A selective medium was used to isolate a bacterium (Bacillus species NRRL B-3881) that produced extracellular alkaline amylase in an alkaline medium (pH 9.5). Maximal enzyme yield was obtained in an aerated medium after 21 hr at 36 C. The enzyme was purified 18-fold by ultrafiltration and ammonium sulfate precipitation. Three active isoenzymes (one major and two minor) of alkaline amylase were detected by disc electrophoresis in polyacrylamide gel. The enzyme was only 12% inactivated by 20 mM ethylenediaminetetraacetic acid after 1 hr at pH 9.2 and 32 C. The optimal temperature was 50 C at pH 9.2, and the optimal pH was 9.2 at 50 C. The enzyme was stable between pH 7.5 and 10. It had an endomechanism of substrate encounter. The products produced from amylose and amylopectin had the ,B-configuration. Cyclomaltoheptaose was hydrolyzed to maltotriose, maltose, and glucose. The main final product produced from amylose and amylopectin was ,8-maltose; the other final products were maltotriose and small quantities of glucose and maltotetraose. The predominant product at early stages of hydrolysis was maltotetraose; other products were maltose through maltonanaose. Amylases from plants, animals, and microorganisms have been studied since enzymes were first discovered. However, until recently all of the amylases studied had pH optima in the acid or neutral range. Sather (12) described an amylase with a pH optimum of 8.0 in the crab Metapograpsus messor. Recently, Robyt and Ackerman (8) characterized a maltotetraose-producing amylase from Pseudomonas stutzeri; this enzyme had a broad pH-activity eurve with an optimum at 8.0. Also, alkaline amylase (glycoside hydrolase, EC 3.2.1.-)-producing Bacillus species have been reported (Rikagaku Kenkyusho,
An alkaline-amylase-producing, alkalophilic bacillus, NRRL B-388 1, was characterized and compared with Bacillus sp. ATCC 21591 and Bacillus alcalophilus Vedder strain NCTC 4.553 (=ATCC 27647), which is here designated as the type strain of B. Irlcalophilus. All three strains contained. motile, gram-positive rods with rounded ends and swollen, clavate sporangia with oval, terminal to subterminal endospores. All three strains grew in soybean broth; were facultatively anaerobic; hydrolyzed starch, gelatin, and casein; reduced methylene blue; and fermented the 'following carbohydrates without gas production: sucrose, D-glucose, lactose, maltose, D-mannitol, D-xylose, Larabinose, glycerol, sorbitol, and salicin. None produced acetylmethylcarbinol, indole, urease, or crystalline dextrins. Bacillus sp. ATCC 2 159 1 and Bacillus sp. NRRL B-3881, but not NCTC 4553, reduced nitrate t o nitrite, utilized citrate, and grew well in 12% NaCl and slowly in 15% NaC1. B. alcalophilus NCTC 4553 did not grow in 5% NaC1. In our opinion, these differences are sufficient to justify the establishment of a separate subspecies for ATCC 21591, NRRL B-388 1, and similar strains. We propose the name B. alcalophilus subsp. halodurans as the name for this new subspecies. The name of the type subspecies, which contains the type strain, NCTC 4553, is B. alcalophilus subsp. alcalophilus Vedder. NRRL B-3881 is designated as the type strain of B. alcalophilus subsp. halodurans and is available from the Northern Regional Research Laboratory. It has also been deposited in the American Type Culture Collection under the number 275.57.
Fruits and vegetables are important constituents of the diet and provide significant quantities of nutrients, especially vitamins, minerals and fiber. Beetroots (Beta vulgaris L.) are a rich source of potent antioxidants and minerals including magnesium, sodium and potassium. It contains betaine, which is important for cardiovascular health. Beetroots are low in calories (about 45 Kcal per 100 g) and have zero cholesterol. The study was conducted to improve the nutritional qualities of cookies with incorporation of different levels of beetroot powder i.e. 0, 5, 7, 10, 15 and 20 %, and examined for its physical and chemical composition. The proximate composition of cookies enriched with beetroot powder from 5 to 20% indicated that protein was increased from 7.39 to 9.12 %, crude fibre 0.95 to 1.90 % and ash content 0.93 to1.89 %. The incorporation of beetroot powder in cookies lowered the lightness (L*) and yellowness (b*) but increased redness (a*) of cookies. The hardness of the cookies was increased with increasing the level of beetroot powder. Sensory evaluation of cookies concluded that the cookies prepared with addition of 10% beetroot powder were more acceptable as compared to others.
