Wuliangye strong aroma baijiu promotes intestinal homeostasis by improving gut microbiota and regulating intestinal stem cell proliferation and differentiation.

BACKGROUND: Wuliangye strong aroma baijiu (hereafter, Wuliangye baijiu) is a traditional Chinese grain liquor containing short-chain fatty acids, ethyl caproate, ethyl lactate, other trace components, and a large proportion of ethanol. The effects of Wuliangye baijiu on intestinal stem cells and intestinal epithelial development have not been elucidated. Here, the role of Wuliangye baijiu in intestinal epithelial regeneration and gut microbiota modulation was investigated by administering a Lieber-DeCarli chronic ethanol liquid diet in a mouse model to mimic long-term (8 weeks') light/moderate alcohol consumption (1.6 g kg-1 day-1) in healthy human adults. RESULTS: Wuliangye baijiu promoted colonic crypt proliferation in mice. According to immunofluorescence and reverse transcription-quantitative polymerase chain reaction analyses, compared with the ethanol-only treatment, Wuliangye baijiu increased the number of intestinal stem cells and goblet cells and the expression of enteroendocrine cell differentiation markers in the mouse colon. Furthermore, gut microbiota analysis showed an increase in the relative abundance of microbiota related to intestinal homeostasis following Wuliangye baijiu administration. Notably, increased abundance of Bacteroidota, Faecalibaculum, Lachnospiraceae, and Blautia may play an essential role in promoting stem-cell-mediated intestinal epithelial development and maintaining intestinal homeostasis. CONCLUSIONS: In summary, these findings suggest that Wuliangye baijiu can be used to regulate intestinal stem cell proliferation and differentiation in mice and to alter gut microbiota distributions, thereby promoting intestinal homeostasis. This research elucidates the mechanism by which Wuliangye baijiu promotes intestinal health. © 2024 Society of Chemical Industry.

Systolic heart failure induced by butylparaben in zebrafish is caused through oxidative stress and immunosuppression.

Due to Butylparaben (BuP) widespread application in cosmetics, food, pharmaceuticals, and its presence as an environmental residue, human and animal exposure to BuP is common, potentially posing hazards to both human and animal health. Congenital heart disease is already a serious problem. However, the effects of BuP on the developing heart and its underlying mechanisms remain unclear. Here, zebrafish embryos were exposed to environmentally and human-relevant concentrations of BuP (0.6 mg/L, 1.2 mg/L, and 1.8 mg/L, calculated but not measured) at 6 h post-fertilization (hpf) and were treated until 72 hpf. Exposure to BuP led to cardiac morphological defects and cardiac dysfunction in zebrafish embryos, manifesting symptoms similar to systolic heart failure. The etiology of BuP-induced systolic heart failure in zebrafish embryos is multifactorial, including cardiomyocyte apoptosis, endocardial and atrioventricular valve damage, insufficient myocardial energy, impaired Ca2+ homeostasis, depletion of cardiac-resident macrophages, cardiac immune non-responsiveness, and cardiac oxidative stress. However, excessive accumulation of reactive oxygen species (ROS) in the cardiac region and cardiac immunosuppression (depletion of cardiac-resident macrophages and cardiac immune non-responsiveness) may be the predominant factors. In conclusion, this study indicates that BuP is a potential hazardous substance that can cause adverse effects on the developing heart and provides evidence and insights into the pathological mechanisms by which BuP leads to cardiac dysfunction. It may help to prevent the BuP-based congenital heart disease heart failure in human through ameliorating strategies and BuP discharge policies, while raising awareness to prevent the misuse of preservatives.

Microalgal flocculation: Global research progress and prospects for algal biorefinery.

