Statistical Optimization of the production of protease from Bacillus sp. MSK-01 in submerged fermentation

2018 ◽  
Vol 23 (4) ◽  
Author(s):  
Kulwant Kaur ◽  
Sonica Sondhi ◽  
Palki Sahib Kaur

Protease has been in increasing demand in industries due to its hydrolytic nature. In industries, high yield of enzyme is required to meet the industrial need at a relatively cheaper cost. In the present study, the protease from Bacillus sp. MSK-01 was produced in large quantity by submerged fermentation. Statistical techniques including Plackett-Burman and Response surface methodology are useful tools for optimizing many parameters at a time and are used for increasing the protease production from Bacillus sp. MSK-01. 19 different parameters were chosen, out of which 15 factors had positive effect on protease yield. Four maximum influencing factors were peptone, magnesium sulphate, skim milk powder and casein were chosen to further increase the protease yield. 397.3 IU ml-1 of enzyme yield was obtained under optimized conditions which lead to 198 fold increase in the yield of protease from unoptimized condition. 

1972 ◽  
Vol 104 (12) ◽  
pp. 1985-1994 ◽  
Author(s):  
R. P. Jaques

AbstractDeposits of the nuclear-polyhedrosis virus of Trichoplusia ni (Hübner) and of the granulosis virus of Pieris rapae (Linnaeus) were largely inactivated within 10 days after sprays were applied to field plots. Deposits on plants retained in a growth room or in a greenhouse were inactivated but more slowly than those exposed to direct sunlight. Deposits on plants kept in the dark lost little activity indicating that exposure to light was responsible for inactivation.Activity of deposits of the viruses was extended substantially by addition of protectant materials to the sprays. The addition of charcoal mixed with skim milk powder, egg albumen, or brewer’s yeast resulted in a 3-fold increase in the period over which an LD50 of virus was maintained on the plants.


1988 ◽  
Vol 51 (8) ◽  
pp. 643-647 ◽  
Author(s):  
DONG K. JEONG ◽  
JOSEPH F. FRANK

The effect of fortifying skim milk with non-fat dried milk on growth and proteolysis of psychrotrophic bacteria was determined. Raw skim milk of 8.7% total solids was fortified to 10% and 12% total solids and pasteurized. Growth rates of proteolytic psychrotrophic bacteria were determined in these milks during incubation at 4°C. Proteolysis was determined by measuring the concentration of free amino groups throughout the incubation period. Seven of nine psychrotrophic isolates grew to greater numbers in the fortified milks during the early log phase of growth than they did in the unfortified milks. Growth stimulation was slight in most cases, however, one isolate exhibited a ten-fold increase in numbers when growing in the 10% solids fortified milk. The greatest increases in growth were observed when comparing unfortified milk to milk at 10% solids. Early log phase growth in 12% solids milk was often less than in 10% solids milk but still greater than in unfortified milk. All isolates exhibited increased proteolysis in the fortified milks within 48 h of incubation. These results indicate that increasing the solids content of skim milk with non-fat milk powder produces a microbiological growth medium more suitable for growth and protease production for selected psychrotrophic bacteria.


Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1600
Author(s):  
Dong-Hyun Lim ◽  
Andres Letona ◽  
Minjeong Lee ◽  
Dayoung Lim ◽  
Nam-Soo Han ◽  
...  

A probiotic powder of poor flowability with high dust content, prepared by spray drying reconstituted skim milk fermented with Lactobacillus rhamnosus GG (LGG), was granulated by fluidized-bed granulation (FBG). The effects of the addition of skim milk powder (SMP) as a fluidizing aid, and of simple moisture-activation with or without dehydration, were investigated with respect to the performance of the FBG process. A fine, poorly fluidizable LGG powder (Geldart Group C) could be fluidized and granulated, with a 4- to 5-fold increase in particle size (d4,3 = 96–141 μm), by mixing with SMP (30–50%), which has larger, fluidizable particles belonging to Geldart Group A. Moisture-activation after the mixing, followed by fluidized-bed dehydration with hot air to remove excess moisture, further improved the FBG; the yield of the granules increased from 42% to 61% and the particle size distribution became much narrower, although the average particle size remained almost the same (d4,3 = 142 μm). These granules showed a popcorn-type structure in scanning electron microscopy images and encapsulated a sufficient level of viable LGG cells (1.6 × 108 CFU g−1). These granules also exhibited much better flowability and dispersibility than the spray-dried LGG powder.


