Biopolymer Producers Research Articles

Biosurfactant and biopolymer producing microorganisms from West Kazakhstan oilfield

Microbiological enhanced oil recovery (MEOR) uses indigenous or exogenous microorganisms and nutrients to enhance oil production through synthesis of metabolites reducing oil viscosity and surface tension. In order to find bacteria suitable for MEOR, we studied 26 isolates from wells in the Akingen oilfield in West Kazakhstan. Six of them were selected for further analysis based on their ability to reduce surface tension to less than 40 mN/m, with the A9 isolate exhibiting tension reduction values of 32.76 ± 0.3 mN/m. Based on the morphological features, biochemical activities, and the 16S rRNA gene, the isolates were classified to the Bacillus subtilis group. In the phylogenetic analysis the isolates grouped into two main clusters. Genes encoding the surfactin synthetase subunits were found in A2, A8, A9, A12, PW2, only the PW2 strain had lchAA encoding lichenysin, while sacB encoding levan was noted in A2, A8, A9, and A12. The expression of srfAB, srfAC, and sacB tested with qPCR varied among strains. Nevertheless, whereas temperature moderately affects the expression level, with the highest level recorded at 40 °C, salinity significantly impacts the expression of the genes encoding biosurfactants. B. subtilis strains isolated in the study, especially A9, are promising for microbial-enhanced oil recovery.

Rational engineering of natural polyhydroxyalkanoates producing microorganisms for improved synthesis and recovery.

Microbial production of biopolymers derived from renewable substrates and waste streams reduces our heavy reliance on petrochemical plastics. One of the most important biodegradable polymers is the family of polyhydroxyalkanoates (PHAs), naturally occurring intracellular polyoxoesters produced for decades by bacterial fermentation of sugars and fatty acids at the industrial scale. Despite the advances, PHA production still suffers from heavy costs associated with carbon substrates and downstream processing to recover the intracellular product, thus restricting market positioning. In recent years, model-aided metabolic engineering and novel synthetic biology approaches have spurred our understanding of carbon flux partitioning through competing pathways and cellular resource allocation during PHA synthesis, enabling the rational design of superior biopolymer producers and programmable cellular lytic systems. This review describes these attempts to rationally engineering the cellular operation of several microbes to elevate PHA production on specific substrates and waste products. We also delve into genome reduction, morphology, and redox cofactor engineering to boost PHA biosynthesis. Besides, we critically evaluate engineered bacterial strains in various fermentation modes in terms of PHA productivity and the period required for product recovery.

Particle-dependent reproduction and exogenic biopolymer secretion of protozoa co-cultured rotifers

The rotifer-specific exogenic biopolymer, named Rotimer and its related molecular processes are affected by physical and chemical factors (e.g., temperature, pH or metal ions); however, the study of biological influences (e.g., the presence protozoa) concerning the particle-dependent reproduction (egg laying) and ‘biopolymer producing capacity’ (BPC) of rotifers is the objective of the present work. Non-planktonic rotifer species (Philodina acuticornis, Adineta vaga, Euchlanis dilatata, and Lecane bulla) were studied in paired micrometazoa-protozoa co-cultures involving Paramecium, Diplonema, and Amoeba. These protozoa can be beneficial food sources, enhancing reproduction, or even toxic factors for the above-mentioned animals, but can also function as particle-like mechanical stimulators. Furthermore, current studies reveal that bdelloids, similarly to monogonants, produce filamentous exudate; moreover, the body of bdelloids is covered by their exudate, unlike that of monogonants, especially in the case of A. vaga. A mathematical formula was developed as an improved version of a previously published viability marker to characterize the BPC and the relative amount of produced exudate in different conditions.Rotifer species secreting biopolymers appear to be a general trait indicating a common evolutionary background (e.g., calcium- and particle dependency) of such molecules; therefore, the BPC becomes an experiential sublethal influencing marker to these micrometazoans.

Characterization and Application of Biopolymer Producing Bacteria for Enhanced Oil Recovery

