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In this work, a modification method of H3PO4 plus H2O2 (PHP) was introduced to targetedly form abundant oxygenated functional groups (OFGs) on biochar, and methylene blue (MB) was employed as a model pollutant for adsorption to reflect the modification performance. Results indicated that parent biochars, especially derived from lower temperatures, substantially underwent oxidative modification by PHP, and OFGs were targetedly produced. Correspondingly, approximately 21.5-fold MB adsorption capacity was achieved by PHP-modified biochar comparing with its parent biochar. To evaluate the compatibility of PHP-modification, coefficient of variation (CV) based on MB adsorption capacity by the biochar from various precursors was calculated, in which the CV of PHP-modified biochars was 0.0038 comparing to 0.64 of the corresponding parent biochars. These results suggested that the PHP method displayed the excellent feedstock compatibility on biochar modification. The maximum MB adsorption capacity was 454.1 mg/g when the H3PO4 and H2O2 fraction in PHP were 65.2% and 7.0%; the modification was further intensified by promoting temperature and duration. Besides, average 94.5% H3PO4 was recovered after 10-batch modification, implying 1.0 kg H3PO4 (85%) in PHP can maximally modify 2.37 kg biochar. Overall, this work offered a novel method to tailor biochar towards OFGs-rich surface for efficient adsorption.

Staphylococcus aureus is a species of Staphylococcus and belongs to Gram-positive. Meanwhile, S. aureus remains one of the most common nosocomial and community-acquired infections, causing blood flow, skin, soft tissue, and lower respiratory tract infections.

To convert lignin into high-valued carbon materials and understand the lignin structure function, oxidized lignin, a by-product from lignocellulose PHP-pretreatment (phosphoric acid plus hydrogen peroxide), was carbonized by one-step KOH-activation; the physico-chemical characteristics and electrochemical performances of the harvested carbons were also investigated. Results indicated the resultant carbons displayed 3-dimensional hierarchical porous morphology with maximum specific surface area of 3094 m2 g−1 and pore volume of 1.72 cm3 g−1 using 3:1 KOH/lignin ratio for carbonization. Three-electrode determination achieved a specific capacitance of 352.9 F g−1 at a current of 0.5 A g−1, suggesting a superior rate performance of this carbon. Two-electrode determination obtained an excellent energy density of 9.5 W h kg−1 at power density of 25.0 W kg−1. Moreover, 5000 cycles of charge/discharge reached 88.46% retention at 5 A g−1, implying an outstanding cycle stability. Basically, low molecular weight and abundant oxygen-containing functional groups of employed lignin mainly related to the excellent porous morphology and the outstanding electrochemical performances, suggesting the oxidized lignin was an ideal precursor to facilely prepare activated carbon for high-performance supercapacitor. Overall, this work provides a new path to valorize lignin by-product derived from oxidative pretreatment techniques, which can further promote the integrality of lignocellulose biorefinery.

Cellulose from lignocellulosic biomass is the most promising renewable feedstock which may become a substitute for petrochemical products. However, it is challenging to extract cellulose from biomass because of the structural resistance of lignocellulose. Phosphoric acid plus hydrogen peroxide (PHP) pretreatment is an efficient approach that might be applied to get the cellulose-enriched fraction (CEF) from biomass. This study employed the artificial neural network (ANN) to predict the PHP pretreatment efficiency. The critical conditions, including pretreatment time (t), temperature (T), H3PO4 concentration (Cp), and H2O2 concentration (Ch), were employed as input variables for the ANN model to predict the output variables: cellulose content (C-C), cellulose recovery (C-Ry), hemicellulose removal (H-Rl), and lignin removal (L-Rl). The key parameters of ANN models are selected depending on the root mean square errors (RMSE). ANN models' final optimal topological structure contains one hidden layer with 9, 10, 10, and 12 neurons for C-C, C-Ry, H-Rl, and L-Rl, respectively. The actual testing data fit the predicted data with an R2 of 0.8070–0.9989. Additionally, we computed the relative importance (RI) of input variables on output variables using the Garson equation with net weight matrixes. And the results revealed that Cp and Ch (RI 12.0–62.6%) impacted the effectiveness of PHP pretreatment primarily. T (RI 78.6%) dominates the removal efficacy of hemicellulose, and t (RI 9.5–24.6%) has less influence compared to the other conditions. The study provides insights into the optimization of biomass pretreatment.

Bacterial cellulose (BC), harvested from the hydrolysate of starch-rich solid in kitchen waste (KW), was employed to prepare a superhydrophobic stearic acid (SA)-modified BC aerogel (S-BCA) for coo...

