Evaluation of the antioxidant activity of Annona muricata (Guyabano) mediated silver nanoparticles and Annona muricata ethanolic leaf extract

ANN THERESE S. SOBRETODO, MICA ANTONIA D. JAEN, RICHLYN JOY S. VILLALOBOS, and RAMON ANGELO N.
SINCO
Philippine Science High School – Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology – Science Education Institute, Philippines


Abstract
Silver nanoparticles (AgNPs) biosynthesized from various plant sources is an emerging material used for several applications. These may be used as antioxidants as several studies have focused on its ability to eliminate free radicals. Annona muricata (Guyabano) leaves are commonly known to possess such antioxidant properties due to its present bioactive compounds—thus becoming a suitable capping agent for AgNPs. The present study compared the antioxidant activity of A. muricata leaf extract, A. muricata mediated AgNPs, and commercially available AgNPs against ascorbic acid (positive control) and methanol (negative control) via DPPH Assay. Results show the leaf extract having the highest antioxidant activity after the positive control. This suggests that the plant extract can primarily be used as an antioxidant while the synthesized AgNPs do not contribute to its antioxidant property.

Keywords: Annona muricata, silver nanoparticles, antioxidant, DPPH Assay, biosynthesis


The effects of acetylcarnitine on the prevention of platelet storage lesions

JOHANNES TRÉ Z. MAQUILING, JOHN MARK E. VILLANUEVA, and ZENNIFER L. OBERIO
Philippine Science High School – Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology – Science Education Institute, Philippines


Abstract
Platelet storage lesion is the degradation that platelets experience when stored in an external environment, causing a loss in platelet viability and leading to a shelf life in platelets. This study aims to prevent platelet storage lesion by using preservatives to slow down its effects. The main aim of the study is to compare the effects of l-carnitine, an alternative preservative that lengthens platelet shelf-life from seven (7) to ten (10) days, with its derivative acetylcarnitine in respect to pH, platelet count, platelet volume, and platelet shape change. Three blood bags were used and separated into three setups, with either addition of l-carnitine, acetyl carnitine or saline (control) and stored at 22°C. Platelet count and mean platelet volume were determined by the use of an ABX Micros ES 60 hema-analyzer, and pH was determined by using a pH meter. Platelet morphology was observed by collecting stained samples and observed under a microscope, where regular and irregular platelets were recorded. Due to an anomaly, platelet count was not included in the analysis. One-way analysis of variance for mean platelet volume, pH and morphology did not show significant difference (p>0.05) among the setups, showing that further studies should be done to determine if acetylcarnitine might be a possible preservative for platelets.


Keywords: Platelet storage lesion, L-carnitine, Acetylcarnitine, Preservatives, Platelet viability


Evaluation of alanine-silver nanocomposites from biosynthesized silver nanoparticles

ANGELA JOYCE T. LOOT, MCXEL S. NUNAG, RASHEEN C. RABINO, and ARIS C. LARRODER
Philippine Science High School – Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology – Science Education Institute, Philippines



Abstract
Exposure to ionizing radiation damages the genetic material of living cells which may eventually become cancerous. Alanine- silver nanocomposites have recently been developed as a liquid detector for radiation dosimetry purposes. Despite this application, none have so far investigated the use of iosynthesized silver nanoparticles in the synthesis of alanine-silver nanocomposites. This study aimed to spectrophotometrically evaluate the interaction of biosynthesized silver nanoparticles and alanine in the formation of alanine-silver nanocomposites. The formation of silver nanoparticles was confirmed by ultraviolet-visible (UV-Vis) spectroscopy and transmission electron microscopy (TEM). The absorbance level of the alanine-silver nanocomposite solution was determined using UV-Vis spectroscopy. It was observed that the silver nanoparticles formed were spherical with a mean size of 27 nm. The interaction of alanine with silver nanoparticles yielded no visible color change. However, a trend of increasing absorbance level was observed. In conclusion, biosynthesized silver nanoparticles can be possibly used in the synthesis of alanine-silver nanocomposites. Further investigation on the effect of alanine to the size and morphology of silver nanoparticles is recommended.

Keywords: nanocomposite, biosynthesis, uv-vis spectroscopy, alanine, radiation dosimetry


Antibacterial properties of Dioscorea alata (purple yam) peel extracts against selected gram-negative and gram-positive bacteria

MIKA MONIQUE Z. GRANTOZA, ALLYZZA T. MATIONG, IAN RODRIGO B. SEGUANO, and ZENNIFER L. OBERIO
Philippine Science High School – Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology – Science Education Institute, Philippines


