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OBJECTIVEPosterior fixation with interbody cage placement can be accomplished via numerous techniques. In an attempt to expedite recovery by limiting muscle dissection, midline lumbar interbody fusion (MIDLIF) has been described. More recently, the authors have developed a robot-assisted MIDLIF (RA-MIDLIF) technique. The purpose of this study was to compare the index episode-of-care (iEOC) parameters between patients undergoing traditional open transforaminal lumbar interbody fusion (tTLIF), MIDLIF, and RA-MIDLIF.METHODSA retrospective review of a prospective, multisurgeon surgical database was performed. Consecutive patients undergoing 1- or 2-level tTLIF, MIDLIF, or RA-MIDLIF for degenerative lumbar conditions were identified. Patients in each cohort were propensity matched based on age, sex, smoking status, BMI, diagnosis, American Society of Anesthesiologists (ASA) class, and number of levels fused. Index EOC parameters such as length of stay (LOS), estimated blood loss (EBL), operating room (OR) time, and actual, direct hospital costs for the index surgical visit were analyzed.RESULTSOf 281 and 249 patients undergoing tTLIF and MIDLIF, respectively, 52 cases in each cohort were successfully propensity matched to the authors’ first 55 RA-MIDLIF cases. Consistent with propensity matching, there was no significant difference in age, sex, BMI, diagnosis, ASA class, or levels fused. Spondylolisthesis was the most common indication for surgery in all cohorts. The mean total iEOC was similar across all cohorts. Patients undergoing RA-MIDLIF had a shorter average LOS (1.53 days) than those undergoing either MIDLIF (2.71 days) or tTLIF (3.58 days). Both MIDLIF and RA-MIDLIF were associated with lower EBL and less OR time compared with tTLIF.CONCLUSIONSDespite concerns for additional cost and time while introducing navigation or robotic technology, a propensity-matched comparison of the authors’ first 52 RA-MIDLIF surgeries with tTLIF and MIDLIF showed promising results for reducing OR time, EBL, and LOS without increasing cost.

Introduction: To date, over 1,000 lichen secondary metabolites have been identified. Despite their promising cytotoxic properties, the number of literature reports on anticancer evaluation of lichenochemicals is limited. As cancer prevalence among the human population increases, there is growing interest in lichens as a natural source of secondary metabolites for anti-cancer drug discovery and development.Areas covered: The lack of significant progress in lichen anticancer research is due to the low levels of cytotoxic compounds contained in lichens, the technical difficulties associated with their isolation and characterization, and the insufficient understanding of their mechanism of action on different cancer cell lines. In this review, the authors discuss these challenges and provide systematically organized information on the limitations and advantages of commonly used and newly developed methods for lichen exploration and screening of lichen secondary metabolites for their anticancer potential.Expert opinion: Recent research activities have demonstrated that lichen secondary metabolites possess chemotherapeutic properties. A systematic and multidisciplinary approach is required to advance lichen research and improve our understanding of the mechanisms responsible for the potent cytotoxic properties of lichenochemicals. More efforts need to focus on screening and discovery of new lichen-derived compounds with unique anticancer properties.

Biodiesel is a promising renewable energy source that can be used together with other biofuels to help meet the growing energy needs of the rapidly increasing global population in an environmentally friendly way. In search for new and more efficient biodiesel production methods, this work reports on the synthesis and use of a novel biocatalyst that can function in a broader range of pH and temperature conditions, while producing high biodiesel yields from vegetable oils. Biodiesel was synthesized by transesterification of non-edible Eruca sativa oil using a lipase from Aspergillus niger that was immobilized on cerium oxide bismuth oxide nanoparticles. The synthesized nanoparticles were first grafted with polydopamine which facilitated the subsequent anchoring of the enzyme on the nanoparticle support. The enzyme activity, pH and temperature stability, and reusability of the immobilized lipase were superior to those of the free enzyme. Following response surface methodology optimization, the highest biodiesel yield of 90.6% was attained using 5 wt% biocatalyst, methanol to oil ratio of 6:1, reaction temperature of 40 °C, pH of 7, and reaction time of 60 h. The produced biodiesel was characterized by Fourier transform infrared spectroscopy and its fatty acid methyl ester composition was determined by gas chromatography-mass spectrometry. Erucic acid methyl ester was identified as the major component in biodiesel, with 47.7 wt% of the total fatty acid methyl esters content. The novel nanobiocatalyst (Bi2O3·CeO2@PDA@A.niger.Lipase) has the potential to produce high biodiesel yields from a variety of vegetable oils.

Biodiesel is a biodegradable, renewable, and carbon-neutral alternative to petroleum diesel that can contribute to the global effort of minimizing the use of fossil fuels and meeting the ever-growing energy demands and stringent environmental constraints. The aim of this work was to (1) review the recent progress in feedstock development, including first, second, third, and fourth-generation feedstocks for biodiesel production; (2) discuss recent progress in lipase research and development as one of the key factors for establishing a cost-competitive biodiesel process in terms of enzyme sources, properties, immobilization, and transesterification efficiency; and (3) provide an update of the current challenges and opportunities for biodiesel commercialization from techno-economic and social perspectives. Related biodiesel producers, markets, challenges, and opportunities for biodiesel commercialization, including environmental considerations, are critically discussed.