To improve the electrochemical properties of lignocellulose-derived carbon, wheat straw was hydrothermally processed at different temperatures followed by KOH activation for the preparation of porous carbons. Their physical, chemical, and electrochemical properties were analyzed to clarify the effects of hydrothermal processing. The results indicated that high-temperature hydrothermal processing fragmented the wheat straw and increased the heteroatoms content to make the hydrochars more conducive to activation, thereby improving the specific surface area, N-heteroatoms and phenolic hydroxyl groups of activated carbons. A maximum specific surface area of 2034.4 m

Objective: To investigate the changes and significance of humoral immunity, myocardial damage, trace elements and inflammatory factors levels in children with rotavirus enteritis. Methods: One hundred children with rotavirus enteritis admitted to our hospital from January 2019 to December 2020 were retrospectively selected as the case group, and they were divided into a no dehydration group (33 cases), mild dehydration group (41 cases), and moderate dehydration group (26 cases). Another 100 children with rotavirus-negative enteritis during the same period were selected as the control group. Serum immunoglobulin, cardiac enzyme profile, trace elements, and interleukin-6 (IL-6) levels were compared between the two groups, and among the case groups for different degrees of dehydration. Results: Serum immunoglobulin A (IgA), immunoglobulin G (IgG), immunoglobulin M (IgM), zinc, magnesium, and calcium in the case group were lower than in controls (P

Bacterial cellulose (BC), a fascinating and renewable polymer, can be applied widely in various bio-based materials. However, its synthesis is generally limited by medium acidosis. Herein, we demonstrated a built-in galvanic cell within the BC fermentation medium to alleviate the acidosis, by which BC yield was promoted by 191%, and simultaneously the yield of electrical power of 0.68 W to 8.10 W during the incubation.

Biochars produced from crab shell (CSB), oak sawdust (OB), Jerusalem artichoke tuber (JAB) and sorghum grain (SB) displayed distinguishable adsorption-related characteristics, such as specific surface area (SSA), ash content and acidic oxygen-containing functional groups (AFGs), which linked to the biochar adsorption mechanisms of most pollutants. Herein, PO43–, Cd2+, and nitrobenzene (NB) were employed for adsorption by these biochars to elucidate the dominant factors for the adsorption. Adsorption performance of the three pollutants onto these four biochars varied considerably, as exemplified by the excellent adsorption of PO43– and Cd2+ onto CSB (225.3 and 116.0 mg/g, respectively) as compared with onto the other three biochars (4.2–37.1 mg/g for PO43– and 9.7–41.0 mg/g for Cd2+). OB displayed the best adsorption of NB (72.0 mg/g), followed by SB (39.5 mg/g), JAB (31.1 mg/g), and CSB (23.6 mg/g). The kinetics and isotherm adsorption assessments couple with material characterization suggested that the sorption of selected pollutants on biochars was attributed to the multiple mechanisms involved, including coprecipitation, chemical bonds, cation exchange, physical absorption, and complexation. Further path analysis suggested that AFGs and ash content in biochars were more important than SSA with regards to pollutant removal, especially, with ash playing a crucial role in the removal of Cd2+ and PO43–, and AFGs being mainly responsible for NB adsorption. These findings might offer guidance on the preparation or modification of biochar with a targeted function for pollutant removal through an understanding the dominant factors.

The abundantly released tail-gas from lignocellulose pretreatment with phosphoric acid plus hydrogen peroxide (PHP) was found to accelerate the aging of latex/silicone textural accessories of the pretreatment device. Inspired by this, tail-gas was utilized to control organic pollutants. Methylene blue (MB), as a model pollutant, was rapidly decolorized by the tail-gas, and oxidative degradation was substantially proven by full-wavelength scanning with a UV–visible spectrometer. The tail-gas from six typical lignocellulosic feedstocks produced 68.0–98.3% MB degradation, suggesting its wide feedstock compatibility. Three other dyes, including rhodamine B, methyl orange and malachite green, obtained 97.5–99.5% degradation; moreover, tetracycline, resorcinol and hexachlorobenzene achieved 73.8–93.7% degradation, suggesting a superior pollutant compatibility. In a cytotoxicity assessment, the survival rate of the degraded MB was 103.5% compared with 80.4% for the untreated MB, implying almost no cytotoxicity after MB degradation. Mechanism investigations indicated that the self-exothermic reaction in PHP pretreatment drove the self-generated peroxy acids into tail-gas. Moreover, it heated the pollutant solution and thermally activated peroxy acids as free radicals for efficient pollutant degradation. Here, a brand-new technique for degrading organic pollutants with a “Win–Win–Win” concept was purposed for lignocellulose valorization, pollutant control by waste tail-gas, and biofuel production.

