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Objective:To investigate the microbial contamination status of Chinese herbal pieces from Guangxi regions and provide reference for the microbial limit standard. Methods:According to Chinese Pharmacopoeia (2015 edition), the herbal pieces were analyzed for the total number of aerobe microbial, yeasts, molds, thermophilic bacteria and bile-resistant gram-negative bacteria,and salmonella was also detected. Results:In 90 batches of Chinese herbal pieces,the lg average value of the total number of aerobe microbial was 3.7,and that of the total yeasts and molds was 1.7,that of thermophilic bacteria was 0.9 and that of bile-resistant gram-negative bacteria was 1.1,and Salmonella was not detected out. There were statistically significant differences (P < 0.05) in the microbial contamination levels of herbal pieces with different processing techniques and packaging materials. Conclusion:According to different processing methods and administration, microbial limit standard should be established for classification in order to guide the standardized production of Chinese herbal pieces and improve their quality gradually.
ABSTRACT
@#Aims: This research focused on the selection of potential strains especially bacteria that can grow effectively in palm kernel cake (PKC) and produce high amount of thermostable and solvent tolerant (TS-OST) lipase. The work involved the exploration of renewable PKC as potential fermentation medium for discovery to novel TS-OST lipase that would have excellent tolerance and activity in presence of organic solvents with high temperatures for industrial applications.Methodology and results: Using palm kernel cake (PKC) as source of thermophilic bacteria, 53 bacterial strains were found survived at temperature 65 °C. However, after subcultured several times, only 17 strains were found as pure thermophilic strains. Preliminary screening both qualitative and quantitative was performed to all 17 potential thermophilic bacterial strains and showed that only 11 purified thermophilic strains are lipase producer. Strain PKC-P1 produced highest enzyme activity (11.13 U/g), followed by PKC-P13 and PKC-C9. The lowest enzymeactivity was lipase produced byPKC-C10 (0.76U/g). Strain PKC-P1 has been classified as Gram negative bacteria and identified as Bacillus smithiistrain PKC_P1.Conclusion, significance and impact of study: PKC as a by-product of oil palm industry consistsof many nutrients that can give benefits towards industry and can be utilized in order to produce enzymes like lipases. From these results, it could be concluded that this lipase stable at temperature 65 °C and pH 7 and may be a potential candidate to be used in a variety of biotechnological applications. This finding revealed that a bacterial strain obtained from oil-rich environment which is PKC through isolation process has potential as a source of more economical enzyme to be applied in biotechnology industr
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The diversity of thermophilic bacteria was investigated in four hot springs, three salt marshes and 12 desert sites in Morocco. Two hundred and forty (240) thermophilic bacteria were recovered, identified and characterized. All isolates were Gram positive, rod-shaped, spore forming and halotolerant. Based on BOXA1R-PCR and 16S rRNA gene sequencing, the recovered isolates were dominated by the genus Bacillus (97.5%) represented by B. licheniformis (119), B. aerius (44), B. sonorensis (33), B. subtilis (subsp. spizizenii (2) and subsp. inaquosurum (6)), B. amyloliquefaciens (subsp. amyloliquefaciens (4) and subsp. plantarum (4)), B. tequilensis (3), B. pumilus (3) and Bacillus sp. (19). Only six isolates (2.5%) belonged to the genus Aeribacillus represented by A. pallidus (4) and Aeribacillus sp. (2). In this study, B. aerius and B. tequilensis are described for the first time as thermophilic bacteria. Moreover, 71.25%, 50.41% and 5.41% of total strains exhibited high amylolytic, proteolytic or cellulolytic activity respectively.
Subject(s)
Bacillaceae/classification , Bacillaceae/isolation & purification , Gram-Positive Rods/classification , Gram-Positive Rods/isolation & purification , Hot Springs/microbiology , Soil Microbiology , Water Microbiology , Biodiversity , Bacillaceae/genetics , Bacillaceae/radiation effects , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Gram-Positive Rods/genetics , Gram-Positive Rods/radiation effects , Molecular Sequence Data , Morocco , Phylogeny , /genetics , Sequence Analysis, DNA , Spores, Bacterial/cytologyABSTRACT
Studies on lipase production were carried out with a bacterial strain (Bacillus sp LBN 2) isolated from soil sample of hotspring of Arunachal Pradesh, India. The cells were cultivated in a mineral medium with maximum production at 1% groundnut oil. The optimum temperature and initial medium pH for lipase production by the organism were 50ºC and 9.0 respectively. The molecular mass was found to be 33KDa by SDS PAGE. The optimal pH and temperature for activity were 10 and 60ºC respectively. The enzyme was found to be stable in the pH range of 8-11 with 90% retention of activity at pH 11. The enzyme retained 90% activity at 60ºC and 70% of activity at 70ºC for 1h. The lipase was found to be stable in acetone followed by ethanol. The present findings suggested the enzyme to be thermophilic alkaline lipase.