Yield Of Glycosides Research Articles

Optimizing Biomass and Steviol Glycoside Yield in Hydroponically Grown Stevia (Stevia rebaudiana Bertoni) with Ammonium Nitrate and 6-Benzylaminopurine Concentrations

Optimizing Biomass and Steviol Glycoside Yield in Hydroponically Grown Stevia (Stevia rebaudiana Bertoni) with Ammonium Nitrate and 6-Benzylaminopurine Concentrations

The Effect of Spraying with the Hormone Brassinolide on the Production of Oil and Glycosides of Goat Pea (Securigera securidaca)

A field experiment was carried out in Diyala Governorate during the winter season 2020-2021 to evaluate the effect of spraying three concentrations of Brassinolide hormone (1, 2 and 3 ppm) in addition to the control treatment (0 ppm) and three dates of spraying (after 20,40 and 60 days of germination) in the production of oil and total glycosides in Securigera securidaca seeds, by using a factorial experiment according to the randomized complete block design. The results showed that the spraying treatment with a concentration of 2 ppm was superior in seed yield, content and yield of oil, and content of total glycosides in the seeds, which reached 9.76 g/plant, 4.00%, 15.43 kg/ha and 1.770 mg/100 g seeds respectively, while the second date of spraying with the hormone Brassinolide was superior in seed yield, content and yield of oil, and total glycosides, reached 9.39 g/plant, 3.76%, 13.15 kg/ha and 1.750 mg/100 g seeds respectively. The results also show that the interaction treatment was superior at concentration 2ppm in the second date and gave the highest content and yield of oil and total glycosides which reached 4.24%, 17.54 kg/ha and 1.820 mg/100 g seeds respectively.

Extraction, Purification, and Component Identification of Monoterpene Glycosides from Paeonia suffruticosa Seed Meal.

Paeonia suffruticosa (P. suffruticosa) seed meal is a byproduct of P. suffruticosa seed processing, which contains bioactive substances such as monoterpene glycosides, and has not been effectively utilized at present. In this study, monoterpene glycosides were extracted from P. suffruticosa seed meal using an ultrasound-assisted ethanol extraction process. The monoterpene glycoside extract was then purified by macroporous resin and identified using HPLC-Q-TOF-MS/MS. The results indicated the following optimal extraction conditions: ethanol concentration, 33%; ultrasound temperature, 55 °C; ultrasound power, 400 W; liquid-material ratio, 33:1; and ultrasound time, 44 min. Under these conditions, the yield of monoterpene glycosides was 121.03 mg/g. The purity of the monoterpene glycosides increased from 20.5% (crude extract) to 71.2% (purified extract) when using LSA-900C macroporous resin. Six monoterpene glycosides (oxy paeoniflorin, isomaltose paeoniflorin, albiflorin, 6'-O-β-D-glucopyranoside albiflorin, paeoniflorin, and Mudanpioside i) were identified from the extract using HPLC-Q-TOF-MS/MS. The main substances were albiflorin and paeoniflorin, and the contents were 15.24 mg/g and 14.12 mg/g, respectively. The results of this study can provide a theoretical basis for the effective utilization of P. suffruticosa seed meal.

Heritability and genetic variance estimates for agronomic traits and glycoside yield in four elite stevia breeding populations

AbstractHeritability estimates of traits assist breeders in optimizing cultivar development and can help predict gain from selection in breeding programs. Narrow‐sense heritabilities were measured in agronomic traits and glycoside concentration in four elite stevia (Stevia rebaudiana Bertoni) populations using half‐sib family analysis. Gain from selection at 20% selection intensity was estimated for morphological, yield, and glycoside traits. Experiments were conducted in two field locations in North Carolina. Variation was observed across cultigens for agronomic traits including stem height, branch width, and leaf size, for both subjective and objective measurements. Yield, lodging resistance, disease resistance, and percent survival showed a high genetic variation across cultigens. In addition, glycosides including Reb A, Reb C, and Reb D also showed high variation by cultigen. Heritability estimates for plant morphological traits were highest for stem height, and moderate for yield and branch width. However, other traits such as leaf area and lodging resistance showed low heritability (0.10). Glycosides including Reb A, Reb C, Reb D, stevioside and total steviol glycosides (TSG) showed high heritability. The estimated gain from selection per year for stem height (24 mm/year), leaf area (131 mm2/year) and yield (dry weight) (1.2 Mg/ha per year) suggest significant improvements are possible per breeding cycle. The estimated gain for glycoside concentration and percent of TSG of Reb A (26.44 mg/g, 14.51%), Reb C (20.20 mg/g, 20.17%), Reb D (1.70 mg/g, 1.49%), stevioside (6.73 mg/g, 10.72%), and TSG (20.90 mg/g), similarly, indicate significant gains are possible per breeding cycle.