Microalgal research has made significant progress due to versatile and high-value industrial applications of microalgal biomass or its derivatives. However, to explore their full potential and to achieve commercial robustness, microalgal biorefinery needs cost-effective technologies to produce, harvest, and process the microalgal biomass on large scale as higher production and harvesting cost is one of the key hindrances in the commercialization of algae-based products. Among several other algal biomass harvesting technologies, self-flocculation seems to be an attractive, low-cost, and eco-friendly harvesting technology. This review covers various flocculation-based methods that have been employed to harvest microalgal biomass with a special emphasis on self-flocculation in microalgae. Moreover, genetic engineering approaches to induce self-flocculation in non-flocculating microalgae along with the factors affecting self-flocculation and recent research trends have also been discussed. It is concluded that self-flocculation is the most desired approach for the energy- and environment-efficient harvesting of microalgal biomass. However, its poorly understood genetic basis needs to be deciphered through detailed studies to harness its potential for the algal biorefinery.

Engineering the metabolic pathways of lipid biosynthesis to develop robust microalgal strains for biodiesel production.

Algal lipids have shown promising feedstock to produce biodiesel due to higher energy content, higher cetane number, and renewable nature. However, at present, the lipid productivity is too low to meet the commercial needs. Various approaches can be employed to enhance the lipid content and lipid productivity in microalgae. Stress manipulation is an attractive option to modify the algal lipid content, but it faces the drawback of time-consuming production processing and lack of information about molecular mechanisms related to triacylglycerides production in response to stress. Developing the robust hyper lipid accumulating algal strains has gained momentum due to advances in metabolic engineering and synthetic biology tools. Understanding the molecular basis of lipid biosynthesis followed by reorienting the related pathways through genomic modification is an alluring strategy that is believed to achieve the industrial and economic robustness. This review portrays the use of integrated OMIC approaches to elucidate the molecular mechanisms of strain adaptability in response to stress conditions, and identification of molecular pathways that should become novel targets to develop novel algal strains. Moreover, an update on the metabolic engineering approaches to improve the lipid production in microalgae is also provided.

Bacillus licheniformis-based intensive fermentation of Tibetan tea improved its bioactive compounds and reinforced the intestinal barrier in mice.

Tibetan tea changes during microorganism fermentation. Research on microorganisms in Tibetan tea has focused on their identification, while studies on the influence of specific microorganisms on the components and health functions of Tibetan tea are lacking. Bacillus licheniformis was inoculated into Tibetan tea for intensive fermentation, and the components of B. licheniformis-fermented tea (BLT) were detected by liquid chromatography with tandem mass spectrometry (UHPLC-TOF-MS), and then the effects of BLT on intestinal probiotic functions were investigated by experiments on mice. The results revealed the metabolites of BLT include polyphenols, alkaloids, terpenoids, amino acids, and lipids. Intensified fermentation also improved the antioxidant capacity in vivo and the protective effect on the intestinal barrier of Tibetan tea. In addition, the enhanced fermentation of Tibetan tea exerted intestinal probiotic effects by modulating the relative abundance of short-chain fatty acid-producing bacteria in the intestinal flora. Therefore, intensive fermentation with B. licheniformis can improve the health benefits of Tibetan tea.

Microalgae growth-promoting bacteria for cultivation strategies: Recent updates and progress.

Microalgae growth-promoting bacteria (MGPB), both actinobacteria and non-actinobacteria, have received considerable attention recently because of their potential to develop microalgae-bacteria co-culture strategies for improved efficiency and sustainability of the water-energy-environment nexus. Owing to their diverse metabolic pathways and ability to adapt to diverse conditions, microalgal-MGPB co-cultures could be promising biological systems under uncertain environmental and nutrient conditions. This review proposes the recent updates and progress on MGPB for microalgae cultivation through co-culture strategies. Firstly, potential MGPB strains for microalgae cultivation are introduced. Following, microalgal-MGPB interaction mechanisms and applications of their co-cultures for biomass production and wastewater treatment are reviewed. Moreover, state-of-the-art studies on synthetic biology and metabolic network analysis, along with the challenges and prospects of opting these approaches for microalgal-MGPB co-cultures are presented. It is anticipated that these strategies may significantly improve the sustainability of microalgal-MGPB co-cultures for wastewater treatment, biomass valorization, and bioproducts synthesis in a circular bioeconomy paradigm.

A nature-based closed-loop wastewater treatment system at vehicle-washing facilities: From linear to circular economy.

