Cryptic diversity of cellulose-degrading gut bacteria in industrialized humans.

Humans, like all mammals, depend on the gut microbiome for digestion of cellulose, the main component of plant fiber. However, evidence for cellulose fermentation in the human gut is scarce. We have identified ruminococcal species in the gut microbiota of human populations that assemble functional multienzymatic cellulosome structures capable of degrading plant cell wall polysaccharides. One of these species, which is strongly associated with humans, likely originated in the ruminant gut and was subsequently transferred to the human gut, potentially during domestication where it underwent diversification and diet-related adaptation through the acquisition of genes from other gut microbes. Collectively, these species are abundant and widespread among ancient humans, hunter-gatherers, and rural populations but are rare in populations from industrialized societies thus indicating potential disappearance in response to the westernized lifestyle.

Exploring increased hydraulic retention time as a cost-efficient way of valorizing residual biogas potential.

Effective substrate utilization with low residual methane yield in the digestate is crucial for the economy and sustainability of biogas plants. The composition and residual methane potential of 29 digestate samples from plants operating at hydraulic retention times of 13-130 days were determined to evaluate the economic viability of extended digestion. Considerable contents of fermentable fractions, such as cellulose (8-23%), hemicellulose (1-18%), and protein (13-22%), were present in the digestate dry matter. The ultimate residual methane yields varied between 55 and 236 ml/g of volatile solids and correlated negatively with the logarithm of the hydraulic retention time (r = -0.64, p < 0.05). Economic analysis showed that extending the retention time in 20 days would be viable for 18 systems if methane were sold for 1.00 €/m3, with gains up to 40 €/year/m3 of newly installed reactor capacity. The results show the importance of operating at sufficient hydraulic retention time.

Assessment of biodegradability of cellulose and poly(butylene succinate)-based bioplastics under mesophilic and thermophilic anaerobic digestion with a view towards biorecycling.

Despite the increasing interest in bioplastics, there are still contradictory results on their actual biodegradability, which cause difficulties in choosing and developing appropriate sustainable treatment methods. Two biofoils (based on poly(butylene succinate) (PBS37) and cellulose (Cel37)) were anaerobically degraded during 100-day mesophilic (37 °C) and thermophilic (55 °C) tests (PBS55, Cel55). To overcome low degradation rates in mesophilic conditions, alkaline pre-treatment was also used (Pre-PBS37, Pre-Cel37). For comprehensive understanding of biodegradability, not only methane production (MP), but also the structure (topography, microscopic analysis), tensile properties, and FTIR spectra of the materials undergoing anaerobic degradation (AD) analysed. PBS37 and Pre-PBS37 were visible in 100-day degradation, and the cumulative MP reached 25.5 and 29.3 L/kg VS, respectively (4.3-4.9% of theoretical MP (TMP)). The biofoils started to show damage, losing their mechanical properties over 35 days. In contrast, PBS55 was visible for 14 days (cracks and fissures appeared), cumulative MP was 180.2 L/kg VS (30.2% of the TMP). Pieces of Cel were visible only during 2 days of degradation, and the MP was 311.4-315.0 L/kg VS (77.3-78.2% of the TMP) at 37 °C and 319.5 L/kg VS (79.3% of the TMP) at 55 °C. The FTIR spectra of Cel and PBS did not show shifts and formation of peaks. These findings showed differences in terms of the actual biodegradability of the bioplastics and provided a deeper understanding of their behaviour in AD, thus indicating limitations of AD as the final treatment of some materials, and also may support the establishment of guidelines for bioplastic management.

High aspect ratio nanomaterial-induced macrophage polarization is mediated by changes in miRNA levels.

