ABSTRACT
Aims@#The aim of this study was to screen lactic acid bacteria (LAB) isolates with probiotic properties for tilapia (Oreochromis niloticus) from the intestines of mackerel and to analyze its ability to produce hydrolase enzymes (amylase, protease, cellulase and lipase).@*Methodology and results@#Ten samples of mackerel were collected from the Fish Auction Place, Lewoleba, Nubatukan District, Lembata Regency, East Nusa Tenggara Province, Indonesia. The process for screening were antimicrobial activity, pH tolerance test of 1, 3 and 5, bile salt concentrations of 2.5%, 5% and 7.5%, and water salinity (0.5%, 3.5% and 6.5%). The autoaggregation and semi-qualitative test of hydrolase enzymes were also carried out. In total, 21 LAB isolates were derived from mackerel intestines. Isolates that have the stronger ability to inhibit the pathogen Aeromonas hydrophila ATCC 7966 are KBP 3.3, KBP 3.3.1 and KBP 6.3, while KBP 1.3, KBP 1.1.1 and KBP 3.3.1 were able to inhibit Streptococcus agalactiae ATCC 13813. The LAB isolates that survived at the tested pH were KBP 3.3.1, KBP 3.3, KBP 1.1.1 and KBP 1.3. Results also suggest that the four isolates were tolerant to bile salt concentrations and water salinity with good survival rates (>94.7%) and had proteolytic, lipolytic and cellulolytic activities. The isolates KBP 3.3, KBP 3.3.1 and KBP 1.1.1 were identified as Weissella confusa 6250, while the isolate KBP 1.3 was identified as W. confusa C5-7.@*Conclusion, significance and impact of study@#The characteristics of four selected isolates indicate their potential as a probiotic. These potential probiotic isolates can be applied directly to fish by utilizing microencapsulation technology or adding to the feed.
Subject(s)
Lactobacillales , Perciformes , IndonesiaABSTRACT
@#Aims: The objective of this research was to isolate caffeine-degrading bacteria from coffee pulp waste in Indonesia andcharacterize their caffeine degradation activity.Methodology and results: The caffeine-degrading bacteria were isolated from coffee pulp wastes of Coffea arabicaand C. canephora. These isolates were selected based on their caffeine degradation activity. The identification andbiochemical properties of the best isolate were conducted via 16S rDNA sequence analyses and by using the Microbactkit. Meanwhile, caffeine degradation activity of this bacteria was analyzed by using LC-MS/MS. The results indicatedthat fourteen bacterial isolates were able to degrade caffeine. The highest caffeine degradation activity was performedby isolate KRM9 at the rate of 99.26 ± 0.01%, on a caffeine medium after 24 h of incubation. Based on the 16S rDNAanalyses, the KRM9 isolate was identified as Pseudomonas monteilii. Till present, this species has not been reported asa caffeine-degrading bacterium. However, LC-MS/MS analysis indicated that caffeine was degraded by P. monteiliiKRM9 and theobromine was not the secondary metabolite of caffeine degradation.Conclusion, significance and impact of study: Pseudomonas monteilii KRM9 was detected as a new isolate ofcaffeine-degrading bacteria. This bacterium can be introduced as an agent to degrade caffeine from coffee pulp waste. Itis expected that further research can be conducted on the overall mechanism of caffeine degradation by P. monteiliiKRM9
ABSTRACT
Aims: The objective of the research was to get the potential cellulolytic bacteria which was caffeine tolerance from Indonesian coffee pulp waste. Methodology and results: The cellulolytic bacteria were isolated from coffee pulp wastes of Coffea arabica and C. canephora. These isolates were selected based on their cellulose hydrolysis, CMCase activity, and caffeine tolerance. The density of cellulolytic bacteria of C. arabica pulp waste was 4.7 ± 3.5 × 106 CFU/g, and that of C. canephora pulp waste was 1.5 ± 1.5 × 106 CFU/g. Among 61 cellulolytic bacterial isolates, 24 isolates formed clear zones on CMC medium with Gram iodine flooding. Three isolates (CRM10, CRM1, and CRM12) from C. canephora pulp waste had the highest cellulolytic activity. Based on the CMCase activity, it was indicated that an isolate of CRM10 showed the highest CMCase activity with 3.38 ± 0.65 U/mL. This bacteria had tolerance ability to caffeine until 0.4% on nutrient agar medium. Isolates of CRM10 had similarity to Bacillus subtilis based on 16S rDNA sequence. Conclusion, significance, and impact of study: CRM10 was identified as Bacillus subtilis and considered as a potential isolate to degrade cellulose of coffee pulp waste that contained caffeine. .
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Objective: To isolate, characterize and evaluate toxicity of Bacillus sphaericus (B. sphaericus) from beach area of Lombok Island. Methods: Soil was collected from determined locations and suspended in sterile physiological saline water. After heat shock was applied, suspension was spread on NYSM agar medium. Colonies grown were then observed and isolated. Colony, cell morphology, and biochemical/physiological characteristics were tested and compared to B. sphaericus 2362 as standard. Initial toxicity testing was done against three species of mosquito larvae (Culex quinquefasciatus, Anopheles aconitus and Aedes aegypti) and isolates that showed more than 50% larvae killing will be assayed to obtain LC