From medicinal and food homologous biomass to total glycosides in Rehmannia glutinosa leaves extracts: Microemulsion-based negative pressure cavitation-assisted extraction

Food-grade and sustainable peppermint oil microemulsion was prepared through gradual screening of components for extraction of total glycosides in Rehmannia glutinosa leaves. The optimal microemulsion was: 6:3:1:25.71 (Tween 80: ethanol: peppermint oil: 0.02 mol/L KCl, w-w:w:w). 1 mol/L KCl solution was used for back-extraction to achieve sustainability of microemulsion. Microemulsion could be used at least 4 cycles. To optimize sustainability of microemulsion, negative pressure cavitation-assisted extraction technology was used as an auxiliary method. Which also makes extraction more suitable for large-scale industrial production. Consequently, microemulsion-based negative pressure cavitation-assisted extraction technology was developed. The optimal conditions for technology were as follows: 5.5 of pH, 37 min of time, and 10 mL/g of liquid-solid ratio. The yield of total glycosides was 45.13 mg/g. This newly established technology, as a cleaner alternative approach, can therefore be used to extract total glycosides from Rehmannia glutinosa leaves.

Cardioprotective and Hepatoprotective Effects of Ixora pavetta and Tecoma capensis Leaf Extracts

Background: Ixora pavetta and Tecoma capensis are two less explored and neglected plants species in medicinal prospective. The flowers bark and root of I. pavetta used as a remedy for cough, anaemia, women urinary problems. The bark powder of Tecoma capensis useful in treating fever, pneumonia, stomach problems and improve blood clotting. The role of leaves from these plants in medical practices is not yet clearly determined. The present work aimed to examine the potentiality of their leaf extracts in treating cardiovascular and chronic liver diseases. Materials and Methods: Solvent extraction method is used to extract the bioactive components. The leaf extracts were tested for the existence of cardiac glycosides. The cardioprotective activity and hepatoprotective activity were done using isoproterenol method and MTT assay respectively. Results: The leaf extracts of both plants showed the presence of cardiac glycosides and the leaf extracts of T. capensis recorded a high yield of cardiac glycosides. Leaf methanolic extract (200 mg/kg) of T. capensis exhibited significant depletion in total cholesterol 108.11 mg/dL, tryglcerides 81.48 mg/dL and LDL cholesterol 93.15 mg/ dL in Wistar rats. The I. pavetta leaf methanolic extracts recorded moderate protective activity by increasing the concentrations against H2O2 pre-stimulated HepG2 cells. Conclusion: The extracts of both plants exhibited good cardioprotective activity and hepatoprotective activity. The leaf methanolic extracts of T. capensis reported more cardioprotective activity whereas the leaf methanolic extracts of I. pavetta showed significant hepatoprotective potentiality

Multicomponent natural deep eutectic solvents: Super solvents for the efficient extraction of steviol glycosides (rebaudioside A) from Stevia rebaudiana

