Bioethanol Production from Azolla filiculoides by Saccharomyces cerevisiae, Pichia stipitis, Candida lusitaniae, and Kluyveromyces marxianus.

Ethanol was produced by separate hydrolysis and fermentation using Azolla filiculoides as a biomass. Thermal acid hydrolysis and enzymatic saccharification were used as pretreatment methods to produce monosaccharides from Azolla. The optimal content for thermal acid hydrolysis of 14% (w/v) Azolla weed slurry produced 16.7-g/L monosaccharides by using 200 mM H2SO4 at 121 °C for 60 min. Enzymatic saccharification using 16 U/mL Viscozyme produced 61.6 g/L monosaccharide at 48 h. Ethanol productions with ethanol yield coefficients from Azolla weed hydrolysate using Kluyveromyces marxianus, Candida lusitaniae Saccharomyces cerevisiae, and Pichia stipitis were 26.8 g/L (YEtOH = 0.43), 23.2 g/L (YEtOH = 0.37), 18.2 g/L (YEtOH = 0.29), and 13.7 g/L (YEtOH = 0.22), respectively. Saccharomyces cerevisiae produces the lowest yield as it utilized only glucose. Bioethanol from Azolla weed hydrolysate can be successfully produced by using Kluyveromyces marxianus because it consumed the mixture of glucose and xylose completely within 60 h.

Emergence of New Disease: How Can Artificial Intelligence Help?

Emergence of new disease remains a critical parameter in human health and society. Advances in artificial intelligence (AI) allow for rapid processing and analysis of massive and complex data. In this forum article, the recent applications across disease prediction and drug development in relation to the COVID-19 pandemic are reviewed.

Comparison of Ethanol Yield Coefficients Using Saccharomyces cerevisiae, Candida lusitaniae, and Kluyveromyces marxianus Adapted to High Concentrations of Galactose with Gracilaria verrucosa as Substrate.

The red seaweed Gracilaria verrucosa has been used for the production of bioethanol. Pretreatment for monosaccharide production was carried out with 12% (w/v) G. verrucosa slurry and 500 mM HNO3 at 121°C for 90 min. Enzymatic hydrolysis was performed with a mixture of commercial enzymes (Cellic C-Tec 2 and Celluclast 1.5 L; 16 U/ml) at 50°C and 150 rpm for 48 h. G. verrucosa was composed of 66.9% carbohydrates. In this study, 61.0 g/L monosaccharides were obtained from 120.0 g dw/l G. verrucosa. The fermentation inhibitors such as hydroxymethylfurfural (HMF), levulinic acid, and formic acid were produced during pretreatment. Activated carbon was used to remove HMF. Wildtype and adaptively evolved Saccharomyces cerevisiae, Candida lusitaniae, and Kluyveromyces marxianus were used for fermentation to evaluate ethanol production.

7-Deoxy-trans-dihydronarciclasine Reduces ß-Amyloid and Ameliorates Memory Impairment in a Transgenic Model of Alzheimer's Disease.

The critical pathological feature of Alzheimer's disease (AD) is the accumulation of ß-amyloid (Aß), the main constituent of amyloid plaques. ß-amyloid precursor protein (APP) undergoes amyloidogenic cleavage by ß- and γ-secretase generating Aß at endosomes or non-amyloidogenic processing by α-secretase precluding the production of Aß at the plasma membrane. Recently, several natural products have been widely researched on the prevention of Aß accumulation for AD treatment. We previously reported that Lycoris chejuensis K. Tae et S. Ko (CJ), which originated from Jeju Island in Korea, improved the disrupted memory functions and reduced Aß production in vivo. Here, we further explored the effect of its active component, 7-deoxy-trans-dihydronarciclasine (coded as E144), on Aß generation and the underlying mechanism. Our results showed that E144 reduced the level of APP, especially its mature form, in HeLa cells overexpressing human APP with the Swedish mutation. Concomitantly, E144 decreased the levels of Aß, sAPPß, sAPPα, and C-terminal fragment. In addition, administration of E144 normalized the behavioral deficits in Tg2576 mice, an APP transgenic mouse model of AD. E144 also decreased the Aß and APP levels in the cerebral cortex of Tg2576 mice. Thus, we propose that E144 could be a potential drug candidate for an anti-amyloid disease-modifying AD therapy.

Non-Dioxin-Like Polychlorinated Biphenyls Inhibit G-Protein Coupled Receptor-Mediated Ca2+ Signaling by Blocking Store-Operated Ca2+ Entry.

