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Item Phytochemical screening, antibacterial and antioxidant activity of Ethanolic seed extract of Kadios (Cajanus cajan) from Igbaras, Iloilo, PhilippinesBautista, 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.Item Hydrogel composites loaded with plant extract as an antibacterial and quorum sensing inhibiting wound dressingBaranda, 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.Item Phytochemical screening, antibacterial and antioxidant activities of the crude ethanolic extract of calamansi (Citrus microcarpa) peelsBaquiano, 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.Item Phytochemical screening, antioxidant activity, and comparative bioefficacy assessment of Camansi (Artocarpus camansi) seed extracts for in vitro antibacterial activityBantayan, 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.Item Antioxidative properties of the fruits of selected tomato (Lycopersicon esculentum Mill.) varietiesBaltazar, Gleza Wae D. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2016-05)This study was conducted to compare the antioxidative properties of greenstage fruits of selected Lycopersicon esculentum Miller varieties (Diamante, Diamante Max, and Pidada) from Barangay Durog, Miagao, Iloilo. The fresh fruit samples were extracted with 95% ethanol. The crude extracts were concentrated using rotary evaporator. The antioxidant activity of the ethanolic fruit extracts was assayed for DPPH radical scavenging activity and the IC50 values were determined. The determination of the phenolic and flavonoid contents was done employing Folin- Ciocalteu method and aluminum chloride spectrophotometric method, respectively. The results show that the fruits of the studied L. esculentum varieties exhibit DPPH radical scavenging activity. The IC50 values, however, differ significantly among the varieties. The IC50 values for Diamante (24.22 ± 1.41 g/L) and Diamante Max (25.08 ± 0.45 g/L) are comparable but are significantly lower than Pidada (29.47 ± 1.33 g/L). These findings imply that Diamante and Diamante Max varieties have stronger antioxidative capacity than the Pidada variety. Moreover, the results indicate that the antioxidative property of L. esculentum is variety-dependent. The results of the determination of the total phenolic content, expressed in mg gallic acid equivalent (GAE) per g fresh sample, are in the order of 0.16 ± 0.02 mg GAE/g for Diamante > 0.15 ± 0.02 mg GAE/g for Diamante Max and Pidada. On the other hand, the results of the determination of the flavonoid content, expressed in μg quercetin equivalent (QE) per g fresh sample, are in the order of 6.31 ± 1.27 μg QE/g for Diamante >6.21 ± 0.88 μg QE/g for Diamante Max > 5.63 ± 0.94 pg QE/g for Pidada. No significant difference in the total phenolic and flavonoid contents was found among varieties. Nonetheless, the detection of phenolics and flavonoids, known antioxidants, supports the present results on the antioxidative property of the fruits of the L. esculentum varieties studied.Item Antioxidant property, total phenolics, manganese and iron content of humic acid obtained from Sta. Barbara, Iloilo artesian well waterBaltazar, Lenmark Anthony M. (Division of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2016-06)The town of Santa Barbara in Iloilo is famous for its reddish browncolored well water due to the presence of humic acid which makes up most of the water’s natural organic matter content. Because the well water is used by the local townsfolk for drinking and other domestic activities, it is imperative that a study must be made to assess its potential health benefits and risks. In this study, the DPPH radical scavenging activity of the extracted humic acid was investigated. It was determined that the sample contains antioxidants capable of reducing DPPH with an IC5o of 51.552± 0.652 ppm. Prussian Blue Assay for total phenolic content also showed that a 76.5 ppm humic acid sample has 14.169 ± 1.151 ppm in GAE. Flame-AAS analysis showed that the humic acid sample contains iron (0.8376 ± 0.0581 ppm). The manganese content of the sample was below the detection limit of the instrument. The results suggest that the humic acid extracted from the well water contains potential antioxidants which can be exploited for various commercial and medical applications.Item Antioxidant property of anthocyanin from malatinta (Phyllanthus reticulatus Poir.) fruits obtained by static and microwave-assisted extractionBaldonasa, RB Hera Angelica R. