Improved glucose recovery from durian peel by alkaline-catalyzed steam pretreatment

Durian (Durio zibethinus Murr.) peel, as agricultural waste, is a potential under-utilized lignocellulosic biomass that is sufficiently available in Thailand. In this study, durian peel from monthong (D. zibethinus Murr. cv. Monthong) and chanee (D.zibethinus Murr. cv. Chanee) were subjected to pretreatment with sodium hydroxide (NaOH) under autoclaving conditions to improve glucose recovery. The effect of NaOH concentration (1%, 2%, 3%, and 4%) and autoclave temperature (110 °C, 120 °C, and 130 °C) was investigated based on the amount of glucose recovered. The optimal NaOH concentration and autoclave temperature were determined to be 2% and 110 °C, respectively, under which maximum glucose (36% and 35% in monthong and chanee peels, respectively) was recovered. Glucose recovery was improved by about 6-fold at the optimal pretreatment condition for both pretreated monthong and chanee when compared to the untreated durian peels. Scanning electron microscopy (SEM) showed great changes to the surface morphology of pretreated durian peel from the two cultivars. X-ray diffraction (XRD) analysis also revealed a rise in cellulose crystallinity index (CrIs) after pretreatment. A combination of mild NaOH concentration and autoclaving is a very effective pretreatment technique for maximum glucose recovery from durian peel.

Dasiglucagon: A Next-Generation Glucagon Analog for Rapid and Effective Treatment of Severe Hypoglycemia Results of Phase 3 Randomized Double-Blind Clinical Trial

OBJECTIVE To evaluate the efficacy and safety of dasiglucagon – a ready-to-use, next-generation glucagon analog in aqueous formulation for subcutaneous dosing – for treatment of severe hypoglycemia in adults with type 1 diabetes. <p>RESEARCH DESIGN AND METHODS This randomized, double-blind trial included 170 adult participants with type 1 diabetes, each randomized to receive a single subcutaneous dose of dasiglucagon 0.6 mg, placebo, or reconstituted glucagon 1 mg (2:1:1 randomization) during controlled insulin-induced hypoglycemia. The primary endpoint was time to plasma glucose recovery, defined as an increase of ≥20 mg/dL from baseline without rescue intravenous glucose. The primary comparison was dasiglucagon versus placebo; reconstituted lyophilized glucagon was included as reference.</p> <p>RESULTS Median (95% CI) time to recovery was 10 (10, 10) minutes for dasiglucagon compared to 40 (30, 40) minutes for placebo (<i>P</i><0.001); the corresponding result for reconstituted glucagon was 12 (10, 12) minutes. In the dasiglucagon group, plasma glucose recovery was achieved within 15 minutes in all but one participant (99%), superior to placebo (2%; <i>P</i><0.001) and similar to glucagon (95%). Similar outcomes were observed for the other investigated time points at 10, 20 and 30 minutes after dosing. The most frequent side effects were nausea and vomiting, as expected for glucagon treatment.</p> <p>CONCLUSIONS Dasiglucagon provided rapid and effective reversal of hypoglycemia in adults with type 1 diabetes, with safety and tolerability similar to that reported for reconstituted glucagon injection. The ready-to-use, aqueous formulation of dasiglucagon offers the potential to provide a rapid and reliable treatment for severe hypoglycemia.</p>

Dasiglucagon: A Next-Generation Glucagon Analog for Rapid and Effective Treatment of Severe Hypoglycemia Results of Phase 3 Randomized Double-Blind Clinical Trial

OBJECTIVE To evaluate the efficacy and safety of dasiglucagon – a ready-to-use, next-generation glucagon analog in aqueous formulation for subcutaneous dosing – for treatment of severe hypoglycemia in adults with type 1 diabetes. <p>RESEARCH DESIGN AND METHODS This randomized, double-blind trial included 170 adult participants with type 1 diabetes, each randomized to receive a single subcutaneous dose of dasiglucagon 0.6 mg, placebo, or reconstituted glucagon 1 mg (2:1:1 randomization) during controlled insulin-induced hypoglycemia. The primary endpoint was time to plasma glucose recovery, defined as an increase of ≥20 mg/dL from baseline without rescue intravenous glucose. The primary comparison was dasiglucagon versus placebo; reconstituted lyophilized glucagon was included as reference.</p> <p>RESULTS Median (95% CI) time to recovery was 10 (10, 10) minutes for dasiglucagon compared to 40 (30, 40) minutes for placebo (<i>P</i><0.001); the corresponding result for reconstituted glucagon was 12 (10, 12) minutes. In the dasiglucagon group, plasma glucose recovery was achieved within 15 minutes in all but one participant (99%), superior to placebo (2%; <i>P</i><0.001) and similar to glucagon (95%). Similar outcomes were observed for the other investigated time points at 10, 20 and 30 minutes after dosing. The most frequent side effects were nausea and vomiting, as expected for glucagon treatment.</p> <p>CONCLUSIONS Dasiglucagon provided rapid and effective reversal of hypoglycemia in adults with type 1 diabetes, with safety and tolerability similar to that reported for reconstituted glucagon injection. The ready-to-use, aqueous formulation of dasiglucagon offers the potential to provide a rapid and reliable treatment for severe hypoglycemia.</p>