Polychlorinated biphenyls (PCBs) are ubiquitous pollutants which accumulate in the food chain. Recently, several molecular mechanisms by which non-dioxin-like (NDL) PCBs mediate neurodevelopmental and neurobehavioral toxicity have been elucidated. However, although the G-protein coupled receptor (GPCR) is a significant target for neurobehavioral disturbance, our understanding of the effects of PCBs on GPCR signaling remains unclear. In this study, we investigated the effects of NDL-PCBs on GPCR-mediated Ca2+ signaling in PC12 cells. We found that ortho-substituted 2,2',6-trichlorinated biphenyl (PCB19) caused a rapid decline in the Ca2+ signaling of bradykinin, a typical Gq- and phospholipase Cß-coupled GPCR, without any effect on its inositol 1,4,5-trisphosphate production. PCB19 reduced thapsigargin-induced sustained cytosolic Ca2+ levels, suggesting that PCB19 inhibits SOCE. The abilities of other NDL-PCBs to inhibit store-operated Ca2+ entry (SOCE) were also examined and found to be of similar potencies to that of PCB19. PCB19 also showed a manner equivalent to that of known SOCE inhibitors. PCB19-mediated SOCE inhibition was confirmed by demonstrating the ability of PCB19 to inhibit the SOCE current and thapsigargin-induced Mn2+ influx. These results imply that one of the molecular mechanism by which NDL-PCBs cause neurobehavioral disturbances involves NDL-PCB-mediated inhibition of SOCE, thereby interfering with GPCR-mediated Ca2+ signaling.

Effect of Lycoris chejuensis and Its Active Components on Experimental Models of Alzheimer's Disease.

We found that an extract of Lycoris chejuensis and its three isolated active components, narciclasine, 7-deoxynarciclasine, and 7-deoxy-trans-dihydronarciclasine, each significantly reduced the formation of amyloid-ß peptides in HeLa cells transfected with an amyloid precursor protein carrying the Swedish mutation up to 45 ± 3.6%. The extract down-regulated amyloid precursor protein, especially the mature form by up to 88%, and reduced the ability of secretases to generate toxic amyloid-ß. Double-transgenic mice treated with the extract for 4 months also showed significantly reduced levels of amyloid-ß and plaques while exhibiting improved memory functions in the Morris water maze and novel object recognition tests. In conclusion, the extract and isolated active components of L. chejuensis decreased the production of amyloid-ß by attenuating amyloid precursor protein levels. Furthermore, the extract improved the disrupted memory functions in animals while inhibiting amyloid plaque formation. Thus, this extract, as well as its active components, could prove beneficial in the treatment of Alzheimer's disease.

O-GlcNAcylation promotes non-amyloidogenic processing of amyloid-ß protein precursor via inhibition of endocytosis from the plasma membrane.

Amyloid-ß protein precursor (AßPP) is transported to the plasma membrane, where it is sequentially cleaved by α-secretase and γ-secretase. This is called non-amyloidogenic pathway since it precludes the production of amyloid-ß (Aß), the main culprit of Alzheimer's disease (AD). Alternatively, once AßPP undergoes clathrin-dependent endocytosis, it can be sequentially cleaved by ß-secretase and γ-secretase at endosomes, producing Aß (amyloidogenic pathway). ß-N-acetylglucosamine (GlcNAc) can be attached to serine/threonine residues of the target proteins. This novel type of O-linked glycosylation is called O-GlcNAcylation mediated by O-GlcNAc transferase (OGT). The removal of GlcNAc is mediated by O-GlcNAcase (OGN). Recently, it is shown that O-GlcNAcylation of AßPP increases the non-amyloidogenic pathway. To investigate the regulatory role for O-GlcNAcylation in AßPP processing, we first tested the effects of inhibitor for OGN, PUGNAc, on AßPP metabolism in HeLa cells stably transfected with Swedish mutant form of AßPP. Increasing O-GlcNAcylated AßPP level increased α-secretase product while decreased ß-secretase products. We found that PUGNAc increased the trafficking rate of AßPP from the trans-Golgi network to the plasma membrane, and selectively decreased the endocytosis rate of AßPP. These events may contribute to the increased AßPP level in the plasma membrane by PUGNAc. Inhibiting clathrin-dependent endocytosis prevented the effect of PUGNAc on Aß, suggesting that the effect of PUGNAc was mainly mediated by decreasing AßPP endocytosis. These results strongly indicate that O-GlcNAcylation promotes the plasma membrane localization of AßPP, which enhances the non-amyloidogenic processing of AßPP. Thus, O-GlcNAcylation of AßPP can be a potential therapeutic strategy for AD.