Cellulase production and efficient saccharification of biomass by a new mutant Trichoderma afroharzianum MEA-12.

BACKGROUND: Cellulase plays a key role in converting cellulosic biomass into fermentable sugar to produce chemicals and fuels, which is generally produced by filamentous fungi. However, most of the filamentous fungi obtained by natural breeding have low secretory capacity in cellulase production, which are far from meeting the requirements of industrial production. Random mutagenesis combined with adaptive laboratory evolution (ALE) strategy is an effective method to increase the production of fungal enzymes. RESULTS: This study obtained a mutant of Trichoderma afroharzianum by exposures to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), Ethyl Methanesulfonate (EMS), Atmospheric and Room Temperature Plasma (ARTP) and ALE with high sugar stress. The T. afroharzianum mutant MEA-12 produced 0.60, 5.47, 0.31 and 2.17 IU/mL FPase, CMCase, pNPCase and pNPGase, respectively. These levels were 4.33, 6.37, 4.92 and 4.15 times higher than those of the parental strain, respectively. Also, it was found that T. afroharzianum had the same carbon catabolite repression (CCR) effect as other Trichoderma in liquid submerged fermentation. In contrast, the mutant MEA-12 can tolerate the inhibition of glucose (up to 20 mM) without affecting enzyme production under inducing conditions. Interestingly, crude enzyme from MEA-12 showed high enzymatic hydrolysis efficiency against three different biomasses (cornstalk, bamboo and reed), when combined with cellulase from T. reesei Rut-C30. In addition, the factors that improved cellulase production by MEA-12 were clarified. CONCLUSIONS: Overall, compound mutagenesis combined with ALE effectively increased the production of fungal cellulase. A super-producing mutant MEA-12 was obtained, and its cellulase could hydrolyze common biomasses efficiently, in combination with enzymes derived from model strain T. reesei, which provides a new choice for processing of bioresources in the future.

Interleukin-10 polymorphisms (rs1800871, rs1800872 and rs1800896) and periodontitis risk: A meta-analysis.

OBJECTIVE: The objective of this meta-analysis was to assess the association between three interleukin-10 (IL-10) promoter single nucleotide polymorphisms (rs1800871, rs1800872, and rs1800896) and periodontitis risk. METHODS: A systematic search was conducted in PubMed, Embase, and China National Knowledge Infrastructure databases and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. RESULTS: Twenty-six studies met the inclusion criteria. The pooled analysis showed that rs1800871 was associated with an increased periodontitis risk under dominant model (CT + TT vs. CC: p = 0.004, OR = 1.79, 95% CI: 1.21-2.65) in Latin American populations but not in Asian (CT + TT vs. CC: p = 0.229, OR = 0.81, 95% CI: 0.58-1.14) and Caucasian (CT + TT vs. CC: p = 0.910, OR = 1.02, 95% CI: 0.75-1.39) populations. Similarly, rs1800872 conferred an increased risk of periodontitis only in Latin American populations (CA + AA vs. CC: p = 0.012, OR = 2.32, 95% CI: 1.20-4.47; A allele vs. C allele: p = 0.001, OR = 1.61, 95% CI: 1.22-2.14). No significant association was observed between rs1800896 and periodontitis risk. Subgrouping data according to periodontitis type revealed that rs1800872 was associated with both chronic periodontitis (A allele vs. C allele: p = 0.011, OR = 1.72, 95% CI: 1.13-2.62) and aggressive periodontitis (A allele vs. C allele: p = 0.038, OR = 1.32, 95% CI: 1.02-1.72). CONCLUSION: The studies reviewed support that the IL-10 rs1800871 and rs1800872 polymorphisms may represent a potential genetic biomarker for periodontitis risk in Latin American populations.

[Expression of STAT3 in alveolar bone during orthodontic tooth movement in rats].

PURPOSE: To study the changes of expression of signal transducer and activator of transcription 3 (STAT3) during orthodontic tooth movement (OTM). METHODS: Twenty six-week-old SD rats were selected, the upper left first molars were moved by coil spring and lasted for 7 days. The maxillary tissues were obtained at 0, 1, 3, 7 d and subjected to histological study. Statistical analysis was performed using SPSS 16.0 software package. RESULTS: The main changes in alveolar bone during orthodontic tooth movement included significant increase in osteoblast number and bone formation in the tension area, and bone resorption in the pressure area. The positive cells of osteocalcin in the tension area increased during OTM. The expression of STAT3 increased in the tension area at 3 d and 7 d in comparison with that at 0 d. CONCLUSIONS: Orthodontic force can stimulate alveolar bone remolding. The expression of STAT3 in the tension area may have effects on alveolar bone remolding during orthodontic tooth movement.

[Methodological and reporting quality assessment for Chinese systematic reviews and meta analysis in oral medicine].

PURPOSE: To evaluate the methodology and reporting quality of Chinese systematic reviews and meta analysis in oral medicine. METHODS: Chinese literatures of systematic reviews and meta analysis in oral medicine were searched in the CBM, VIP, WANFANG Database and CNKI from the establishment date to August 30, 2014. Two researchers screened and evaluated the data independently, and disagreements were resolved by discussion. Methodology and reporting quality of included literatures were evaluated by AMSTAR and PRISMA scale. RESULTS: Of the 204 literatures included in the analysis, the highest and lowest scores of methodology quality were 9 and 0, respectively. The average score was 4.95 ± 2.45. The main problems were insufficient in literature searching, absence of a list of included and excluded studies, lack of assessment for publication bias, etc. The highest and lowest scores of reporting quality were 21 and 4, and the average score of reporting quality was 14.07 ± 3.62. The main problems were incomplete report in abstract, data collection and analysis methods, bias control, conclusion, etc. CONCLUSIONS: The methodological qualities of Chinese systematic reviews and meta analysis in oral medicine are generally low, and their reporting qualities are also needed to be improved.

C60 fullerenol as an active and stable catalyst for the synthesis of cyclic carbonates from CO2 and epoxides.

C60 fullerenol was found to be a highly active, selective and stable catalyst for cycloaddition between CO2 and epoxides to produce various cyclic carbonates with excellent yields (89-99%). A solid/liquid interfacial hydrogen-bond assisted mechanism was proposed to account for its high efficiency.

[Effects of Radix Salviae Miltiorrhizae on Ca2+ in hepatic stellate cells].

OBJECTIVE: To investigate the effects of Radix Salviae Miltiorrhizae (RSM) on intracellular free calcium in hepatic stellate cells (HSCs). METHODS: After the model of hepatic fibrosis was established in SD rats, RSM [20 ml/(kg x d)] was given via gastrogavage to the rats of treatment groups while the same volume of 0.9% NaCl was given to the rats of control groups twice a day for 6 consecutive days. Then the blood sample was drawn from the inferior vena cava, and the serum was extracted for pharmacological studies. After 24 h incubation with 10% drug serum, HSCs were loaded with Fluo-3/AM, a Ca2+ marker, and were observed with laser scanning confocal microscopy (LSCM). RESULTS: By comparison with controls, both RSM pharmacological serums decreased [Ca2+]i in HSCs significantly in the condition of using Ang II or not (P<0.05). CONCLUSION: RSM decreased [Ca2+]i in activated HSCs, which may be one of important ways to block liver fibrosis.