Pakistan, among the top five most water-stressed nations globally, grapples with water scarcity owing to inadequate treatment infrastructure and groundwater overextraction. We demonstrate a successful nature-based closed-loop system to treat wastewater from urban vehicle-washing facilities, previously reliant on groundwater. An eco-friendly integrated system containing floating treatment wetlands (FTWs), subsurface flow constructed wetlands (SSF-CWs), and sand filtration (SF) was designed and installed at three vehicle-washing facilities for wastewater treatment and reuse in a loop. While the system is still operational after years, a consistent and significant reduction in water quality indicators is recorded, successfully meeting the national environmental quality standards of Pakistan. By reducing per unit water treatment costs to as low as $0.0163/m³ and achieving payback periods under a year, the embrace of these closed-loop strategies vividly underscores the imperative of transitioning to a circular economy in the domains of wastewater treatment and resource conservation.

A novel integrated approach employing Desertifilum tharense BERC-3 for efficient wastewater valorization and recycling for developing peri-urban algae farming system.

Peri-urban environments are significant reservoirs of wastewater, and releasing this untreated wastewater from these resources poses severe environmental and ecological threats. Wastewater mitigation through sustainable approaches is an emerging area of interest. Algae offers a promising strategy for carbon-neutral valorization and recycling of urban wastewater. Aiming to provide a proof-of-concept for complete valorization and recycling of urban wastewater in a peri-urban environment in a closed loop system, a newly isolated biocrust-forming cyanobacterium Desertifilum tharense BERC-3 was evaluated. Here, the highest growth and lipids productivity were achieved in urban wastewater compared to BG11 and synthetic wastewater. D. tharense BERC-3 showed 60-95% resource recovery efficiency and decreased total dissolved solids, chemical oxygen demand, biological oxygen demand, nitrate nitrogen, ammonia nitrogen and total phosphorus contents of the water by 60.37%, 81.11%, 82.75%, 87.91%, 85.13%, 85.41%, 95.87%, respectively, making it fit for agriculture as per WHO's safety limits. Soil supplementation with 2% wastewater-cultivated algae as a soil amender, along with its irrigation with post-treated wastewater, improved the nitrogen content and microbial activity of the soil by 0.3-2.0-fold and 0.5-fold, respectively. Besides, the availability of phosphorus was also improved by 1.66-fold. The complete bioprocessing pipeline offered a complete biomass utilization. This study demonstrated the first proof-of-concept of integrating resource recovery and resource recycling using cyanobacteria to develop a peri-urban algae farming system. This can lead to establishing wastewater-driven algae cultivation systems as novel enterprises for rural migrants moving to urban areas.

Increased importin 13 activity is associated with the pathogenesis of pterygium.

PURPOSE: We previously reported that importin 13 (IPO13), a member of the importin-ß family of nuclear import proteins, regulates nuclear import of the glucocorticoid receptor in airway epithelial cells, IPO13 serves as a potential marker for corneal epithelial progenitor cells, and IPO13 is associated with corneal cell proliferation. Here we investigated the role of IPO13 in the pathogenesis of pterygium and the underlying mechanism including interaction with other cell proliferation-related factors: keratin 17 (K17), a lesional protein and a member of the type I keratins, and c-Jun, a protein of the activator protein-1 complex. METHODS: Tissue samples were collected from primary pterygia, recurrent pterygia, and normal conjunctiva to perform the following experiments: immunohistochemical measurement of IPO13 and K17. Pterygium epithelial cells (PECs) were cultured in keratinocyte serum-free defined medium to examine the expression of IPO13 and K17. Lentivirus-mediated silencing and overexpression IPO13 testing was conducted, and K17 alternation was evaluated with western blot and immunostaining. In addition, the translocation of c-Jun (a K17 regulator) was further examined after IPO13 was silenced. RESULTS: IPO13 activity was significantly increased in the basal layer of the epithelium of the pterygium. In cultured PECs, overexpression or knockdown of the IPO13 gene increased or decreased PEC proliferation, respectively. IPO13 was colocalized with K17 in the epithelium of the pterygium, and overexpression or knockdown of the IPO13 gene induced upregulation or downregulation of K17 expression in PECs, respectively. In addition, silencing of the IPO13 gene blocked nuclear translocation of c-Jun. CONCLUSIONS: We provided novel evidence that IPO13 may contribute to the pathogenesis of pterygium via modulation of K17 and c-Jun.

