A New Method for Solid Acid Catalyst Evaluation for Cellulose Hydrolysis

A systematic and structure-agnostic method for identifying heterogeneous activity of solid acids for catalyzing cellulose hydrolysis is presented. The basis of the method is preparation of a supernatant liquid by exposing the solid acid to reaction conditions and subsequent use of the supernatant liquid as a cellulose hydrolysis catalyst to determine the effects of in situ generated homogeneous acid species. The method was applied to representative solid acid catalysts, including polymer-based, carbonaceous, inorganic, and bifunctional materials. In all cases, supernatant liquids produced from these catalysts exhibited catalytic activity for cellulose hydrolysis. Direct comparison of the activity of the solid acid catalysts and their supernatants could not provide unambiguous detection of heterogeneous catalysis. A reaction pathway kinetic model was used to evaluate potential false-negative interpretation of the supernatant liquid test and to differentiate heterogeneous from homogeneous effects on cellulose hydrolysis. Lastly, differences in the supernatant liquids obtained in the presence and absence of cellulose were evaluated to understand possibility of false-positive interpretation, using structural evidence from the used catalysts to gain a fresh understanding of reactant–catalyst interactions. While many solid acid catalysts have been proposed for cellulose hydrolysis, to our knowledge, this is the first effort to attempt to differentiate the effects of heterogeneous and homogeneous activities. The resulting supernatant liquid method should be used in all future attempts to design and develop solid acids for cellulose hydrolysis.

A Potential Fungal Probiotic Aureobasidium melanogenum CK-CsC for the Western Honey Bee, Apis mellifera

Aureobasidium melanogenum has been used as an animal feed additive for improving the health of pets, however, it has not yet been applied in honey bees. Here, a fungal strain CK-CsC isolated from bee bread pollen, was identified as A. melanogenum. Following characterizing CK-CsC fermentation broth, the 4-days fermentation broth (SYM medium or bee pollen) of the CK-CsC was used to feed newly emerged adult honey bees in cages under laboratory-controlled conditions for analysis of survival, gene expression of nutrient and antibacterial peptide, and gut microbiota of honey bees. It was found that the CK–CsC fermentation broth (SYM medium or bee pollen) is nontoxic to honey bees, and can regularly increase nutrient gene expression of honey bees. However, significant mortality of bees was observed after bees were fed on the supernatant liquid of the fermentation broth. Notably, this mortality can be lowered by the simultaneous consumption of bee pollen. The honey bees that were fed bee pollen exhibited more γ-Proteobacteria, Bacteriodetes, and Actinobacteria in their gut flora than did the honey bees fed only crude supernatant liquid extract. These findings indicate that A. melanogenum CK–CsC has high potential as a bee probiotic when it was fermented with bee pollen.

THE SECOND-GENERATION PLATELET CONCENTRATES IN THE TREATMENT OF CHRONIC OSTEOMYELITIS: ONE MODERN REGENERATIVE SURGERY

Background: Hypothesis is that the use of fibrin rich in leukocytes and platelets advanced (A-PRF) in ulcer osteomyelitis on diabetic foot, allows recovery from this serious disease. In this study, the goal was to standardize the use of PRF in patients with osteomyelitis, to use this second-generation platelet concentrate, as a facilitator of healing. Methods: Authors produced and used peripheral blood A-PRF (1300 g × 8 min) membranes in 7 patients (all diabetic) with osteomyelitis and skin lesions for at least 6 months. Membranes, together with the supernatant liquid derived from compression, were inserted into the skin lesion down to the bone after surgical debridement. Evolution of the lesions over time was analyzed. Results: All seven patients had a positive Probe-to-Bone test, MRI detected cortico-periosteal thickening and/or foci of cortico-cancellous osteolysis adjacent to the ulcer. Gram-positive bacteria were found in our patients in 52% of cases. Cocci Gram +, such as S. Aureus (15.6%), S. -haemolytic (12.1%), S. Viridans (7.1%), and Bacilli Gram- such as Pseudomonas (10.6%), Proteus (7.8%), Enterobacter (5.7%) are present. Candida Albicans is present in 2.8%. Blood count showed no major changes. To date, skin lesions have healed in 6 of the seven patients treated (one patient for more than five years) with no signs of infection or recurrence. Conclusions: Results obtained on our patients suggest that PRF membranes may be a therapeutic option in this difficult to treat pathology.

