RESUMEN
Utilization of vegetable tannins in leather processing is one of the convenient solutions to protect the environment pollution. Herein, the banana bunch and syrup of banana stem are utilized to prepare an ecofriendly tanning agent. The yield of banana bunch extraction efficiency is found 69.80 %. FT-IR analysis confirmed the presence of condensed type tanning component owing to the bearing of different polyphenolic groups. The content of tannins in extracted banana bunch and stem syrup is 3.13 % and 2.6 %, respectively. The phenolic content in the banana bunch extract is determined to be 1332.37 mg GAE/100g of dried weight and in syrup was 873.92 mg GAE/100g of dried weight. This makes it possible to be used as vegetable tanners. The extracted bunch and syrup are applied to re-tan leather and compared with conventionally used vegetable tanning agent (quebracho) in parallel. Tensile strength, tear strength and elongation percentage for the extracted banana bunch and syrup are obtained at 23.84 N/mm2, 68.26 N/mm, 47.07 %, and 22.97 N/mm2, 68.38 N/mm, 40.70 %, respectively. The softness is found 1.41 for the extracted bunch and 2.01 for the syrup. The grain crack load, distension at grain crack, strength at ball burst, distension at ball burst are 246.86 N, 13.24 mm, 530.77 N, 24.54 mm for banana stem syrup and 338.77 N, 13.42 mm, 460.65 N, 29.08 mm for bunch extract, respectively. The shrinkage temperatures recorded for banana bunch extract, syrup and Quebracho (control trial) tannins tanned leather samples are 76.5 °C, 75 °C and 84 °C subsequently. The flexing endurance of the bunch extract and syrup revealed acceptable values that are less than 4. Moreover, the bunch extract tanned leather shows greater thermal stability and for syrup it is similar with the quebracho tanned leather. All the results are satisfactory compared to the control trial. Finally, tanned leather is evaluated to assess the possibility of the newly developed tannin which proves its efficiency as a potential source of tanning material for the leather industry.
RESUMEN
The traditional causes of Chronic Kidney Damage (CKD) are Diabetes and Hypertension. However, recent studies reported the possible relations between metal exposure and CKD. This study aims to explore the status of metals in CKD patients compared to their healthy counterparts at Narayanganj, Bangladesh, through a cross-sectional study. In this study, 50 volunteers were involved; 30 CKD patients and 20 healthy controls. Five metals were measured from serum [Copper (Cu) and Zinc (Zn)] and urine [Lead (Pb), Cadmium (Cd), and Chromium (Cr)] using Atomic Absorption Spectrometry. Compared to the controls the CKD patients exhibited significantly higher levels of Pb, Cd and Cr levels in their urine samples. This signifies a potential association between heavy metal exposure and CKD. The serum levels of Cu were much higher than expected for CKD patients than controls, and the Zn values were in accordance with established literature. However, the level of Zn in blood was significantly lower in the CKD group compared to the control. This data suggests that the Cu imbalance in the serum of the CKD subjects might have been related to a myriad of reasons, the most plausible of which being exposed to large concentrations of the nephrotoxic metals such as Pb, Cd and Cr in this study. Our study has shed a much needed light on the correlation between CKD and exposure to heavy metals and imbalance of essential metals in blood serum, in a rural locality of Bangladesh.