Crude tall oil (CTO) is the third largest by-product at kraft pulp and paper mills. Due the large presence of value-added fatty and resin acids, CTO has a huge valorization potential as a biobased, readily available, non-food, and low-cost biorefinery feedstock. The objective of this work was to present a method for the isolation of high-value linoleic acid (LA), an omega (&omega, )-6 essential fatty acid, from CTO using a combination of pretreatment, fractionation, and purification techniques. Following the distillation of CTO to separate the tall oil fatty acids (TOFAs) from CTO, LA was isolated and purified from TOFAs by urea complexation (UC) and low-temperature crystallization (LTC) in the temperature range between &minus, 7 and &minus, 15 &deg, C. The crystallization yield of LA from CTO in that range was 7.8 w/w at 95.2% purity, with 3.8% w/w of &omega, 6 &gamma, linolenic acid (GLA) and 1.0% w/w of &omega, 3 &alpha, linolenic (ALA) present as contaminants. This is the first report on the isolation of LA from CTO. The approach presented here can be applied to recover other valuable fatty acids. Furthermore, once the targeted fatty acid(s) are isolated, the rest of the TOFAs can be utilized for the production of biodiesel, biobased surfactants, or other valuable bioproducts.

The green bacterial cellulose (BC)-based hydrogel materials have successfully prepared by modification and crosslink BC. BC was derived from acetic acid bacteria isolated and selected from ripe fruits. The production of BC was performed by fermentation in various media. It was found that using liquid potato medium represented the highest thickness of BC film (0.80 cm) with 2 wt% solid content covered the media. To reduce the crystallization of BC, carboxyl group was introduced onto BC chains using a carboxymethylation reaction giving carboxymethyl BC (CMBC) and subsequently crosslinked with divinyl sulfone (DVS). The extent of crosslinking influenced on the swelling properties of the hydrogels. Using large DVS amounts (>30 wt%-of CMBC), dense macromolecular network with less capacity spaces in the hydrogel was formed. The maximum water retention value of green hydrogels containing ~3.0 mmol carboxyl groups/g CMBC reached 27 (g/g).

We have developed a new, aqueous-based process for production of superabsorbent materials that is catalyst-free and eco-friendly as the superabsorbent was derived from two completely biodegradable ...

Addition of surfactants to enzymatic hydrolysis has been reported to enhance the hydrolytic potential of enzymes in the bioconversion of lignocellulosic biomass to fermentable sugars. The objective of this investigation was to evaluate the effects of four non-ionic surfactants (PEG4000, PEG8000, TitronX-100, and Tween80) on the efficiency of enzymatic hydrolysis of steam-pretreated poplar using a commercial cellulase preparation (Cellic® CTec2). Statistical discriminant analysis at four variable factors (surfactant type, surfactant concentration, hydrolysis time, and substrate consistency) revealed that enzymatic hydrolysis was significantly enhanced in the presence of PEG4000, with 19.2% increase in glucose yield over control without surfactant, whereas ANOVA test indicated substrate consistency and hydrolysis time as the most significant factors (P

Biodiesel production from crude tall oil (CTO) in presence of a commercial lipase catalyst (Eversa Transform) was optimized using Taguchi method. Process parameters including reaction temperature, molar ratio of CTO to methanol, reaction time, and enzyme dose were examined for their effect on the in-situ esterification of fatty acids (FA) in CTO to fatty acid methyl ester (FAME). Fractional distillation was employed to separate the FAME fraction (biodiesel) from the rest of the CTO components. Using Taguchi (L9) Orthogonal Design, the optimum biodiesel yield was statistically predicted and experimentally verified as 97.02% and 96.57%, respectively. The optimal conversion of CTO to crude biodiesel was obtained at 16 h reaction time, 40 °C reaction temperature, 1:1.5 CTO to methanol molar ratio, and 1.0 wt% enzyme dose. The reaction time and CTO to methanol molar ratio were the two most contributing factors for the optimal conversion of CTO to biodiesel.

Inhibitors generated during biomass pretreatment negatively affect fermentability of biomass hydrolysates and need to be removed prior to fermentation. In this study, four different polymeric resins were evaluated for their abilities to remove acid soluble lignin (ASL) from poplar hydrolysate. The ASL removal capabilities of Amberlite IRA-400 (OH−) and XAD-4 were similar (96.7% and 97.3%, respectively), however 88% of xylo-saccharides (XS) were lost with XAD-4 treatment as compared to 21% with IRA-400 (OH−) treatment. IRA-400 (OH−) was also efficient in adsorption of aromatic-based inhibitors such as benzoic acid, vanillin and 4-hydroxybenzoic acid. The consecutive resin IRA-400 (OH−) → enzyme (HTec2) treatment removed 79.5% of ASL from the hydrolysate at a loss of only 9.5% of xylo-based carbohydrates (XBC). This improved the hydrolysate fermentability to ethanol attaining 41.5 g/L ethanol titer and 89.6% ethanol yield at a sugar utilization efficiency of 95.3% after 72 h of fermentation.

