Discovering the thermophiles microbial diversity of Malaysian hot spring in Ulu Slim, Perak

@#Aims: Hot springs are major sources of useful thermophilic microbes. Our study therefore aimed at documenting and analysing the microbial communities at Ulu Slim hot spring in Perak, Malaysia, for bacteria with beneficial enzymes for industrial applications. Methodology and results: The study sampled water and sediment materials from the Ulu Slim hot spring at two sublocations of different temperatures, 45 °C and 72 °C. The samples were then extracted for genomic DNA, followed by paired-end metagenome sequencing using prokaryotic-conserved, locus specific primers for 16S rRNA V3 and V4 domains, and Illumina MiSeq (2  300) sequencing platform. Raw data were optimized using Trimmomatic and FLASH, followed by operational taxonomy units (OUT) determination and clustering. 16S rRNA gene sequences were then analysed against Silva (SSU123) 16S rRNA gene databases for phylum and genus classifications. Data analysis showed relevant alignment of present bacteria phyla against data from a previous study on Ulu Slim hot springhead, though the different sample temperatures significantly affected phylum and genus composition. Our study also confirmed the presence of a site-specific genus, Fervidobacteria, which are anaerobic bacteria with a unique ability in degrading keratin. Conclusion, significance and impact of study: The study further completes and complement the findings on microbial communities at the Ulu Slim hot spring. The findings help to reveal the associations between microbes and environmental factors at thermophilic locations, as well as potential thermostable enzymes like lipase and amylase that can be isolated from thermophilic sample as they are indispensable for industry.

Fermented beverage based on water-soluble soybean extract / Bebida fermentada à base de extrato hidrosolúvel de soja

Functional foods are those that, beyond basic nutrition, promote health benefits. This study aimed to produce a fermented beverage from a water-soluble soybean extract and low-lactose semi-skimmed milk. The beverage was prepared using a blend (v/v) containing 62% water-soluble soybean extract, 33% low-lactose semi-skimmed milk, and 5% of an inoculum containing Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus. The fermentation was carried out with monitoring of the lactic acid bacteria (LAB) counts, pH, and titrable acidity (% lactic acid). The consumption-ready fermented beverage was added of strawberry syrup and posteriorly characterized by its centesimal composition and sensory attributes as appearance, aroma, flavour, texture, overall impression, and purchase intent. Additionally, the LAB count and presence of pathogens in the final product were evaluated. After 14 h of fermentation, the refrigerated product presented L. bulgaricus and S. thermophilus counts of 8.5 × 103 and 7.4 × 107 CFU/mL, respectively. The product contained 14.93% carbohydrates, 0.76% fats, 0.96% ash, 22.76% totalsolids, and 2.19% protein. Because the product did not present any pathogens, it was adequate according to the standards of microbiological safety determined by Brazilian legislation. Regarding the sensory evaluation, the panelists assigned a mean score of 7.0 for the attributes evaluated, indicating 'liked moderately' to the drink. In addition, 61% of the evaluators responded that they 'certainly or probably would buy' the product if it were available on the market.

Alimentos funcionais são aqueles que, além da nutrição básica, promovem benefícios à saúde. Este trabalho teve como objetivo produzir uma bebida fermentada a partir de extrato hidrosolúvel de soja (EHS) e leite semidesnatado com baixa lactose. A bebida foi preparada utilizando uma mistura (v/v) contendo 62% de EHS, 33% de leite semidesnatado com baixa lactose e 5% de inóculo contendo Lactobacillus delbrueckii subsp. Bulgaricus e Streptococcus salivarius subsp. Thermophilus. A fermentação foi acompanhada durante 14 horas, através das contagens das bactérias ácido lácticas, pH e a acidez titulável (% de ácido láctico). A bebida fermentada pronta para consumo foi adicionada de uma calda de morango e caracterizada por sua composição centesimal, bem como por avaliação sensorial para os atributos: aparência, aroma, sabor, impressão global e intenção de compra. Além disso, a contagem das bactérias lácticas e presença de patógenos no produto foi avaliada. Após 14 horas de fermentação, o produto final refrigerado apresentou contagens de 8,5x103 UFC/mL e 7,4x107 UFC/mL para as bactérias L. bulgaricus e S. thermophilus respectivamente. O produto apresentou 14,93% de carboidratos, 0,76% de gordura, 0,96% de cinzas, 22,76% de sólidos totais e 2,19% de proteína. O produto não apresentou quaisquer patógenos, portanto, foi adequado aos padrões determinados pela legislação brasileira quanto à segurança microbiólogica. Com relação à avaliação sensorial, os provadores atribuíram em média nota 7,0 para todos os parâmetros avaliados, indicando que "gostarammoderadamente" da bebida. Ademais 61% dos avaliadores apontaram que "certamente ou provavelmente comprariam" o produto se estivesse disponível no mercado.

