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The alkaline conditions for extraction of natural dye from Henna leaves were optimized and the resulting extract was used to further optimize its dyeing conditions on cotton by exhaust method. Dyeings without any mordant were compared with those obtained with premordanting and postmordanting with alum and iron. It was found that dyeings produced with alkaline extracts of Henna leaves have better colour strength than the dye extracts obtained in distilled water. Furthermore, dyeings with alkaline extracts have moderate to good fastness properties and that mordanting did not result in any significant improvement in fastness properties. Finally, in comparative studies between synthetic and this natural dye, it was inferred that natural dye has good potential to act as co-partner with synthetic dye.

A natural dye is extracted from turmeric and used to dye cotton at different dyeing conditions. Then the fastness properties of the dyeings with different dyeing techniques are compared. The dye is found to have good saturation and rubbing fastness, but poor washing and light fastness properties on cotton, when applied without any mordant. When dyeing is implemented with mordants, washing and light fastness properties show improvement while rubbing fastness exhibits deterioration.Finally, comparative studies between natural and synthetic reactive dyes reveal that the natural dye has the potential to act as a co-partner with reactive dyes with a few compromises.

Chemical modification of carboxyl groups of glucoamylase from a mesophilic fungus, Fusarium solani , was carried out using ethylenediamine as nucleophile in the presence of water-soluble 1-ethyl-3(3-dimethylaminopropyl)carbodiimide. Modification brought about a dramatic enhancement of catalytic activity and thermal stability of glucoamylase. Temperature and pH optima of ethylenediamine-coupled glucoamylase (ECG) increased as compared with those of native enzyme. The specificity constant (kcat/Km) of native, ECG-2, ECG-11, and ECG-17 was 136, 173, 225, and 170, respectively, at 55 °C. The enthalpy of activation (ΔH*) and free energy of activation (ΔG*) for soluble starch hydrolysis were lower for the chemically modified forms. All of the modified forms werestable at higher temperatures and possessed high ΔG* against thermal unfolding. The effects of α-chymotrypsin and subtilisin on the modified forms were activating as compared with native. Moreover, denaturation of ECG-2, ECG-11, and ECG-17 in urea at 4 mol·L–1also showed an activation trend. A possible explanation for the thermal denaturation of native and increased thermal stability of ECG-2, ECG-11, and ECG-17 at higher temperatures is also discussed.

Thermostable enzymes are currently being investigated to improve industrial processes of starch saccharification. A novel glucoamylase was purified to electrophoretic homogeneity from the culture supernatant of Fusarium solani on a fast protein liquid chromatographic system (FPLC). The recovery of glucoamylase after gel filtration on FPLC was 31.8% with 26.2-fold increase in specific activity. The enzyme had a molecular mass of 40 kDa by SDS-PAGE and 41 kDa by gel filtration. The glucoamylase exhibited optimum activity at pH 4.5. The Kcat and Km were 441/min and 1.9 mg/ml, respectively, for soluble starch, specificity constant (Kcat/Km) was 232. The enzyme was thermally stable at 50 °C and retained 79% activity after 60 min at this temperature. The half-life of the enzyme was 26 min at 60°C. The enzyme was slightly stimulated by Cu2+ and Mg2+ and strongly inhibited by Hg2+, Pb2+, Zn2+, Ni2+ and Fe3+.

The present investigation deals with purification and thermal characterization of an acid invertase produced by Fusarium solani in submerged culture. The maximum enzyme activity (9.90 U mL(-1)) was achieved after 96 h of cultivation at pH 5.0 and 30 degrees C in a basal medium containing molasses (2%) as the carbon and energy source supplemented with 1% peptone. Invertase was purified by ammonium sulfate fractionation and column chromatography on DEAE-cellulose and Sephadex G-200. The purified enzyme was proven to be homogeneous by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The molecular mass of the enzyme was 65 kDa. The optimum pH and temperature for activity were 2.6 and 50 degrees C, respectively. The Km value for sucrose was 3.57 mM with an activation energy of 4.056 kJ mol(-1). Enthalpies of activation (DeltaH) were decreased while entropies (DeltaS) of activation increased at higher temperatures. The effects of alpha-chymotrypsin and 4 M urea were tetraphasic with periodic gain and loss of enzyme activity. A possible explanation for the thermal inactivation of invertase at higher temperatures is also discussed.