Lichens provide a large array of compounds with the potential for pharmaceutical development. In the present study, extracts from three previously undescribed North American lichen species were examined for antioxidant, antibacterial and anticancer activities.; Results: The results from this study demonstrated the following: (i) Acarospora socialis ethanol extract exhibited significant DPPH antioxidant scavenging activities, which were concentration dependent; (ii) acetone and ethyl acetate extracts of Xanthoparmelia mexicana inhibited Gram-positive bacteria but had no effect on Gram-negative bacteria; X. mexicana acetone extract yielded a minimum inhibitory concentration (MIC) of 20.9 µg mL-1 against Staphylococcus aureus, and 41.9 µg mL-1 against Enterococcus faecalis; (iii) acetone extract of Lobothallia alphoplaca inhibited growth of cultured breast cancer MCF-7 cells with an effective concentration (EC50 ) of 87 µg mL-1 ; the MCF-7 cell cycle appears arrested in the G2 phase, whereas the DNA synthesis cell cycle (S) may be inhibited.; Conclusion: New lichen species that possess strong biological activities have been identified. These lichens comprise secondary metabolites that possess antioxidant, antibacterial and anticancer properties. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

Study Design:Systematic review and case series.Objectives:Any acute injury to the posterior elements of the lumbar spine resulting in listhesis is considered a traumatic spondylolisthesis. This rare injury caused by high-energy trauma is variably described in the literature as fracture-dislocation, where only case reports and series have been published. Our objectives were to propose evidence-based treatment recommendations and a new classification system for this injury.Methods:A systematic review of literature from PubMed, EMBASE, and Cochrane without time frame limitations was performed, which included 77 level IV and V articles and 9 patients as case series in the analysis.Results:A total of 125 cases were reviewed with mean age of 30.5 years. Half of the cases resulted from a vehicular accident. Back pain presented in 82%, while 50% had neurologic deficits. Operative treatment was performed in 93.6% (posterior decompression [PD] = 4%; posterior spinal fusion [PSF] = 43.2%; interbody fusion [IB] = 46.4%) with overall fusion rates of 74%. Binomial regression analysis for achieving solid fusion showed a 28.6× higher odds for IB compared to PSF ( P = .008, r2= 0.633). Subanalysis of cases with disc injuries revealed higher fusion outcomes for IB (87%) compared to PSF (46%; P = .006), while there were no significant differences for patients without disc injury. Pain and neurological symptoms improved significantly on final follow-up ( P < .001). Overall complication rate was 22%.Conclusion:Operative management with reduction, decompression for neurologic deficits, instrumentation, and fusion is recommended for traumatic spondylolisthesis. Interbody fusion is recommended to achieve better fusion outcomes especially with preoperatively identified disc lesions.

Objective: Lichens are emerging as a promising natural source of bioactivities of pharmaceutical interest. The present study aims to contribute to the knowledge of the lichen Umbilicaria muhlenbergii as a potential source of pharmaceutically relevant anticancer and antibiotic lichen chemicals. Methods: The crude acetone extract of U. muhlenbergii exhibited 13.3 μg mL-1 cytotoxic activity (EC50) against breast cancer cells (MCF-7), as compared to a cisplatin positive control with EC50 of 5.8 μg mL-1. The antibiotic activity of the crude extract against a gram-positive Staphylococcus aureus was 22.5 μg mL-1 as MIC. Using silica gel 60 (SG60) column chromatography, the crude extract was then separated into eight fractions, which were further evaluated for their anticancer activities against MCF-7 cells. By means of propidium iodide flow cytometry, two of the eight SG60 fractions were found to cause cell cycle arrest in MCF-7 cells (73.14% of cells) at the G2 phase, which is indicative of apoptosis and inhibition of cellular proliferation. Results: Identification of chemical constituents present in these two SG60 fractions was carried out with Thin-Layer Chromatography (TLC) and a lichen metabolite database (Wintabolites). The two fractions (SG60-5 and SG60-6) were found to contain compounds belonging to the chemical families depsides, depsidones, anthraquinones, and xanthones. Discussion: The SG60-5 and SG60-6 fractions were further fractionated with Sephadex LH-20. Over 15% of the 46 LH-20 fractions obtained from the SG60-5 fraction caused 100% cell death, whereas 32% of the LH-20 fractions derived from SG60 6 fraction reduced cell survival to below 20%. Conclusion: This work extends the evaluation of the cytotoxic and antibiotic activities of lichen secondary metabolites to the species U. muhlenbergii. It presents encouraging results of pharmaceutical interest that set up lichens as an effective source of new bioactive natural products. Further investigations are underway to reveal the full biopharmaceutical potential of U. muhlenbergii.

Nowadays, most of the commonly used superabsorbent polymers (SAPs) are derived from synthetic polymers, particularly acrylic acid and its copolymers made with acrylamide. Here, we describe a novel and environmentally friendly aqueous-based process for fabrication of a new, natural, cellulose-based SAP (hydrogel). In this two-step process, cellulose was first reacted with sodium monochloroacetate (MCA) to obtain carboxymethyl cellulose (CMC) and then cross-linked with epichlorohydrin (ECH). In distilled water (d-water), the water retention value (WRV) of the newly fabricated hydrogels reached 725 g d-water/g gel, which is significantly greater than any other commercially available superabsorbent cellulose-based material (WRV of 10-100 g/g) and comparable to the commercial synthetic (polyacrylate) SAP gels (WRV of up to 1000 g/g). In saline water (s-water; 0.9% NaCl), the maximum WRV attained was 118 g s-water/g gel, which exceeds more than 2-fold the WRV of commercial gels (40-50 g/g). Compositional analysis was carried out to determine the amount of carboxyl groups and average molecular mass, and the parameters for hydrogel preparation were optimized. The natural SAP was characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The hydrogels showed good re-swelling properties losing only 5-10% of their capabilities to reabsorb d-water when reused in four consecutive cycles. Because of their superior swelling properties in physiological saline, the new hydrogels can compete with their synthetic counterparts in applications such as high-value hygiene and biomedical products.

