Occurrence and Sources of Pent acyclic Triterpenol Methyl Ethers and Alkanones as Molecular Indicators in Suspended Particulate Matter from Great Kwa River, Southeast Nigeria (Published)
Occurrence and source identification of Pentacyclic Triterpenol methyl ethers and alkanones as molecular indicators in suspended particulate matter obtained during high and low tides from Great kwa River, South East, Nigeria were characterized using gas chromatography- mass spectrometry (GC-MS) technique. Pentacyclic Triterpenol methyl ethers (PTMEs), taraxer-12-en-3-one, taraxer-14-en-3-one, taraxerone, taraxerol, miliacin, β-amyrin methyl ether, α-amyrin methyl ether, β-amyrenyl acetate, α-amyrenyl acetate and friedelin were characterized in the suspended particulate matter. Alkanones such as 6,10, 14-trimethyl pentadecan-2-one, pentacosan-2-one, heptacosan-2-one, octacosan-2-one, nonacosan-2-one, triacontan-2-one, hentriacosan-2-one, dotriacotan-2-one and tritriacotan-2-one were also found. These distinct compounds are useful for assessing diagenetic transformation that occurs during transportation of organic detritus. PTMEs are biomarkers of specific higher plants species, while alkanones are indication of direct microbial oxidation of the n-alkanes derived from epicuticular vascular plant wax. The presence of taraxerol and its ketonic counterpart taraxerone in the sample was an indication of dominant inputs from the study area vegetation and also reflect the oxidation and direct biological inputs. The accumulation of these compounds during low tide than high tide was due to sedimentation and oxidative process of the organic matter.
Keywords: Occurrence, PTMEs, SPM, Sources, alkanones, molecular indicators
INFLUENCE OF CALCIUM SOURCES AND CONCENTRATION ON THE STORAGE PERFORMANCE OF STRAWBERRY FRUIT (Review Completed - Accepted)
The Influence of calcium sources and concentration on the storage performance of strawberry fruit was determined by harvesting the fruits at red stage and treatment with calcium nitrate, calcium gluconate and calcium chloride at 0% (distilled water), 0.5, 1.0 and 1.5% calcium solutions by dipping for 30 seconds. The calcium sources, concentration and the interaction of calcium sources and concentration significantly affected the storage performance of strawberry fruit. While all the three sources and concentrations were effective in decreasing the storage associated changes i.e. weight loss, decline in marketable fruits, loss of organoleptic quality, increase in TSS, decline in reducing sugars, total sugars and acidity and increase in Sugar/ Acid ratio in strawberry fruit, thus extended the shelf life, Calcium gluconate and calcium concentration of 1.5% was more effective. Treatment of strawberry fruit with 1.5% calcium from Calcium gluconate source resulted in the highest number of marketable fruit (100%), extended shelf life (10 days) total soluble solid (7.80%) with the minimum weight loss (5.45%). Ascorbic acid content was the highest (35.35 mg/100 g) in fruits treated with the calcium nitrate at 1.0% calcium concentration but was at par with Calcium gluconate. It can be concluded that calcium gluconate at 1.5% concentration is an effective calcium treatment to retain the quality and extend the shelf life of strawberry fruit.
Keywords: Calcium, Concentrations, Fruit, Perishable, Quality, Salts, Sources, Storage, Strawberry
