UPV Digital RepositoryUPV-DRUniversity of the Philippines Visayas
 

Undergraduate Theses

Permanent URI for this collectionhttps://hdl.handle.net/20.500.14583/13

Browse

Filters

2015 - 20164

Settings

AGROVOC Keyword: search.filters.agrovoc.phytochemicalsCommittee Chair: search.filters.chair.Janagap, Steve P.

Search Results

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    Phytochemical screening, antibacterial and antioxidant activity of Ethanolic seed extract of Kadios (Cajanus cajan) from Igbaras, Iloilo, Philippines
    Bautista, 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.
  • Thumbnail Image
    Item
    Phytochemical screening, antioxidant activity, and comparative bioefficacy assessment of Camansi (Artocarpus camansi) seed extracts for in vitro antibacterial activity
    Bantayan, 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.
  • Thumbnail Image
    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%).
  • Thumbnail Image
    Item
    Antibacterial activity, antioxidant property and photochemical analysis of crude ethanolic extract from Dalanghita (Citrus nobilis) peels
    Aglobo, 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.