The objective of this work was to examine opportunities for reducing the overall cost of lignocellulose hydrolysis to fermentable sugars. Primary sludge (PS), a negative cost lignocellulosic feedstock, was hydrolyzed sludge using a commercial cellulase preparation (Cellic® CTec2) in presence of non-ionic surfactants. Polyethylene glycol (PEG) 4000 facilitated the highest hydrolysis yield of 74.4% which represented a 2-fold increase over the control without surfactant. Response surface methodological analysis at four variables (hydrolysis time, solids, enzyme, and surfactant loadings) revealed that enzymatic hydrolysis was significantly enhanced by the interactive effect of all factors with solids and enzyme loadings as the most significant parameters (p

A strictly anaerobic, thermophilic bacterium, designated strain YS13, was isolated from a geothermal hot spring. Phylogenetic analysis using the 16S rRNA genes and cpn60 UT genes suggested strain YS13 as a species of Thermoanaerobacter. Using cellobiose or xylose as carbon source, YS13 was able to grow over a wide range of temperatures (45–70 °C), and pHs (pH 5.0–9.0), with optimum growth at 65 °C and pH 7.0. Metabolic profiling on cellobiose, glucose, or xylose in 1191 medium showed that H2, CO2, ethanol, acetate, and lactate were the major metabolites. Lactate was the predominant end product from glucose or cellobiose fermentations, whereas H2and acetate were the dominant end products from xylose fermentation. The metabolic balance shifted away from ethanol to H2, acetate, and lactate when YS13 was grown on cellobiose as temperatures increased from 45 to 70 °C. When YS13 was grown on xylose, a metabolic shift from lactate to H2, CO2, and acetate was observed in cultures as the temperature of incubation increased from 45 to 65 °C, whereas a shift from ethanol and CO2to H2, acetate, and lactate was observed in cultures incubated at 70 °C.

Background: The Romberg test is used to identify balance issues in patients with Cervical Spondylotic Myelopathy (CSM), but has subjective interpretation. The purpose of this study is to evaluate force plate pressure readings during a Romberg test to quantify postural control. Methods: Quantitative Romberg force plate readings with eyes open and closed in patients with CSM were obtained and changes in balance measurements were compared to a normal population (N = 28, mean age 39 ± 7 years). Results: We identified 30 CSM patients with a mean age of 58 ± 10 years. Majority of patients presented with pain (90%) and neurologic symptoms (83%). Cord compression on imaging was identified in 90%. Mean eyes closed Romberg measurements were larger compared to eyes open measurements in CSM patients (p

Supplemental Material, GSJ801882_suppl_mat for Traumatic Lumbar Spondylolisthesis: A Systematic Review and Case Series by Mikhail Lew P. Ver, John R. Dimar, and Leah Y. Carreon in Global Spine Journal

BACKGROUND A thermophilic lipase-producing Geobacillus thermodenitrificans strain AV-5 was isolated from the Mushroom Spring of Yellowstone National Park in WY, USA and studied as a source of lipase for transesterification of vegetable oils to biodiesel. RESULTS A maximum activity of 330 U mL−1 was produced on 2% (v/v) waste cooking oil at 50 °C, pH 8, aeration rate of 1 vvm and agitation speed of 400 rpm. However, the higher lipase productivity (14.04 U mL−1 h−1) was found at a volumetric oxygen transfer coefficient (kLa) value of 18.48 h−1. The partially purified lipase had a molecular weight, temperature and pH optimum of 50 kDa, 65 °C and pH 9, respectively, and was thermo-alkali stable: at 70 °C, it retained 81% activity and 45% stability; at pH 10 it lost only 15% and 2.6% of its maximum activity and stability, respectively. Enzyme kinetic studies with p-nitrophenyl laurate as substrate revealed high substrate specificity (km of 0.440 mmol L−1) and kinetic activity (vmax of 556 nmol mL min−1) of lipase. CONCLUSIONS The kLa was found to be highly dependent on aeration and agitation rates. Following optimization of fermentation medium and parameters, a 7.5-fold increase in lipase production by G. thermodenitrificans was attained. The lipase activity and substrate specificity (as km) are among the highest reported in the literature for bacterial lipases. It was demonstrated that the enzyme can produce biodiesel from waste cooking oil with a conversion yields of 76%. © 2015 Society of Chemical Industry

The efficiency and dynamics of simultaneous kenaf biomass decomposition by basidiomycetous fungi and actinobacteria were investigated. After 8weeks of incubation, up to 34wt.% of the kenaf biomass was degraded, with the combination of fungi and bacteria being the most efficient. Lignin decomposition accounted for ∼20% of the observed biomass reduction, regardless of the culture used. The remaining 80% of biomass degradation was due to carbohydrate based polymers. Major monosaccharides were produced in tangible yields (26-38%) at different times. Glucose, fructose and xylose were then fully consumed by day 25 while some galactose persisted until day 45. Once monosaccharides were depleted, the production of laccase, manganese-dependent peroxidase and lignin peroxidase enzymes, essential for lignin decomposition, was induced. The products of lignin biodecomposition were shown to be water-soluble and characterized by thermal desorption-pyrolysis-gas chromatography.

The primary objective of this work was to investigate the thermal and rheological properties of crude tall oil (CTO), a low-cost by-product from the Kraft pulping process, as a potential feedstock for biodiesel production. Adequate knowledge of CTO properties is a prerequisite for the optimal design of a cost-effective biodiesel process and related processing equipment. The study revealed the correlation between the physicochemical properties, thermal, and rheological behavior of CTO. It was established that the trans/esterification temperature for CTO was greater than the temperature at which viscosity of CTO entered a steady-state. This information is useful in the selection of appropriate agitation conditions for optimal biodiesel production from CTO. The point of interception of storage modulus (G′) and loss modulus (G′′) determined the glass transition temperature (40 °C) of CTO that strongly correlated with its melting point (35.3 °C). The flow pattern of CTO was modeled as a non-Newtonian fluid. Furthermore, due to the high content of fatty acids (FA) in CTO, it is recommended to first reduce the FA level by acid catalyzed methanolysis prior to alkali treatment, or alternatively apply a one-step heterogeneous or enzymatic trans/esterification of CTO for high-yield biodiesel production.