Introduction: Inhalation of nanomaterials may induce inflammation in the lung which if left unresolved can manifest in pulmonary fibrosis. In these processes, alveolar macrophages have an essential role and timely modulation of the macrophage phenotype is imperative in the onset and resolution of inflammatory responses. This study aimed to investigate, the immunomodulating properties of two industrially relevant high aspect ratio nanomaterials, namely nanocellulose and multiwalled carbon nanotubes (MWCNT), in an alveolar macrophage model. Methods: MH-S alveolar macrophages were exposed at air-liquid interface to cellulose nanocrystals (CNC), cellulose nanofibers (CNF) and two MWCNT (NM-400 and NM-401). Following exposure, changes in macrophage polarization markers and secretion of inflammatory cytokines were analyzed. Furthermore, the potential contribution of epigenetic regulation in nanomaterial-induced macrophage polarization was investigated by assessing changes in epigenetic regulatory enzymes, miRNAs, and rRNA modifications. Results: Our data illustrate that the investigated nanomaterials trigger phenotypic changes in alveolar macrophages, where CNF exposure leads to enhanced M1 phenotype and MWCNT promotes M2 phenotype. Furthermore, MWCNT exposure induced more prominent epigenetic regulatory events with changes in the expression of histone modification and DNA methylation enzymes as well as in miRNA transcript levels. MWCNT-enhanced changes in the macrophage phenotype were correlated with prominent downregulation of the histone methyltransferases Kmt2a and Smyd5 and histone deacetylases Hdac4, Hdac9 and Sirt1 indicating that both histone methylation and acetylation events may be critical in the Th2 responses to MWCNT. Furthermore, MWCNT as well as CNF exposure led to altered miRNA levels, where miR-155-5p, miR-16-1-3p, miR-25-3p, and miR-27a-5p were significantly regulated by both materials. PANTHER pathway analysis of the identified miRNA targets showed that both materials affected growth factor (PDGF, EGF and FGF), Ras/MAPKs, CCKR, GnRH-R, integrin, and endothelin signaling pathways. These pathways are important in inflammation or in the activation, polarization, migration, and regulation of phagocytic capacity of macrophages. In addition, pathways involved in interleukin, WNT and TGFB signaling were highly enriched following MWCNT exposure. Conclusion: Together, these data support the importance of macrophage phenotypic changes in the onset and resolution of inflammation and identify epigenetic patterns in macrophages which may be critical in nanomaterial-induced inflammation and fibrosis.

Utilizing rice straw and sugarcane bagasse as low-cost feedstocks towards sustainable production of succinic acid.

Succinic acid (SA) has been produced from rice straw (RS) and sugarcane bagasse (SB) as low-cost feedstocks in this study through sequential peracetic acid (PA) and alkaline peroxide (AP) pretreatment assisted by ultrasound and pre-hydrolysis followed by simultaneous saccharification and fermentation (PSSF). The effect of yeast extract (YE) concentration, inoculum concentration, and biomass type on SA production was investigated. The results showed that SA production from RS and SB was significantly affected by the YE concentration. Final concentration and yield of SA produced were significantly increased along with the increasing of YE concentration. Moreover, inoculum concentration significantly affected the SA production from SB. Higher inoculum concentration led to higher SA production. On the other hand, SA production from RS was not significantly affected by the inoculum concentration. Using RS as the feedstock, the highest SA production was achieved on the medium containing 15 g/L YE with 5 % v/v inoculum, obtaining SA concentration and yield of 3.64 ± 0.1 g/L and 0.18 ± 0.05 g/g biomass, respectively. Meanwhile, the highest SA production from SB was acquired on the medium containing 10 g/L YE with 7.5 % v/v inoculum, resulting SA concentration and yield of 5.1 ± 0.1 g/L and 0.25 ± 0.05 g/g biomass, respectively. This study suggested that RS and SB are potential to be used as low-cost feedstocks for sustainable and environmentally friendly SA production through ultrasonic-assisted PA and AP pretreatment and PSSF.

Fabrication of biodegradable chicken feathers into ecofriendly-functionalized biomaterials: characterization and bio-assessment study.