Calcium peroxide pretreatment to facilitate the delignification and enzymatic hydrolysis of wheat straw

Calcium peroxide (CaO2) pretreatment was employed to remove lignin and subsequently facilitate enzymatic digestibility of wheat straw. An optimal condition was obtained at 130°C for 10 min with 0.35 g CaO2/g dried material of wheat straw and a 1:8 solid-liquid ratio. Under this condition, 57.8% of initial lignin, 7.2% of initial glucan, and 30.6% of initial xylan were removed from CaO2 pretreatment, respectively, meanwhile, a glucose recovery of 90.6 % and a xylose recovery of 65.9 % were obtained from the subsequent enzymatic hydrolysis of treated wheat straw, respectively. CaO2 pretreatment was proved to be a very effective method in delignification and improving enzymatic digestibility. Compared to raw material, the complex structure of lignocellulose was drastically disrupted with a wide emergence of scaly bulges and fully exposed microfibers, which still retained in the solid.

Improved Glucose Recovery from Sicyos angulatus by NaOH Pretreatment and Application to Bioethanol Production

As greenhouse gases and environmental pollution become serious, the demand for alternative energy such as bioethanol has rapidly increased, and a large supply of biomass is required for bioenergy production. Lignocellulosic biomass is the most abundant on the planet and a large part of it, the second-generation biomass, has the advantage of not being a food resource. In this study, Sicyos angulatus, known as an invasive plant (harmful) species, was used as a raw material for bioethanol production. In order to improve enzymatic hydrolysis, S. angulatus was pretreated with different NaOH concentration at 121 °C for 10 min. The optimal NaOH concentration for the pretreatment was determined to be 2% (w/w), and the glucan content (GC) and enzymatic digestibility (ED) were 46.7% and 55.3%, respectively. Through NaOH pretreatment, the GC and ED of S. angulatus were improved by 2.4-fold and 2.5-fold, respectively, compared to the control (untreated S. angulatus). The hydrolysates from S. angulatus were applied to a medium for bioethanol fermentation of Saccharomyces cerevisiae K35. Finally, the maximum ethanol production was found to be 41.3 g based on 1000 g S. angulatus, which was 2.4-fold improved than the control group.

Combining Autoclaving with Mild Alkaline Solution as a Pretreatment Technique to Enhance Glucose Recovery from the Invasive Weed Chloris barbata

Developing an optimum pretreatment condition to enhance glucose recovery assessed the potential of Chloris barbata, which is a common invasive weed in Thailand, as a feedstock for bioethanol production. Chloris barbata was exposed to autoclave-assisted alkaline pretreatment by using different sodium hydroxide (NaOH) concentrations (1% to 4%) and heat intensities (110 °C to 130 °C) that were dissipated from autoclaving. The optimum condition for pretreatment was determined to be 2% NaOH at 110 °C for 60 min. At this condition, maximum hydrolysis efficiency (90.0%) and glucose recovery (30.7%), as compared to those of raw C. barbata (15.15% and 6.20%, respectively), were observed. Evaluation of glucose production from 1000 g of C. barbata based on material balance analysis revealed an estimated yield of 304 g after pretreatment at the optimum condition when compared to that of raw C. barbata (61 g), an increase of five-fold. Structural analysis by the scanning electron microscopy (SEM) and X-ray diffraction (XRD) revealed the disruption of the intact structure of C. barbata and an increase in the cellulose crystallinity index (CrI), respectively. The results from this study demonstrate the efficiency of using C. barbata as a potential feedstock for bioethanol production.

Effect of delignification on hemicellulose extraction from switchgrass, poplar, and pine and its effect on enzymatic convertibility of cellulose-rich residues

Hemicellulose is an abundant and underutilized carbohydrate polymer in plants. The objective of this study was to understand the effect of delignification on hemicellulose extraction efficiency with different types of lignocellulosic biomass. In the case of pine, with a prior sodium chlorite or peracetic acid delignification, more than 50% of the original hemicellulose in the biomass could be extracted using a 10% sodium hydroxide solution; without delignification, only 3.4% of hemicellulose could be extracted from pine. In contrast, without prior delignification, acceptable hemicellulose extraction efficiencies (55.5% and 50.7%, respectively) were achieved from switchgrass and poplar. In addition, the effect of hemicellulose extraction processes on the enzymatic convertibility of the cellulose-rich residues after extraction was determined. The cellulose-rich residues from switchgrass after hemicellulose alkali extraction showed high glucose recovery with enzyme hydrolysis with or without prior delignification. For pine and poplar, high glucose recovery with enzyme hydrolysis of the cellulose-rich residues only occurred if the sample had a delignification step prior to hemicellulose extraction. This information on commercially available biomass feedstocks is useful for those considering isolating hemicellulose within a biorefinery concept.