Numerous microbial factors are responsible for perioperative infections and influence the efficacy of antibiotic prophylaxis. These factors include the staphylococcal carrier state, bacterial adherence to a number of host proteins, the production of glycocalyx by sessile bacteria, and shifts in antibiotic resistance. A full understanding of the mechanisms involved will lead to further reductions in the number of postoperative infections. Unfortunately, the microbial factors affecting prophylaxis cannot be evaluated separately under clinical conditions; they are easier to study under circumstances whose bacteriologic features are well defined and in which the presence of foreign materials (e.g., sutures) greatly potentiates pathogenic mechanisms. Such circumstances exist, for example, in infections developing after "clean” surgery and in experimental models. Since even clean wounds are found to be contaminated when sampled carefully, the control of infection is more a quantitative than a qualitative problem. The critical period for the development of infection is short: an antibiotic course not exceeding 24 hours seems effective in preventing infection

Lactic acid is an intermediate-volume specialty chemical for a wide range of food and industrial applications such as pharmaceuticals, cosmetics and chemical syntheses. Although lactic acid production has been well documented, improved production parameters that lead to reduced production costs are always of interest in industrial developments. In this study, we describe the production of lactic acid at high concentration, yield and volumetric productivity utilizing a novel homofermentative, facultative anaerobe Enterococcus faecalis CBRD01. The highest concentration of 182 g lactic acid l(-1) was achieved after 38 h of fed-batch fermentation on glucose. The bacterial isolate utilized only 2-13% of carbon for its growth and energy metabolism, while 87-98% of carbon was converted to lactic acid at an overall volumetric productivity of 5 g l(-1) h(-1). At 13 h of fermentation, the volumetric productivity of lactate production reached 10.3 g l(-1) h(-1), which is the highest ever reported for microbial production of lactic acid. The lactic acid produced was of high purity as formation of other metabolites was less than 0.1%. The present investigation demonstrates a new opportunity for enhanced production of lactic acid with potential for reduced purification costs.

BACKGROUND CONTEXT Surgical decision making for cervical spondylotic myelopathy (CSM) relies on subjective reports of symptoms and interpretation of physical exam findings. The Romberg test is used to identify balance issues, but has subjective interpretation. When combined with a force plate, the amount and velocity of sway during the Romberg test can be quantified objectively. PURPOSE The study aims to quantify static balance control in myelopathic patients and use this measure for diagnosis and evaluation of disease severity. STUDY DESIGN/SETTING Cross-sectional pilot study. PATIENT SAMPLE Thirty myelopathic patients seen for surgery (mean age of 58±10 years) and 28 normal patients (N=28, mean age 39±7 years). OUTCOME MEASURES Quantitative Romberg measurements from force-plate readings for static balance control. METHODS CSM patients scheduled for surgery who had quantitative balance measurements were identified. Clinical examination findings and imaging results for CSM were reviewed. Quantitative Romberg force plate readings with eyes open and closed were obtained and changes in balance measurements were compared to a normal population (N=28, mean age 39±7 years). RESULTS We identified 30 CSM patients with a mean age of 58±10years. Majority of patients presented with pain (90%) and neurologic symptoms (83%). Cord compression identified in magnetic resonance imaging (MRI) or in CT myelograms, was reported in 90%; only 20% had T2 cord signal changes on MRI. Mean eyes closed Romberg measurements were larger compared to eyes open measurements in CSM patients [p CONCLUSIONS Static balance can be quantified in patients with CSM and is worse when compared to a normal population. Long tract signs and cord compression in imaging translates to worsening balance in myelopathic patients. The use of quantitative Romberg measurements may help diagnose and evaluate progression of CSM.

The abilities of the extreme thermophilic bacterium Caldicellulosiruptor saccharolyticus DSM 8903 to ferment switchgrass (SWG), microcrystalline cellulose (MCC) and glucose to hydrogen (H 2 ) in one-step were examined. Hydrogen production from glucose reached the theoretical maximum for dark fermentation of 4 mol H 2 /mol glucose. The H 2 yield on MCC and SWG after 6 days of fermentation was 23.2 mmol H 2 /L or 9.4 mmol H 2 /g MCC and 14.3 mmol H 2 /L or 11.2 mmol H 2 /g SWG, respectively. The rate of H 2 formation however was higher on MCC (0.7 mmol/L h) than SWG (0.1 mmol/L h). C. saccharolyticus DSM 8903 was able to produce H 2 directly from mechanically-comminuted SWG without any physicochemical or biological pretreatment. Combining four processing steps (pretreatment, enzyme production, saccharification and fermentation) into a single biorefinery operation makes C. saccharolyticus DSM 8903 a promising candidate for consolidated bioprocessing (CBP) of lignocellulosic biomass.