Objective Cardiac diseases lead to heart failure (HF), but the progression can take several years. Using blood samples to monitor changes in the heart before clinical symptoms begin may help to improve patient management. Methods Microarray data GSE42955 and GSE9128 were used as study datasets and GSE16499, GSE57338, and GSE59867 were used as validation groups. The “limma” package from R Language was used to identify differentially expressed genes. Functional enrichment analyses of gene ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways were performed using Database for Annotation, Visualization and Integrated Discovery. We also investigated the correlation between the heart and blood using the mRNA expression level. Results Three hub genes, CD14, CD163, and CCR1, were identified. Functional enrichment analyses showed their involvement in the immune response and in the inflammatory response, which are the critical biochemical processes in ischemic HF. The mRNA expression level further demonstrated that a special model may exist to help to predict the mRNA level in the heart based on that in blood. Conclusions Our study identified three biomarkers that can connect the heart and blood in ischemic heart diseases, which may be a new approach to help better manage ischemic cardiac disease patients.

An effective pretreatment to improve cellulose accessibility and facilitate glucose release is crucial in a cellulosic ethanol biorefinery. This work comparatively assessed four H2O2-involved pretreatments, i.e., concentrated H3PO4 plus H2O2 (PHP), H2O2–CH3COOH (HPAC), alkaline-H2O2 (AHP), and Fenton chemistry (FC), for their pretreatment performances on wheat straw, poplar, and birch biomass. Substrate characteristics before and after pretreatment were assessed using SEM, XRD, and LSCM. The hydrolytic potentials of the pretreated substrates were compared by Simons’ stain and cellulose–glucose conversion assessment. The results showed that acidic H2O2-involved pretreatments (PHP and HPAC) were more efficient in biomass delignification compared to AHP and FC. PHP pretreatment is more promising for cellulosic ethanol production due to its corresponding high glucose yield (368.0 mg g−1) after enzymatic hydrolysis.

Background Cow's milk protein allergy (CMPA) is commonly seen in children. There have been no reports of the true prevalence of CMPA in Chinese infants. The aim of this population-based study is to determine the prevalence, clinical characteristics, and outcome of CMPA in Chinese infants. Methods We carried out a prospective survey in 7 participating hospitals throughout southern China. We included infants ≤12 months of age during the survey. For those suspected of CMPA, oral food challenge with cow's milk protein (CMP) was performed. A follow-up telephone interview was conducted at 12 months after the diagnosis to assess the clinical outcome of CMPA. Results A total of 9910 questionnaire surveys were distributed and 7364 (74.3%) were returned. The eligible survey number of surveys was 6768 (91.9%). A total of 182 infants was confirmed with CMPA, including 13 with anaphylactic reactions, 28 with clinical symptoms and serum immunoglobulin E (sIgE) >3.5 IU/mL, and 141 with positive CMP challenge test. The prevalence of CMPA was 2.69%. Infants with confirmed CMPA had significantly stronger family history of either 1 or both parents with food allergy, higher Cesarean section rate, and lower rate of breastfeeding, compared with those without CMPA. At 12-month telephone follow-up of 176 CMPA infants, 136 infants (77.3%) had become tolerant to CMP. Conclusions The prevalence of CMPA was 2.69%. CMPA infants had a strong family history of food allergy and atopy. Both Cesarean delivery and formula feeding were risk factors for CMPA. At 12-month follow-up, the majority of CMPA infants had become tolerant to CMP.

Two varieties of grain sorghum, including Chuannuo (CN) and Luzhouhong (LZH), were attempted on heavy metal (HM−) contaminated farmland. HMs distribution in the harvested biomasses, including grain and stover (leaf + stalk), were analyzed. The mostly HM-accumulated part was anaerobically digested to check the biogas releasing performances, and the fates of HMs in digestion. Results indicated the bioconcentration factors were lower than 1, suggesting these investigated varieties were characterized by lower accumulation on HMs. The accumulated HMs mainly existed in stover, in detail, 80.9% (Cu), 71.4% (Pb), 97.8% (Cr) and 99.1% (Cd) were in CN, and the corresponding HM was 78.4%, 85.1%, 98.9% and 97.8%, respectively, in LZH. Anaerobic digestion of stover were performed well with methane yield of 173.78 mL/g VS and 144.73 mL/g VS for CN and LZH, respectively. After digestion, more than 99% HMs were retained in solid residues, in which the residual state HMs were increased by 7–38%. Besides, the decreased mobility (except Cu) and bioavailability after anaerobic digestion implied these HMs tended to be more stable in the digested solid residues.