This study aims to investigate novel applications for chicken feather waste hydrolysate through a green, sustainable process. Accordingly, an enzymatically degraded chicken feather (EDCFs) product was used as a dual carbon and nitrogen source in the production medium of bacterial cellulose (BC). The yield maximization was attained through applying experimental designs where the optimal level of each significant variable was recorded and the yield rose 2 times. The produced BC was successfully characterized by FT-IR, XRD and SEM. On the other hand, sludge from EDCFs was used as a paper coating agent. The mechanical features of the coated papers were evaluated by bulk densities, maximum load, breaking length, tensile index, Young's modulus, work to break and coating layer. The results showed a decrease in tensile index and an increase in elongation at break. These indicate more flexibility of the coated paper. The coated paper exhibits higher resistance to water vapor permeability and remarkable oil resistance compared to the uncoated one. Furthermore, the effectiveness of sludge residue in removing heavy metals was evaluated, and the sorption capacities were ordered as Cu ++ > Fe ++ > Cr ++ > Co ++ with high affinity (3.29 mg/g) toward Cu ++ and low (0.42 mg/g) towards Co ++ in the tested metal solution.

Plasma Promotes Fungal Cellulase Production by Regulating the Levels of Intracellular NO and Ca2.

For the industrial-scale production of useful enzymes by microorganisms, technological development is required for overcoming a technical bottleneck represented by poor efficiency in the induction of enzyme gene expression and secretion. In this study, we evaluated the potential of a non-thermal atmospheric pressure plasma jet to improve the production efficiency of cellulolytic enzymes in Neurospora crassa, a filamentous fungus. The total activity of cellulolytic enzymes and protein concentration were significantly increased (1.1~1.2 times) in media containing Avicel 24-72 h after 2 and 5 min of plasma treatment. The mRNA levels of four cellulolytic enzymes in fungal hyphae grown in media with Avicel were significantly increased (1.3~17 times) 2-4 h after a 5 min of plasma treatment. The levels of intracellular NO and Ca2+ were increased in plasma-treated fungal hyphae grown in Avicel media after 48 h, and the removal of intracellular NO decreased the activity of cellulolytic enzymes in media and the level of vesicles in fungal hyphae. Our data suggest that plasma treatment can promote the transcription and secretion of cellulolytic enzymes into the culture media in the presence of Avicel (induction condition) by enhancing the intracellular level of NO and Ca2+.

A critical review for advances on industrialization of immobilized cell Bioreactors: Economic evaluation on cellulose hydrolysis for PHB production.

Advances such as cell-on-cell immobilization, multi-stage fixed bed tower (MFBT) bioreactor, promotional effect on fermentation, extremely low temperature fermentation, freeze dried immobilized cells in two-layer fermentation, non-engineered cell factories, and those of recent papers are demonstrated. Studies for possible industrialization of ICB, considering production capacity, low temperatures fermentations, added value products and bulk chemical production are studied. Immobilized cell bioreactors (ICB) using cellulose nano-biotechnology and engineered cells are reported. The development of a novel ICB with recent advances on high added value products and conceptual research areas for industrialization of ICB is proposed. The isolation of engineered flocculant cells leads to a single tank ICB. The concept of cell factories without GMO is a new research area. The conceptual development of multi-stage fixed bed tower membrane (MFBTM) ICB is discussed. Finally, feasible process design and technoeconomic analysis of cellulose hydrolysis using ICB are studied for polyhydroxybutyrate (PHB) production.

In vitro assessment of two novel Cellulases from Trabulsiella odontotermitis for agricultural waste utilization.