Metabolomic Analysis of Fermented Tibetan Tea Using Bacillus circulans and Their Biological Activity on Mice via the Intestine-Hepatic Axis.

The use of Bacillus circulans as the sole starter provides better process control compared to natural fermentation. However, the chemical composition of fermented Tibetan tea by B. circulans and its regulatory effects on the intestine-liver axis has not been reported. For this purpose, a high-resolution liquid chromatography tandem mass spectrometry metabolomics approach was performed. The effects of fermented Tibetan tea on the intestine-liver axis of mice were also evaluated. Untargeted metabolomics analysis showed that the contents of catechin derivatives, flavonoids, phenolic acids, and terpenoids increased by 0.3, 2.38, 2.65, and 3.36%, respectively, compared with those before fermentation. Furthermore, 16S ribosomal RNA sequence analysis revealed that the relative abundance of Lactobacillus spp. in the intestine increased after consumption of fermented tea. Additionally, based on histological and quantitative PCR analyses, fermented Tibetan tea also improved intestinal development and intestinal barrier function in mouse, while increasing the antioxidant capacity of mouse liver. Thus, fermented Tibetan tea could provide beneficial health effects through the intestine-liver axis. These findings have facilitated the study of the chemical composition of Tibetan tea and provided theoretical support for its use as a natural beverage with intestinal probiotic functions.

Improved remediation of amoxicillin-contaminated water by floating treatment wetlands intensified with biochar, nutrients, aeration, and antibiotic-degrading bacteria.

Residual antibiotics have become emerging contaminants of concern for their adverse impact on the ecosystem. Additionally, their accumulation in the environment is increasing antibiotic resistance among pathogens. This study assessed the impact of intensification of biochar, nutrients, aeration, and bacteria (BNAB) on the remediation potential of floating treatment wetlands (FTWs) to treat amoxicillin (AMX)-contaminated water. The FTWs were developed with saplings of Vetiveria zizanioides and intensified with biochar (1.5%), nutrients (25 mgL-1 N, 25 mgL-1 P, 20 mg L1 K), aeration (7 mg L-1), and AMX-degrading bacteria. The results showed that all the amendments enhanced the AMX degradation, while the maximum reduction in COD (89%), BOD (88%), TOC (87%), and AMX (97%) was shown by the combined application of all the amendments. The combined application also enhanced plant growth and persistence of the inoculated bacteria in the water, roots, and shoots. This approach can be employed for the low-cost, environment-friendly treatment, and recycling of antibiotic-contaminated wastewater, where BNAB intensification can further improve the bioremediation efficiency of FTWs in the case of heavily polluted waters.

Vetiver grass floating treatment wetlands (FTWs) removed 83% amoxicillin.Intensification of floating treatment wetlands enhanced amoxicillin removal to 97%.Intensified-FTW removed COD, BOD, and TOC by 89%, 88%, and 87%, respectively.Potential of Intensified-FTW for bioremediation of highly polluted water is shown.

Targeted genome editing in polyploids: lessons from Brassica.

CRISPR-mediated genome editing has emerged as a powerful tool for creating targeted mutations in the genome for various applications, including studying gene functions, engineering resilience against biotic and abiotic stresses, and increasing yield and quality. However, its utilization is limited to model crops for which well-annotated genome sequences are available. Many crops of dietary and economic importance, such as wheat, cotton, rapeseed-mustard, and potato, are polyploids with complex genomes. Therefore, progress in these crops has been hampered due to genome complexity. Excellent work has been conducted on some species of Brassica for its improvement through genome editing. Although excellent work has been conducted on some species of Brassica for genome improvement through editing, work on polyploid crops, including U's triangle species, holds numerous implications for improving other polyploid crops. In this review, we summarize key examples from genome editing work done on Brassica and discuss important considerations for deploying CRISPR-mediated genome editing more efficiently in other polyploid crops for improvement.