The objective of this research is to isolate and identify hydrocarbon-degrading bacteria for biopolymer synthesis and application in the augmentation of Nigerian heavy crude oil recovery. MEOR refers to the process of injecting either indigenous or non-indigenous microbes into hydrocarbon reserves. Injecting microorganisms with nutritional broth facilitate the formation of essential metabolites such as biosurfactants, biopolymers, and gases, resulting in decreased interfacial tension, viscosity modification, and mobility control. It is environmentally friendly, less expensive to implement, and requires minimal or no changes to the existing infrastructure. A soil sample from a hydrocarbon-contaminated site in Ogoniland was collected and sent to a laboratory for physicochemical and microbiological investigation. Bacillus sp, Pseudomonas sp, and Klebsiella sp were biochemically identified after screening three isolates for biopolymer production using Sudan black solution. To assess the ideal growth and biopolymer synthesis capability under reservoir conditions, a variety of pH, temperature, salinity, carbon, and nitrogen nutrition sources were applied to selected microorganisms. Peptone is the optimal nitrogen source for Bacillus sp, glucose is the optimal carbon source for Bacillus sp, and glycerol is the optimal carbon source for Pseudomonas sp and Klebsiella sp, as indicated by the results. In addition, the following are the ideal parameter ranges for the three microorganisms: pH 7–8, a temperature range between 25 and 350 degrees Celsius, and a salinity range between 0.5 and 5% are all desirable conditions for a body of water. After inoculation with microorganisms and the optimum nutrient source, an additional recovery range of 18.33% to 29.09% of the pore capacity was achieved. The post-recovery analysis uncovered a remarkable transformation of heavy crude to light hydrocarbon components by an average of 20.33 percent with glucose and 97.27 percent with peptone.

A Novel Insight Into the Fabrication of Polyhydroxyalkanoates from Actinobacteria Streptomyces toxytricini D2: Screening, Optimization, and Biopolymer Characterization

The aim of this research was to identify a biopolymer producing potential actinobacteria candidate from polluted soil. The Streptomyces toxytricini D2 was enumerated as potential biopolymer producer, which was isolated and characterized using 16S rRNA sequencing. The S. toxytricini D2 produced polymeric granules were categorized through FTIR, 1H NMR, and 13C NMR analyses, which confirmed that the granules were Polyhydroxyalkanoates (PHAs). The S. toxytricini D2 has the competence to produce 86.56% of PHAs (23.64 g L−1 of PHAs from 27.31 g L−1 of biomass) under optimized growth conditions: 8% of tapioca molasses, 4% of (NH4)2SO4, 8% of inoculum, pH 6.5, 30 °C and 72 h of incubation. These findings concluded that S. toxytricini D2 could be used as an efficient candidate for the mass production of PHAs polymer under optimized conditions, with a low-cost carbon source and in a short time of production period.

Investigations on Presence of Biopolymer Producing Microorganism in Marine Soils & Enhanced Potential of Marine Soil by Using Isolated Microorganism

Gujarat has a very extended coastal belt, and due to type, the properties of available soil in the coastal regions vary from place to place. These soil properties are not suitable for infrastructure development. Many techniques were already developed for the improvement of marine soil strength. Some of them are very costly; some method is not suitable due to high water table in the region. Some have adverse effects on aquatic life. This study has an approach to give sustainable, eco-friendly, and economical techniques to increase the unconfined compressive strength of marine soil of the different regions. The entire colonies available in soil are studied by series dilution and spread plate technique. Microorganisms produce exopolysaccharides (EPS) in excess carbohydrates, which provides by the screening method in nutrient agar broth (N. agar). Microbial Biopolymer such as exopolysaccharides can act as an eco-friendly binder of soil. EPS-producing organisms work as an environmentally sustainable method to improve soil strength. More exopolysaccharides-producing and fastest-growing microorganisms were selected by EPS extraction from all microorganisms found in a survey. The result was also compared with the unconfined compressive strength achieved by bio cement and a mixture of biopolymer and biocement. The biopolymer shows an increase in result (1.625– 1.891) times from 14 days to 28 days. Biocement showed an increase in the result, which ranges from (1.763–1.955), and the mixture of both shows a tremendous increment of (1.635-1.885).

Engineering Native and Synthetic Pathways in Pseudomonas putida for the Production of Tailored Polyhydroxyalkanoates.

Growing environmental concern sparks renewed interest in the sustainable production of (bio)materials that can replace oil-derived goods. Polyhydroxyalkanoates (PHAs) are isotactic polymers that play a critical role in the central metabolism of producer bacteria, as they act as dynamic reservoirs of carbon and reducing equivalents. PHAs continue to attract industrial attention as a starting point toward renewable, biodegradable, biocompatible, and versatile thermoplastic and elastomeric materials. Pseudomonas species have been known for long as efficient biopolymer producers, especially for medium-chain-length PHAs. The surge of synthetic biology and metabolic engineering approaches in recent years offers the possibility of exploiting the untapped potential of Pseudomonas cell factories for the production of tailored PHAs. In this article, an overview of the metabolic and regulatory circuits that rule PHA accumulation in Pseudomonas putida is provided, and approaches leading to the biosynthesis of novel polymers (e.g., PHAs including nonbiological chemical elements in their structures) are discussed. The potential of novel PHAs to disrupt existing and future market segments is closer to realization than ever before. The review is concluded by pinpointing challenges that currently hinder the wide adoption of bio-based PHAs, and strategies toward programmable polymer biosynthesis from alternative substrates in engineered P. putida strains are proposed.