BACKGROUND: The production of agricultural wastes still growing as a consequence of the population growing. However, the majority of these residues are under-utilized due their chemical composition, which is mainly composed by cellulose. Actually, the search of cellulases with high efficiency to degrade this carbohydrate remains as the challenge. In the present experiment, two genes encoding an endoglucanase (EC 3.2.1.4) and ß-glucosidase (EC 3.2.1.21) were overexpressed in Escherichia coli and their recombinant enzymes (egl-FZYE and cel-FZYE, respectively) characterized. Those genes were found in Trabulsiella odontermitis which was isolated from the gut of termite Heterotermes sp. Additionally, the capability to release sugars from agricultural wastes was evaluated in both enzymes, alone and in combination. RESULTS: The results have shown that optimal pH was 6.0 and 6.5, reaching an activity of 1051.65 ± 47.78 and 607.80 ± 10.19 U/mg at 39 °C, for egl-FZYE and cel-FZYE, respectively. The Km and Vmax for egl-FZYE using CMC as substrate were 11.25 mg/mL and 3921.57 U/mg, respectively, whereas using Avicel were 15.39 mg/mL and 2314.81 U/mg, respectively. The Km and Vmax for cel-FZYE using Avicel as substrate were 11.49 mg/mL and 2105.26 U/mg, respectively, whereas using CMC the enzyme did not had activity. Both enzymes had effect on agricultural wastes, and their effect was improved when they were combined reaching an activity of 955.1 ± 116.1, 4016.8 ± 332 and 1124.2 ± 241 U/mg on corn stover, sorghum stover and pine sawdust, respectively. CONCLUSIONS: Both enzymes were capable of degrading agricultural wastes, and their effectiveness was improved up to 60% of glucose released when combined. In summary, the results of the study demonstrate that the recombinant enzymes exhibit characteristics that indicate their value as potential feed additives and that the enzymes could be used to enhance the degradation of cellulose in the poor-quality forage generally used in ruminant feedstuffs.

Competitive Exclusion and Metabolic Dependency among Microorganisms Structure the Cellulose Economy of an Agricultural Soil.

Microorganisms that degrade cellulose utilize extracellular reactions that yield free by-products which can promote interactions with noncellulolytic organisms. We hypothesized that these interactions determine the ecological and physiological traits governing the fate of cellulosic carbon (C) in soil. We performed comparative genomics with genome bins from a shotgun metagenomic-stable isotope probing experiment to characterize the attributes of cellulolytic and noncellulolytic taxa accessing 13C from cellulose. We hypothesized that cellulolytic taxa would exhibit competitive traits that limit access, while noncellulolytic taxa would display greater metabolic dependency, such as signatures of adaptive gene loss. We tested our hypotheses by evaluating genomic traits indicative of competitive exclusion or metabolic dependency, such as antibiotic production, growth rate, surface attachment, biomass degrading potential, and auxotrophy. The most 13C-enriched taxa were cellulolytic Cellvibrio (Gammaproteobacteria) and Chaetomium (Ascomycota), which exhibited a strategy of self-sufficiency (prototrophy), rapid growth, and competitive exclusion via antibiotic production. Auxotrophy was more prevalent in cellulolytic Actinobacteria than in cellulolytic Proteobacteria, demonstrating differences in dependency among cellulose degraders. Noncellulolytic taxa that accessed 13C from cellulose (Planctomycetales, Verrucomicrobia, and Vampirovibrionales) were also more dependent, as indicated by patterns of auxotrophy and 13C labeling (i.e., partial labeling or labeling at later stages). Major 13C-labeled cellulolytic microbes (e.g., Sorangium, Actinomycetales, Rhizobiales, and Caulobacteraceae) possessed adaptations for surface colonization (e.g., gliding motility, hyphae, attachment structures) signifying the importance of surface ecology in decomposing particulate organic matter. Our results demonstrated that access to cellulosic C was accompanied by ecological trade-offs characterized by differing degrees of metabolic dependency and competitive exclusion.IMPORTANCE Our study reveals the ecogenomic traits of microorganisms participating in the cellulose economy of soil. We identified three major categories of participants in this economy: (i) independent primary degraders, (ii) interdependent primary degraders, and (iii) secondary consumers (mutualists, opportunists, and parasites). Trade-offs between independent primary degraders, whose adaptations favor antagonism and competitive exclusion, and interdependent and secondary degraders, whose adaptations favor complex interspecies interactions, are expected to affect the fate of microbially processed carbon in soil. Our findings provide useful insights into the ecological relationships that govern one of the planet's most abundant resources of organic carbon. Furthermore, we demonstrate a novel gradient-resolved approach for stable isotope probing, which provides a cultivation-independent, genome-centric perspective into soil microbial processes.