Using biomass to produce valuable chemicals has tremendous economic significance; however, in some cases, it poses environmental challenges due to the use of organic solvents. NAtural Deep Eutectic Solvents (NADESs), a sustainable and bio-based functional liquid medium, can be a greener substitute for organic solvents to extract chemical scaffolds from biomass. Although water is an environmental-friendly solvent, it's challenging to tune its selectivity toward extracting a particular class of molecules from biomass. In contrast, NADESs selectivity toward extracting diverse types of molecules can be easily adjusted by a simple variation of the molar ratios of its components. In the current study, Stevia rebaudiana, a well-known calorie-free sweetener, was targeted to extract steviol glycosides. The quantification results revealed that NADES 50 (lactic acid: glycerol: malic acid: glucose, 1:1:1:1) was most efficient to extract, e.g., 38.24 ± 2.22 mg/g and 114.58 ± 5.89 mg/g of rebaudioside A (SG2) and stevioside (SG3), respectively. However, NADES 36 (choline chloride: lactic acid: oxalic acid: glycerol, 2:2:1:1) extracted all targeted analytes (90.69 ± 3.10 mg/g) along with untargeted compounds. The extraction carried out with the optimized parameters was improved by 33.77% and 24.86% in terms of extraction yields of steviol glycosides by NADES 50 and NADES 36, respectively. The crude steviol glycosides were efficiently separated from the NADESs using HP-20 resin. The extraction efficiency of recovered NADES was 30–36% lower than that of their fresh counterparts. The structure of both NADES i.e., NADES 50 and NADES 36 matrices, was characterized by NMR spectroscopy to confirm their structural arrangement. The current study concluded that multicomponent NADESs have excellent extractability of steviol glycosides from the leaves of S. rebaudiana compared to binary NADESs.

Optimization of ultrasonic-assisted extraction of flavonoids, polysaccharides, and eleutherosides from Acanthopanax senticosus using response surface methodology in development of health wine

Acanthopanax senticosus has been widely studied for its various active ingredients such as flavonoids, polysaccharides, and glycosides, while its application in the field of health food has not been reported. This study was conducted to optimize the ultrasonic-assisted extraction method of functional components in Acanthopanax senticosus based on single-factor experiments and Box-Behnken's response surface methodology. The optimal extraction conditions were determined as a solid-to-liquid ratio of 1:10 g/mL, extraction time of 35 min, and power of 200 W, and the actual yields of polysaccharides, flavonoids, and glycosides obtained were 37.27 ± 0.17, 14.83 ± 0.11, and 1.57 ± 0.03 mg/g, respectively. Then, the extract was added to rice wine to formulate Acanthopanax senticosus health wine and analyzed for its antioxidant activity, sensory characteristics, and flavor components. The results showed that ultrasonic-assisted extraction significantly improved the antioxidant activity and imparted good sensory characteristics to Acanthopanax senticosus health wine. HS-SPME-GC-MS analysis further demonstrated that the health wine has a unique flavor profile and can be further produced for application in functional foods and pharmaceuticals.

Transglycosylation by β-mannanase TrMan5A variants and enzyme synergy for synthesis of allyl glycosides from galactomannan

Retaining β-mannanases are glycoside hydrolases (GHs) that can potentially be applied for synthesis of glycosides by catalysis of transglycosylation reactions. A novel active-site double mutant (R171K/E205D) of the catalytic module (CM) of the family GH5 Trichoderma reesei β-mannanase (TrMan5A) was expressed in Pichia pastoris and purified. TrMan5A, CM and CM-variants R171K and R171K/E205D had pH optima between pH 4.0–5.3 and showed >80 % remaining activity after incubation at 40 °C for 48 h. The enzymes were screened for transglycosylation capacity toward oligomeric and polymeric donor substrates and alcohol acceptors using mass-spectrometry. Hydrolysis and transglycosylation products were analysed by a novel HPLC procedure using an NH2 column. R171K/E205D was superior in reactions with mannotetraose and the acceptor allyl alcohol, it had twice as high propensity for transglycosylation as wild-type TrMan5A. Wild-type TrMan5A produced the highest amounts of allyl β-mannosides (with 1–3 mannosyls) from locust bean galactomannan. Applying enzyme synergy, adding the GH27 guar α-galactosidase to the reaction (to cleave off galactomannan side-groups), gave a 2.1-fold increase of allyl mannosides and simultaneously a significant production of allyl galactopyranoside, increasing overall yield of allyl glycosides 4.4-fold, from 2.2% to 9.8%. The enzymatic synthesis of reactive allyl glycosides opens up for production of novel biomaterials and glycopolymers.