As a newly-developed method for pretreating lignocellulosic biomass, phosphoric acid plus hydrogen peroxide (PHP) was employed as a pretreatment solvent to fractionate wheat straw. The structural properties of the derived lignin were elucidated in particular. Results indicated that 100.0 g of wheat straw (dry basis) yielded 39.7 g of cellulose-rich fraction, 4.7 g of oligosaccharides, and 4.5 g of lignin at mild conditions of 50 °C within 1.0 h. The resultant cellulose-rich fraction was highly accessible to hydrolytic enzymes with 88–96% cellulose–glucose conversion in 24 h, suggesting a great potential for producing biofuels. The derived lignin was characterized as having high purity (≤1.0% residual carbohydrates) and relatively low molecular weight (Mw < 1436 g mol–1) and being abundant in carboxylic acid functional groups. According to the 31P, 13C, and 2D heteronuclear single quantum coherence nuclear magnetic resonance spectroscopy results on the derived lignin, the degree of condensation was quite l...

Phosphoric acid plus hydrogen peroxide (PHP) pretreatment was employed on wheat straw for ethanol conversion by simultaneous saccharification and fermentation (SSF) at high loadings. Results showed solid loading of PHP-pretreated wheat straw can be greatly promoted to 20%. Although more enzyme input improved ethanol conversion significantly, it still can be potentially reduced to 10–20 mg protein/g cellulose. Increasing yeast input also promoted ethanol conversion, however, the responses were not significant. Response surface method was employed to optimize SSF conditions with the strategy of maximizing ethanol conversion and concentration and minimizing enzyme and yeast input. Results indicated that ethanol conversion of 88.2% and concentration of 69.9 g/L were obtained after 120 h SSF at solid loading of 15.3%, and CTec2 enzyme and yeast were in lower input of 13.2 mg protein/g cellulose and 1.0 g/L, respectively. Consequently, 15.5 g ethanol was harvested from 100 g wheat straw in the optimal conditions.

Xylan, de-alkaline lignin and microcrystalline cellulose were employed as representative models of hemicellulose, lignin and cellulose in lignocellulosic biomass. These three model compounds, together with the real-world biomass, wheat straw were pretreated using the newly developed PHP pretreatment (concentrated phosphoric acid plus hydrogen peroxide) to better understand the structural changes of the recovered solid and chemical fractions in the liquid. Results showed that almost all xylan and higher than 70% lignin were removed from wheat straw, and more than 90% cellulose was recovered in the solid fraction. The pretreated model xylan recovered via ethanol-precipitation still maintained its original structural features. The degree of polymerization of soluble xylooligosaccharides in liquid was reduced, resulting in the increase of monomeric xylose release. Further xylose oxidization via the path of 2-furancarboxylic acid → 2(5H)-furanone → acrylic acid → formic acid was mainly responsible for xylan degradation. The chemical structure of de-alkaline lignin was altered significantly by PHP pretreatment. Basic guaiacyl units of lignin were depolymerized, and aromatic rings and side aliphatic chains were partially decomposed. Ring-opening reactions of the aromatics and cleavage of C-O-C linkages were two crucial paths to lignin oxidative degradation. In contrast to lignin, no apparent changes occurred on microcrystalline cellulose. The reason was likely that acid-depolymerization and oxidative degradation of cellulose were greatly prevented by the formed cellulose phosphate.

A newly developed PHP (phosphoric acid plus hydrogen peroxide) pretreatment for lignocellulose is integrated to be a multi-product platform for bioethanol, lignin, and ultra-high surface area carbon; the performances of this multi-product strategy are investigated in this work. Based on PHP pretreatment platform, 100.0 g wheat straw yield 16.0 g ethanol from the cellulose fraction, and 7.2 g high purity lignin can be recovered from the derived liquid fraction in pretreatment. Activated carbon (PHPK-800) with ultra-high surface area of 3291 m2 g−1 can be produced from the water-soluble fractions derived from pretreatment. As electrode material for supercapacitor, PHPK-800 displays an excellent specific capacitance of 303.5 F g−1 at 0.5 A g−1, and retains 87.0% of initial specific capacitance with more than 95.0% coulomb efficiency after 5000 cycles. The fabricated symmetric supercapacitor harvests an excellent energy density of 13.2 Wh kg−1 with 199.9 W kg−1 power density. Besides, a superior CO2 adsorption capability of 4.61 mmol g−1 is achieved by activated carbon of PHPK-700. According to these performances, PHP pretreatment platform is promising for converting lignocellulose into bioethanol, lignin and carbons by the biomass full utilization to achieve a more sustainable lignocellulosic refinery.