Characterization of a thermostable endoglucanase produced by Isoptericola variabilis sp. IDAH9

Abstract This study aimed to isolate and evaluate the cellulase activity of cellulolytic bacteria in hot springs of Dehloran, Ilam province, Iran. Water and sludge samples were collected from the hot springs and the bacterial enrichment was performed in a medium containing rice barn and carboxymethyl cellulose (CMC). The cultures were incubated at 50 °C in aerobic conditions. The bacteria were isolated on CMC agar (1%) medium. Cellulase assay of the isolates was measured by the evaluation of endoglucanase enzyme activity, which is also called as carboxymethyl cellulase (CMCase). The isolated thermotolerant bacteria were then identified and optimized for the production of CMCase. Moreover, stabilizing elements of the enzyme were identified with in silico approach. The chosen isolate was identified as Isoptericola variabilis sp. IDAH9. The identified strain produced the most thermostable CMCase at a concentration of 5.6 g/L of ammonium sulfate, 9 g/L CMCase or 12 g/L rice bran, 0/6% Tween-80, and 0.2% sucrose. The produced enzyme showed 80% of the residual activity after 1 h of incubation at 65 °C. In silico data indicated that the remaining residual activity was due to the redundant stabilizing elements in the protein structure. Consequently, I. variabilis can be isolated from the extreme environment and has a thermostable endoglucanase which may be used for various applications after studying them.

Cumplimiento de normas microbiológicas en productos alimenticios comercializados en la red de mercados de alimentos del estado Nueva Esparta, Venezuela (período 2006-2014) / Compliance of microbiological norms in food products commercialized in the markets of Nueva Esparta state, Venezuela during the years 2006 to 2014

El suministro de suficientes alimentos es prioritario para garantizar la seguridad alimentaria de una población. También es importante corroborar que sean de calidad e inocuos, para que no causen daño al consumirlos cuando se preparen de acuerdo al uso previsto. Esta investigación verifica si 101 lotes (370 unidades de muestra) de alimentos envasados (harina de maíz, leche en polvo, pasta alimenticia, mortadela, salchicha cocida, carne congelada, pollo congelado, leche UHT, atún enlatado y carne de almuerzo) comercializados en el Estado Nueva Esparta durante los años 2006 a 2014, cumplían requisitos microbiológicos indicados por normas venezolanas. Las muestras fueron captadas por Inspectores de Salud Pública (MPPS). Para los análisis se aplicaron procedimientos de normas COVENIN y FONDONORMA. Cumplieron los requisitos considerados todas las muestras de pasta alimenticia, mortadela, pollo congelado, atún en conserva y carne de almuerzo. Sin embargo, dos lotes de leche UHT y otros dos de carne congelada presentaron recuentos de aerobios mesófilos superiores a las estipulaciones en alguna de las unidades analizadas. Por otra parte, tres de los nueve lotes de salchichas cocidas incumplieron alguno de los requisitos con carácter de recomendación, igualmente 5 de los 16 lotes de harina de maíz (recuentos de mohos) y 10 de los 17 de leche en polvo (recuentos de esporas termófilas). Se concluye que estos incumplimientos pudieran estar ocasionados por fallas de control durante la cadena de producción, re-envasado, almacenamiento o comercialización bien sea de materias primas o de productos terminados.

Enough food supply is a priority to guarantee the food security of a country´s residents. It is also important to supervise that they are harmless for human consumption. This study verifies if 370 packed foods (corn flour, powdered milk, spaghetti, bologna, frozen meat and chicken, pork sausage, UHT milk, canned tuna and luncheon meat), that belonged to 101 production lots commercialized during the years 2006 to 2014 in Nueva Esparta state (Venezuela), fulfill microbiological specifications indicated by Venezuelan norms. Samples were picked up by public health inspectors. For analysis the COVENIN and FONDONORMA procedures were used. All the spaghetti, bologna, frozen chicken, canned tuna and luncheon meat samples complied with the norms. Nevertheless, two UHT milk´s production lots and other two of frozen meat showed total aerobic plate counts higher than the recommended limits. By the other hand, 9 pork sausage´s production lots failed to fulfill a few norms, just as 5 of 16 corn flour lots (molds counts), and 10 of 17 powdered milk production lots (thermophiles spore counts). In conclusion, the nonfulfillment of norms detected, particularly in corn flour and powdered milk samples, are caused by not performing proper controls during the production chain and commercialization of raw materials or finished products.