Medium optimisation as a first step towards the feasible production of biopolymers with Botryococcus braunii

Current interest in the production of commercial biopolymers which are derived from renewable resources arises from the necessity to move from a fossil-based to a more sustainable economy. Microalgae are considered potential biopolymer producers although their use at an industrial scale is not feasible yet. In this sense, medium optimisation and operational conditions can be considered the first steps leading to growth and product productivity enhancement which are a prerequisite to boost the microalgae industry. This manuscript describes medium optimisation for two promising strains of the green alga Botryococcus braunii, B. braunii CCALA-778 (race A) and B. braunii AC761 (race B), which are natural producers of (exo)polysaccharides and hydrocarbons of high interest in the biopolymers industry. Medium optimisation was based on a three-step research process: (i) a literature survey to identify macro- and micronutrients that could be limiting Botryococcus growth, (ii) a 3-level factorial design experiment in microwell plates to evaluate modified media accordingly and (iii) validation of previous results in batch cultivation in Roux flasks. The results obtained show the significant impact of culture media optimisation in the growth dynamics and valuable compound accumulation of B. braunii. Attention should be given to each particular Botryococcus race and media should be defined accordingly. But overall, the new optimised media resulted in higher productivities which may contribute to reach sustainability of Botryococcus cultivation.

Exopolysaccharide production by an indigenous isolate Pseudomonas stutzeri XP1 and its application potential in enhanced oil recovery

In this study, a rapid and efficient method for screening biopolymer producers was established using 96-well plates. An indigenous biopolymer producer Pseudomonas stutzeri XP1 was isolated from Xinjiang oil reservoirs, China. Strain XP1 can grow and produce 16 g/l biopolymer using corn starch and nitrate. Produced biopolymer increased culture viscosity up to 2384 mPa s. Biopolymer showed rheological properties and pseudo-plastic behavior. The viscosity of 8 g/l biopolymer solution kept higher than 25 mPa s at 20–50 °C and pH values (5–9) and increased to 7600 mPa s with NaCl concentrations increasing to 2%. Gel permeation chromatography data showed that the biopolymer average molecular mass was 1.65 × 106 Da. Gas chromatography revealed that the monosaccharide composition in biopolymer was glucose. Core flooding experiments revealed that extra 13.56% of oil was recovered by in situ biopolymer production of strain XP1. Properties of strain XP1 and the biopolymer produced make them promising for enhanced oil recovery.

Screening for Biopolymer Producing Symbiotic Nitrogen Fixers from Western Ghats

Screening for Biopolymer Producing Symbiotic Nitrogen Fixers from Western Ghats

Green Plastics: Analysis of a Firm’s Sustainability Orientation for Innovation

This study aims to evaluate the orientation towards sustainability for a company’s innovation project, grounded in three aspects: the importance of the triple bottom line dimensions; the stakeholders’ engagement; and the nature of competencies necessary to this innovation. In order to do achieve our objective, we have gathered data from a case study of the green plastic project in Braskem, the biggest chemical company in Brazil and in America, and one of the biggest biopolymer producers worldwide. Thus, the study addresses the following propositions: P 1 : Sustainability-oriented innovation must have also environmental and social criteria, besides economic criteria; P 2 : Sustainability-oriented innovation has multiple stakeholders-related criteria selection, besides own company shareholders; and P 3 : Sustainability-oriented innovation projects demand major presence of competencies if compared to traditional ones. The main results show the prevalence of environmental indicators over others, the very importance of the value chain and knowledge as a basis for sustainability-oriented innovation.

The Screening of Biopolymer Bacteria in Porous MediaThe Screening of Biopolymer Bacteria in Porous Media

MEOR has advantages of less polluting environment and low cost, which can be extended to the volume of the biopolymer produced by metabolism, and it is one of the main mechanisms of microbial enhanced oil recovery. The fermentation, the study of biopolymers produced growth and metabolism of bacteria rules; after using the orthogonal experimental method and optimized the optimum culture conditions, through the indoor driving oil experimental evaluation of biological polymer flooding effect. The optimal bio polymer producing strain DJ was screened out. The strain had the ability to produce polymer and the product quantity was high. The effect of the biopolymer flooding was good. DJ strain optimum culture time for 72 hours, the optimal fermentation culture conditions: fermentation temperature 35 degrees Celsius; shaking speed r/min; 10 mL of inoculum; fermentation culture medium formula: glucose 40 g/L, 20 g/L of corn steep liquor, corn starch 2 G/L, NaNO3 3 g/L, KH2PO4 0.5 g/L, Na2HPO4·12H2O 1 g/L, MgSO4·7H2O 0.5 g/L, CaCl2 0.05 g/L, pH 7.2.