From cheese whey permeate to Sakacin-A/bacterial cellulose nanocrystal conjugates for antimicrobial food packaging applications: a circular economy case study.

Applying a circular economy approach, this research explores the use of cheese whey permeate (CWP), by-product of whey ultrafiltration, as cheap substrate for the production of bacterial cellulose (BC) and Sakacin-A, to be used in an antimicrobial packaging material. BC from the acetic acid bacterium Komagataeibacter xylinus was boosted up to 6.77 g/L by supplementing CWP with ß-galactosidase. BC was then reduced to nanocrystals (BCNCs, 70% conversion yield), which were then conjugated with Sakacin-A, an anti-Listeria bacteriocin produced by Lactobacillus sakei in a CWP based broth. Active conjugates (75 Activity Units (AU)/mg), an innovative solution for bacteriocin delivery, were then included in a coating mixture applied onto paper sheets at 25 AU/cm2. The obtained antimicrobial food package was found effective in reducing Listeria population in storage trials carried out on a fresh Italian soft cheese (named "stracchino") intentionally inoculated with Listeria. Production costs of the active material have been mainly found to be associated (90%) to the purification steps. Setting a maximum prudential 50% cost reduction during process up-scaling, conjugates coating formulation would cost around 0.89 €/A4 sheet. Results represent a practical example of a circular economy production procedure by using a food industry by-product to produce antimicrobials for food preservation.

Bacterial cellulose: From production optimization to new applications.

Bacterial cellulose (BC) is a biopolymer of great significance to the medical, pharmaceutical, and food industries. However, a high concentration of carbon sources (mainly glucose) and other culture media components is usually required to promote a significant yield of BC, which increases the bioprocess cost. Thus, optimization strategies (conventional or statistical) have become relevant for the cost-effective production of bacterial cellulose. Additionally, this biopolymer may present new properties through modifications with exogenous compounds. The present review, explores and discusses recent studies (last five years) that report the optimization of BC production and its yield as well as in situ and ex situ modifications, resulting in improved mechanical, antioxidant, and antimicrobial properties of BC for new applications.

Performance targets defined by retro-techno-economic analysis for the use of soybean protein as saccharification additive in an integrated biorefinery.

The use of additives in the enzymatic saccharification of lignocellulosic biomass can have positive effects, decreasing the unproductive adsorption of cellulases on lignin and reducing the loss of enzyme activity. Soybean protein stands out as a potential lignin-blocking additive, but the economic impact of its use has not previously been investigated. Here, a systematic evaluation was performed of the process conditions, together with a techno-economic analysis, for the use of soybean protein in the saccharification of hydrothermally pretreated sugarcane bagasse in the context of an integrated 1G-2G ethanol biorefinery. Statistical experimental design methodology was firstly applied as a tool to select the process variable solids loading at 15% (w/w) and soybean protein concentration at 12% (w/w), followed by determination of enzyme dosage at 10 FPU/g and hydrolysis time of 24 h. The saccharification of sugarcane bagasse under these conditions enabled an increase of 26% in the amount of glucose released, compared to the control without additive. The retro-techno-economic analysis (RTEA) technique showed that to make the biorefinery economically feasible, some performance targets should be reached experimentally such as increasing biomass conversion to ideally 80% and reducing enzyme loading to 5.6 FPU/g in the presence of low-cost soybean protein.

Taste compound - Nanocellulose interaction assessment by fluorescence indicator displacement assay.

Interactions between taste compounds and nanofibrillar cellulose were studied. For this, a new fluorescent indicator displacement method was developed. Two fluorescent indicators, namely, Calcofluor white and Congo red, were chosen because of their specific binding to cellulose and intrinsic fluorescence. Seven taste compounds with different structures were successfully measured together with nanofibrillar cellulose (NFC) and ranked according to their binding constants. The most pronounced interactions were found between quinine and NFC (1.4 × 104 M-1), whereas sucrose, aspartame and glutamic acid did not bind at all. Naringin showed moderate binding while stevioside and caffeine exhibited low binding. The comparison with microcrystalline cellulose indicates that the larger surface area of nanofibrillated cellulose enables stronger binding between the binder and macromolecules. The developed method can be further utilized to study interactions of different compound classes with nanocellulose materials in food, pharmaceutical and dye applications, using a conventional plate reader in a high-throughput manner.