2021 ◽  
pp. 106757
Author(s):  
Jianfeng Wu ◽  
Simin Chen ◽  
Teng Wang ◽  
Hao Li ◽  
Ali Sedaghat Doost ◽  
...  

2021 ◽  
pp. 104997
Author(s):  
Sejeong Kim ◽  
Jae Yeon Joung ◽  
Daekyoung Kang ◽  
Nam Su Oh ◽  
Yohan Yoon

1983 ◽  
Vol 36 (1) ◽  
pp. 147-150 ◽  
Author(s):  
W. S. Thickett ◽  
N. H. Cuthbert ◽  
T. D. A. Brigstocke ◽  
M. A. Lindeman ◽  
P. N. Wilson

ABSTRACTResults are presented from six trials dealing with aspects of management on the cold ad libitum system of calf rearing using an acidified milk replacer containing over 600 g skim milk powder per kg.Thirty-six calves were housed in pens of six for each trial and were fed through a teat and pipeline from a storage barrel. Acidified milk replacer, pH 5·6, was mixed cold at 125 g/1 and made available ad libitum to 3 weeks. A rationed allowance was given daily, on a reducing scale, over the following 2 weeks with weaning completed at 35 days. A pelleted dry food containing 180 g crude protein per kg, together with water in buckets and barley straw in racks, was available ad libitum throughout. Each trial lasted 8 weeks. Results for the mean of the six cold ad libitum trials involving 216 calves were compared with the mean results of 10 conventional bucket-fed trials carried out separately at the same unit, involving 912 calves. All calves were purchased British Friesian male (bull) calves.Calves on the ad libitum system showed improved live-weight gains of 9·4 kg at 3 weeks, 8·8 kg at 5 weeks and 7·5 kg at 8 weeks, compared with the conventional system. The consumption of milk replacer powder was higher in ad libitum trials at 29·4 kg cf. 12·5 kg by bucket but intake of pelleted dry feed was lower on the ad libitum system at 50·7 kg cf. 71·3 kg to 8 weeks. Calf appearance scores were significantly improved on the ad libitum system which gave the main improvement in performance in the first 3 weeks.


1955 ◽  
Vol 53 (4) ◽  
pp. 387-397 ◽  
Author(s):  
P. H. R. Anderson ◽  
Doris M. Stone

SummaryEight explosive outbreaks of food poisoning, occurring in school canteens in England during 1953 and affecting 1190 known cases, are described. The clinical features were characteristic of the toxin type of illness. No deaths occurred.The food causing all of these outbreaks was prepared from spray-dried skim milk powder. It was not subsequently heat-treated and was usually consumed 3–4 hr. after preparation.The spray-dried milk powder proved to contain a high content of bacteria, including large numbers of Staph. aureus, of a phage pattern often associated with food poisoning. The assumption was therefore made that these outbreaks were caused by staphylococcal enterotoxin.Because the food was often consumed within 3–4 hr. of reconstitution of the milk powder—before, in fact, the staphylococci had had time to grow—it is concluded that the poisoning must have been due mainly to pre-formed toxin.Consideration is given to the opportunities for the formation of toxin in a spray-drying plant, and reasons are brought forward for believing that it is formed mainly in the balance tank where the warm milk is kept, sometimes for several hours, before passing into the final drying chamber.The processing of the milk and the precautions for preventing contamination of the finished product are discussed.


1998 ◽  
Vol 12 (2) ◽  
pp. 97-105 ◽  
Author(s):  
Binita Rani ◽  
N. Khetarpaul

A probiotic fermented PCMT food mixture was developed by fermentation of an autoclaved and cooled slurry of pearl millet flour, chickpea flour, skim milk powder and fresh tomato pulp (PCMT 2:1:1:1, w/w) with Lactobacillus acidophilus (105 cells/ml), a probiotic organism at 37°C for 24 h. Such a fermented mixture inhibited the growth of pathogenic organisms, namely Shigella dysenteriae, Salmonella typhosa and E. coli. A significant decline in pH with a corresponding increase in titratable acidity due to probiotic fermentation occurred in the developed food mixture. Feeding of the freshly developed fermented. mixture to mice suffering from E. coli induced diarrhoea, could help to arrest diarrhoea, reduce moisture, protein and ash contents in their faeces. The counts of lactobacilli increased whereas those of E. coli decreased remarkably in the faeces of mice from the 3rd day of the feeding trial till the end of experimental period. The beneficial effect of probiotic feeding may be due to antimicrobial substances produced by L. acidophilus, which might have neutralized the enterotoxins from E. coli. The cost of one 200 ml glass full of this probiotic drink is no more than one rupee.


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