Lichens are composite organisms consisting of a symbiotic association of a fungus (the mycobiont) with a photosynthetic partner (the phytobiont), usually either a green alga or cyanobacterium. The morphology, physiology and biochemistry of lichens are very different from those of the isolated fungus and alga in culture. Lichens occur in some of the most extreme environments on the Earth and may be useful to scientists in many commercial applications.Over the past 2 decades, there has been a renewed and growing interest in lichens as a source of novel, pharmacologically active biomolecules. This review summarizes the past and current research and development trends in the characterization and use of lichens and their bioactive compounds in traditional medicine and other biopharmaceutical applications of commercial interest.The present review contains 10 illustrations and 188 references compiled from major databases including Science Direct, Chemical Abstracts, PubMed and Directory of Open Access Journals.Lichen morphology, symbiosis, diversity and bioactivities including enzyme inhibitory, antimicrobial, antifungal, antiviral, anticancer, anti-insecticidal and antioxidant actions were reviewed and summarized. Recent progress in lichens and lichen-forming fungi was discussed with emphasis on their potential to accelerate commercialization of lichen-based products.Lichens are an untapped source of biological activities of industrial importance and their potential is yet to be fully explored and utilized. Lichen-derived bioactive compounds hold great promise for biopharmaceutical applications as antimicrobial, antioxidant and cytotoxic agents and in the development of new formulations or technologies for the benefit of human life.

Response surface methodology (RSM) was used to optimize the enzymatic hydrolysis of corn stover (CS), an abundant agricultural residue in the USA. A five-level, three-variable central composite design (CCD) was employed in a total of 20 experiments to model and evaluate the impact of pH (4.1–6.0), solids loadings (6.6–23.4%), and enzyme loadings (6.6–23.4 FPU g−1 DM) on glucose yield from thermo-mechanically extruded CS. The extruded CS was first hydrolyzed with the crude cellulase of Penicillium pinophilum ATCC 200401 and then fermented to ethanol with Saccharomyces cerevisiae ATCC 24860. Although all three variables had a significant impact, the enzyme loadings proved the most significant parameter for maximizing the glucose yield. A partial cubic equation could accurately model the response surface of enzymatic hydrolysis as the analysis of variance (ANOVA) showed a coefficient of determination (R2) of 0.82. At the optimal conditions of pH of 4.5, solids loadings of 10% and enzyme loadings of 20 FPU g−1 DM, the enzymatic hydrolysis of pretreated CS produced a glucose yield of 57.6% of the glucose maximum yield which was an increase of 10.4% over the non-optimized controls at zero-level central points. The predicted results based on the RSM regression model were in good agreement with the actual experimental values. The model can present a rapid means for estimating lignocellulose conversion yields within the selected ranges.

Hydrogen (H2) is considered an alternative fuel of the future due to its high energy density and non-polluting nature. H2 energy provides many advantages over fossil fuels in that it is renewable, eco-friendly, and efficient. The global demand for H2 is increasing significantly; however, matching the supply of cost-competitive H2 to meet the current demand is a major technological barrier. H2 can be produced from lignocellulosic biomass and serve as a raw material for the synthesis of many industrially important chemicals. The use of thermophilic bacteria for biological production of H2 appears to be a promising alternative route to the current H2 production technologies. However, the carbon and H2 production metabolisms in most thermophilic bacteria have not yet been completely understood. This paper summarizes the recent research progress made toward understanding the carbon utilization for H2 production and developing gene manipulation techniques to enhance the H2 production capabilities in thermophilic bacteria. It reviews the current status, future directions and opportunities that thermophiles can offer to enable a cost-competitive and environmentally benign H2 production bioprocess.

A recently discovered thermophilic isolate, Geobacillus sp. R7, was shown to produce a thermostable cellulase with a high hydrolytic potential when grown on extrusion-pretreated agricultural residues such corn stover and prairie cord grass. At 70°C and 15-20% solids, the thermostable cellulase was able to partially liquefy solid biomass only after 36 h of hydrolysis time. The hydrolytic capabilities of Geobacillus sp. R7 cellulase were comparable to those of a commercial cellulase. Fermentation of the enzymatic hydrolyzates with Saccharomyces cerevisiae ATCC 24860 produced ethanol yields of 0.45-0.50 g ethanol/g glucose with more than 99% glucose utilization. It was further demonstrated that Geobacillus sp. R7 can ferment the lignocellulosic substrates to ethanol in a single step that could facilitate the development of a consolidated bioprocessing as an alternative approach for bioethanol production with outstanding potential for cost reductions.

Switchgrass (Panicum virgatum), a perennial grass native to North America, is a promising energy crop for bioethanol production. The aim of this study was to optimize the enzymatic saccharification of thermo-mechanically pretreated switchgrass using a thermostable cellulase from Geobacillus sp. in a three-level, four-variable central composite design of response surface methodology. Different combinations of solids loadings (5 to 20%), enzyme loadings (5 to 20 FPU g-1 DM), temperature (50 to 70 oC), and time (36 to 96 h) were investigated in a total of 30 experiments to model glucose release from switchgrass. All four factors had a significant impact on the cellulose conversion yields with a high coefficient of determination of 0.96. The use of higher solids loadings (20%) and temperatures (70 oC) during enzymatic hydrolysis proved beneficial for the significant reduction of hydrolysis times (2.67-times) and enzyme loadings (4-times), with important implications for reduced capital and operating costs of ethanol production. At 20% solids, the increase of temperature of enzymatic hydrolysis from 50 oC to 70 oC increased glucose concentrations by 34%. The attained maximum glucose concentration of 23.52 g L-1 translates into a glucose recovery efficiency of 46% from the theoretical yield. Following red yeast fermentation, a maximum ethanol concentration of 11 g L-1 was obtained, accounting for a high glucose to ethanol fermentation efficiency of 92%. The overall conversion efficiency of switchgrass to ethanol was 42%.