Photoinhibition of Streptococcus mutans Biofilm-Induced Lesions in Human Dentin by Violet-Blue Light

This in vitro study determined the effectiveness of violet-blue light on Streptococcus mutans (UA159) biofilm induced dentinal lesions. Biofilm was formed on human dentin specimens in a 96-well microtiter plate and incubated for 13 h in the presence of tryptic soy broth (TSB) or TSB supplemented with 1% sucrose (TSBS). Violet-blue light (405 nm) from quantitative light-induced fluorescence (QLFTM) was used to irradiate the biofilm. Supernatant liquid was removed, and the biofilm was irradiated continuously with QLF for 5 min twice daily with an interval of 6 h for 5 d, except with one treatment on the final day. Colony forming units (CFU) of the treated biofilm, changes in fluorescence (∆F; QLF-Digital BiluminatorTM), lesion depth (L), and integrated mineral loss (∆Z; both transverse microradiography) were quantified at the end of the fifth day. Statistical analysis used analysis of variance (ANOVA), testing at a 5% significance level. In the violet-blue light irradiated groups, there was a significant reduction (p < 0.05) of bacterial viability (CFU) of S. mutans with TSB and TSBS. Violet-blue light irradiation resulted in the reduction of ∆F and L of the dentinal surface with TSBS. These results indicate that violet-blue light has the capacity to reduce S. mutans cell numbers.

The Toxic Effect of Herbicidal Ionic Liquids on Biogas-Producing Microbial Community

The aim of the study was to evaluate the effect of herbicidal ionic liquids on the population changes of microorganisms used in a batch anaerobic digester. The influence of the following ionic liquids: benzalkonium (2,4-dichlorophenoxy)acetate (BA)(2,4-D), benzalkonium (4-chloro-2-methylphenoxy)acetate (BA)(MCPA), didecyldimethylammonium (2,4-dichlorophenoxy)acetate (DDA)(2,4-D), didecyldimethylammonium (4-chloro-2-methylphenoxy)acetate (DDA)(MCPA), as well as reference herbicides (4-chloro-2-methylphenoxy)acetic acid (MCPA) and (2,4-dichlorophenoxy)acetic acid (2,4-D) in the form of sodium salts on biogas production efficiency was investigated. The effective concentration (EC50) values were determined for all tested compounds. (MCPA)− was the most toxic, with an EC50 value of 38.6–41.2 mg/L. The EC50 for 2,4-D was 55.7–59.8 mg/L. The addition of the test substances resulted in changes of the population structure of the microbiota which formed the fermentation pulp. The research was based on 16S rDNA analysis with the use of the Next Generation Sequencing method and the MiSeq platform (Illumina, San Diego, CA, USA). There was a significant decrease in bacteria belonging to Firmicutes and Archaea belonging to Euryarchaeota. A significant decrease of the biodiversity of the methane fermentation microbiota was also established, which was expressed by the decrease of the operational taxonomic units (OTUs) and the value of Shannon’s entropy. In order to determine the functional potential of bacterial metapopulations based on the 16SrDNAprofile, the PICRUSt(Phylogenetic Investigation of Communities by Reconstruction of Unobserved States)tool was used, which allowed to determine the gene potency of microorganisms and their ability to biodegrade the herbicides. In the framework of the conducted analysis, no key genes related to the biodegradation of MCPA or 2,4-D were found, and the observed decrease of their content in the supernatant liquid was caused by their sorption on bacterial biomass.

VARIABILITY OF SELECTED PARAMETERS AS A RESULT OF MICROWAVE DISINTEGRATION OF SEWAGE SLUDGE

This article contains the results of investigations conducted at the WULS in Warsaw concerning initial treatment of sewage sludge by means of microwave disintegration. Sewage sludge were taken from the "Mokre Łąki" wastewater treatment plant in the municipality of Izabelin. Experiments were carried out on concentrated and non-concentrated sludge. Each of the sludges was disintegrated in portions of varying volumes and also at different time of microwave interactions. Significant changes in the values of the tested parameters such as COD, turbidity and temperature due to the sludge suppression process were considered. These parameters have a significant impact on the course of further processes that treated sludge and supernatant liquid can be processed. Therefore, determining the volatility of these parameters is important.

Self-Stabilized Precipitation Polymerization and Its Application

An effective, value-added use of the large amounts of olefinic compounds produced in the processing of petroleum, aside from ethylene and propylene, has been a long outstanding challenge. Here, we developed a novel heterogeneous polymerization method, beyond emulsion/dispersion/suspension, termed self-stabilized precipitation (2SP) polymerization, which involves the nucleation and growth of nanoparticles (NPs) of a well-defined size without the use of any stabilizers and multifunctional monomers (crosslinker). This technique leads to two revolutionary advances: (1) the generation of functional copolymer particles from single olefinic monomer or complex olefinic mixtures (including C4/C5/C9 fractions) in large quantities, which open a new way to transform huge amount of unused olefinic compounds in C4/C5/C9 fractions into valuable copolymers, and (2) the resultant polymeric NPs possess a self-limiting size and narrow size distribution, therefore being one of the most simple, efficient, and green strategies to produce uniform, size-tunable, and functional polymeric nanoparticles. More importantly, the separation of the NPs from the reaction medium is simple and the supernatant liquid can be reused; hence this new synthetic strategy has great potential for industrial production.

