Department of Chemistry

Malihao river was reported to have a decline in water quality over the years due to the increasing human activities surrounding the river. Various pollutants were present in the river such as suspended and dissolved solids, copper, lead, cadmium, and oil/grease; and their concentration levels are beyond the set limit by the national guidelines. The removal of these compounds was studied using waste bivalve shells is a suggested remedy, as they are locally available and abundant in the region. Total suspended solids were removed using chitosan from Perna viridis up to 81%; copper and lead were removed using Polymesoda erosa in a packed column; and oil/grease was efficiently removed using Crassostrea spp. up to 80-100%. Additional monitoring efforts in the locality should be done to properly manage this body of water to prevent from further deterioration.

Gel filtration of prolamine from cassava (Lakan-I
variety) containing 0.07 μg protein mg-1 sample revealed
two peaks. CSV PF01 (the pooled fraction of the peaks
of all runs) contains 0.42 μg protein mg-1 sample, while
CSV PF02 (fractions below the peak) contain 0.37 μg
protein mg-1 sample. Molecular weight estimation
revealed CSV PF01 to have a broad band at 60-65 kDa
while CSV PF02 has a band at 60-65 kDa and another at
around 67-70 kDa.
CSV PF01 is rich in glutamic acid (12.9%), tyrosine
(11.5%) and glycine (8.8%). Most predominant amino
acids in CSV PF02 are glutamic acid (16.8%), serine
(13.7%) and glycine (12.3%).
Evaluation of the nutritional parameters of the
cassava tuber prolamine CSV PF01 and CSV PF02
showed E/T% to be 49.2% and 37.6%, respectively. The
amino acid score patterns of Leu, Phe + Tyr, Thr and
Val for CSV PF01 are comparable with the FAO/WHO
reference protein while only Phe + Tyr and Thr are found
to be comparable with the FAO/WHO requirement. The
estimated protein efficiency ratio (PER) values for CSV
PF01 and CSV PF01 are 1.50–2.27 and 0.98–1.27,
respectively. The estimated PER values reveal that CSV
PF01 is a better protein than CSV PF02. In vitro protein
digestibility of the crude prolamine extract was
determined to be lower (67.6%) than casein (73.6%)
which was used as standard in the digestibility study.

Sources of cassava samples included 14 selected
cassava farms and six common market places in Iloilo.
Two major varieties of cassava were collected: those
with white roots and red petiole which belongs to the
Native/Balinghoy variety and those with yellow roots
and yellow green petiole belonging to the Golden
Yellow/Lakan I variety.
The cyanide content of the roots and leaves were
determined using the sodium picrate method. Color
chart readings for cyanide were compared with
spectrophotometric (spectro) readings to verify the
validity of the color chart results. Color chart readings
fall within range of the spectrophotometric results.
Statistical results show that the differences in the
concentrations of cyanide in cassava roots and leaves
from different sources were significant at 0.05 level.
Cyanide concentrations are higher in the leaves
(50.49+1.4 to 388.08+11.2) than in the roots (12.87+4.2
to 135.63+7.0) and also higher in the Native/Balinghoy
than the Golden Yellow/Lakan I variety. In leaves,
spectrophotometric values range from 91.08+2.8 ppm
(Naclub) to 216.81+26.6 ppm (Lambunao) for the
Golden Yellow/Lakan I variety; and from 50.49+1.4 ppm
(Sigangao) to 388.08+11.2 ppm (Naclub) for the Native
or Balinghoy variety. For the roots, results range from
12.87+4.2 ppm (Carmelo) to 75.24+2.8 ppm (Bungca)
for the Golden Yellow/Lakan I variety; and 17.82+0ppm
(Sigangao) to 135.63+7.0 ppm (Naclub) for the Native/
Balinghoy variety.
Length of storage period of cassava roots has
effect on cyanide content. When storage period is
extended cyanide content decreases significantly at
0.05 level.

The documentation of plants used as medicine is an important baseline for possible extraction, isolation, characterization, and chemical modification of important chemical compounds. This study aims to determine the plants used as medicine by traditional healers in Pagadian City, Zamboanga del Sur, Philippines. A total of 80 plants were mentioned by 11 traditional healers, who willingly shared their knowledge on medicinal plants. These plants were all recorded but only 71 plants belonging to 40 families were collected and identified. The remaining nine were only mentioned but no actual photos were taken and collected because these plants were inaccessible during the collection period and/or may have withered already. The botanical families with the highest number of species were represented by the families Lamiaceae and Moraceae (6), followed by Euphorbiaceae and Fabaceae (5). The most commonly used plant parts for herbal medicines are the leaves, and the most employed method of preparation is decoction. Among the illnesses mentioned for herbal medication were cancer (as the most cited), followed by kidney problems. This study also documented plants that are prepared in mixtures to treat illnesses like severe cough, severe diarrhea, and varicose veins. The information recorded and presented in this study may be useful for future phytochemical and pharmacological studies.