The composition of thermophilic (60 °C) mixed cellulose-degrading enrichment culture initiated from compost samples was examined by constructing a 16S rRNA gene clone library and the presence of sequences related to Actinobacteria , Bacteroidetes , Chloroflexi , Deinococcus-Thermus , Firmicutes , and Proteobacteria were identified. Eight isolates capable of degrading cellulose, carboxymethyl cellulose (CMC), or ponderosa pine sawdust were identified as belonging to the genera Geobacillus , Thermobacillus , Cohnella , and Thermus . A compost isolate WSUCF1 ( Geobacillus sp.) was selected based on its higher growth rate and cellulase activity compared to others in liquid minimal medium containing cellulose as a source of carbon and energy. Strain WSUCF1 and a previously isolated thermophilic cellulose-degrading deep gold mine strain DUSELR13 ( Bacillus sp.) were examined for their enzyme properties and kinetics. The optimal pH for carboxymethyl cellulase (CMCase) activity was 5.0 for both isolates. The optimum temperatures for CMCase of WSUCFI and DUSELR13 were 70 and 75 °C, respectively. For CMC, the DUSELR13 and WSUCF1 CMCases had K m values of 3.11 and 1.08 mg/ml, respectively. Most remarkably, WSUCF1 and DUSELR13 retained 89% and 78% of the initial CMCase activities, respectively, after incubation at 70 °C for 1 day. These thermostable enzymes would facilitate development of more efficient and cost-effective forms of the simultaneous saccharification and fermentation process to convert lignocellulosic biomass into biofuels.

To date, the majority of world's primary energy is derived from fossil fuels. However, the fossil fuel recourses are in an inevitable decline as energy demand continues to grow exponentially with population growth, urbanization, and improved standards of living. Crude oil prices have recently risen several times and their current annual volatility exceeds 30%. The potential scarcity of fossil fuels has prompted a global search for alternative energy resources. Biodiesel fulfills the major requirements for production of alternative fuels such as feedstock availability, technical feasibility, and economic competitiveness. Together with other renewable biofuels, the use of biodiesel as a substitute of fossil-based fuels is expected to reduce the dependence on imported petroleum and associated political and economic vulnerability, decrease greenhouse gas emissions, and revitalize the economy. The objective of this article was to provide an update of the most recent technological advancements toward clean and sustainable biodiesel production through a thorough overview of biodiesel feedstocks, most promising transesterification processes, and opportunities for glycerol utilization for value-added products. A critical analysis of the techno-economical barriers and environmental challenges that need to be addressed in future R&D efforts toward commercialization and establishment of a sustainable and cost-efficient biodiesel production is provided. Keywords: biodiesel; waste oil; microbial oil; transesterification; microwave irradiation; lipase; glycerol; triacetin; greenhouse gas emissions; trends in biodiesel R&D

Demethylation of industrial lignin has been for long coveted as a pathway to the production of an abundant natural substitute for fossil-oil derived phenol. In an attempt to possibly identify a novel Kraft lignin-demethylating enzyme, we surveyed a collection of fungi by using selected ion flow tube-mass spectrometry (SIFT-MS). This method readily identifies methanol resulting from lignin demethylation activity. Absidia cylindrospora, and unidentified Cylindrocladium sp. and Aspergillus sp. were shown to metabolize lignin via different pathways, based on the HPLC analysis of lignin fragments. Of these three, Cylindrocladium and Aspergillus were shown to retain most of the lignin intact after 3 weeks in culture, while removing about 40% of the available methoxy groups. Our results demonstrate that after optimization of culture and lignin recovery methods, biological modification of Kraft lignin may be a feasible pathway to obtaining demethylated lignin for further industrial use.

Production of xylan-degrading enzymes, endo-β-xylanase (EC 3.2.1.8), β-xylosidase (EC 3.2.1.37), α- l -arabinofuranosidase (EC 3.2.1.55 and α-galactosidase (EC 3.2.1.22) by Aspergillus oryzae NRRL 1808 was investigated in solid-state fermentation using eucalyptus soda-anthraquinone and bagasse soda pulps as carbon feedstock. The impact of different nitrogen sources and initial fermentation pH on enzyme production was studied in medium optimisation experiments using fractional factorial design. The use of ammonium nitrate and corn steep liquor favoured xylanase production on eucalyptus pulp, whereas potassium nitrate and corn steep liquor increased xylanase yields on bagasse pulp. Xylanase production on eucalyptus and bagasse pulps under optimised conditions peaked on day 4 of cultivation (3200 and 2675 IU g−1 dry matter, respectively) which represents an increase in xylanase activity of 60% and 37%, respectively, over the non-opimised conditions. Biobleaching of eucalyptus and bagasse pulps was carried out using the whole fermented material (residual pulp, fungal biomass and in situ enzymes) from the cultivation of A. oryzae without a prior down streaming of the in situ enzymes from these pulps. Overall, the bagasse pulp was more susceptible to enzyme bleaching than eucalyptus pulp. In all instances, a greater brightness gain was induced with the in situ solid-state enzymes (0.9–3.0 points brightness increase) than a commercial enzyme control (0.8–2.5 points). At the same bleaching costs (US$ 1 or 3 t−1 pulp), the solid-state enzymes produced under optimised conditions were 20–36% more efficient in improving the brightness of paper pulp than the commercial enzyme. However, the presence of increased levels of side chain xylan degrading enzymes in the optimised medium did not improve the bleaching abilities of xylanase. It was demonstrated that bagasse pulp could successfully be used as carrier of A. oryzae enzymes in biobleaching of eucalyptus pulp without sacrificing the bleaching efficiency of xylanase.

