Bioethanol production from urban cellulosic waste employing Alcaligenes faecalis HI-1 isolated from gut of termite Heterotermes indicola

This study assessed the potential of termite gut inhabiting bacteria towards bioconversion of cellulosic waste into biofuel. Total seven bacterial isolates from the gut of Heterotermes indicola were isolated. Among all the isolates, HI-1 produced the largest zone upon primary screening. Untreated paper had more cellulose content (73.03%) than acid (0.5%) treated paper that was used as a lignocellulosic substrate for saccharification. Among all the isolates tested, glucose yield (1.08mg/mL) was high for HI-1 isolate. Several factors were considered for optimizing augmented glucose yield (8.57mg/mL) and growth (8.07×108cfu/mL), such as temperature 37°C, pH 4.5, 5% (w/v) substrate concentration, 6 % bacterial inoculum size, agitation 150 rpm with PEG 0.25 % and Ca2+ ions 0.002 g/L. Overall 8-fold increase in glucose yield was achieved. Enzyme activity of HI-1 showed higher endoglucanase 0.29 ± 0.01 (U/mL/min) and exoglucanase 0.15±0.01 (U/mL/min) activity under optimum conditions, mentioned above. temperature 37°C, pH 4.5, substrate concentration 5%, inoculum size 6%, surfactants PEG 0.01%, ions Ca2+(0.002g/L) and agitation (120 rpm). Simultaneous saccharification and fermentation (SSF) of hydrolyzed office paper yielded 5.43mg/mL bioethanol. According to 16S rRNA sequence homology, the bacterial isolate H1 was identified as Alcaligenes faecalis. Bioethanol production from office paper untreated waste proved an effective strategy. Bacteria having natural tendency towards cellulosic waste consumption are promising for bioconversion of cellulosic waste to valuable products.

Screening of cellulose degradation bacteria from Min pigs and optimization of its cellulase production

BACKGROUND: Cellulose as a potential feed resource hinders its utilization because of its complex structure, and cellulase is the key to its biological effective utilization. Animal endogenous probiotics are more susceptible to colonization in the intestinal tract, and their digestive enzymes are more conducive to the digestion and absorption of feed in young animals. Min pigs are potential sources of cellulase probiotics because of the high proportion of dietary fiber in their feed. In this study, the cellulolytic bacteria in the feces of Min pigs were isolated and screened. The characteristics of enzymes and cellulase production were studied, which provided a theoretical basis for the rational utilization of cellulase and high-fiber food in animal production. RESULTS: In our study, 10 strains of cellulase producing strains were isolated from Min pig manure, among which the M2 strain had the best enzyme producing ability and was identified as Bacillus velezensis. The optimum production conditions of cellulase from strain M2 were: 2% inoculum, the temperature of 35°C, the pH of 5.0, and the liquid loading volume of 50 mL. The optimum temperature, pH and time for the reaction of cellulase produced by strain M2 were 55°C, 4.5 and 5 min, respectively. CONCLUSIONS: Min pigs can be used as a source of cellulase producing strains. The M2 strain isolated from feces was identified as Bacillus velezensis. The cellulase from M2 strain had a good activity and the potential to be used as feed additive for piglets.

Evidencia molecular de la ocurrencia de bacterias celulolíticas del género Cohnella en especies neotropicales de Nasutitermitinae colectadas en el NEA / Molecular evidence that cellulolytic bacterial genus Cohnella is widespread among Neotropical Nasutitermitinae from NE Argentina

Cohnella is a highly cellulolytic bacterial genus, which can be found in a variety of habitats. The aim of this study was to assess its presence in the digestive tract of termite species collected in North-eastern Argentina: Nasutitermes aquilinus, N. corniger and Cortaritermes fulviceps. Gut homogenates were incubated with cellulosic substrate for bacterial growth. Bacterial 16S rDNA was partially amplified using new primers for Cohnella spp. and cloned. Sequences obtained showed highest similarity (97.2-99.9%) with those of Cohnella spp. previously reported from diverse environments. Phylogenetic analysis tended to group the clones according to their host species and sampling sites. These results indicate the association of Cohnella-related intestinal symbionts with three common Neotropical termites. Their potential industrial application encourages further research.

