Identification of Scopoletin and Chlorogenic Acid as Potential Active Components in Sunflower Calathide Enzymatically Hydrolyzed Extract towards Hyperuricemia

It is known that sunflower (Helianthus annuus L.) calathide enzymatically hydrolyzed extract (SCHE) contributes to the regulation of serum uric acid (UA); however, evidence regarding its bioactive components and mechanism are lacking. We identified two water-soluble components (scopoletin and chlorogenic acid) that are abundant in sunflower calathide, especially evaluated for the inhibition of xanthine oxidase (XO) and the expression levels of urate transporters with SCHE. Molecular docking of a chlorogenic acid–XO complex was more stable than that of the Scopoletin–XO, and its binding pockets, which closed the Mo = S center, was similar to xanthine pockets. Moreover, chlorogenic acid exhibited stronger inhibition than that of the scopoletin below 260 μM, despite the IC50 of scopoletin (577.7 μM) being lower than that chlorogenic acid (844.7 μM) on the UA generation assessed by a spectrophotometer in vitro. It revealed that chlorogenic acid and scopoletin were competitive inhibitors of XO. In addition, the SCHE (300 μg/mL) and chlorogenic acid (0.75 mM) obviously inhibited urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) expression levels, while scopoletin significantly upregulated the expression of GLUT9. To summarize, chlorogenic acid served a crucial role in UA regulation consistent with the SCHE and functioned as an important ingredient of SCHE. The strategic analysis of SCHE combined with scopoletin and chlorogenic acid may contribute to the development of food supplemental alternatives on UA metabolism and the reduction of agricultural byproduct waste.

A multi-omics approach to lignocellulolytic enzyme discovery reveals a new ligninase activity from Parascedosporium putredinis NO1

Lignocellulose, the structural component of plant cells, is a major agricultural byproduct and the most abundant terrestrial source of biopolymers on Earth. The complex and insoluble nature of lignocellulose limits its conversion into value-added commodities, and currently, efficient transformation requires expensive pretreatments and high loadings of enzymes. Here, we report on a fungus from the Parascedosporium genus, isolated from a wheat-straw composting community, that secretes a large and diverse array of carbohydrate-active enzymes (CAZymes) when grown on lignocellulosic substrates. We describe an oxidase activity that cleaves the major β-ether units in lignin, thereby releasing the flavonoid tricin from monocot lignin and enhancing the digestion of lignocellulose by polysaccharidase mixtures. We show that the enzyme, which holds potential for the biorefining industry, is widely distributed among lignocellulose-degrading fungi from the Sordariomycetes phylum.

Fixed-bed Adsorption of Congo red dye and Bisphenol A from solution onto surfactant modified walnut shell

Wastewater stemming from industries may contain pollutants such as synthetic dyes and endocrine-disrupting chemicals which are known to be harmful to living organisms. Therefore, to safeguard the wellbeing of humankind and environmental safety, it is imperative for industrial effluents to be sanitized before their discharged into water bodies. Furthermore, to explore the utilization of agricultural byproduct is valuable to study. To achieve this, a Cetyltrimethylammonium bromide functionalized Walnut shells (WNS-CTAB) were prepared to remove pollutants in column approach. The column work was carried out for diverse working conditions. There is in favor of adsorption at low influent pollutant concentration, low flow rate or high bed depth. As the highest breakthrough time of 113 and 23 min at flow rate 6 mL min −1 was recorded for both CR and BPA, respectively, the Yan’s kinetic model best described the breakthrough curve. The adsorbent showed better regeneration capabilities; accordingly can offer practical use for adsorption of CR and BPA from wastewaters.

Engineering cofactor supply and NADH-dependent d-galacturonic acid reductases for redox-balanced production of l-galactonate in Saccharomyces cerevisiae

d-Galacturonic acid (GalA) is the major constituent of pectin-rich biomass, an abundant and underutilized agricultural byproduct. By one reductive step catalyzed by GalA reductases, GalA is converted to the polyhydroxy acid l-galactonate (GalOA), the first intermediate of the fungal GalA catabolic pathway, which also has interesting properties for potential applications as an additive to nutrients and cosmetics. Previous attempts to establish the production of GalOA or the full GalA catabolic pathway in Saccharomyces cerevisiae proved challenging, presumably due to the inefficient supply of NADPH, the preferred cofactor of GalA reductases. Here, we tested this hypothesis by coupling the reduction of GalA to the oxidation of the sugar alcohol sorbitol that has a higher reduction state compared to glucose and thereby yields the necessary redox cofactors. By choosing a suitable sorbitol dehydrogenase, we designed yeast strains in which the sorbitol metabolism yields a “surplus” of either NADPH or NADH. By biotransformation experiments in controlled bioreactors, we demonstrate a nearly complete conversion of consumed GalA into GalOA and a highly efficient utilization of the co-substrate sorbitol in providing NADPH. Furthermore, we performed structure-guided mutagenesis of GalA reductases to change their cofactor preference from NADPH towards NADH and demonstrated their functionality by the production of GalOA in combination with the NADH-yielding sorbitol metabolism. Moreover, the engineered enzymes enabled a doubling of GalOA yields when glucose was used as a co-substrate. This significantly expands the possibilities for metabolic engineering of GalOA production and valorization of pectin-rich biomass in general.