In vitro toxicity assessment of hydrogel patches obtained by cation-induced cross-linking of rod-like cellulose nanocrystals.

With the purpose of designing active patches for photodynamic therapy of melanoma, transparent and soft hydrogel membranes (HMs) have been fabricated by cation-induced gelation of rod-like cellulose nanocrystals (CNCs) bearing negatively charged carboxylic groups. Na+ , Ca2+ , Mg2+ have been used as cross-linkers of cellulose nanocrystal (CNC). The biosafety of this material and of its precursors has been evaluated in vitro in cell cultures. Morphological changes, cell organelles integrity, and cell survival with the tetrazolium salt reduction (MTT) assay were utilized as tests of cytotoxicity. Preliminary investigation was performed by addition of the hydrogel components to the cell culture medium and by incubations of the CNC-HM in direct and indirect contact with a confluent monolayer of A375 melanoma cells. Direct contact assays suffered from interference of physical stress. Careful evaluation of cytotoxicity was obtained considering the overall picture provided by microscopy and biochemical tests performed with the CNC-HM in indirect contact with two melanoma cell lines (A375, M14) and human fibroblasts. CNCs have been demonstrated to be a safe precursor material and CNC-HMs have a good biocompatibility provided that the excess of cations, in particular of Ca2+ is removed. These results indicate that CNC and can be safely used to fabricate biomedical devices such as transparent hydrogel patches, although attention must be paid to the fabrication procedure.

Designing a cellulolytic enzyme cocktail for the efficient and economical conversion of lignocellulosic biomass to biofuels.

Concerns about dwindling fossil fuels and their unfavorable environmental impacts shifted the global focus towards the development of biofuels from lignocellulosic feedstocks. The structure of this biomass is very complex due to which variety of enzymes (cellulolytic, hemicellulolytic, auxiliary/AA9) and proteins (e.g. swollenin) required for efficient deconstruction. Major impediments in large-scale commercial production of cellulosic ethanol are the cost of cellulases and inability of any single microorganism to produce all cellulolytic components in sufficient titers. In the recent past, various methods for reducing the enzyme cost during cellulosic ethanol production have been attempted. These include designing optimal synergistic enzyme blends/cocktail, having certain ratios of enzymes from different microbial sources, for efficient hydrolysis of pretreated biomass. However, the mechanisms underlying the development, strategies for production and evaluation of optimal cellulolytic cocktails still remain unclear. This article aims to explore the technical and economic benefits of using cellulolytic enzyme cocktail, basic enzymatic and non-enzymatic components required for its development and various strategies employed for efficient cellulolytic cocktail preparation. Consideration was also given to the ways of evaluation of commercially available and in-house developed cocktails. Discussion about commercially available cellulolytic cocktails, current challenges and possible avenues in the development of cellulolytic cocktails included.

Biofuel production from straw hydrolysates: current achievements and perspectives.

Straw is an agricultural residue of the production of e.g. cereals, rapeseed or sunflowers. It includes dried stalks, leaves, and empty ears and corncobs, which are separated from the grains during harvest. Straw is a promising lignocellulosic feedstock with a beneficial greenhouse gas balance for the production of biofuels and chemicals. Like all lignocellulosic materials, straw is recalcitrant and requires thermochemical and enzymatic pretreatment to enable access to the three major biopolymers of straw-the polysaccharides cellulose and hemicellulose and the polyaromatic compound lignin. Straw is used for commercial ethanol and biogas production. Considerable research has also been conducted to produce biobutanol, biodiesel and biochemicals from this raw material, but more research is required to establish them on a commercial scale. The major hindrance for launching industrial biofuel and chemicals' production from straw is the high cost necessitated by pretreatment of the material. Improvements of microbial strains, production and extraction technologies, as well as co-production of high-value compounds represent ways of establishing straw as feedstock for the production of biofuels, chemicals and food.