Nanoactivator mediated modifications in thermostable amylase from Bacillus licheniformis.

Gram-positive rod-shaped thermophilic bacteria were isolated using samples collected from terrestrial natural thermal spring located at Unkeshwar (Longitude 78.22 degree East to 78.34 degree East, Latitude 19 degree 34' North to 19 degree 40' North), District Nanded, Maharashtra State, India. The isolates were then cultivated using selective media and identified using culture-dependent techniques. One prominent isolate (UN1) exhibited high temperature stability and remarkable amylase production and was identified as Bacillus licheniformis. Amylase production was carried out in starch media and the enzyme was partially purified and characterized for optimization of pH and temperature. Amylolytic activity of the enzyme was determined. Nanoactivator-mediated modifications were carried out to enhance amylolytic activity of the partially purified amylase. Three-fold increase in catalytic efficiency of amylase was obtained after modification.

Bioprospecting thermophiles for cellulase production: a review

Most of the potential bioprospecting is currently related to the study of the extremophiles and their potential use in industrial processes. Recently microbial cellulases find applications in various industries and constitute a major group of industrial enzymes. Considerable amount of work has been done on microbial cellulases, especially with resurgence of interest in biomass ethanol production employing cellulases and use of cellulases in textile and paper industry. Most efficient method of lignocellulosic biomass hydrolysis is through enzymatic saccharification using cellulases. Significant information has also been gained about the physiology of thermophilic cellulases producers and process development for enzyme production and biomass saccharification. The review discusses the current knowledge on cellulase producing thermophilic microorganisms, their physiological adaptations and control of cellulase gene expression. It discusses the industrial applications of thermophilic cellulases, their cost of production and challenges in cellulase research especially in the area of improving process economics of enzyme production.

Optimization of fermentation conditions for cellulases production by Bacillus licheniformis MVS1 and Bacillus sp. MVS3 isolated from Indian hot spring

The aim of this work was to study the effect of some nutritional and environmental factors on the production of cellulases, in particular endoglucanase (CMCase) and exoglucanases (FPase) from Bacillus licheniformis MVS1 and Bacillus sp. MVS3 isolated from an Indian hot spring. The characterization study indicated that the optimum pH and temperature value was 6.5 to 7.0 and 50-55°C, respectively. Maximum cellulases production by both the isolates was detected after 60 h incubation period using wheat and rice straw. The combination of inorganic and organic nitrogen source was suitable for cellulases production. Overall, FPase production was much higher than CMCase production by both of the strains. Between the two thermophiles, the cellulolytic activity was more in B.licheniformis MVS1 than Bacillus sp. MVS3 in varying environmental and nutritional conditions.

Protein thermostability in Archaea and Eubacteria

In order to survive at high temperatures, thermophilic prokaryotes (Archaea and Eubacteria) adopt different strategies. Among several important contributing factors for stability of proteins are CG-rich codons, the ratio of charged amino acids compared to uncharged amino acids, ionic interactions, amino acid preferences and their distribution, post-translational modifications, and solute accumulation. However, these factors may differ from taxon to taxon, both within and between species depending upon the composition of proteins found in these organisms. This is exemplified in the case of differences in strategies adopted by soluble proteins and membrane proteins. Therefore, it appears that no single factor or combination of factors together can be universally attributed to the provision of thermal stability in proteins.

Comparison of simple sequence repeats in 19 Archaea

All organisms that have been studied until now have been found to have differential distribution of simple sequence repeats (SSRs), with more SSRs in intergenic than in coding sequences. SSR distribution was investigated in Archaea genomes where complete chromosome sequences of 19 Archaea were analyzed with the program SPUTNIK to find di- to penta-nucleotide repeats. The number of repeats was determined for the complete chromosome sequences and for the coding and non-coding sequences. Different from what has been found for other groups of organisms, there is an abundance of SSRs in coding regions of the genome of some Archaea. Dinucleotide repeats were rare and CG repeats were found in only two Archaea. In general, trinucleotide repeats are the most abundant SSR motifs; however, pentanucleotide repeats are abundant in some Archaea. Some of the tetranucleotide and pentanucleotide repeat motifs are organism specific. In general, repeats are short and CG-rich repeats are present in Archaea having a CG-rich genome. Among the 19 Archaea, SSR density was not correlated with genome size or with optimum growth temperature. Pentanucleotide density had an inverse correlation with the CG content of the genome.