Abstract
Rapid emergence of resistant bacteria is endangering the efficiency of antibiotics which previously saved millions of lives. The antibacterial agent in plants is a notable source of new antibiotics alternatives. In the Philippines, Dioscorea alata is a main export banner crop since the country is the only supplier of the tuber in the world market. D. alata tubers have bioactive compounds including alkaloids, tannins, flavonoids, and saponins. In this study, the antibacterial properties of Dioscorea alata peel extracts were evaluated against four selected human pathogens including gram-negative bacteria, Escherichia coli and Enterobacter aerogenes and gram-positive bacteria, Staphylococcus aureus and Bacillus subtilis. Extracts were obtained through maceration and rotary evaporation. Activities of different concentrations (25%, 50%, 75%, 100%) of the peel extracts were evaluated using agar-well diffusion method on Mueller-Hinton agar. Inhibitory properties were identified only against selected gram-positive bacteria strains, S. aureus (50%, 75%, 100%) and B. subtilis (75% and 100%). For more results, D. alata extracts are recommended to be tested against other bacteria strains by different solvents with varying polarity.

Keywords: antibacterial, agar well-diffusion method, Dioscorea alata, purple yam, peels


Larvicidal activity of individual and combined ethanolic extracts of Annona muricata (Soursop) seed and Piper betle (Betel) leaf against Aedes aegypti

RALPH MARU M. GRANDE, MAXINE DANIELLE A. BALMACEDA, MADELEINE THERESE T. TANEÑA, and HAROLD P.
MEDIODIA
Philippine Science High School – Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology – Science Education Institute, Philippines


Abstract
The present study investigated the larvicidal activity of individual and combined ethanolic extracts of Annona muricata seed and Piper betle leaf against third and early fourth instar Aedes aegypti larvae. Larvicidal bioassays were done according to the World Health Organization 2005 guidelines for laboratory testing of mosquito larvicides. Individual larvicidal bioassays for A. muricata and P. betle exhibited LC 50 values of 16.45 ppm and 847.86 ppm, respectively. Between the two combined extract test ratios, the 70:30 (A. muricata:P. betle) ratio was more effective with an LC 50 of 116.51 ppm compared to the 152.16 ppm LC 50 value of the 50:50 (A. muricata:P. betle) ratio. Results reveal A. muricata extract in this study exhibits greater larvicidal effect compared to previous larvicidal studies using similar extract. A. muricata seed and P. betle leaf ethanolic extracts are effective larvicides both used individually and in combination against third and early fourth instar A. aegypti larvae.


Keywords: Annona muricata, Piper betle, Aedes aegypti, larvicidal bioassay, ethanolic


An exploratory study on the anti-Angiogenic Property of Ficus benjamina Crude Methanolic Leaf Extract Using Duck (Anas platyrhynchos) Chorioallantoic Membrane (CAM) Assay

LYZ THERESE D. CAINGLET1, AUBREY BEATRICE B. CARNAJE1, ANDREI A. YANSON1, ATHENES JOY P. ABAN1, and RICHIE G. BAYURAN2
1Philippine Science High School – Western Visayas Campus, Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology – Science Education Institute, Philippines
2Saint Gabriel College, Kalibo, Aklan


Abstract
Anti-angiogenesis is the inhibition of the growth of blood vessels. Ficus benjamina is a tree classified under the Moraceae family, and can be frequently seen in households in the Philippines where it commonly grows and is native to Asian countries. The duck chorioallantoic membrane (CAM) assays were treated with positive control (Doxycycline), negative control (Distilled Water), and crude methanolic leaf extract of Ficus benjamina in 3 different concentrations (100 mg/disc, 10 mg/disc, 1 mg/disc). After 72 hours of treatment, the following parameters: total number of branches and total branches length (in pixels), were measured using the ImageJ software. Results show that the values for both parameters of blood vessel growth in CAM assays treated with Treatment 1 (100 mg/disc) were comparable to that of the positive control (Doxycycline). Therefore, the crude methanolic extract of Ficus benjamina exhibits strong anti-angiogenic activity.

Keywords: anti-angiogenesis, CAM Assay, Ficus benjamina, Moraceae, ImageJ


The antibiofilm activity of peel extracts of Mangifera indica L. (Carabao mango) at different ripeness stages against Staphylococcus aureus biofilm

BIANCA JULLIANA MARIE N. BAT-OG, KEANE MARCEL V. ORETA, TRINA THERESE M. VILLAFLOR, and FERNANDO
CHRISTIAN JOLITO III
Philippine Science High School- Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology – Science Education Institute, Philippines


Abstract
Staphylococcus aureus biofilm is a matrix composed of extracellular polymeric substances (EPS) that protect bacteria and is responsible for antibiotic resistance and many osocomial infections. It can be broken down by phytochemicals such as tannins, flavonoids, alkaloids, quinones, and saponins found in Mangifera indica L. These compounds are influenced by ripening of the fruit. The study focused on determining the ripeness stage that produced the peel extract with the most effective antibiofilm properties. Phytochemical screening and biofilm assay were conducted and absorbance values and percent reduction were obtained. At 50% concentration, none of the
samples showed antibiofilm activity. At 25% concentration, all except the extract from ripeness stage 2 fruits exhibited antibiofilm activity. At 10% concentration, all extracts exhibited antibiofilm activity. In conclusion, no trend for antibiofilm activity was observed for ripeness stages. Decreased concentration of extracts yielded greater antibiofilm activity which was contradictory to many cited studies.