Mangroves are able to sequester atmospheric carbon not only in their above and belowground biomass but also in sediments for a long period of time. The study presented mainly focuses on the determination of Total Organic Carbon (TOC) and Carbon/Nitrogen (C/N) Ratio in surface sediments of two dominant mangrove species (Avicennia marina and Rhizophora mucronata) inhabiting the mangrove estuary of Getulio, Buenavista, Guimaras. The TOC content was determined by Walkley Black titration method, total nitrogen (TN) using macro-Kjeldahl analysis, C/N ratio calculated as TOC/TN and leaf litter fractionation using isolation techniques to separate carbon compounds into three components. Physico-chemical factors vary considerably between two mangrove site locations. Both Avicennia (MA) and Rhizophora (MR) site revealed an alkaline and saline environment suited for mangrove growth and productivity. The total organic carbon content was varying with depth and between the sites, where the highest total average value (4.84±0.62%) was found in the top layer of MA surface sediments and the lowest value (0.72±0.03%) was found at MR surface sediments mangroves planted 2 years after the oil spill incident in Guimaras on August 11, 2006. The TOC of surface sediments at the top 10 cm contained the largest percentage of organic carbon of all depth intervals from each mangrove site. Meanwhile, the C/N ratio of surface sediments decreased from MA to MN and increased from the upper layer to the lower layer. Recalcitrant carbon mainly consisted of lignocellulose compounds has an inverse relationship with TOC with respect to MA and MR as indicated by increasing TOC in sediment and decreasing lignin and hemicellulose content. This was accounted to the nature of the mangrove vegetation since MA is mature while MR is young planted. The hydrocarbon biomass

The principles of the Doehlert uniform shell designs (aka Doehlert designs) and their importance in the context of chromatography are discussed. The confidence of different models generated by Doehlert designs is studied by means of the uncertainty of the experimental points. The article provides an overview of analytical applications in chromatography with focus on single and coupled techniques and also discusses some reported blunders regarding Doehlert designs.

Pineapple (Ananas comosus) fruit is a functional food that has become a part of healthy diets worldwide due to its nutrition and health benefits. Given this concept, the potential anti-hypercholesterolemic activity of pineapple fruit was assessed using in vitro HMG-CoA reductase (HMGCR) inhibition assay. Our findings show that pineapple fruit (PAF) extract showed HMGCR inhibition activity. These findings led to partial purification of PAF extract by gel filtration chromatography (GFC) whereby fraction PAF 06 exhibited 100.00% HMGCR inhibition at 10 mg/mL. Matrix assisted laser desorption ionization (MALDI) mass spectrometry profiling, HRMS, MS/MS, and dereplication identified N1, N10-diferuloylspermidine as potential HMGCR inhibitor in pineapple fruit. The MALDI mass spectrometry imaging (MSI) enabled the in situ spatiotemporal mapping of the HMGCR inhibitor, N1, N10-diferuloylspermidine, in the pineapple fruit tissue, with localization concentrated mainly in the tissue near the peel/shell and a gradual decrease towards the flesh and ovary. The MALDI MSI provided the first evidence of in situ spatial localization of N1, N10-diferuloylspermidine, a potential HMGCR inhibitor in pineapple while maintaining the cellular and structural features of the fruit tissues.

Pineapple (Ananas comosus) fruit is a functional food that has become a part of healthy diets worldwide due to its nutrition and health benefits. Given this concept, the potential anti-hypercholesterolemic activity of pineapple fruit was assessed using in vitro HMG-CoA reductase (HMGCR) inhibition assay. Our findings show that pineapple fruit (PAF) extract showed HMGCR inhibition activity. These findings led to partial purification of PAF extract by gel filtration chromatography (GFC) whereby fraction PAF 06 exhibited 100.00% HMGCR inhibition at 10 mg/mL. Matrix assisted laser desorption ionization (MALDI) mass spectrometry profiling, HRMS, MS/MS, and dereplication identified N1, N10-diferuloylspermidine as potential HMGCR inhibitor in pineapple fruit. The MALDI mass spectrometry imaging (MSI) enabled the in situ spatiotemporal mapping of the HMGCR inhibitor, N1, N10-diferuloylspermidine, in the pineapple fruit tissue, with localization concentrated mainly in the tissue near the pee...