Adding value to lignocellulosic wastes via their use for endoxylanase production by Aspergillus fungi.

Agroforestry industries in the world generate lignocellulosic wastes that can be a huge problem of pollution, or the wastes can be used for different biotechonological applications such as substrates for microorganism growth and enzyme production. Fungi such as Aspergillus niger can grow in almost every substrate and produce hydrolytic enzymes such as endoxylanases, giving added value to agroforestry wastes generated by industries in the northeast of Argentina. In this context, the aim of this work was to use agroforestry wastes as substrates for the production of endoxylanases by Aspergillus niger and to optimize nitrogen sources and physical variables for the highest endoxylanase activity. A. niger LBM 055 and A. niger LBM 134 produced high endoxylanase levels when they were grown with sugarcane and cassava bagasses as carbon sources. A. niger LBM 134 reached the highest endoxylanase activity when nitrogen sources and physical variables were optimized. The fungus exhibited up to 110 U mL-1 of endoxylanase activity when it was grown with sugarcane bagasse and more than 160 U mL-1 with cassava bagasse. Therefore, endoxylanase production was optimized using agricultural bagasses and cost 20 times less than enzyme production using synthetic xylan.

Assessment of white rot fungus mediated hardwood degradation by FTIR spectroscopy and multivariate analysis.

Evaluating the biomass degradation using fast, validate and sensitive techniques for exploratory purposes of biofuel production has been developed since last decade. Thus, we assessed the degradation of two Indian hardwoods using FTIR and chemometric approaches. Two white rot fungi, namely Pseudolagarobasidium acaciicola AGST3 and Tricholoma giganteum AGDR1, were selected among twenty-one fungal isolates for higher hardwood degradation. In the screening, P. acaciicola AGST3 and T. giganteum AGDR1 depicted the dry woody mass loss of 20.51% and 22.38%, respectively. Cellulose crystallinity of P. acaciicola AGST3 treated hardwoods was 4-fold lower than untreated hardwoods, showing the higher cellulose degradation efficiency. P. acaciicola AGST3 treated samples exhibited maximum deviation of guaiacyl units of lignin, cellulose and hemicelluloses. T. giganteum AGDR1 treated hardwoods showed maximum deviation of guaiacyl- and syringyl- units of lignin and hemicelluloses. Multivariate approach revealed the degradation patterns and preferences are varied based on the fungi and hardwood. The approach used in the present study can certainly distinguish the variations among the different biomass samples that having similar composition. Additionally, higher lignin degradability of these fungi can be used in biomass pretreatment, which significantly utilized to produce second-generation biofuels.

Monascus orange and red pigments production by Monascus purpureus ATCC16436 through co-solid state fermentation of corn cob and glycerol: An eco-friendly environmental low cost approach.

The present study underlines a statistically optimized, low cost, effective approach for efficient co-valorization of two non-efficiently utilized, highly accumulated, raw agro-industrial wastes: corn cob and glycerol for co-production of natural biopigments: monascus orange and red pigments by the aid of Monascus purpureus strain ATCC 16436. A three step sequential, statistical modeling approach: one variable at a time (OVAT), Plackett-Burman design (PBD), and central composite design (CCD) was employed to optimize the production of monascus pigments using co-solid state fermentation of the two raw agro-industrial wastes. Corn cob among other carbon sources (e.g., rice grains, sugarcane bagasse, and potato peel) was the most appropriate substrate triggering co-production of orange and red monascus pigments; deduced from OVAT. Glycerol and inoculum size proved to impose significant consequences (P<0.05) on the production of monascus pigments as inferred from PBD. The optimal levels of inoculum size (12 x 1011 spores/mL) and glycerol (2.17 M) did achieve a maximal color value of 133.77 and 108.02 color value units/mL of orange and red pigments, respectively at 30 oC after 10 days; concluded from CCD with an agitation speed of 150 rpm. Present data would underpin the large scale production of monascus pigments using the present approach for efficient exploitation of such biopigments in food, pharmaceutical and textile industries.