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2015-06)Fresh fruits of Phyllanthus reticulatus Poir. were analyzed for anthocyanin by spectrophotometric method. The antioxidant activity using 1,1 -diphenyl-2-picrylhydrazyl (DPPH ) free radical scavenging activity (FRSA) and reducing power (RP) through FeCl3 assay were determined. The use of two extraction processes, namely, the static method and microwave-assisted extraction, using two extraction solvents, acidified methanol and aqueous ethanol (1:1) were compared. The total anthocyanin content (TAC) of P. reticulatus fruit was highest in extract using static method of extraction in acidified methanol solvent (279.94 ±17.31 mg/lOOg), comparable to levels found in plants rich in anthocyanins, (e.g., berries genotypes, grapes and red cabbages). In microwave-assisted extraction, TAC using acidified methanol was higher (278.01 ± 18.76 mg/lOOg) compared to using aqueous ethanol (210.96 ± 2.02 mg/100g). P. reticulatus fruits exhibited high antioxidant activity as revealed by its RP and DPPH FRSA results when compared to ascorbic acid. These findings highlight the usefulness of P. reticulatus as a source of anthocyanins with good antioxidant properties, which, in turn, gives importance to the undervalued and underutilized plant.Item Phytochemical, antioxidant, and antibacterial analysis of essential oils from Zingiber officinale Roscoe(Ginger) and Curcuma long Linn.(Turmeric)Alviar, Joseph Noel G. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2015-06)This study was conducted to characterize and compare the phytochemistry, antibacterial and antioxidant activities of essential oils extracted from the rhizomes of Zingiber officinale Roscoe (ginger) and Curcuma longa Linn. (turmeric). Percent yields in the steam distillation of ginger and turmeric were 0.42±0.02% and 0.43± 0.02%, respectively. Qualitative phytochemical screening showed that both essential oils are positive for flavonoids, phenols, saponins, terpenoids, tannins, and quinones. Antibacterial activity was tested against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli using 100%, 75%, 50%, and 25% (v/v) essential oil in ethanol with positive control tetracycline and negative control ethanol. It was determined that C. longa did not have antibacterial activity against both bacteria while Z. officinale had “moderately inhibitory” to “strongly inhibitory” activity against S. aureus with zone of inhibition (ZOI) from 17.67±1.53 mm to 23.67±0.58 mm and “weakly inhibitory” to “moderately inhibitory” activity against E. coli (ZOI from 12.33±1.15 mm to 15.67±2.08 mm). The standard antibiotic tetracycline also showed “moderately inhibitory” activity against both S. aureus (ZOl = 19.00±0.89 mm) and E. coli (ZOI = 17.33±1.21 mm). Antioxidant activity was determined by DPPH free radical inhibition. Highest % DPPH free radical inhibition was exhibited by the standard antioxidant ascorbic acid (92.98%), followed by C. longa essential oil (88.74%), and Z. officinale (76.30%).Item Antibacterial activity, antioxidant property and photochemical analysis of crude ethanolic extract from Dalanghita (Citrus nobilis) peelsAglobo, Jastine S. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2015-05)The crude ethanolic extract of Dalanghita (Citrus nobilis) was studied for their antibacterial activity, antioxidant and phytochemical properties. The DPPH free radical scavenging assay of extracts with varying concentrations showed strong antioxidant activity with a maximum % inhibition of 92.30 at 80.70 ug/mL concentration. The IC50 was calculated to be 26.26 pg/mL against 12.48 ug/mL for Ascorbic acid, the positive control. The antibacterial activity of the extract was determined against Escherichia coli and Staphylococcus aureus by measuring the mean zones of inhibition using the paper disc diffusion assay at different concentration of crude ethanolic extract. The crude ethanol extract at 100% concentration yielded the highest inhibition for E. coli at 21.50±0.50 mm which is comparable to tetracycline, the positive control. The presence of phytochemicals in the extract were evaluated and the phytochemicals identified were: alkaloids, flavonoids, saponins, steroids, tannins, and terpenes.Item Optimization of extraction Conditions of water-soluble phenolics from tawa-tawa (Euphorbia hirta L.) based on Densitometric TLC using gallic acid as marker compoundAborka, Ma. Ayanne B. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2015-06)The present study aimed to optimize the extraction conditions of water-soluble phenolics for tawa-tawa (Euphorbia hirta L.) with gallic acid as the compound of interest. Water was used as extraction solvent. The effect of the interactions of different extraction temperature (50°C, 60°C and 70°C) and extraction time (20 min, 40 min and 60 min) were investigated. To evaluate the importance of the parameters on the extraction efficiency of gallic acid, a factorial design was used. The normal probability plot and estimates of standard error showed that time and temperature were both significant parameters. It further showed that time was a more significant contributor than temperature to the extraction efficiency of gallic acid. The results revealed that interaction of time and temperature did not have significant effects. The ANOVA results showed that only extraction parameter with significant effect was time (p < 0.05). Temperature and its interaction with time did not have significant effects. Based on the desirability values generated by Design-Expert 9.0.4, the optimal conditions in extracting gallic acid were the following: extraction time of 60 minutes and extraction temperature of 70°C. Results of FTIR analysis confirmed the presence of the following functional groups: O-H, C=O, C-O, C-H (aromatic), C=C (benzene) and out-of-plane bending or oops. Gallic acid in tawa-tawa is present in esterified form and exists as part of hydrolysable tannins.