Aktivitas antibakteri ekstrak etanolik kulit batang jambu mete (Anacardium occidentale Linn.) terhadap Staphylococcus aureus

Antibacterial activity of cashew stembark (Anacardium occidentale Linn) on Staphylococcus aureus. Microbial activity acts as a sign of disruption of bacterial growth. The bark of cashew (Anacardium occidentale Linn.) contains phenolic compounds such as flavonoids, tannins and anacardic acid which have an activity as antimicrobial. One of the Gram positivebacteria in the oral cavity was Staphylococcus aureus (S. aureus). The aim of the study was to observe the bacterial activity of ethanolic extract of the cashew to a metal ion, i.e. Ca2+ and K+ leakage from S aureus. This research used one ose bacteria S. aureus at a density of 106 standard Brown as much as 10 mL and centrifuged at a speed of 3500 rpm for 20 minutes. The filtrate discarded, pellets in the tube was washed using phosphate buffer pH 7.0. Furthermore the ethanolic extract of the bark of the cashew stembark was added in the concentrations of 3.5% and 7% without any extract as a control, each of which was in 5 tubes, incubated in an incubator for 24 hours. The suspension was centrifused with a speed of 3500 rpm for 20 minutes prior to be filtered. Supernatant liquid was taken and measured absorbance using AAS. Data were analyzed using one way Anova p = 0.05. The results showed that leakage of Ca2+ was at concentrations of 0%, 3%, 5% and 7% were 2.42 ± 0.82; 32.87 ± 1.97; 49.10 ± 3.33; 66.73 ± 3.29, respectively while for the K+ metal was 15.28 ± 0.46; 606.36 ± 14.14; 895 ± 9.5; 1251 ± 11.54. Anova one way showed a significant effect (p <0.050) ethanolic extract of the bark of cashew against leakage of metal ions Ca2+ and K+ at S aureus bacteria. LSD test showed a significant difference among all treatment groups. It was concluded that there was antibacterial activity of ethanolic extract of the cashew stembark on bacteria S. aureus based on leakage of metal ions Ca2+ and K+ The highest leakage of metal ions was at the concentrations of 7%. ABSTRAKAktivitas antibakteri merupakan tanda terganggunya pertumbuhan bakteri. Kulit batang tanaman jambu mete (Anacardium occidentale Linn.) mengandung senyawa fenolik seperti flavonoid dan tanin serta asam anakardat yang memiliki aktivitas sebagai antibakteri. Salah satu bakteri gram positif dalam mulut yang patogen adalah Staphylococcus aureus (S.aureus). Penelitian ini bertujuan untuk mengetahui aktivitas antibakteri kulit batang jambu mete (anacardium occidentale Linn.) terhadap S.aureus yang ditandai dengan kebocoran ion logam. Penelitian menggunakan sebanyak 1 ose dengan kepadatan 106 CFL/mL disentrifuse dengan kecepatan 3500 rpm selama 20 menit. Filtrat dibuang, pellet dalam tabung dicuci menggunakan buffer fosfat pH 7,0. Ekstrak etanolik kulit batang jambu mete konsentrasi 3; 5 dan 7% serta tanpa ekstrak sebagai kontrol, masing-masing dalam 5 tabung, diinkubasi dalam inkubator goyang selama 24 jam. Suspensi kemudian disentrifuse dengan kecepatan 3500 rpm selama 20 menit lalu disaring. Cairan supernatan diambil diukur absorbansinya menggunakan AAS (Atomic absorption Spectroscopy). Data dianalisis menggunakan Anava satu jalur. Hasil menunjukkan kebocoran Ca2+ pada konsentrasi 0, 3, 5 dan 7% berturut-turut adalah 2,42 ± 0,82; 32,87 ± 1,97; 49,10 ± 3,3; 66,73 ± 3,29, sedangkan logam K+ adalah 15,28 ± 0,46; 606,36 ± 14,14; 895 ± 9,5; 1251 ± 11,54. Hasil analisis statistik Anava menunjukkan terdapat aktivitas antibakteri ekstrak etanolik kulit batang jambu mete. Hasil LSD menunjukkan terdapat perbedaan yang bermakna antar seluruh kelompok perlakuan. Kesimpulan terdapat aktivitas antibakteri ekstrak etanolik kulit batang jambu mete terhadap S.aureus dilihat dari kebocoran ion logam Ca2+ and K+. Kebocoran tertinggi pada konsentrasi ekstrak 7%.