In order to evaluate the effects of La-involvement on biomass pyrolysis behaviors and properties of produced biochar, oak sawdust (OS) and corn straw (CS) were employed for thermogravimetric-differential thermogravimetric (TG-DTG) analysis and producing biochar with/without La-involvement. Results indicated the initial and final temperatures were shifted toward lower temperature as LaCl3 was involved in pyrolysis. Mass loss and average mass loss rate during pyrolysis decreased with La-involvement. The kinetics indicated that the first-order reaction kinetic model well matched the pyrolysis process. As La-involved OS and CS were employed, their apparent activation energies (Ea) were reduced, and their pyrolysis characteristic index (I) were higher comparing with the OS and CS without La-involvement. Based on the produced biochar, the yield and ash content were increased by La-involvement, and the O/C ratio and iodine sorption value (ISV) were also enhanced. Obviously, the loaded LaCl3 could facilitate pyrolysis process, and the produced biochar exhibited a great adsorption potential in aqueous solution. According to the results from FT-IR (Fourier transform infrared spectroscopy) analysis, La in pyrolysis functioned as accelerating lignin decomposition via condensing –OH, breaking aliphatic C–H and aromatic rings on lignin, cutting the links of C-O-C among the monomers in lignocellulose. LaCl3 was finally converted to La2O3 in biochar after pyrolysis.

Effective valorization of lignin is crucial to achieve a sustainable, economic and competitive biorefinery of lignocellulosic biomass. In this work, an integrated process was proposed based on a concentrated phosphoric acid plus hydrogen peroxide (PHP) pretreatment to simultaneously facilitate cellulose digestibility and modify lignin as adsorbent. As a dominant constitutor of PHP pretreatment, H2O2 input and its influence on the overall fractionation/lignin modification performance was thoroughly investigated. Results indicated that wheat straw was fractionated more efficiently by increasing the H2O2 input. H2O2 input had a significant influence on the digestibility of the obtained cellulose-rich fraction whereby almost 100.0% cellulose-glucose conversion can be achieved even with only 0.88% H2O2 input. Besides, the adsorption capacity of lignin on MB was improved (74.3 to 210.1 mg g&minus, 1) due to the oxidative-modification in PHP pretreatment with H2O2 inputs. Regression analysis indicated that &ndash, COOH groups mainly governed the lignin adsorption (R2 = 0.946), which displayed the considerable adsorption capacities for typical cationic substances. This work shows a promising way to integrate the lignin modification concept into the emerging PHP pretreatment process with the dual goal of both cellulose utilization and lignin valorization.

Acute liver injury is a life-threatening syndrome that often caused by hepatocyte damage and is characterized by inflammatory and oxidative responses. Helenalin isolated from Centipeda minima (HCM) has been found to have anti-inflammatory and anti-oxidative effects. Here, this study aimed to investigate the effects and underlying mechanisms of HCM on Lipopolysaccharide/D-Galactosamine (LPS/D-GalN)-induced acute liver injury. Mice were intragastrically administered with various dose of HCM for 10 days; 2 h after the final treatment, the mice were injected with 50 μg/kg LPS and 800 mg/kg D-GalN. The histopathological changes, hepatocyte apoptosis, serum cytokines, oxidative stress and inflammatory cytokines were assessed. The results showed that HCM significantly ameliorated the hepatic injury, as evidenced by the attenuation of histopathological changes and the decrease in serum aminotransferase and total bilirubin activities. HCM markedly decreased hepatocyte apoptosis by modulating the mitochondria-dependent pathway, including the increase in the Bcl-2/Bax ratio, the inhibition of caspase-3, -8 and -9, and the inhibition of cytochrome C release. Moreover, HCM strongly alleviated oxidative stress, lipid peroxidation and reactive oxygen species (ROS) generation by activating the Nrf2 signaling pathway. In addition, HCM significantly attenuated inflammatory cytokines including TNF-α, IL6 and IL-1β as well as NO production by inhibiting TLR4 signaling transduction and NF-κB activation. In conclusion, HCM protects hepatocytes from damage induced by LPS/D-GalN, which may contribute to its ability to alleviate hepatocyte apoptosis by protecting the mitochondrial function, inhibit oxidative stress by activating the Nrf2 pathway, and attenuate inflammation by inhibiting NF-κB activation. This study demonstrates that HCM may be developed as a potential agent for the treatment of acute liver failure.

