Sources Through Catalytic Titration with Hexavalent Chromium

Overview

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Key numbers

The worker extracted the full PDF text with layout preservation twice and compared extraction hashes before commit. The following lines are copied from numeric/table-bearing regions of the PDF and retain the source units and wording where legible:

• oxalate, but it was reduced by 50 % after boiling for ten minute. The level of oxalate content in the analyzed fruit
• accumulating in the renal glomeruli, leading to renal disorder. Evidences showed that about 75% of all kidney
• All the chemicals used were of analytical grade reagent and used without further purification.98% H2SO4
• (analytical reagent, England), 37 % HCl (Aldrich, Germany), LC–MS-grade octanol (Sigma, Milwaukee,
• grinding and homogenizing the fruit and vegetables samples. An Agilent technology (1200 infinity series) HPLC
• discarded. All of the vegetables except beetroot were vacuum dried for 24 hour at 50 °C and then vacuum
• concentration of 0.1mM and it became the limiting reagent. That means in the reaction of Cr (VI) and Oxalic
• means the reduction works in acidic media. Cr (VI) has slow reduction at slightly acidic conditions (pH 5). In
• of its presence in most fruits and vegetables (21, 22). The effect of MA on the absorbance of the Cr (VI) and OA
• Table 1.The change in absorbance of chromium in absence and presence maleic acid
• result is summarized in Table 2. The values of LOD and LOQ (n=5) were determined as the analyte
• calibration curve (LOD) and 10 times standard deviation divided by the slope of the calibration curve (LOQ).
• Table 2. Oxalic Acid concentration in selected dietary source samples (Mean ± S.D, n = 3)
• (23). The high concentrations of OA in raw vegetables were also recorded as compared to values obtained from
• to elute at this retention time. Experimental conditions are shown in Table 3.
• Table 3. HPLC Chromatographic conditions (parameters) for analyzing OA standards
• Table 4.Total oxalic acid content of mango and Ethiopian collared green.
• amounts of total oxalate that were less than 25 mg/g (Table 2 and Table 4). These results suggest that, the
• The data in Table 4 is also reinforced by the corresponding decrease in the area under peak or intensities of the
• Percentage of oxalate loss due to cooking was calculated as 100-%TR (True Retention) (27).
• Therefore, the soluble oxalates in cabbage (GG) were reduced by 30.99% after boiling 5 min. However, the
• Ravindran (1992) (28) reported 40–50% loss of total oxalates when two kinds of yam tubers (Dioscoreaalata and
• D. esculenta) were boiled compared to steamed (20–25%). Judprason et al. (2006) (29) showed percentage loss
• oleraceavar.acephala) contained highest concentration of oxalate, but it was reduced by 50 % after boiling for
• 11. Chai, W. and Liebman, M. (2005a). Effect of different cooking methods on vegetable oxalate content.Journal
• 25. Abdel-Moemin, A. R. (2014). Oxalate Content of Egyptian grown fruits and vegetables and daily common

Methods (brief)

• optimized. The results showed that the amount of oxalic acid (mg/g) in vegetable samples of Ethiopian collared
• samples was found to decrease with increasing growing stage or state of ripeness. All studied food samples
• the current method and standard method (HPLC) were compared. In conclusion, the current method can
• successfully be used for determination of OA in fruit and vegetable samples.
• Keywords: Spectrophotometric titration, Hexavalent Chromium, Oxalic acid, HPLC.
• 10). Determination of oxalate in clinical samples such as urine and blood has thus served as a basis in diagnosis
• liquid chromatography (HPLC) (15-18).
• sample preparation, dilution and rinsing apparatus before sample solution preparation.
• (Pyrex, England), Volumetric flasks with stopper (Pyrex, England), Pyrex beaker to boil the real sample,
• grinding and homogenizing the fruit and vegetables samples. An Agilent technology (1200 infinity series) HPLC
• Samples were collected systematically from common market and fruit juice shops of Hawassa town. The fully
• the green leafy vegetable of lettuce, beetroot and cabbage and Ethiopian collared green were collected from
• of these samples were boiled for ten minute at room temperature and then cooled in cold water; the water was
• samples were ground into powdery form using mortar and pestle. The powdered samples were sieved to obtain
• Sample extraction for OA determination using UV-Vis Spectrophotometer method
• 1 g dried sample was weighed and boil in 150 ml water containing 27.5 ml 6 M HCl plus 2 drops of octanol for
• standard solution. 1 ml from each extracted sample and 9 ml from the blank solution, a total of 10 ml was taken
• for each sample and incubated for 60 min. Finally the total OA in the sample was analyzed using a UV–Vis

Implications

This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.

Wiki pages this source may touch

• Fish — marine, non-predatory (sardines, anchovies, salmon, cod)
• Root-Vegetable Purees
• Aluminum
• Chromium

Verification notes

• Identity check: DOI, raw handle, candidate cite-key, and SHA-256 were compared against existing wiki/sources/ pages before creation.
• Full-PDF read: pdftotext -layout was run on the full PDF twice; extracted text hashes matched before the page was written.
• Numeric verification: numeric/table-bearing lines were selected mechanically from the verified extraction and preserved without unit conversion or rounding.
• Brand firewall: the worker skips PDFs when extracted numeric lines appear brand/manufacturer-sensitive; this page contains category-level or species-level evidence only.
• HMTc firewall: no threshold, percentile, pass/fail, clean/dirty, or certification math is stated.

Update history

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