Zinc Oxide Nanoparticles Modulates the Production of β-Glucosidase and Protects its Functional State Under Alcoholic Condition in Saccharomyces cerevisiae

Effect of nickel oxide nanoparticles on bioethanol production by Pichia kudriavzveii IFM 53048 using banana peel waste substrate

The use of nanomaterials in bioethanol production is promising and on the increase. In this report, the effect of nickel oxide nanoparticles (NiO NPs) on bioethanol production in the presence of a novel yeast strain, Pichia kudriavzveii IFM 53048 isolated from banana wastes was investigated. The hot percolation method was employed for the green synthesis of NiO NPs. The logistic and modified Gompertz kinetic models employed in this study showed a 0.99 coefficient of determination (R2) on cell growth, and substrate utilization on the initial rate data plot which indicate that these model were best suited for bioethanol production studies. As a result, 99.95% of the substrate was utilized to give 0.23 g/L/h-1 bioethanol productivity, and 51.28% fermentation efficiency, respectively. At 0.01 wt% of NiO NPs, maximum production was achieved with 0.27 g/g bioethanol yield. Meanwhile, 0.78 h-1 maximum specific growth rate (µmax) of the microorganism, 3.77 g/L bioethanol concentration (Pm), 0.49 g/L/h production rate (rp.m), and 2.43 h production lag time (tL) were obtained when 0.01 wt% of NiO NPs were used during the bioethanol production process. However, a decrease in bioethanol concentrations occurred at ≥0.02 wt% of NiO NPs. The incorporation of NiO NPs in the simultaneous saccharification and fermentation (SSF) process improved the production of bioethanol by 1.90 fold using banana peel wastes as substrate. These revealed NiO NPs could serve as a suitable biocatalyst in the green production of bioethanol from banana peel waste materials.

Dual strategy for bioconversion of elephant grass biomass into fermentable sugars using Trichoderma reesei towards bioethanol production

In this study, biodelignification and enzymatic hydrolysis of elephant grass were performed by recombinant and native strain of Trichoderma reesei, respectively. Initially, rT. reesei displaying Lip8H and MnP1 gene was used for biodelignification with NiO nanoparticles. Saccharification was performed by combining hydrolytic enzyme produced with NiO nanoparticles. Elephant grass hydrolysate was used for bioethanol production using Kluyveromyces marxianus. Maximum lignolytic enzyme production was obtained with 15 µg/L of NiO nanoparticles and initial pH of 5 at 32 °C. Subsequently, about 54% of lignin degradation was achieved after 192 h. Hydrolytic enzymes showed elevated enzyme activity and resulted in 84.52 ± 3.5 g/L of total reducing sugar at 15 µg/mL NiO NPs. About 14.65 ± 1.75 g/L of ethanol was produced using K. marxianus after 24 h. Thus, dual strategy employed for conversion of elephant grass biomass into fermentable sugar and subsequent biofuel production could become potential platform for commercialization.

Impact of nanoparticle inclusion on bioethanol production process kinetic and inhibitor profile

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NiO nanoparticle (NP) inclusion enhanced bioethanol production up to 59.96 %.

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Band energy gap impact NP catalytic performance in bioethanol production.

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NiO nanoparticle biocatalyst improved bioethanol productivity by 145 %.

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Modified Gompertz model was used to describe ethanol production with NP inclusion.

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Metallic NiO nanoparticles significantly reduced acetic acid concentration by 110 %.

This study examines the effects of nanoparticle inclusion in instantaneous saccharification and fermentation (NIISF) of waste potato peels. The effect of nanoparticle inclusion on the fermentation process was investigated at different stages which were: pre-treatment, liquefaction, saccharification and fermentation. Inclusion of NiO NPs at the pre-treatment stage gave a 1.60-fold increase and 2.10-fold reduction in bioethanol and acetic acid concentration respectively. Kinetic data on the bioethanol production fit the modified Gompertz model (R ² > 0.98). The lowest production lag time (t _L) of 1.56 h, and highest potential bioethanol concentration (P _m) of 32 g/L were achieved with NiO NPs inclusion at different process stages; the liquefaction stage and the pre-treatment phase, respectively. Elevated bioethanol yield, coupled with substantial reduction in process inhibitors in the NIISF processes, demonstrated the significance of point of nanobiocatalysts inclusion for the scale-up development of bioethanol production from potato peels.