Characterization of biopolymer producing Streptomyces parvulus, optimization of process parameters and mass production using less expensive substrates

PHB is attracting much attention as substitute for non-degradable petro-chemically derived plastics because of their similar material properties to conventional plastics and complete biodegradability under natural environment upon disposal. Out of ten actinomycetes isolates obtained from different soil samples, the PHB accumulating isolate was identified by Rapid screening method and based on the morphological, physiological, biochemical and molecular studies, the isolate was identified as Streptomyces parvulus RL01 (GenBank Accession no: JX457345. The influence of incubation time, carbon source and nitrogen source on the PHB accumulation was studied. PHB accumulation was maximum in 48 h of incubated in a medium with 1.5% lactose as carbon source and 1% casein as nitrogen source yielded maximum PHB accumulation of 1.7g/L and 2.9g/L respectively. For the production of PHB various inexpensive substrates such as Casava podwer, Coconut oil cake Ground nut oil, Jack fruit seed powder, Potato starch, Rice bran and Wheat bran were used and it was found that PHB production was maximum in whey (2.8 g/L) and minimum in other substrates (1 g/L, 0.1 g/L, 0.2 g/L, 1 g/L, 1 g/L, 0.3 g/L and 0.3 g/L).

Screening of Biopolymer Producing Bacteria Isolated from Some Brassica Plants

Biopolymer producing bacteria were isolated from some Brassica plants such as cabbage, cauliflower and lettuce. Total counts of these samples were enumerated and predominant mucoid colonies were selected for further studies. These isolated strains were identified as Panteo agglomerans, Bacillus subtilis, Enterobacter sp. and Pseudomonas sp. The biopolymer producing ability of these isolates was studied using yeast malt (YM) broth. The fermentation studies were carried out in Erlenmeyer flasks containing 100ml YM broth. After 72h cell dry weight, viscosity and remaining reducing sugar content of the media were estimated. Using ice cold ethanol the biopolymer produced was precipitated, dried and weighed. Among the isolates Pseudomonas sp. produced a maximum of 3.17g/l of biopolymer.

Microbial diversity and functionally distinct groups in produced water from the Daqing Oilfield, China

The microbial community structure and functionally distinct groups in three kinds of produced water samples from the shallow, mesothermic and low-salinity Daqing oil reservoir were systematically evaluated using both culture-dependent and culture-independent methods. Sequence analysis of the 16S rRNA genes indicated that the bacterial library was dominated by Acinetobacter and Arcobacter and the archaeal community was dominated by Methanosaeta and Methanolinea. Two isolated methanogens were closely related with Methanothermobacter thermautotrophicus and Methanoculleus receptaculi. The fermentative bacteria were identified as Pseudomonas, Haloanaerobium, Alcalibacter, Arcobacter, and Pannonibacter. The predominant nitrate-reducing bacteria fell within the genus Pseudomonas. The dominant members of the cultured hydrocarbon-oxidizing bacteria were phylogenetically associated with Micrococcus, Pseudomonas, and Bacillus. Enrichments of biosurfactants and biopolymer producing groups mainly yielded Pseudomonas, Bacillus, and Acenitobacter-related members. The functional groups related to polymer degradation were also affiliated with Pseudomonas and Bacillus. Results from this study provide the fresh insight into the diversity of microbial communities in Daqing petroleum reservoirs. The vast pool of functional strains retrieved in this study was presumed to include the promising strains that could be applied in microbial-enhanced oil recovery in future.

Biochemical diversity of the bacterial strains and their biopolymer producing capabilities in wastewater sludge

The biochemical characterization of 13 extracellular polymeric substances (EPS) producing bacterial strains were carried out by BIOLOG. The bacterial strains were cultured in sterilized sludge for EPS production. Flocculation and dewatering capabilities of produced EPS (broth, crude slime and capsular) were examined using kaolin suspension combined with calcium (150mg of Ca2+/L of kaolin suspension). BIOLOG revealed that there were 9 Bacillus, 2 Serratia and 2 Yersinia species. Most of these bacterial strains had the capability to utilize wide spectrum of carbon and nitrogen sources. EPS concentration of more than 1g/L was produced by most of the bacterial strains. Concentration of EPS produced by different Bacillus strains was higher than that of Serratia and Yersinia. Broth EPS revealed flocculation activity more than 75% for Bacillus sp.7, Bacillus sp.4 and Bacillus sp.6, respectively. Flocculation activity higher than 75% was attained using very low concentrations of broth EPS (1.12–2.70mg EPS/g SS).