Combinatorial approach of statistical optimization and mutagenesis for improved production of acidic phytase by Aspergillus niger NCIM 563 under submerged fermentation condition.

Combination of statistical optimization and mutagenesis to isolate hypersecretory strains is studied to maximize phytase production from Aspergillus niger NCIM 563 under submerged fermentation. The overall results obtained show a remarkable 5.98-fold improvement in phytase production rates when compared to that using basal medium. Optimization of culture conditions from parent strain is studied first by the Plackett-Burman technique to evaluate the effects of 11 variables for phytase production. The results showed that glucose, MgSO(4), KCl, incubation period, and MnSO(4) are the most significant variables affecting enzyme production. Further optimization in these variables, using a central composite design technique, resulted in 3.74-fold increase in the yield of phytase production to 254,500 U/l when compared with the activity observed with basal media (68,000 U/l) in shake flask. Our experiments show that the phytase from A. niger NCIM 563 exhibits desirable activity in simulated gastric fluid conditions with low pH and also improved thermostability when compared to commercial phytase. The improved yield demonstrates the potential applicability of phytase enzyme as a source of phytase supplement for phosphorus nutrition and environmental protection in animal feed industry. Physical and chemical mutagenesis experiments were carried out in parallel to isolate hypersecretory mutants that could possibly further enhance the enzyme production. Using optimized media conditions of the parent strain, our results show that mutant strain A. niger NCIM 1359 increased the phytase activity by another 1.6-fold to 407,200 U/l.

Familial torticollis with polydactyly: manifestation in three generations.

Familial transmission of congenital muscular torticollis (CMT) has been reported in the literature, and postaxial polydactyly has been frequently reported in familial cases, but, to our knowledge, familial CMT with postaxial polydactyly has not been described. In this article, we report a rare case of CMT with postaxial polydactyly in 3 generations of a family and suggest an autosomal-dominant pattern of inheritance in these cases.

The Antley-Bixler syndrome: two new cases.

The Antley-Bixler syndrome is a rare multiple congenital anomaly with a high mortality rate. The characteristic manifestations include craniosynostosis, radiohumeral synostosis, midface hypoplasia, joint contractures and arachnodactyly. We report two new cases of this syndrome and address the diagnostic features, associated malformations, inheritance patterns, prenatal findings, and briefly review the literature.

Crossed polydactyly.

A common and conspicuous congenital hand anomaly, polydactyly commonly involves only the hand or the foot. Polydactyly involving both hands and feet is rare. We herewith report two cases of Crossed Polydactyly (Type I) and review the literature.

Mohr syndrome: a rare case and distinction from orofacial digital syndrome 1.

In view of the different modes of inheritance and the different prognoses of the two oro-facio-digital syndromes, type 1 and type 2, it is important to establish a correct diagnosis in these patients. A case of type II oro-facio-digital syndrome is being reported and the distinguishing clinicoradiological features with type I are compared.