts not affected will continue to be in full force and effect.

8. Repealing Clause

All previous issuances inconsistent herewith are deemed amended accordingly.

9. Effectivity

This set of guidelines shall take effect within 15 days following publication in the Official Gazette of the Office of the National Administrative Register (ONAR) of the UP Law Center, or in two newspapers of general circulation, and shall henceforth be known as "Guidelines on Promotion, Probation, and Graduation of PSHS Student".

Health and Medicine

(First Place, PSHS–CVC Local Science Fair — Health and Medicine Category; Qualifiers: PSHS System–wide Science Research Summit 2014; Champion, 9th Zonal High School Thesis Competition, Central Luzon State University)
Researchers: Agbayani, Daniella L.
Alba Alyssa Joselle B.
Guzman, Junel Christine B.
Dr. Sonia D. Jacinto, Director and Mr. Carlo M. Limbo, Research Associate Institute of Biology, University of the Philippines, Diliman
Adviser: Catherine Joy A. Addauan

Euphorbia milii cv., “The Crown of Thorns”, is a common species of Euphorbia that is widely distributed among different countries in Asia. Studies have indicated its toxicity against humans, and more studies have indicated its anti-oxidant, anti-mutagenic, anti-tumor and anti-cancer and many more of its biological activities. The researchers have come to recognize cancer as a prevailing cause of mortality worldwide, thus, this study aimed to determine the possible cytotoxic effect of Euphorbia milii cv. leaves on lung and colorectal cancer cell lines in order to provide a basis for upcoming similar researches.

The leaves were subjected to solvent extraction using methanol and afterwards, the extract was diluted in DMSO in preparation for the MTT Assay. Through the MTT Assay, the cytotoxic activity of the extract on lung and colorectal carcinoma was determined.

The results from the MTT Assay showed that the Euphorbia milii cv. leaf extract inhibited the cell growth of HCT116 and A549 cancer cells with its IC50 values 26.281 μg/mL and 33.96647 μg/mL respectively, making it effective in killing half (50%) the population of the cancer cells. Also, it has been found out that 100μg/mL concentration of Euphorbia milii cv. is the most effective of all the concentrations. Euphorbia milii cv., having found to exhibit a cytotoxic activity against human lung and colorectal carcinoma, is recommended for extensive studies implying further purification of its extract and a live cell count before and after treatment for more accurate results and a wider understanding of it.


(First Place, PSHS-CVC Local Science Fair – Technology and Engineering Category; Exhibited in the National Science and Technology Week in July 2015 at the SMX Convention Center, Pasay City)
Researchers: Bautista, Kim Wesley M.
Daquioag, Nelvinson N.
Narvadez, Patricia Nicole S.
Engr. Teofilo T. Sagabaen, Saint Mary’s University, Bayombong, Nueva Vizcaya
Adviser: Mr. Ronald M. Navalta

People today use electronic machines to aid them in day to day activities. Electricity is in high demand but the major resource from which we get energy is fast depleting. This research aimed to build a self-sustaining street light and charging station that utilizes solar energy.

The device can be simplified into three parts, namely: the automatically adjusting solar panel, the LED lamp, and the charging station. The device makes use of ZDS II - Z8 Encore! Family as its program. The solar panel adjusts towards the direction of the sun every hour but it can also be manually adjusted by the user. It uses a real-time clock (RTC) and pre–calculated angles of the sun. This function helped maximize the energy gathered by the solar panel throughout the day. The LED lamp was programmed to turn on and off by 7:00 AM and 7:00 PM, respectively. The charging station can charge devices with at most 2000 mAh batteries. The energy gathered by the panel is stored in a 12V battery that the device will make use of for the charging station and the LED lamp.

The device is self-sustaining, needing only an average of 5 hours to charge the required amount of AHr to supply the street light and the charging station in 24 hours.


(Finalist: PSHS System-wide Science Research Summit 2014; Semi-finalist, 9th Zonal High School Thesis Competition, Central Luzon State University)
Researchers: Clemente Ledger R.
Gumayagay, Kino Gabriel G.
Huggay, Rhonald Job D.
Mrs. Claribel A. Matias, Saint Mary’s University, Bayombong, Nueva Vizcaya
Adviser: Genalyn Alice R. Viloria

Free radicals are atoms or molecules that have unpaired electrons which can cause numerous diseases. Antioxidants, on the other hand, are substances that inhibit the oxidation of free radicals. Lately, there is an increasing interest in antioxidants, particularly towards the antioxidant activity of Dragon fruit. Dragon fruit, which is also known as pitaya is the fruit of a night blooming cactus. The study aims to evaluate the total phenolic content and the radical scavenging activity of the white fleshed dragon fruit peel, red fleshed dragon fruit peel, and the combination of the white fleshed dragon fruit and the red fleshed dragon fruit. The dragon fruit peels were consecutively extracted with ethanol to produce dragon fruit crude extracts. The extracts were separately added with their respective reagents with 3 replicates of the three extracts each in the determination of Total Phenolics Content and DPPH free radical scavenging activity.

The results of the study indicate that White-fleshed dragon fruit yielded the highest total phenolics content and radical scavenging activity compared to Red-fleshed dragon fruit, combination of White-fleshed dragon fruit and Red-fleshed dragon fruit, and the controls (Ascorbic Acid for Total Phenolics Content and Catechin for Free radical scavenging activity).

Based on the data gathered, there is a significant difference in the antioxidant properties of the dragon fruit peel extract treatments in terms of total phenolics content but not in terms of free radical scavenging activity. It was found that the white-fleshed dragon fruit (Hylocereus undatus) peel ethanolic extract significantly yielded the highest total phenolics content and qualitatively the highest free radical scavenging activity among the treatments followed by the 1:1 combination of the white-fleshed and red-fleshed dragon fruit peel extracts. These results imply that Hylocereus undatus peels are the best source of phenolics which can act as antioxidants but the antioxidant activities of all the dragon fruit peel extracts tested are comparable to each other and to the positive control, Catechin.

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



  (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
Naomi Renee Dominique B. Salagubang
Research Adviser:
Julius A. Garcia
Research Teacher: Genalyn Alice R. Viloria

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.



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
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

 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.




  (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

     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.



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

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.