The productivity of Stevia rebaudiana (Bertoni) on dry leaves and steviol glycosides of four varieties grown in six regions of Morocco

Stevia rebaudiana Bertoni, is a perennial herbaceous plant native to Paraguay. This plant produces diterpene glycosides that are powerful natural low calorie sweeteners , about 300 times sweeter than saccharose. Stevia has now become an important agricultural crop for the production of a high-potency natural sweetener. Cultural practices are still in development and the productivity potential of desirable steviol glycosides in more or less stable proportions and under different agriculture conditions are largely unknown. Currently, commercial growers and processors all over the world are seeking to maximize the productivity of rebaudioside A , a steviol glycoside . The present study aimed to characterize the effects of region and varieties on stevia dry leaf yield, steviol glycoside content, and steviol glycoside yield under Moroccan conditions. The content of steviol glycosides obtained from dry leaves of four varieties of Stevia rebaudiana , compared to the edaphoclimatic conditions in six different areas in Morocco, was determined using High-Performance Liquid Chromatography (HPLC). Dry leaf yield, leaf steviol glycoside content, and leaf steviol glycoside yield varied according to varieties and regions, with significant interaction of varieties by regions. Dry leaf yield varied from 1.57 to 7.86 t/ha. Stevioside yield ranged from 57.04 to 739.77 kg/ha and rebaudioside A yield varied between 60.8 and 614.04 kg/ha, with Reb A/STV ratios that reached up to 2.62. The total of steviol glycosides yield ranged from 163.21 to 1353.2 kg/ha with significant interactions between regions and varieties concerning sweet glycoside contents. Stevia offers great potential for introduction as a commercial crop producing a biological sweetener under Moroccan conditions. • Rebaudiana crops have proved to be very well adapted to the Moroccan conditions. • High dried leaf yields of stevia were detected with significant variability. • The accumulation of steviol glycosides was very important in the 4 varieties. • Biomass and steviol glycosides are influenced by Variety × environment interactions.

LC-MS metabolomics analysis of Stevia rebaudiana Bertoni leaves cultivated in Malaysia in relation to different developmental stages.

Stevia is known for its sweet taste, attributed to the presence of steviol glycosides. Although reports on the dynamic changes of steviol glycosides during development of stevia are available, the data are mainly focused on stevioside and rebaudioside A. Information concerning the comprehensive metabolite profile of stevia in relation to different developmental stages is still lacking. This study investigated the metabolite changes along the developmental stages of a local stevia cultivar. Stevia leaves were harvested at 4 different developmental stages (early vegetative, late vegetative, budding, and flowering). Samples were then subjected to LC-MS metabolomics analysis to determine the metabolite variations. A total of 55 metabolites, comprising phenolic acids, flavonoids, and terpenoids were identified by MS/MS analysis of the stevia leaf extracts, revealing a metabolite profile which was comparatively similar with those of cultivars grown in other countries. PLS-DA differentiated the early vegetative stage stevia leaf samples from those of the later stages by higher content of phenolic acids. The leaf metabolomes of the later 3 stages (late vegetative, budding, and flowering) were collectively richer in flavonoids. Meanwhile, the content of steviol glycosides is highest during the late vegetative and budding stages. The present study provided, for the first time, a general overview of the metabolite variations with regard to the different developmental stages of stevia. The information may facilitate decision making of suitable harvesting times for higher yields of steviol glycosides or a more balanced metabolite profile in terms of pharmacologically useful metabolites.

Fungal glycosyl hydrolases for sustainable plant biomass valorization: Talaromyces amestolkiae as a model fungus.

As the main decomposers and recyclers in nature, fungi secrete complex mixtures of extracellular enzymes for degradation of plant biomass, which is essential for mobilization of the organic carbon fixed by the photosynthesis in vegetal cells. Biotechnology can emulate the closed natural biological cycles, using lignocellulosic biomass as a renewable resource and lignocellulolytic fungal enzymes as catalysts to sustainably produce consumer goods. Cellulose and hemicellulose are the major polysaccharides on Earth, and the main enzymes involved in their hydrolytic depolymerization are cellulases (endoglucanases, cellobiohydrolases, and β-glucosidases) and hemicellulases (mainly endoxylanases and β-xylosidases). This work will focus on the enzymes secreted by the filamentous ascomycete Talaromyces amestolkiae and on some of their biotechnological applications. Their excellent hydrolytic activity was demonstrated by the partial degradation of xylans to prebiotic oligosaccharides by the endoxylanase XynN, or by the saccharification of lignocellulosic wastes to monosaccharides (fermentable to ethanol) either by the whole secretomes or by isolated enzymes used as supplements of commercial cocktails. However, apart from their expected hydrolytic activity, some of the β-glycosidases produced by this strain catalyze the transfer of a sugar molecule to specific aglycons by transglycosylation. As the synthesis of customized glycoconjugates is a major goal for biocatalysis, mutant variants of the β-xyloxidase BxTW1 and the ß-glucosidases BGL-1 and BGL-2 were obtained by directed mutagenesis, substantially improving the regioselective production yields of bioactive glycosides since they showed reduced or null hydrolytic activity.

