Excellent laundry detergent compatibility and high dehairing ability of the Bacillus pumilus CBS alkaline proteinase (SAPB)

Abstract

^Äëíê~Åí= The newly Tunisian soil-isolated bacterium, producing the alkaline proteinase termed SAPB that was already purified and characterized [1], was assigned as _~Åáääìë=éìãáäìë=CBS strain on the basis of biochemical properties and 16S rRNA gene sequencing. The maximum protease activity recorded after 24 h of incubation in an optimized medium at 37°C was 6,500 U/mL in shaking flask culture and 25,000 U/mL in fermentor. SAPB showed excellent stability and compatibility in laundry detergent retaining more than 98% of its initial activity after pre-incubation for 1 h at 40°C with Det, followed by OMO (97%), Dinol (94%), and Dixan (93%). Examination of various stained cloth pieces exhibited a remarkable efficiency in the removal of blood and chocolate stains. More interestingly, SAPB demonstrated powerful dehairing capabilities of hair removal from skin with minimal damage on the collagen and a nearly complete feather-degradation. Likewise, _~Åáääìë=éìãáäìë CBS effectively degraded feather-meal (98.5%), chicken feather (92%), goat hair (80%), and bovine hair (68%) whereas sheep wool under went less degradation. Keratin-degradation resulted in sulfhdryl group formation (0.95~3.91 µM). © KSBB hÉóïçêÇëW=^äâ~äáåÉ=éêçíÉáå~ëÉI=Bacillus pumilus=`_pI=ä~ìåÇêó=ÇÉíÉêÖÉåíI=ÇÉÜ~áêáåÖ=ÑìåÅíáçåI=âÉê~íáåJÇÉÖê~Ç~íáçå

The Bioengineering and Industrial Applications of Bacterial Alkaline Proteases: the Case of SAPB and KERAB

“…The non-treated enzyme was rapidly inactivated, losing about 50% of its initial activity after 2 months of incubation. Moreover, compared to the treated enzyme and in the absence of additives, 1% xylitol clearly enhanced SAPB stability during storage within the Det solid detergent (Jaouadi et al, 2009). In fact, after being incubated for 12 months at room temperature in the presence and absence of xylitol, the spray-dried enzyme retained 68 and 55% of its initial activity, respectively.…”

“…The findings from these assays revealed that the blood and chocolate stain removal levels achieved with the use of SAPB alone were more effective than the ones obtained with detergent (Det) alone. In fact, SAPB facilitated the release of proteinacious materials in a much easier way than the commercialized SB 309 protease (Jaouadi et al, 2009). Furthermore, the combination of SAPB and the Det detergent resulted in complete stain removal (Fig.…”

“…The findings indicated that spray-dried SAPB, from fermentor culture, lost about 3% of its original activity; lyophilized SAPB lost about 10% (Jaouadi et al, 2009). Several of the additives used during the spray drying and lyophilizing processes were noted to improve SAPB stability (Table 4).…”

“…A molecular approach was used to establish further support for the identification of the CBS and AB1 isolates. Two 16S rRNA gene fragments, namely 1,497 bp (Jaouadi et al, 2009) and 1541 bp (Jaouadi et al, 2010a), were amplified from the genomic DNA of the CBS and AB1 isolates, respectively, and then cloned and sequenced on both strands. The 16S rRNA gene sequences obtained were subjected to GenBank BLAST search analyses, which yielded strong homologies of up to 98 and 99% with those of several cultivated strains of Bacillus and Streptomyces, respectively.…”

“…Streptomyces rochei strain A -1 (GQ392058) .135] at pH 10 was noted to bring about a significant enhancement of 1.32 folds in SAPB production, which reached 6,500 U/ml under the optimal conditions used (pH 10.6 and 65°C), after 24 h of incubation at 37°C and 250 rpm (Jaouadi et al, 2009). In medium containing trace salts with feather as carbon and nitrogen source (g/l): NaCl, 0.5; KH 2 PO 4 , 0.5; K 2 HPO 4 , 0.5; KCl, 0.1; MgSO 4 ·7H 2 O, 1; and chicken feather meal, 10; at pH 9, KERAB production was observed to undergo a significant improvement, reaching a maximum of 9,500 U/ml under the optimal conditions used (pH 11.5 and 75°C) after 96 h of incubation at 30°C and 200 rpm (Jaouadi et al, 2010a).…”