In-silico annotation of the chemical composition of Tibetan tea and its mechanism on antioxidant and lipid-lowering in mice.

BACKGROUND/OBJECTIVES: Tibetan tea is a kind of dark tea, due to the inherent complexity of natural products, the chemical composition and beneficial effects of Tibetan tea are not fully understood. The objective of this study was to unravel the composition of Tibetan tea using knowledge-guided multilayer network (KGMN) techniques and explore its potential antioxidant and hypolipidemic mechanisms in mice. MATERIALS/METHODS: The C57BL/6J mice were continuously gavaged with Tibetan tea extract (T group), green tea extract (G group) and ddH2O (H group) for 15 days. The activity of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) in mice was detected. Transcriptome sequencing technology was used to investigate the molecular mechanisms underlying the antioxidant and lipid-lowering effects of Tibetan tea in mice. Furthermore, the expression levels of liver antioxidant and lipid metabolism related genes in various groups were detected by the real-time quantitative polymerase chain reaction (qPCR) method. RESULTS: The results showed that a total of 42 flavonoids are provisionally annotated in Tibetan tea using KGMN strategies. Tibetan tea significantly reduced body weight gain and increased T-AOC and SOD activities in mice compared with the H group. Based on the results of transcriptome and qPCR, it was confirmed that Tibetan tea could play a key role in antioxidant and lipid lowering by regulating oxidative stress and lipid metabolism related pathways such as insulin resistance, P53 signaling pathway, insulin signaling pathway, fatty acid elongation and fatty acid metabolism. CONCLUSIONS: This study was the first to use computational tools to deeply explore the composition of Tibetan tea and revealed its potential antioxidant and hypolipidemic mechanisms, and it provides new insights into the composition and bioactivity of Tibetan tea.

Effects of Pu-erh and Dian Hong tea polyphenols on the gut-liver axis in mice.

Tea polyphenols (TP) are the most biologically active components in tea, with antioxidant, antiobesity, and antitumor properties, as well as the ability to modulate the composition and function of intestinal microbiota. This experimental study evaluated the chemical constituents of polyphenols in Pu-erh (PTP) and Dian Hong tea (DHTP). It also investigated the co-regulatory effects of PTP and DHTP on intestinal flora and liver tissues in mice using 16 S rRNA gene and transcriptome sequencing. The results revealed that DHT had higher concentrations of EGC (epigallocatechin), C (catechin), EC (epicatechin), and EGCG (epigallocatechin gallate). In contrast, PT had higher concentrations of GA (gallic acid), ECG (epicatechin-3-gallate), TF (theaflavin), and TB (theabrownin). PTP and DHTP consumption significantly reduced the rates of weight gain in mice. Microbial community diversity was significantly higher in PTP and DHTP-treated mice than in the control group. Notably, beneficial microbes such as Lactobacillus increased significantly in PTP-treated mice, whereas Lachnospiraceae increased significantly in DHTP-treated mice. Both PTP and DHTP improved the activity of the antioxidant enzymes (SOD) and total antioxidant capacity (T-AOC) in the liver. The transcriptome analysis revealed that the beneficial effects of PTP and DHTP were due to changes in various metabolic pathways, the majority of which were related to antioxidant and lipid metabolism. This study discovered that PTP and DHTP had beneficial effects in mice via the gut-liver axis.

Prospects of algae-based green synthesis of nanoparticles for environmental applications.