IN SILICO CHARACTERIZATION OF PUTATIVE ZAT10 GENE IN Stevia rebaudiana ACCESSION MS007

Stevia rebaudiana is among recognized medicinal plants used as an artificial sweetener in food and drinks as it contains very low sugar content. It is recognized that stevia contains component steviol glycoside which contains stevioside and rebaudioside A has 50 to 100 more sweetness than sucrose. Due to this, stevia extraction of steviol glycoside is very demanded in the food and pharmaceutical industries. Research shows that stevioside levels are the highest at the time of flower bud formation and lower at the time preceding and following flower bud formation. Hence, this study aims to identify and characterize the putative gene that may involve in the flowering of local S. rebaudiana accession MS007 from the analysis of bioinformatics tools. The outcome of this study will help further in the study of the manipulation of the flowering process to increase the outcome yield of steviol glycoside. This study involves characterization of putative zinc finger ZAT10 gene by homology search by BLAST, protein domain search using InterPro, physicochemical analysis using ProtParam and TMHMM, multiple sequence alignment using MUSCLE, and phylogenetic tree construction using MEGA. The bioinformatics analysis using these programs and software manages to identify the protein domain of ZAT10 which shows the function of metal ion binding and involve in transcriptional regulation. The analysis of the phylogenetic tree also shows that ZAT10 protein may have a recent common ancestor in its own Asteraceae families such as Lactuca sativa and Heliantus annus.

Ultrasound-assisted Extraction Process of Glycosides from Stevia Rebaudiana Bertoni Leaves

Stevia Rebaudiana Bertoni leaves contain glycosides that have a sweetening power of 100 to 300 times greater than sucrose. These glycosides are increasingly used as natural sweetener, mainly to replace aspartame, in order to reduce daily caloric intake. The two major glycosides are Stevioside and Rebaudioside A, which represent about 90 % [w/w] of total Steviol. The Rebaudioside A is the most interesting since it has the advantage of not having a bitter aftertaste, unlike stevioside. In recent years, the cultivation of organic stevia is growing in the Occitanie region in France. Thus, the valorization of this production chain is of economic interest for this region. It’s known that conventional extractions to obtain these glycosides are time consuming and the extensive use of organic solvents may be harmful for human health and environment. Thus, the objective of this work was to develop a green extraction process suitable for industrial purposes, using water as solvent and ultrasound technique to obtain high yield of glycosides in the Stevia extract. The extractions are carried out in batch with recirculation and continuous assemblies at 45 °C. The effects of ultrasound power (at 20kHz), experience time/ residence time, and leaves concentration are studied. The soluble solids and stevia glycosides concentration are analyzed respectively by °Bx and HPLC. With the continuous assembly the experiments were carried out at 64 W and 144 W, which represents 50 % and 100 %, respectively, of the generator capacity. A low flowrate (or high residence time) is detrimental to the use of ultrasound, leaves sedimentation and their accumulation prevents probably the ultrasound diffusion in the medium, harming the steviol extraction. The extraction ultrasound-assisted allowed to increase in 9-10 % °Bx concentration for batch and continuous assembly, compared to extraction without ultrasound under the same conditions. Soluble species other than steviols are extracted with ultrasound. The HPLC results showed that the ultrasound favored lightly the extraction of stevioside.Key-words: continuous extraction, green extraction, sweeteners.

Engineering Thermotoga maritima β-glucosidase for improved alkyl glycosides synthesis by site-directed mutagenesis.