Deferiprone (1, 2 dimethyl-3-hydroxypyrid-4-one) is considered to be the standard iron chelator. Pharmacokinetic studies of generic formulations are required in local condition before placed on the market. High performance liquid chromatographic (HPLC) method was used for quantification of deferiprone in human plasma using UV/VIS detector. Chromatographic separation was carried out on C(18) column, with a mobile phase of methanol-buffer (18:82, v/v), pH 3.5, and caffeine was used as an internal standard. The calibration curve was linear over the range 0.25-10 μg/mL in human plasma (R(2) = 0.9994). After oral administration of deferiprone (500 mg) to human, the plasma concentration-time curve of deferiprone was conformed to two-compartment open model. The deferiprone plasma concentration showed a rapid absorption and average area under the plasma concentration-time curve (AUC) of deferiprone was 17.0 ± 1.23 h.μg/ml. Average absorption and elimination half-life values of deferiprone of 24 volunteers were 0.62 ± 0.12 and 2.65 ± 0.43 hours. This study confirms the rapid absorption of deferiprone in humans. AUC was similar to that previously reported but C(max) was slightly lower than that stated in the literature.

Solid-state cultivation of Fusarium solani was carried out for enhanced production of glucoamylase (GA) using different substrates like wheat bran, rice bran, green gram bran, black gram bran and maize bran. The SSF medium containing wheat bran as a substrate yielded the highest enzyme activity. The physical and chemical parameters were optimized. Maximum enzyme activity (61.35±3.69) U/g of dry wheat bran was achieved under optimum growth conditions. The optimum conditions were fructose as carbon and energy additive 1 % (by mass), urea as nitrogen additive 1 % (by mass), initial moisture content of solid substrate 70 % (by mass per volume), incubation period 96 h, inoculum size 15 % (by mass per volume) having 10^6–10^7 spores/mL, incubation temperature (35±1) °C and pH=5.0. It was further observed that the addition of surfactants caused a decrease in enzyme biosynthesis by F. solani in SSF of wheat bran under optimum process conditions., Uzgojem gljive Fusarium solani fermentacijom na krutoj podlozi povećana je proizvodnja glukoamilaze (GA) primjenom različitih supstrata kao što su pšenične i rižine posije, te posije zelene soje, crne soje i kukuruza. Najveća aktivnost enzima dobivena je uporabom podloge od pšeničnih posija. Optimirani su fizikalni i kemijski parametri i pri optimalnim uvjetima rasta postignuta je maksimalna aktivnost enzima od (61,35±3,69) U/g suhih pšeničnih posija. Optimalni uvjeti bili su: 1 % (m/V) fruktoze kao izvora ugljika i energije, 1 % (m/m) uree kao izvora dušika, 70 % (m/V) početnog udjela vlage u krutoj podlozi, vrijeme inkubacije u trajanju od 96 h, 15 % inokuluma (m/V) s 10^6-10^7 spora/mL, temperatura inkubacije (35±1) °C i pH=5,0. Dodatkom površinski aktivnih tvari smanjila se biosinteza enzima proizvedenog fermentacijom pri optimalnim uvjetima na podlozi od pšeničnih posija s pomoću gljive F. solani.

Purified glucoamylase (GA) from Fusarium solani was chemically modified by cross-linking with aniline hydrochloride in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) for 1 [aniline-coupled glucoamylase-1 (ACG-1)], 7 (ACG-7), and 13 min (ACG-13). The aniline coupling of GA had a profound enhancing effect on temperature, pH optima, and pK (a)'s of active site residues. The specificity constants (K (cat)/K (m)) of native, ACG-1, ACG-7, and ACG-13 were 136, 244, 262, and 208 at 55 degrees C for starch, respectively. The enthalpy of activation (DeltaH*) and free energy of activation (DeltaG*) for soluble starch hydrolysis were lower for the chemically modified forms compared to native GA. Proteolysis of ACGs by alpha-chymotrypsin and subtilisin resulted in activation.

Saccharopine and 2-aminoadipic acid have been identified in eleven plant species belonging to nine families. The amino acids have been isolated from green parts of the plants using ion-exchange chromatography and preparative high voltage electrophoresis, and in three cases the identification was supported by mass spectroscopy. Mild conditions were used during the isolation to avoid lactamization, and the contents of saccharopine and 2-aminoadipic acid have been determined semiquantitatively. The significance of the occurrence of the two amino acids with regard to lysine metabolism is briefly discussed.