Disposal of kitchen wastes (KW) by anaerobic digestion (AD) is popular for many currently running projects, but the discharged residual solid fraction from three-phase separation is challenging the AD process in the real world. To cope with the challenge, a multi-product strategy, including bacterial cellulose (BC) production and vermicomposting, was integrated into the currently running AD process to be a new process; the as-prepared biochar from vermicompost was attempted in AD to promote the digestion performances. Experiential investigations on the multi-product strategy, LCA (life cycle assessment) and economic assessment on the integrated process were performed to clarify the technical compatibility, environmental sustainability, and economic profitability. Results showed that 1.0 t kW (wet basis) yielded 4.5 kg earthworm biomass, 20.0 kg vermicompost, and 0.8 kg BC (dry basis), suggesting the multi-product strategy was compatible to the valorization of residual solid fraction. Cumulative CH4 was promoted by 31.0% via adding as-prepared biochar in AD of liquid fraction from separation and effluent from BC fermentation, indicating the technical compatibility of the techniques of BC production, vermicomposting and AD. LCA demonstrated the newly integrated process reduced the GWP (Global Warming Potential) and AP (Acidification Potential) emission by 40.9% and 130.0%; net output of PED (Primary Energy Demand) increased by 32.8%, suggesting its environmental sustainability was promoted comparing to the currently running process. Besides, 3.0% promotion on the net revenue of the newly integrated process implied the increased profitability. As a result, the newly integrated process will be a step forward towards a more sustainable management on KW.

Trichoderma is cultivated on a solid medium prepared from wheat straw and food waste. The harvested mixture is fully used to prepare high specific surface carbon. The carbon is further assembled into an electrode to assess its electrochemical performance as a supercapacitor. As adjusted by the activation temperature, the carbon derived at 800 °C displays an extremely high specific surface area of 3977.3 m2 g−1, and the carbon derived at 900 °C shows a large pore volume of 2.372 cm3 g−1. Correspondingly, an excellent specific capacitance of 409.7 F g−1 at a current density of 0.5 A g−1 can be achieved in a three-electrode system. The symmetric supercapacitor achieves a high energy density of 11.3 Wh kg−1 with a corresponding power density of 240.0 W kg−1, and exhibits a good capacitance retention of 99.2% after 10000 cycles at the current density of 5 A g−1 in a 6.0 mol L−1 KOH electrolyte. Based on these results, a novel low-cost path for preparing high-performance materials for energy storage applications is achieved from real-world biomass sources and provides new insights to realize the full utilization of biomass waste.

Anaerobic digestion of food waste is operationally challenged by rapid over-acidification. Bottom ash, a largely abandoned solid waste from biomass power generation, was supplemented in the anaerobic digestion of 2 typical food wastes of kitchen waste and fruit/vegetable waste for an attempt on this challenge. Results indicated no methane was recorded in anaerobic digestion of only food waste, indicating a complete failure by over-acidification. When bottom ash was involved, the digestion performances were significantly improved with the cumulative methane of 431.63 mL/g and 428.59 mL based on 1.0 g total solid of kitchen waste and fruit/vegetable waste. It was found that the digestate pH was stabilized to approximately 7.5 during the digestion of these food wastes because of the excellent buffering capacity of bottom ash to the derived volatile fatty acids, indicating a main contributor to the improvement. 47.9%–71.8% promotion on digestate conductivity and the obviously enriched Methanosarcina abundance also were observed, suggesting the intensified direct interspecific electron transfer; this also had a contribution to the improved digestion. Technically, it can be proposed as a novel solution to valorization of bottom ash via facilitating the efficient anaerobic digestion of food wastes, by which a “Win-Win” strategy for these 2 bioenergy industries can be achieved to make them more sustainable.

In this work, the whole biomass of sweet sorghum [Sorghum bicolor (L.) Moench], including the sugar-rich juice and lignocellulosic parts (root, stalk, and leaf), was individually investigated as carbon sources for bacterial cellulose (BC) production. The juice part was employed directly, and the lignocellulosic parts were pretreated by PHP (phosphoric acid plus hydrogen peroxide) to yield the fermentable sugar for BC production. Results indicated that the BC yield from the root (2.28 g/L), stalk (1.82 g/L), and leaf (2.54 g/L) was 1.86–2.59-fold higher than the commercial d -glucose medium (0.98 g/L), and a comparable BC yield (0.87 g/L) also can be obtained from the juice. The structural properties of BC from the lignocellulosic parts were similar to those from the d -glucose medium. The tensile strength of BC obtained from the stalk and leaf was 8.24 MPa and 4.83 MPa, respectively, which was superior to that of the glucose medium (2.07 MPa). Considering the huge biomass yield of sweet sorghum, the present work broadens the “energy crop” sweet sorghum as a “material crop” towards a new biorefinery concept for material building blocks.