Alkyl glycosides are well-characterized nonionic surfactants, and can be prepared by transglycosylation reactions with retaining GH1 glycosidases being normally used for this purpose. The produced alkyl glycosides can also be hydrolyzed by the glycosidase, and hence, the yields of alkyl glycosides can be too low for industrial use. To improve the transglycosylation-to-hydrolysis ratio for a β-glucosidase from Thermotoga maritima (TmBglA) for the synthesis of alkyl glycoside, six mutants (N222F, N223C, N223Q, G224A, Y295F, and F414S) were produced. N222F, N223C, N223Q, G224A improved catalytic activity, F295Y and F414S are hydrolytically crippled with p-nitrophenol-β-d-glucopyranoside (pNPG) as substrate with an 85 and 70-fold decrease in apparent kcat, respectively; N222F shows the highest kcat/km value for pNPG. The substrate selectivity altered from pNPG to pNP-β-d-fucoside for N222F, F295Y, and F414S and from cellubiose to gentiobiose for N222F and F414S. Using pNPG (34 mM) and hexanol 80% (vol/vol), N222F, Y295F, and F414S synthesized hexyl-β-glycoside (HG) yields of 84.7%, 50.9%, and 54.1%, respectively, HG increased from 14.49 (TmBglA) to 22.8 mM (N222F) at 2 hr by 57.42%. However, this higher transglycosylation effect depended on that three mutants creates an environment more suited for hexanol in the active site pocket, and consequently suppressed its HG hydrolysis.

Optimization of amylomaltase for the synthesis of α-arbutin derivatives as tyrosinase inhibitors

α-Arbutin is widely used as a skin-whitening agent in the pharmaceutical and cosmetic industries because of its inhibitory effect on tyrosinase, an important enzyme for generating melanin pigments. Given the increasing demand for such products, we synthesized α- and β-arbutin-α-D-glycosides through transglycosylation reactions catalyzed by a recombinant amylomaltase, using tapioca starch and α- and β-arbutin as donor and acceptor molecules, respectively. The catalytic yield of products by the amylomaltase was greater with α-arbutin than with β-arbutin. The highest glycoside yield (83%) was achieved by adjusting the following six parameters: starch and α-arbutin concentration, enzyme concentration, pH, temperature, and incubation time. The glycoside products were isolated and analyzed by HPLC, and two major products were identified by mass spectrometry and nuclear magnetic resonance spectroscopy, namely, α-arbutin-α-d-glucopyranoside (α-Ab-α-G1) and α-arbutin-α-d-maltopyranoside (α-Ab-α-G2). Both α-Ab-α-G1 and α-Ab-α-G2 are more water soluble than α-arbutin. Like α-arbutin, α-Ab-α-G1 and α-Ab-α-G2 showed competitive inhibition of human tyrosinase. However, their Ki values were 0.53 and 1.40 mM, respectively, which are slightly higher than that of α-arbutin (0.25 mM). The addition of glucosyl residues to α-arbutin improved its water solubility. Therefore, α-Ab-α-G1 and α-Ab-α-G2 could be easily absorbed by the skin and used as skin-whitening agents in pharmaceutical and cosmetic industries.

The Study on the Method for Maximizing Steviol Glycoside Extract from Stevia Leaves

One of the 9 types of basic needs of Indonesian is sugar. The main resource as a sugar producer is sugar cane. However, currently with the increasing of population, the area for sugarcane plantation become limited. On the other side, Indonesia, with its wealth of natural resources, has the opportunity to use other raw materials as a source of sweetener. One of the potential sugar sources is Stevia rebaudiana. Its dry leaves contents of steviol glycosides around 5-10%. In addition, this sugar has a therapeutic function as well, since its sweetness level is quite high (200 - 300 times of sugarcane), contains vitamins, minerals and anti-oxidants. The aim of this research is to study the appropriate method that can maximize the extraction of glycoside from stevia leaves. The variables observed during the experiment were temperature generated by microwave and size of leaves. Stevioside separation process was carried out by extraction with using a microwave. Analysis of the glycoside yield was conducted using turbidity meter and colorimeter.