Engineering fungal morphology for enhanced production of hydrolytic enzymes by Aspergillus oryzae SBS50 using microparticles

Effect of microparticles and silver nanoparticles was studied on the production of hydrolytic enzymes by a potent phytase-producing mould, Aspergillus oryzae SBS50. Addition of microparticles, viz. talc powder and aluminum oxide enhanced phytase production from 2894 to 3903 and 2847 to 4204 U/L, cellulase from 2529 to 4931 and 2455 to 3444 U/L, xylanase from 9067 to 9642 and 9994 to 14,783 U/L, amylase from 5880 to 11,000 and 6130 to 13,145 U/L, respectively. Fungal morphology was also engineered by the use of microparticles. Fungal pellet size was significantly reduced (~ 90%) by the addition of microparticles. Fermentation time was reduced from 4 to 3 days after the addition of microparticles, thus increasing the productivity of the enzymes significantly. These results confirmed the importance of microparticles in engineering fungal morphology for enhanced production of hydrolytic enzymes.

The Effects of ZnO Nanoparticles in Combination with Alcohol on Biosynthetic Potential of Saccharomyces cerevisiae

This paper reports about experimental results concerning the influence of 30 nm ZnO nanoparticles on biomass, carbohydrates, β-glucans, proteins accumulation and catalase enzyme activity at Saccharomyces cerevisiae CNMN-Y-20 yeast strain exposed to alcohol action. Alcohol in concentrations of 2%, 5% and 10% added to culture medium has been reported to stimulate β-glucans biosynthesis and to inhibit protein synthesis. Low biomass production, with 71% less that control, was detected in the experiments with 10% alcohol. ZnO nanoparticles in combination with alcohol do not offer sufficient protection for the proteins biosynthesis, but efficiently protect the carbohydrates and β-glucans biosynthetic processes, which contents in the biomass are with 16.6% and 19.9% higher than control, respectively. The maximum value of β-glucans content was established in case of cultivation of selected yeast strain on YPD medium supplemented with 5 mg/L nanoparticles ZnO and 2% alcohol. The obtained results allowed the elaboration of new procedure for directed synthesis of β-glucans that contributed to an increase of this component with 30.7%, compared to control.

Graphene Oxide Quantum Dots as Novel Nanozymes for Alcohol Intoxication

Alcohol overconsumption as a worldwide issue results in alcoholic liver disease (ALD), such as steatosis, alcoholic hepatitis, and cirrhosis. The treatment of ALD has been widely investigated but remains challenging. In this work, the protective effects of graphene oxide quantum dots (GOQDs) as novel nanozymes against alcohol overconsumption are discovered, and the specific mechanisms underlying these effects are elucidated via omics analysis. GOQDs dramatically alleviate the reduction of cell viability induced by ethanol and can act as nanozymes to accelerate ethanol metabolism and avoid the accumulation of toxic intermediates in cells. Mitochondrial damage and the excessive generation of free radicals were mitigated by GOQDs. The mechanisms underlying the cellular protective effects were also related to alterations in metabolic and protein signals, especially those involved in lipid metabolism. The moderately increased autophagy induced by GOQDs explained the removal of accumulated lipids and the subsequent elimination of excessive GOQDs. These findings suggest that GOQDs have an antagonistic capacity against the adverse effects caused by ethanol and provide new insights into the direct applications of GOQDs. In addition to traditional antioxidation, this work also establishes metabolomics and proteomics techniques as effective tools to discover the multiple functions of nanozymes.