Model-based application for adsorption of Lead (II) from aqueous solution using low-cost jute stick derived activated carbon

Background: Removal of lead (II) ions from supply water using an inexpensive adsorbent is essential. It is recommended that low-cost adsorbents are developed to effectively remove lead (II) ions from aqueous solutions. The aim of the study is to develop and validate models for predicting the performance of carboxylated jute stick derived activated carbon (JSAC-COOH) in removing lead (II) ions from aqueous solution, which can assist the water supply authorities in supplying lead (II) free drinking water to the communities at a low-cost. Methods: Controlled laboratory experiments were conducted following the statistical “Design of Experiments” through varying the factors affecting the performance of JSAC-COOH in removing lead (II) ions. The performance of JSACCOOH was investigated for different concentrations of lead (II) ions (range: 50 - 500 mg/L) at variable experimental conditions (temperature: 15°C and 27°C; pH: 4.0 and 7.0) and time (1, 10, 30 and 60 min). Several models (Linear and non-linear) were investigated and validated for predicting the concentrations of lead (II) ions in aqueous solution. Results: The prepared JSAC-COOH had a surface area of 615.3 m2 /g. In 60 min, up to 99.8% removal of lead (II) ions was achieved. Few models showed very good to excellent predictive capabilities with coefficients of determination in the range of 0.85–0.95. The model validation experiments showed the correlation coefficients in the range of 0.84 – 0.98. Conclusion: The models have the capabilities to reasonably predict the final concentrations of lead (II) ions, which can be used in controlling the effluent lead (II) ion concentrations. The proposed adsorbent is likely to be low-cost as it was developed using the commonly available agricultural byproduct.

Green Synthesis of Antileishmanial and Antifungal Silver Nanoparticles Using Corn Cob Xylan as a Reducing and Stabilizing Agent

Corn cob is an agricultural byproduct that produces an estimated waste burden in the thousands of tons annually, but it is also a good source of xylan, an important bioactive polysaccharide. Silver nanoparticles containing xylan (nanoxylan) were produced using an environmentally friendly synthesis method. To do this, we extracted xylan from corn cobs using an ultrasound technique, which was confirmed by both chemical and NMR analyses. This xylan contained xylose, glucose, arabinose, galactose, mannose, and glucuronic acid in a molar ratio of 50:21:14:9:2.5:2.5, respectively. Nanoxylan synthesis was analyzed using UV–vis spectroscopy at kmax = 469 nm and Fourier transform infrared spectroscopy (FT-IR), which confirmed the presence of both silver and xylan in the nanoxylan product. Dynamic light scattering (DLS) and atomic force microscopy (AFM) revealed that the nanoxylan particles were ~102.0 nm in size and spherical in shape, respectively. DLS also demonstrated that nanoxylan was stable for 12 months and coupled plasma optical emission spectrometry (ICP-OES) showed that the nanoxylan particles were 19% silver. Nanoxylan reduced Leishmania amazonensis promastigote viability with a half maximal inhibitory concentration (IC50) value of 25 μg/mL, while xylan alone showed no effective. Additionally, nanoxylan exhibited antifungal activity against Candida albicans (MIC = 7.5 μg/mL), C. parapsilosis (MIC = 7.5 μg/mL), and Cryptococcus neoformans (MIC = 7.5 μg/mL). Taken together, these data suggest that it is possible to synthesize silver nanoparticles using xylan and that these nanoxylan exert improved antileishmanial and antifungal activities when compared to the untreated polysaccharide or silver nitrate used for their synthesis. Thus, nanoxylan may represent a promising new class of antiparasitic agents for use in the treatment of these microorganisms.

Effects of nutriental and environmental conditions on carotenoid biosynthesis by Rhodotorula sp.

Carotenoid compounds are popular natural antioxidants which are commonly isolated from the plants. Recently, there have been many researches on carotenoid biosynthesis towards low cost products. In this study, Rhodotorula sp. was grown on an agricultural byproduct (corncobs) as a matrix in solid-state fermentation. Essential nutrients were added with different concentrations to optimize condition for the carotenoid biosynthesis. Effects of other environmental factors such as moisture content and fermentation time on the yield were also characterized. The optimal nutrient composition for the yeast’s growth and carotenoid biosynthesis is a compound of 500μg nitrogen and 16mg carbon in 100g matrix. Additionally, the moisture content of 80% is the best for producing carotenoid by this yeast strain. The fermentation time for the highest carotenoid yield is observed after 8 days.