Screening and Identification of Thermotolerant and Osmotolerant Bacillus amyloliquefaciens BKHE Isolated from Kinema of Eastern Nepal for Alkaline Protease Production

Table 2

Phenotypic features of selected isolate and comparison with closely related species based on BLAST result.

Tests	BKHE	B. amyloliqueficiens [18]	B. velezensis [40]	B. valismortis [18]
Colony characteristics
Colony form	Circular
Elevation	Slightly raised
Margin	Undulate
Texture	Slightly viscous
Opacity	Opaque
Surface	Smooth
Chromogenesis	Dirty white		Creamy white
Diameter (cm)	0.3–0.4
Gram staining	+	+	+	+
Shape of cell	Rod	Rod	Rod	Rod
Size of cell	3–5 um		1.5–3.5 um
Spore staining	+	+	+	+
Spore position	Subterminal
Spore shape	Ellipsoidal	Ellipsoidal	Ellipsoidal	Ellipsoidal
Growth at temperature
30	+		+	+
40	+	+	+	+
45	+		+
50	+	±	−	+
60	−	−	−
Nacl tolerance
1%	+		+
2%	+	+	+	+
5%	+	+	+	+
Growth at Ph
4.5	−	±
6	+	+	+	+
7.2	+	+	+	+
8	+	+	+
9.5	+	+	+
Indole production	−	−	−
Voges-Proskauer	+	+	+	+
Hydrogen sulfide	−		+
Arginine dihydrolase	−	−	−
Motility	+	+	+	+
Nitrate reduction test	+	±	+	+
Catalase	+		+	+
Oxidase	−	−	+	+
Citrate utilization	+	±		+
Malonate utilization	−	−
Acid from
Lactose	−	±	+	−
Xylose	−	±	+	+
Maltose	+	+	+	+
Fructose	+	+	+	+
Dextrose	+	+	+	+
Galactose	−	−	−	+
Raffinose	−	+	+
Trehalose	+	±	+	+
Melibiose	−		−	+
Sucrose	+	+	+	+
L-arabinose	−	±	+	+
Mannose	−	±	+	+
Inulin	−		−
Sodium gluconate	−		−
Glycerol	+	+	+
Salicin	−	+	+	+
Dulcitol	−	−	−
Inositol	−		+
Sorbitol	+	±	+	+
Mannitol	+	+	+	+
Adonitol	−	−	−
Arabitol	−		−
Erythritol	−	−	−
α-methyl-D-glucoside	−		+
Rhamnose	−	−	−	+
Cellobiose	+	+	+	+
Melezitose	−		−
α-methyl-D-mannoside	−		−
Xylitol	−		−
D-arabinose	−		−
Sorbose	−		−
Hydrolysis of
Urea	−	−		−
Gelatin	+	+	+
Lipid (tributyrin)	+
Casein	+	+	+	+
Cellulose	−
Starch	+	+	+	+
ONPG	−	±	+
Esculin	+	+
Resistance to antibiotics	AMP, CXM, AMC, CTX
Sensitive to antibiotics	CIP, GEN, TE, MO, LE, AZM, E, VA,RIF

AMP–ampicillin (10 mcf); CXM–cefuroxime (30 mcf); AMC–amoxicillin (10 mcf); CTX–cefotaxime (30 mcf); CIP–ciprofloxacin (30 mcf); GEN–gentamycin (10 mcf); TE–tetracycline (30 mcf); MO–moxifloxacin (5 mcf); LE–levofloxacin (5 mcf); AZM–azithromycin (15 mcf); E–erythromycin (15 mcf); VA–vancomycin (30 mcf); RIF–rifampicin (5 mcf).