Optimisation studies were carried out on the basis of varying initial concentration of Chitosan and Xanthan, and varying pH of Chitosan solution. The results obtained were interesting. Unstable capsules were formed with the following combination of Xanthan and Chitosan concentration. The Chitosan solution pH was kept constant at 5.
The above table gives the inference that when Xanthan concentration is less than or equal to 0.5% or Chitosan concentration is less than or equal to 0.5%, the capsules formed are unstable.
Similarly, amorphous capsules were reported when the concentration of Xanthan was varied as shown in the given table. The Chitosan solution pH was kept constant.
This phenomenon was due to the increase in viscosity of Xanthan …show more content…
Hence, this concentration of Xanthan and Chitosan was taken as the optimum value. The bead diameter decreases with increase in concentration and viscosity of encapsulation solution.25 Another important observation made here is that at concentration of Xanthan and Chitosan at 0.75%, a mixture of stable as well as unstable capsules were formed. This can be attributed to the fact that the concentration of both Xanthan and Chitosan is close to the limits of workability range. Similarly when Xanthan concentration was approaching to that of 2%, the capsules were a mixture of both amorphous and stable ones. All the size was average of 10 capsules each from 3 …show more content…
The soaked freeze dried capsules in water for 12 hours resulted in a significant average swelling degree percentage of 160.8%. The significance of this swelling percentage is in the fact that unless the capsule swells to a certain degree, the microbes which are to be encapsulated would not be able to get released from the capsules. Hence it is necessary that the prepared capsules have sufficient swelling degree. Whereas, the experiment conducted by soaking the capsules in only Dodecane solution resulted in very negligible swelling.
The swelling is due to the fact that the carboxyl groups in the Xanthan neutralises in acidic solution while the amino group hold the positive charge which will cause the electrostatic linkages to disappear.27 An osmotic pressure is developed and the water enters the capsules. The capsule swells until equilibrium is reached between the osmotic pressure and the network forces of the linkages in PEC.
The absorbance value was measured by setting the wavelength at 600 nm and was found to be proportional to the cell concentration by a factor of
The above table gives the inference that when Xanthan concentration is less than or equal to 0.5% or Chitosan concentration is less than or equal to 0.5%, the capsules formed are unstable.
Similarly, amorphous capsules were reported when the concentration of Xanthan was varied as shown in the given table. The Chitosan solution pH was kept constant.
This phenomenon was due to the increase in viscosity of Xanthan …show more content…
Hence, this concentration of Xanthan and Chitosan was taken as the optimum value. The bead diameter decreases with increase in concentration and viscosity of encapsulation solution.25 Another important observation made here is that at concentration of Xanthan and Chitosan at 0.75%, a mixture of stable as well as unstable capsules were formed. This can be attributed to the fact that the concentration of both Xanthan and Chitosan is close to the limits of workability range. Similarly when Xanthan concentration was approaching to that of 2%, the capsules were a mixture of both amorphous and stable ones. All the size was average of 10 capsules each from 3 …show more content…
The soaked freeze dried capsules in water for 12 hours resulted in a significant average swelling degree percentage of 160.8%. The significance of this swelling percentage is in the fact that unless the capsule swells to a certain degree, the microbes which are to be encapsulated would not be able to get released from the capsules. Hence it is necessary that the prepared capsules have sufficient swelling degree. Whereas, the experiment conducted by soaking the capsules in only Dodecane solution resulted in very negligible swelling.
The swelling is due to the fact that the carboxyl groups in the Xanthan neutralises in acidic solution while the amino group hold the positive charge which will cause the electrostatic linkages to disappear.27 An osmotic pressure is developed and the water enters the capsules. The capsule swells until equilibrium is reached between the osmotic pressure and the network forces of the linkages in PEC.
The absorbance value was measured by setting the wavelength at 600 nm and was found to be proportional to the cell concentration by a factor of