Keywords: antibiofilm, Staphylococcus aureus, Mangifera indica L., ripeness stages, peel extracts


Biofilm dispersal effects of Fenton’s reagent on Staphylococcus aureus biofilm

JEAN DOROTHY B. ANDRADA, JOSE GABRIEL R. JAVELLANA, FELIZ ISABEL C. LICUP, and ANDREA LUCYLE M. BELA-ONG
Philippine Science High School – Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology – Science Education Institute, Philippines


Abstract
Staphylococcus aureus biofilms have shown significant resistance against antibiotics. A potential approach to counter this is through inducing biofilm dispersal. Fenton’s reagent, a solution which contains the reactive hydroxyl radical (OH•), may be a potential agent of biofilm dispersal. Although Fenton chemistry has proven to have antibacterial effects, the effect of Fenton’s reagent itself against a biofilm has not yet been determined. This study aims to evaluate the biofilm dispersal effects of Fenton’s reagent on an S. aureus biofilm, through the use of the crystal violet assay and microplate reading at OD620. It was found that Fenton’s reagent does not induce biofilm dispersal; rather, it induces biofilm formation at 100 μL and has no effect at 200 μL. This may have been due to excess Fe 2+ ions and due to the reactive hydroxyl radical already being consumed by the time of the reagent’s application. It was concluded that Fenton’s reagent may induce biofilm formation instead of biofilm dispersal, depending on the ratio between the volume of Fenton’s reagent and the biofilm mass.

Keywords: Fenton’s reagent, biofilms, anti-biofilm, biofilm dispersal, Staphylococcus aureus


Effect of UV Radiation (365nm) to Production of Antimitotic Compounds in Arachis hypogaea (Peanut) Roots

ZYRA B. ABELLAR, ELLEN RAE MARGARET G. DE JUAN, and ANDREA LUCYLE M. BELA-ONG
Philippine Science High School – Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology – Science Education Institute, Philippines


Abstract
Arachis hypogaea, commonly known as peanut, is a legume reported to contain phytoalexins that are potentially antimitotic. Phytoalexins are substances produced by plants as a response to numerous biotic and abiotic stresses, such as fungal and viral infections, ultraviolet (UV) radiation and ultrasonic exposure. The present study assessed the efficacy of UV radiation in inducing the production of phytoalexins through the Allium cepa root tip technique. Crude root ethanol extracts of A. hypogaea plants exposed and unexposed to UV radiation (3 mg/mL and 5 mg/mL), and tap water were compared. Results showed that the 5 mg/mL concentration of the UV-exposed plants was the only treatment which showed significant antimitotic potential compared to other treatments. However, optimum concentration ranges between 5 to 10 mg/mL only. In conclusion, exposure of the A. hypogaea plants to UV radiation aids the increase of production of antimitotic compounds present in A. hypogaea roots.

Keywords: Arachis hypogaea, Allium cepa root tip technique, ultraviolet (UV) radiation, phytoalexins, mitotic index (MI)


Determining the Bacterial Content of Fresh And Cooked Sea Cucumbers Sold for Food Consumption in Panobolon Island, Nueva Valencia, Guimaras

JOEMIL E. AGUADO JR., MICHAEL JOHN F. ARO, NOEL IVAN A. LOMIGO, and HAROLD P. MEDIODIA
Philippine Science High School – Western Visayas Campus, Brgy. Bito-on, Jaro, Iloilo City 5000, Department of Science and Technology – Science Education Institute, Philippines


Abstract
Bacterial contamination in commercially sold sea cucumbers is hugely understudied in Western Visayas. The study aimed to tackle the problem of bacterial contamination in commercially sold sea cucumbers in Panobolon Island, Guimaras by determining its bacterial content. The cooked and fresh sea cucumber samples used in this study were bought from the local market and were identified as the species Holothuria scabra, a common species of sea cucumber consumed as food in Western Visayas. Bacteria was isolated from both the fresh and cooked samples and cultured directly unto the selective media. Results showed that the bacterial content in cooked samples were more compared to the fresh samples. Both types of samples contained Staphylococcus aureus, while Escherichia coli and Pseudomonas aeruginosa were only present in cooked samples. Salmonella spp. was only present in fresh samples, while Shigella spp. was not found in any of the samples. The bacteria found in the fresh samples are known to be found in sea water and the content of the cooked samples can be attributed to the food handling of the residents.


Keywords: sea cucumbers, bacterial content, bacterial isolation, Public Health, food handling