Acid-buffering of VCBC and VC was evaluated using 4 VFAs, and their application on anaerobic digestion of CM and KW was investigated. Results indicated acid-buffering capacity of VCBC to acetic, propionic, butyric, and valeric acid was 2.5, 1.1, 1.9 and 1.6-fold higher comparing with VC. CM digestion was not initiated at higher organic loading of 50 g TS/kg, while it worked well with 5.0% VCBC or VC. KW was not digested even though VC or VCBC was increased to 15% and 20%. However, KW digestion can be alleviated with increasing VCBC or VC proportion, in which the alleviation by VCBC was better than VC. Average VFAs concentration during CM digestion with VC was 4077.7 mg/L comparing with 2835.8 mg/L of VCBC, and biogas release was delayed for 10-days accompanying rapid pH decrease in CM digestion with VC, which reflected acid-buffering of biochar played a crucial role on improving anaerobic digestion.

Wheat straw was pretreated by phosphoric acid plus hydrogen peroxide (PHP), in which temperature, time, and H3PO4 proportion for pretreatment were investigated by using response surface method. Results indicated that hemicellulose and lignin removal positively responded to the increase of pretreatment temperature, H3PO4 proportion, and time. H3PO4 proportion was the most important variable to control cellulose recovery, followed by pretreatment temperature and time. Moreover, these three variables all negatively related to cellulose recovery. Increasing H3PO4 proportion can improve enzymatic hydrolysis; however, reduction on cellulose recovery results in decrease of glucose yield. Extra high temperature or long time for pretreatment was not beneficial to enzymatic hydrolysis and glucose yield. Based on the criterion for minimizing H3PO4 usage and maximizing glucose yield, the optimized pretreatment conditions was 40 °C, 2.0 h, and H3PO4 proportion of 70.2 % (H2O2 proportion of 5.2 %), by which glucose yielded 299 mg/g wheat straw (946.2 mg/g cellulose) after 72-h enzymatic hydrolysis.

Objective To investigate the relationship between peroxisome proliferator-activated receptor gamma (PPARγ) mRNA, serum adiponectin (ADP) and lipids in paediatric patients with Kawasaki disease (KD). Methods This prospective study enrolled paediatric patients with KD and grouped them according to the presence or absence of coronary artery lesions (CAL). A group of healthy age-matched children were recruited as the control group. The levels of PPARγ mRNA, serum ADP and lipids were compared between the groups. Receiver operating characteristic (ROC) curve analysis was undertaken to determine if the PPARγ mRNA level could be used as a predictive biomarker of CAL prognosis. Results The study enrolled 42 patients with KD (18 with CAL [CAL group] and 24 without CAL [NCAL group]) and 20 age-matched controls. PPARγ mRNA levels in patients with KD were significantly higher than those in the controls; but significantly lower in the CAL group than the NCAL group. ROC curve analysis demonstrated that the PPARγ mRNA level provided good predictive accuracy for the prognosis of CAL. There was no association between PPARγ, ADP and lipid levels. Conclusion There was dyslipidaemia in children with KD, but there was no correlation with PPARγ and ADP. PPARγ may be a predictor of CAL in patients with KD with good predictive accuracy.

A lignocellulosic residue, rice straw, was hydrothermally pretreated for the whole slurry anaerobic digestion. In contrast to the unpretreated rice straw, 110–120 °C pretreatment promoted biogas yield by 35%–38%, while only 14% promotion happened on the pretreatment at 180 °C. To understand why this improvement happened at lower severities, the pretreated rice straw at 90 °C, 120 °C, and 180 °C were selected for the further investigation, in which the liquor and solid fraction were separated for digestion, and compared with the whole slurry digestion. Results indicated more methane was released from the derived liquor of 180 °C than that of 90 °C and 120 °C, however, solid fraction did not exhibit significantly different methane yields (187.77–193.91 mL/g TS). These results suggested that the released soluble fraction from pretreatment could facilitate the methanogenesis. Furthermore, the released inherent soluble fraction in rice straw was mainly responsible for higher biogas yield at lower temperatures. Pretreatment at higher temperatures disintegrated the rice straw recalcitrance more, and intensified the release of soluble fraction accordingly. Consequently, the methanogenesis of whole slurry could be promoted at the initial digestion; the hydrolysis/acidification of the solid fraction in whole slurry was weakened greatly, which resulted in a lower biogas yield. This can also be proved by the evolution of dominant bacteria and archaea in the anaerobic digestion of whole slurry, separated solid and liquor fraction.