Cohnella es un género de bacterias celulolíticas que puede ser encontrado en una variedad de hábitats. El propósito de este estudio fue registrar su presencia en el tracto digestivo de termitas (Nasutitermes aquilinus, N. corniger y Cortaritermes fulviceps) colectadas en el noreste argentino (NEA). Se incubaron homogenados de intestinos en sustrato celulósico para multiplicar las bacterias. Utilizando nuevos cebadores para Cohnella spp., se amplificó una porción del ADN ribosomal 16S bacteriano, el cual fue posteriormente clonado. Las secuencias obtenidas mostraron su mayor porcentaje de similitud (97,2-99,9%) con Cohnella spp., previamente reportadas en diversos ambientes. El análisis filogenético tendió a agrupar a los clones de acuerdo a la especie hospedante y al sitio de muestreo. Estos resultados indican que especies de termitas frecuentes en el NEA albergan simbiontes intestinales relacionados con el género Cohnella. Las potenciales aplicaciones industriales de estos microorganismos animan a profundizar los estudios.

Measurement of Cellulolytic Potential of Cellulase Producing Bacteria

The bioconversion of cellulose and hemicellulose to soluble sugars is important for global stabilization and for a sustainable human society. Here, hundreds of cellulolytic bacteria were found in soil, compost and animal waste slurry of our environment. Bacillus spp. are aerobic cellulolytic bacteria. Here, two Bacillus strains 2414, 2579 (T) and their mixed culture utilized for measuring the cellulolytic potential. The capability of cellulolytic potential was analyzed by enriching the basal salt media with Whatman no.1 filter paper as a substrate for cellulose degradation. Here, Cellulose-degrading potential of Bacillus strains was measured by measuring the diameter of a clear zone around the colony and its hydrolytic value on cellulose Congo-Red agar media. The extracellular cellulase activities ranged from 0.08233 to 0.44 IU/mL for FPase and 0.243 to 0.595 IU/mL for endoglucanase assay. The maximum activities range of β-glucosidase or cellobiase activity was 0.6 to1.5 1U/ml. The maximum xylanase activities value Bacillus cellulolysticus 2579 (T), Bacillus subtilis 2414 and their mixed culture were 12.0,11.5 and 12.5 unit/mL, respectively. All the enzymes were stable at an optimum pH range value of 3.0-7.0 and temperature range of 30˚C-50˚C. The maximum filter paper degradation percentage was estimated to be 71.76% by mixed culture after 48hrs of incubation period, it was observed that the maximum filter paper degradation was done by mixed culture than Bacillus strains. Biodiesel production was estimated by following the EN-14103 method and ester content was calculated on the basis of response factor with a minimum set value of ester content will be 96.5%.

Characterization of Some Efficient Cellulase Producing Bacteria Isolated from Pulp and Paper Mill Effluent Contaminated Soil

ABSTRACT The wide variety of bacteria in the environment permits screening for more efficient cellulases to help overcome current challenges in biofuels production. This study focuses on the isolation of efficient cellulase producing bacteria found in pulp and paper mill effluent contaminated soil which can be considered for use in large scale biorefining. Four different bacterial strains were isolated and screened for cellulase production by using CMC agar medium. All isolates showed cellulase activity these strains were further characterized by morphological, physiological, biochemical and 16S rRNA gene analyses. These isolates were identified as two Bacillus subtilis sub sps, Bacillus mojavensis and Bacillus cereus.

Screening and identification of indigenous cellulolytic bacteria from Indonesian coffee pulp and investigation of its caffeine tolerance ability

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. .

Optimization of Endoglucanase Production from a Novel Bacterial Isolate, Arthrobacter sp. HPG166 and Characterization of Its Properties

ABSTRACTIn this study, a potential novel cellulolytic bacteriumArthrobacter sp. HPG166 was isolated from the hindgut of root-feeding larvaeHolotrichia parallela. Optimization of fermentation factors for endoglucanase production byArthrobacter sp. HPG166 was carried out via response surface methodology. Sodium carboxymethylcellulose 1.19% (w/v) and beef extract 0.35% (w/v) were the ideal combination of carbon and nitrogen sources for enzyme production; the optimum temperature and pH for cellulase production were 34°C and pH 8.0 respectively. Under the optimized fermentation conditions, the maximum endoglucanase activity of 1.411 U mL-1 was obtained. The crude endoglucanase was thermotolerant as it retained 50.31% of its activity after incubation at 70°C for an hour. Metal profile of the enzyme indicated that Mg2+ and Na+ were strong stimulators while Mn2+ and Co+ drastically inhibited its activity. Due to its particular characteristics, this enzyme could have potential for industrial applications.

Screening and identification of cellulase producing bacteria isolated from oil palm meal.