Green synthesis of nanoparticles (NPs) has emerged as an eco-friendly alternative to produce nanomaterials with diverse physical, chemical, and biological characteristics. Previously used, physical and chemical methods involve the production of toxic byproducts, costly instrumentation, and energy-intensive experimental processes thereby, limiting their applicability. Biogenic synthesis of nanoparticles has come forward as a potential alternative, providing an eco-friendly, cost-effective, and energy-efficient approach for the synthesis of a diverse range of NPs. Several biological entities are employed in the biosynthesis of NPs including bacteria, fungi, and algae. However, the distinguishing characteristics of microalgae and cyanobacteria make them promising candidates for NPs synthesis because of their higher growth rate, substantially higher rate of sequestering CO2, hyperaccumulation of heavy metals, absence of toxic byproducts, minimum energy input, and employment of biomolecules (pigments and enzymes) as reducing and capping agents. Algal extract, being a natural reducing and capping agent, serves as a living cell factory for the efficient green synthesis of nanoparticles. Physiological and biological methods allow algal cells to uptake heavy metals and utilize them as nutrient source to generate biomass by regulating their metabolic processes. Despite their enormous potential, studies on the microalgae-based synthesis of nanoparticles for the removal of toxic pollutants from wastewater remained an unexplored research area in the literature. This review was aimed to summarize the recent advancements and prospects in the algae-based synthesis of nanoparticles for environmental applications particularly treating the wastewater.

Untargeted metabolomics of the alkaliphilic cyanobacterium Plectonema terebrans elucidated novel stress-responsive metabolic modulations.

Alkaliphilic cyanobacteria are suitable candidates to study the effect of alkaline wastewater cultivation on molecular metabolic responses. In the present study, the impact of wastewater, alkalinity, and alkaline wastewater cultivation was studied on the biomass production, biochemical composition, and the alkalinity responsive molecular mechanism through metabolomics. The results suggested a 1.29 to 1.44-fold higher biomass production along with improved lipid, carbohydrate, and pigment production under alkaline wastewater cultivation. The metabolomics analysis showed 1.2-fold and 5.54-fold increase in the indole-acetic acid and phytoene biosynthesis which contributed to overall enhanced cell differentiation and photo-protectiveness. Furthermore, lower levels of Ribulose-1,5-bisphosphate (RuBP), and higher levels of 2-phosphoglycerate and 3-phosphoglycerate suggested the efficient fixation of CO2 into biomass, and storage compounds including polysaccharides, lipids, and sterols. Interestingly, except L-histidine and L-phenylalanine, all the metabolites related to protein biosynthesis were downregulated in response to wastewater and alkaline wastewater cultivation. The cells protected themselves from alkalinity and nutrient stress by improving the biosynthesis of sterols, non-toxic antioxidants, and osmo-protectants. Alkaline wastewater cultivation regulated the activation of carbon concentration mechanism (CCM), glycolysis, fatty-acid biosynthesis, and shikimate pathway. The data revealed the importance of alkaline wastewater cultivation for improved CO2 fixation, wastewater treatment, and producing valuable bioproducts including phytoene, Lyso PC 18:0, and sterols. These metabolic pathways could be future targets of metabolic engineering for improving biomass and metabolite production. SIGNIFICANCE: Alkalinity is an imperative factor, responsible for the contamination control and biochemical regulation in cyanobactera, especially during the wastewater cultivation. Currently, understanding of alkaline wastewater responsive molecular mechanism is lacking and most of the studies are focused on transcriptomics of model organisms for this purpose. In this study, untargeted metabolomics was employed to analyze the impact of wastewater and alkaline wastewater on the growth, CO2 assimilation, nutrient uptake, and associated metabolic modulations of the alkaliphilic cyanobacterium Plectonema terebrans BERC10. Results unveiled that alkaline wastewater cultivation regulated the activation of carbon concentration mechanism (CCM), glycolysis, fatty-acid biosynthesis, and shikimate pathway. It indicated the feasibility of alkaline wastewater as promising low-cost media for cyanobacterium cultivation. The identified stress-responsive pathways could be future genetic targets for strain improvement.

Characterization of a newly isolated self-flocculating microalga Bracteacoccus pseudominor BERC09 and its evaluation as a candidate for a multiproduct algal biorefinery.