Composting leachate, a potential precursor, was attempted to prepare the activated carbons via hydrothermal carbonization plus KOH activation in this work. The obtained carbons were further investigated to check their electrochemical performances as electrode materials of supercapacitor. The carbon material that activated at 700 °C (CL-700) exhibits the highest specific surface area of 2184.9 m2 g−1 and the largest pore volume of 1.55 cm3 g−1 comparing to the activated carbons at other temperatures. In a three-electrode system, CL-700 displayed an excellent capacitance of 228 F g−1 at 0. 5 A g−1, and it was 178 F g−1 even though at a higher current density of 10 A g−1. After 5000 tests on the charge-discharge cycle, CL-700 showed a superior stability with 83.2% capacity retention and almost 100% coulombic efficiency at 5 A g−1. Moreover, CL-700 had a good energy density of 7.1 Wh kg−1 at a power density of 124.9 W kg−1 in a symmetric two-electrode system. Based on the comparison with the currently reported biomass-deriver carbons, the composting leachate can be regarded as a feasible precursor to harvest carbon materials for supercapacitor electrode, which was meaningful to offer a novel path for the valorization of the leachate fraction from bio-wastes.

Additional file 1. Search strategy, The search strategy in PubMed, EMBASE and Cochrane Library.

Pretreating lignocellulosic biomass by phosphoric acid plus hydrogen peroxide (PHP) was integrated with recovering concentrated phosphoric acid (CPA), lignin, and treating phosphorus (P) wastewater. Results indicated no significant effects on cellulose recovery was observed by promoting ethanol addition, but CPA and lignin recovery were improved to 80.0% and 23.3%, respectively. Increasing water addition did not greatly affect CPA recovery (80.0–80.4%), and lignin recovery (22.8–23.6%). Consequently, the ratio of 11:1 (ethanol/PHP solution) and 4:1 (water/de-ethanol liquor) were suggested for solid/liquid separation and lignin precipitation. Average 86.0% CPA was recycled for pretreatment (≥11 runs) with average 96.3% cellulose-glucose conversion. A specially-developed biochar from crab shell was efficient on P removal with maximal adsorption capacity of 261.6 mg/g. Pretreating 1.0 kg wheat straw by 1.1 kg CPA harvested 155.0 g ethanol, 45.0 g high purity lignin and 4.9 kg P-rich biochar fertilizer. Recovering CPA, biochar-fertilizer and lignin, and P wastewater treatment made PHP pretreatment towards more sustainable and cleaner.

In order to elucidate the possibility of applying biomass densification in anaerobic digestion, pelleting and briquetting were typically investigated for biogas production, and the anaerobic digestion using densified biomass at higher solid content was discussed as well. In addition, the logistic cost, including harvest, transportation, and storage, was also evaluated to check the economic feasibility once biomass densification was employed for biogas production. The results demonstrated that the main composition, including cellulose, hemicellulose and lignin, of the pelleted and briquetted corn stover exhibited some degradation compared with their corresponding undensified corn stover. Both pellets and briquettes had no adverse impacts on anaerobic digestion. The cumulative biogas production from pellets was 349.9 mL g−1 VS (VS: volatile solid), which was 25.8% higher than unpelleted corn stover (278.1 mL g−1 VS, respectively), moreover, the cumulative CH4 production from pellets was 185.7 mL g−1 VS compared with 135.1 mL g−1 VS of unpelleted corn stover. Biogas production from briquettes was also slightly higher than that of the unbriquetted corn stover, however, improvement was not statistically significant. Increasing the organic loading, relatively higher biogas and CH4 production can be achieved from briquettes compared with the unbriquetted corn stover. This was mainly attributed to more free water in the anaerobic digestion of briquettes. Especially, there was 11.7% improvement on biogas production as the organic loading was increased to 80 g TS per kg (TS: total solid). As the briquettes were employed for biogas production with the digestor scale of 3000 m3, the logistic cost could be curtailed by 36.1%. Evidently, the biomass densification can be employed in anaerobic digestion for biogas production to potentially solve the extra high cost of logistic issues.

Luffa was evaluated as a potential energy crop. A considerable amount of luffa sponge biomass can be grown in a vertical direction with approximately 70% polysaccharide content and low lignin content. When concentrated H3PO4 was employed to pretreat luffa sponge, hemicelluloses were the most sensitive component, followed by cellulose and lignin. Hemicellulose solubilization and cellulose loss positively responded to the elevated temperature, time, H3PO4 concentration, and dosage for pretreatment. However, lignin solubilization was not affected greatly. Although the initial hydrolysis rate was accelerated by increasing pretreatment temperature, the final glucose conversion was reduced as temperature was raised higher than 50 °C. Prolonging pretreatment time was positively correlated to enzymatic digestibility. When H3PO4 concentration was lower than 80%, the final glucose conversion was increased with increasing H3PO4 concentration. Increasing H3PO4 concentration to 84% for pretreatment caused the final glucose conversion to decrease slightly, although the hydrolysis rate was initially accelerated. Additionally, an improvement of glucose conversion was obtained with increasing the substrate-to-phosphoric acid ratio. However, the improvement was not cost-effective, as the ratio was lower than 1-to-8.