Phytochemical screening and estrogenic activity of total glycosides of Cistanche deserticola

AbstractOver the decades, there have been continuous efforts to enhance the quality of human life. Postmenopausal syndrome is a serious concern for the wellbeing of a woman's health. Hormonal therapy is currently the mainstay of treatment for this condition. However, this therapy could lead to estrogen abuse, leading to adverse reactions and side effects. As a result, hormonal therapy has been unsuccessful in ameliorating postmenopausal syndrome. Cistanche deserticola is a classical tonic herb in traditional Chinese medicine. It exhibits significant estrogenic activity. The main active compounds of this herb are glycosides. In a previous experiment, three important factors contributing to the total glycoside yield, acteoside yield, and estrogenic activity were identified, namely, eluent concentration, pH, and eluent volume. In this experiment, an optimal purification process was determined using a central composite design-response surface methodology to obtain glycosides from this herb. An eluent (ethanol) concentration of 85% and volume of 25 BV at a pH of 11 was found to be optimal. Twenty-one active compounds were identified by a high-performance liquid chromatography/ quadrupole time-of-flight mass spectrometry assay. This study provides valuable insights for further in-depth research evaluating the estrogenic activities of total glycosides of Cistanche deserticola.

Qualitative and Quantitative Analysis of Different Rhodiola rosea Rhizome Extracts by UHPLC-DAD-ESI-MSn

Rhodiola rosea has been used in folk medicine as ethanolic macerates for a long time. This study aims to provide a quantitative and qualitative analysis and comparison of different ethanolic Rhodiola rosea rhizome macerates (35%, 70%, and 96% v/v) and accelerated solvent extraction (ASE) extracts prepared with 85% methanol, in order to shed light on the effectivity of different extraction methods. Extract samples were analyzed by UHPLC-DAD-ESI-MSn on a ZORBAX SB-C18 column (100 × 2.1 mm, 1.8 μm) with a mobile phase consisting of water + 0.1% formic acid and acetonitrile. Qualitative analysis lead to the tentative identification of 18 compounds: Two cyanogenic glycosides (rhodiocyanoside A, lotaustralin), three phenylethanoids (salidroside, viridoside, 2-phenylethyl-vicianoside), two procyanidin and catechin derivatives (epigallocatechin-epigallocatechin gallate, epigallocatechin-3-O-gallate), five phenylpropanoids (cinnamyl alcohol, rosarin, rosavin, rosin, cinnamyl-(6’-O-β-d-xylopyranosyl)-O-β-glucopyranoside), two monoterpene alcohols (rhodioloside E, rosiridin) and four flavonols (rhodionidin, rhodiosin, rhodionin, kaempferol). Quantity was determined for salidroside, cinnamyl alcohol and its three major glycosides (rosarin, rosavin, rosin), as well as three flavonols (rhodionidin, rhodiosin, rhodionin). Methanolic ASE proved to be the superior extraction method for different substance groups. For macerates, high ethanol content increased yield and lowered hydrolysis of glycosides during extraction, but ethanolic macerates still showed low reproducibility and high fluctuations in quantity of marker compounds salidroside and rosavins, as well as flavonols. Rhodiola rosea rhizomes of wild origins seemed to underly great variability in chemical composition dependent on grow site.

Ultrafine grinding of poplar biomass: effect of particle morphology on the liquefaction of biomass for methyl glycosides and phenolics

This paper shows that mechanical ultrafine grinding of poplar wood is an efficient pretreatment approach to enhance its reactivity during liquefaction. The microstructural features and chemical properties of biomass samples with different particle morphology were studied. In particular, we found that more cellulose and hemicellulose were exposed on the outer surface of the ultrafine powder (cellular scale of plant) and the crystal lattice structure of cellulose was significantly damaged. As a result, the degree of liquefaction reached 92.03% at 180 °C using UP feedstock, largely exceeding the value (53.35%) obtained at the same temperature using PS0.25. Two groups of value-added chemicals, namely phenolics and methyl glycosides were obtained during liquefaction. At 180 °C, the yields of methyl glycosides and phenolics obtained from an UP feedstock were, respectively, 28.45% and 10.17% higher than those obtained from the PS0.25. In addition, a high degree of liquefaction (> 90%) could be obtained at a temperature 40 °C lower than the one required by PS0.25, greatly reducing the occurrence of side reactions and improving the purity of target products. Overall, the mechanical fragmentation of biomass at cellular scale is a promising pretreatment method allowing high valorization of the entire biomass.