Oil palm (Elaeis guineensis) meal, a by-product of palm oil, is rich in fiber and contains lignocelluloses, which inhibits the absorption of the nutrients has been widely used for animal feed. The improvement of the nutrient absorption is required treating with cellulase enzyme. This study was aimed to isolate, screen and characterize the cellulase producing bacteria. Ten strains of cellulolytic bacteria were isolated from 7 oil palm meal samples collected in Phetchaburi, Prachuap Khiri Khan and Pattani provinces, Thailand. They exhibited the ability to degrade carboxymethyl-cellulose (CMC) based on the decolorization of CMC-basal agar medium using Congo red as a color indicator. They showed the cellulase hydrolysis capacity ranged from 1.56 to 4.14. All isolates were Gram positive rod-shaped bacteria and belonged to Bacillus (8 isolates), Paenibacillus (1 isolate) and Lysinibacillus (1 isolate) based on the phenotypic characteristics and 16S rRNA gene sequence analysis. Their cellulase activity ranged from 0.039±0.002 to 0.233±0.005 IU/ml when they were cultivated in broth.

Variación espacial y estacional de grupos funcionales de bacterias cultivables del suelo de un bosque tropical seco en México / Spatial and seasonal variation of soil culturable-bacterial functional groups in a Mexican tropical dry forest

Microbial biomass and activity in soils are frequently studied in tropical dry forests, but scarce information is available about the relationships between functional bacterial groups and soil fertility, where relief interacts with rainfall seasonality. The culturable-bacterial groups and nutrients were studied during two consecutive years in soils from two topographic areas of different relief (hilltop vs hillslope) in a tropical dry forest from Chamela Jalisco, Mexico. We expected that seasonal and spatial variation in soil resources availability affects the abundance of functional culturable-bacterial groups. To evaluate this, fifteen soil cores (1kg), 0-5cm depth, were taken in the dry, early rainy and rainy seasons, from each of the ten replicate plots in hilltop and hillslope areas located in three microbasins. We found that hilltop soils were more organic and had higher concentration of labile C and total nutrient forms than hillslope soils, for which these soils had higher counts of colony-forming units (CFU) of total heterotrophic and P solubilizing bacteria. In both hilltop and hillslope soils, C and nutrient concentrations, as well as the counts of CFU of heterotrophic and P solubilizing bacteria generally decreased from the dry to the rainy season during the two study years. In contrast, the counts of CFU nitrifying and cellulolytic bacteria were higher at the hillslope than at the hilltop soils. The seasonal pattern of both groups was opposite to that of heterotrophic bacteria, presumably associated with a decrease in soil labile C and organic matter quality. In conclusion, our study suggests that available C appears to be the main factor that controls the structure of soil bacterial groups and soil fertility, where relief, rainfall seasonality and intraand inter-annual variations are critical factors that interactively modify bacterial dynamics related to soil C availability in the tropical dry forest.

Los bosques tropicales secos tienen una amplia heterogeneidad ambiental y por lo tanto se podría esperar una variación temporal y espacial en la abundancia y tipo de grupos bacterianos activos. Se evaluó, durante dos años consecutivos, el efecto de la estacionalidad de la lluvia sobre algunos grupos bacterianos cultivables y nutrimentos del suelo en dos posiciones topográficas (crestas vs laderas) en el bosque tropical seco, Chamela Jalisco, México. La hipótesis fue que la variación temporal y espacial de la disponibilidad de recursos afectaría la abundancia de los grupos bacterianos funcionales (heterótrofas totales, celulolíticas, solubilizadores de fosfatos y nitrificantes) del suelo. En las crestas, el suelo fue más orgánico y con mayor concentración de nutrimentos totales y C orgánico lábil que en la ladera, registrando más bacterias heterótrofas y solubilizadoras de fosfato. En ambas posiciones topográficas la concentración de C y nutrimentos, así como el número de bacterias heterótrofas y solubilizadoras de P, decrecieron de la estación seca a la lluviosa en ambos años. En contraste, las bacterias nitrificantes fueron mayores en el suelo de la ladera, y al igual que las celulolíticas, tuvieron un patrón estacional opuesto a las bacterias heterótrofas, asociado a la disminución del C lábil y de la calidad de la materia orgánica. En conclusión, se sugiere que el relieve, la estacionalidad y la variación inter-anual de la lluvia regulan interactivamente la relación entre el C disponible y la estructura de las comunidades bacterianas del suelo en el bosque tropical seco de Chamela.