Antimalarial activity study of organotin(IV) derivatives with nitrobenzoic acid derivatives used as ligands has been performed. The targeted compounds were prepared from their organotin(IV) chlorides via dibutyltin(IV) oxide, diphenyltin(IV) dihydroxide, and triphenyltin(IV) hydroxide intermediate products, followed by reacting the intermediate products with 2-nitrobenzoic acid. The antimalarial activity was performed against P. falciparum. The results showed that the IC50values of dibutyiltin(IV) di-2-nitrobenzoate, diphenyltin(IV) di-2-nitrobenzoate, and triphenyltin(IV) 2-nitrobenzoate were in 8.4 × 10‑3, 5.3 × 10–2, and 9.1 × 10–3 µg/ml, respectively. The IC50 values were slightly higher than the value for chloroquine (2 × 10–3 µg/ml) used as the positive control; however, one advantage is that all prepared organotin(IV) compounds were not resistant to Plasmodium, making the use of organotin(IV) as an antimalarial is possible. The results indicated that the derivative of triphenyltin(IV) was more potent when used as an antimalarial, as expected, and has potential to be developed as an antimalarial drug in the future.

A series of di-and tributyltin(IV) carboxylate compounds prepared by reacting the dibutyltin(IV) dichloride and tributyltin(IV) chloride respectively via the organotin(IV) oxide with the respective carboxylic acids have been tested for antifungal activity against Fusarium oxysporum and Aspergillus niger in potatoes dextrose agar. The compounds synthesized were mainly characterized with IR and UV-Vis spectroscopies as well as based on the microanalytical data. The results showed that di-and tributyltin(IV) carboxylates prepared in general exhibit greater fungitoxicity than the organotin chlorides, the intermediate products and the free carboxylic acids. The organotin moiety plays an important role in deciding the antifungal activity of an organotin compound indeed true in our respect that the antifungal activity of tributyltin(IV) carboxylates is more active than dibutyltin(IV) carboxylates .

Mai de Meleda (keratoderma palmoplantaris transgrediens) is a rare autosomal recessive form of palmoplantar keratoderma characterized by hyperkeratosis of the palms and soles which appears soon after birth and progressively (progrediens) involves other areas (transgrediens) of the body skin. We report the case of a patient with mal de Meleda with three unusual facultative features, i.e. prominent knuckle pads, peculiar finger-nail anomalies and pseudo-ainhum on both fifth fingers. Four other members of the family are also affected by mal de Meleda.

The stability of the α-amylase enzyme has been improved from Aspergillus fumigatus using the immobilization method on a bentonite matrix. Therefore, this study aims to obtain the higher stability of α-amylase enzyme from A. fumigatus; hence, it is used repeatedly to reduce industrial costs. The procedures involved enzyme production, isolation, partial purification, immobilization, and characterization. Furthermore, the soluble enzyme was immobilized using 0.1 M phosphate buffer of pH 7.5 on a bentonite matrix, after which it was characterized with the following parameters such as optimum temperature, Michaelis constant (KM), maximum velocity V max , thermal inactivation rate constant (ki), half-life (t1/2), and the change of energy due to denaturation (ΔGi). The results showed that the soluble enzyme has an optimum temperature of 55°C, KM of 3.04 mg mL−1 substrate, V max of 10.90 μmole mL−1 min−1, ki of 0.0171 min−1, t1/2 of 40.53 min, and ΔGi of 104.47 kJ mole−1, while the immobilized enzyme has an optimum temperature of 70°C, KM of 8.31 mg mL−1 substrate, V max of 1.44 μmole mL−1 min−1, ki of 0.0060 min−1, t1/2 of 115.50 min, and ΔGi of 107.37 kJ mole−1. Considering the results, the immobilized enzyme retained 42% of its residual activity after six reuse cycles. Additionally, the stability improvement of the α-amylase enzyme by immobilization on a bentonite matrix, based on the increase in half-life, was three times greater than the soluble enzyme.

A series of dibutyl-, diphenyl-and triphenyltin(IV)