Metabolic engineering is a powerful biotechnological tool that finds, among others, increased use in constructing microbial strains for higher lactic acid productivity, lower costs and reduced pollution. Engineering the metabolic pathways has concentrated on improving the lactic acid fermentation parameters, enhancing the acid tolerance of production organisms and their abilities to utilize a broad range of substrates, including fermentable biomass-derived sugars. Recent efforts have focused on metabolic engineering of lactic acid bacteria as they produce high yields and have a small genome size that facilitates their genetic manipulation. We summarize here the current trends in metabolic engineering techniques and strategies for manipulating lactic acid producing organisms developed to address and overcome major challenges in the lactic acid production process.

Lignin has a significant and largely unrealized potential as a source for the sustainable production of fuels and bulk high-value chemicals. It can replace fossil-based oil as a renewable feedstock that would bring about socio-economic and environmental benefits in our transition to a biobased economy. The efficient utilization of lignin however requires its depolymerization to low-molecular weight phenolics and aromatics that can then serve as the building blocks for chemical syntheses of high-value products. The ability of laccase to attack and degrade lignin in conjunction with laccase mediators is currently viewed as one of the potential “breakthrough” applications for lignin valorization. Here, we review the recent progress in lignin biodegradation with laccase-mediator systems, and research needs that need to be addressed in this field.

We report here the draft genome sequence of the novel homofermentative Enterococcus faecalis isolate CBRD01, which is capable of high lactic acid productivity and yields, with minimal nutritional requirements. The genome is 2.8 Mbp, with 37% G+C, and contains genes for two lactate dehydrogenase (LDH) enzymes found in related organisms.

Due to the strong and increasing off-shore competition and global movement and incentives for green fuels and chemicals, the pulp and paper industry needs to create additional revenues and diversify their products and markets to remain competitive. The transformation of pulp and paper mills into integrated forest biorefineries (IFBR) would require the development of advanced bio-based processes to bring about economic, environmental and social benefits. The major research needs, technological challenges, potential products derived from the IFBR platforms and models for the complex utilization of forest biomass for biofuels, biochemicals, market pulp and paper products will be presented and discussed.

The global trend for production of biofuels and bioproducts from renewable resources is currently steered by three important drivers: 1) increasing demand and prices of petroleumderived fuel; 2) increasing food needs; and 3) increasing greenhouse gas emissions. Biomass is the single renewable resource that has the potential to supplant the use of liquid transportation fuels now and help create a more stable energy future.

© Springer Science+Business Media B.V. 2012, Prokaryotes commonly present outer cell wall structures composed of a crystalline array of proteinaceous subunits, known as surface layers (S-layers). The ORF encoding the S-layer protein (SlpA) of Lactobacillus brevis was cloned into Lactococcus lactis under the transcriptional control of the xyloseinducible expression system (XIES). SlpA was secreted into the extracellular medium, as determined by immunoblotting, and assays on the kinetics of SlpA production revealed that repression of the system with glucose did not require the depletion of xylose from the medium that allows transitory ORF expression. The successful use of XIES to express S-layer proteins in the versatile and generally recognized as safe species L. lactis opens new possibilities for an efficient production and isolation of SlpA S-layer protein for its various applications in biotechnology and importantly as an antigen-carrying vehicle.

Prairie cordgrass (PCG), Spartina pectinata, is considered an energy crop with potential for bioethanol production in North America. The focus of this study was to optimize enzymatic hydrolysis of PCG at higher solids loadings using a thermostable cellulase of a mutant Penicillium pinophilum ATCC 200401. A three variable, five-level central composite design of response surface methodology (RSM) was employed in a total of 20 experiments to model and evaluate the impact of pH (4.1–6.0), solids loadings (6.6%–23.4%), and enzyme loadings (6.6–23.4 FPU/g dry matter, DM) on glucose yield from a thermo-mechanically extruded PCG. The extruded PCG was first hydrolyzed with the crude P. pinophilum cellulase and then fermented to ethanol with Saccharomyces cerevisiae ATCC 24860. Although all three variables had a significant impact, the enzyme loadings proved the most significant parameter for maximizing the glucose yield. A partial cubic equation could accurately model the response surface of enzymatic hydrolysis as the analysis of variance showed a coefficient of determination (R2) of 0.89. At the optimal conditions of pH of 4.5, solids loadings of 10% and enzyme loadings of 20 FPU/g DM, the enzymatic hydrolysis of pretreated PCG produced a glucose yield of 76.1% from the maximum yield which represents an increase of 15% over the non-optimized controls at the zero-level central points. The predicted results based on the RSM regression model were in good agreement with the actual experimental values. The model can present a rapid means for estimating lignocellulose conversion yields within the selected ranges. Furthermore, statistical optimization of solids and enzyme loadings of enzymatic hydrolysis of biomass may have important implications for reduced capital and operating costs of ethanol production.

Mild oxidation of amidine (1) bearing two sterically crowded phenol moieties leads to the formation of the dispirocyclohexadienone derivative (6) of pyrrolidin-2,5-dione N-arylamine through an intramolecular ring closure recombination of the intermediate biradical (4).

Mild oxidation of amidine (1) bearing two sterically crowded phenol moieties leads to the formation of the dispirocyclohexadienone derivative (6) of pyrrolidin-2,5-dione N-arylamine through an intramolecular ring closure recombination of the intermediate biradical (4).