Microalgae have the highest capability to fix the atmospheric carbon and wastewater-derived nutrients to produce high-value bioproducts including lipids and carotenoids. However, their lower titers and single-product-oriented biomass processing have made the overall process expensive. Hence, increased metabolite titer and processing of the biomass for more than one product are required to ensure the commercial robustness of the algal biorefinery. In this study, a newly isolated algal strain was identified as Bracteacoccus pseudominor BERC09 through phylogenetic analysis based on the 18S rRNA gene sequence. Basic characterization of the strain revealed its promising potential to produce carotenoids and lipids. The lipids and carotenoid biosynthesis pathways of BERC09 were further triggered by manipulating the abiotic factors including nitrogen sources (NaNO3, KNO3, NH4Cl, Urea), nitrogen concentrations (0.06-0.36 gL-1), light intensity (150 µmolm-2s-1 to 300 µmolm-2s-1), and light quality (white and blue). Resultantly, 300 µmolm-2s-1 of blue light yielded 0.768 gL-1 of biomass, 8.4 mgg-1 of carotenoids, and 390 mgg-1 of lipids, and supplementation of 0.36 gL-1 of KNO3 further improved metabolism and yielded 0.814 gL-1 of biomass, 11.86 mgg-1 of carotenoids, and 424 mgg-1 of lipids. Overall, the optimal combination of light and nitrogen concurrently improved biomass, carotenoids, and lipids by 3.5-fold, 6-fold, and 4-fold than control, respectively. Besides, the excellent glycoproteins-based self-flocculation ability of the strain rendered an easier harvesting via gravity sedimentation. Hence, this biomass can be processed in a cascading fashion to use this strain as a candidate for a multiproduct biorefinery to achieve commercial robustness and environmental sustainability.

Molecular characterization of the modular chitin binding protein Cbp50 from Bacillus thuringiensis serovar konkukian.

Bacillus thuringiensis is an insecticidal bacterium whose chitinolytic system may be exploited to improve the insecticidal system of Bt-crops. A nucleotide fragment of 1368 bp from B. thuringiensis serovar konkukian S4, containing the complete coding sequence of the chitin binding protein Cbp50, was cloned and sequenced. Analyses have shown the protein to contain a modular structure consisting of an N-terminal CBM33 domain, two copies of a fibronectin-like domain and a C-terminal chitin binding domain classified as CBM5. The Cbp50 protein was heterologously expressed in Escherichia coli, purified and assessed for chitin binding activity. A deletion mutant (CBD-N; containing only the N-terminal CBM33 domain) of Cbp50 was produced to determine the role of C-terminal domains in the binding activity of the protein. The full-length Cbp50 was shown to bind ß-chitin most efficiently followed by α-chitin, colloidal chitin and cellulose. The polysaccharide binding activity of CBD-N was drastically decreased. The data demonstrate that both the N-terminal and C-terminal domains of Cbp50 are essential for the efficient binding of chitin. The purified Cbp50 showed antifungal activity against the phytopathogenic fungus Fusarium oxysporum and the opportunistic human pathogen Aspergillus niger. This is the first report of a modular chitin binding protein in bacteria.

Elucidating the pyrolysis reaction mechanism of Calotropis procera and analysis of pyrolysis products to evaluate its potential for bioenergy and chemicals.

The present study was focused on evaluating the bioenergy potential of waste biomass of desert plant Calotropis procera. The biomass was pyrolyzed at four heating rates including 10 °Cmin-1, 20 °Cmin-1, 40 °Cmin-1, and 80 °Cmin-1. The pyrolysis reaction kinetics and thermodynamics parameters were assessed using isoconversional models namely Kissenger-Akahira-Sunose, Flynn-Wall-Ozawa, and Starink. Major pyrolysis reaction occurred between 200 and 450 °C at the conversion points (α) ranging from 0.2 to 0.6 while their corresponding reaction parameters including activation energy, enthalpy change, Gibb's free energy and pre-exponential factors were ranged from 165 to 207 kJ mol-1, 169-200 kJ mol-1, 90-42 kJ mol-1, and 1018-1026 s-1, respectively. The narrow range of pre-exponential factors indicated a uniform pyrolysis, while lower differences between enthalpy change and activation energies indicated that reactions were thermodynamically favorable. The evolved gases were dominated by propanoic acid, 3-hydroxy-, hydrazide, hydrazinecarboxamide and carbohydrazide followed by amines/amides, alcohols, acids, aldehydes/ketones, and esters.