The thermoacidophilic amylases produced by Bacillus acidocaldurius strains have very acid pH optima as expected but the temperature optima are not much higher than that of Bacillus amyloliquefaciens which is a mesophile and they are not as high as that of Bacillus lichenformis which is a facultative thermophile. Alkaline amylases produced by Bacillus alcalophilus subsp. haloduruns strains which are insensitive to sequestering agents and stable at high temperatures, expand the range of potential amylase uses to conditions of high alkalinity. Comparison of the pH and temperature profiles of different Bacillus species amylases demonstrates that amylases have evolved in a single genus in such a way that they can function optimally at almost any pH value and temperature. The properties of these amylases reflect extensivemicrobial adaptation and demonstrate the wide variety of enzymes potentially available for biochemical processing. lsolierung und Charakterisierung ungewohnlichet bakterieller Amylasen. Die von Bacillus acidocaldarius gebildeten thermoacidophilen Amylasen besitzen wie erwartet pH-Optima im sehr sauren Bereich, jedoch liegen die Temperatur-Optima nicht vie1 hoher als das Optimum der Amylase aus Bacillus amyloliquefaciens, der mesophil ist, und sie sind nicht so hoch wie das Optimum der Amylase aus Bacillus lichmijbrmis, welcher fakultativ thermophil ist. Alkalische Amylasen aus Bacillus ulcalophilus subsp. hulodurans-Stammen, welche unempfindlich gegen komplexbildende Agentien und stabil gegen hohe Temperaturen sind, dehnen den Anwendungsbereich von Amylasen auf Bereiche hoher pH-Werte aus. Ein Vergleich der pHund Temperaturprofile der verschiedenen Bacillus-Amylasen zeigt, daljdieEvolutionineinemeinzigenGendergestaltstattgefunden hat, daB die Amylasen optimal bei fast allen pH-und Temperaturwerten wirksam sind. Die Eigenschaften dieser Amylasen spiegeln die extreme Anpassungsfahigkeit von Mikroorganismen wider und zeigen die grolje Bandbreite von Enzymen, die potentiell fur biochemische Prozesse verfugbar sind. Starch/Starke 31 (1979) Nr. 5 , S. 166-171
The present investigation was carried out with the objectives to develop a low calorie with high nutritional quality having good acceptability. The results showed that best quality of sugar free aonla candy was made from (10%) aspartame sugar free materials and aonla segments. In comparison to candy had minimum acidity in standard (0.61%) and maximum in aspartame aonla candy (0.76%). Maximum ascorbic acid was in standard aonla candy (230.6mg/100g) and minimum in Sucralose aonla candy (85.4mg/100g). Tannin content was recorded maximum (1.60%) in aspartame candy and minimum was (1.48%) in standard candy. The maximum color contain was recorded in standard candy (L-28.53 a-5.55 b-16.88) followed by (L-28.42 a-8.09 b-13.82) aspartame candy. Thus it was concluded that 10% aspartame aonla candy could be considered the best from nutritional, cheapest, and organoleptic point of view. Hence low cost nutritionally balanced low calorie aonla candy for diabetic patient could be developed at house hold or commercial level.
Mucor miehei was grown in submerged culture at 30, 37, 40, 42.5, 45, and 48 °C. Maximum growth yield occurred at 48 °C.The effect of temperature on spore germination was examined. No spores germinated within 8 h at temperatures below 36.7 °C or above 53.5 °C. The optimum temperature for spore germination was 45 °C.Growth occurred at the marginal temperatures of 20 °C and 25 °C only when the spores were pre-germinated at 37 °C
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