Alkaloid Yield Research Articles

Green and sustainable recovery of polyphenols, flavonoids, alkaloids, and pigments from green tea leaves: Comparative analysis of Soxhlet, accelerated solvent, and supercritical fluid extraction techniques

The growing interest in green tea extracts for their applications in pharmaceutical, food, and cosmetic industries underscores the need for environmentally sustainable extraction methods. This study presents optimized strategies for the green recovery of bioactive compounds from Gun powder green tea leaves using Soxhlet extraction, accelerated solvent extraction, and supercritical fluid extraction techniques. By varying extraction solvents (supercritical CO2, ethanol, water, and their combinations) and temperatures (from 35 to 140 °C), high yields of polyphenols, flavonoids, alkaloids, and pigments were achieved. Key bioactive compounds extracted in significant quantities included caffeine (23.8 mass%), chlorophyll A (8.1 mg/g), chlorophyll B (0.7 mg/g), carotenoids (0.4 mg/g), epicatechin (7.7 mass%), catechin gallate (4.6 mass%), and epigallocatechin-3-gallate (30.2 mass%). The extract obtained in optimized processes demonstrated potent antioxidant activity (IC50 up to 88 μg/mL), strong antimicrobial activity (including methicillin-resistant Staphylococcus aureus- MRSA) with MIC up to 0.06 mg/mL, and selective anticancer activity against colon cancer cells. The presented findings provide a theoretical basis and technical guidance for enhancing the sustainable concentration of natural bioactive compounds, promoting their use in various industrial applications.

Effect of supercritical CO2 modified with ethanol on the extraction yield and antimicrobial activity of bioactive compounds from aerial parts of Berberis microphylla G. Fort

Calafate (Berberis microphylla G. Forts) is an endemic plant from the Patagonian area of Chile and Argentina, with a high content of bioactive compounds. In this study the effect of ethanol-modified supercritical extraction at temperatures of 40 and 60 °C, pressures of 30 and 35 MPa, and azeotropic ethanol contents in CO2 of 5 and 10% on the yield of total solids (gravimetric method), alkaloids (spectrophotometric analysis), berberine (HPLC-DAD analysis), phenolics (spectrophotometric analysis), and antimicrobial activity (disc diffusion method) of calafate aerial parts, was evaluated. The yield of total solids increased with extraction temperature, pressure, and the percentage of ethanol in CO2. Berberine yield reached a maximum of 0.0211 ± 0.46 g/kg substrate at 60 °C, 35 MPa, and using 10% ethanol. Extraction at 40 °C resulted in a higher phenolic content (1.69 ± 0.02 g GAE/kg substrate) than at 60 °C. Limited antibacterial activity was observed in all obtained extracts with ethanol-modified supercritical CO2 against Staphylococcus aureus, with no significant difference between treatments. Ethanol-modified CO2 demonstrated moderate efficiency for extracting bioactive compounds from calafate aerial parts compared with Soxhlet extraction with azeotropic ethanol.

Optimization and evaluation of biologically active compound with antibacterial and anti-inflammatory properties from peony seed meal

Peony seed meal is produced annually on a large scale in China, resulting in considerable solid residue. Unfortunately, most of this residue is discarded, thereby creating environmental pressure. However, the untapped medicinal value of peony seed meal prompted us to establish an efficient methodology for optimizing the extraction and purification of total alkaloid, followed by a detailed analysis of its biological activities. A single-factor experiment and an orthogonal test were used to identify the optimal extraction parameters. Then, further optimization was performed using the response surface methodology. The extract was enriched using D-101 macroporous adsorption resin. Subsequently, silica gel column chromatography was used for separation, and high-performance liquid chromatography was used for further separation and quantification. Meanwhile, gas chromatography–mass spectrometry (GC–MS) was used to identify alkaloid components. Finally, the antibacterial and anti-inflammatory were evaluated. The optimal extraction conditions substantially improved the yield of alkaloids. A total of 15 alkaloids were separated. GC–MS analysis revealed the presence of Sophoridine, which accounted for 91.88 % of the total alkaloid content. The antibacterial activity of the total alkaloid was tested, and the lowest inhibitory concentrations of E. coli ATCC 25922 and S. aureus ATCC 29213 were 0.04516 and 0.05645 mg/mL, respectively. Additionally, total alkaloid had an inhibitory effect on ear swelling induced by xylene and toe swelling induced by egg white, reducing by 80 % and 24 %, respectively. The current research discovered the antibacterial activity of PSM alkaloid, which has important practical significance for the research and development of new plant-derived antibacterial agents.

Genomic and Cell-Specific Regulation of Benzylisoquinoline Alkaloid Biosynthesis in Opium Poppy.

Opium poppy is a crop of great commercial value as a source of several opium alkaloids for the pharmaceutical industries including morphine, codeine, thebaine, noscapine and papaverine. Most enzymes involved in benzylisoquinoline alkaloids (BIAs) biosynthesis in opium poppy have been functionally characterized, and opium poppy currently serves as a model system to study BIA metabolism in plants. BIA biosynthesis in opium poppy involves two biosynthetic gene clusters associated respectively with the morphine and noscapine branches. Recent reports have shown that genes in the same cluster are co-expressed, suggesting they might also be co-regulated. However, the transcriptional regulation of opium poppy BIA biosynthesis is not well studied. Opium poppy BIA biosynthesis involves three cell types associated with the phloem system: companion cells, sieve elements and laticifers. The transcripts and enzymes associated with BIA biosynthesis are distributed across cell types, requiring the translocation of key enzymes and pathway intermediates between cell types. Together, these suggest that the regulation of BIA biosynthesis in opium poppy is multilayered and complex, involving biochemical, genomic, and physiological mechanisms. In this review, we highlight recent advances in genome sequencing and single cell and spatial transcriptomics with a focus on how these efforts can improve our understanding of the genomic and cell-specific regulation of BIA biosynthesis. Such knowledge is vital for opium poppy genetic improvement and metabolic engineering efforts targeting the modulation of alkaloid yield and composition.

Exogenous regulation of macronutrients promotes the accumulation of alkaloid yield in anisodus tanguticus (Maxim.) pascher

BackgroundAnisodus tanguticus (Maxim.) Pascher (A. tanguticus) is a valuable botanical for extracting tropane alkaloids, which are widely used in the pharmaceutical industry. Implementing appropriate cultivation methods can improve both the quality and yield of A. tanguticus. A two-year field experiment was conducted from 2021 to 2023 using a single-factor randomized complete block design replicated three times. The study examined the effects of different nutrient levels (nitrogen: 0, 75, 150, 225, 300, 375 kg/ha; phosphorus: 0, 600, 750, 900, 1050, 1200 kg/ha; potassium: 0, 75, 112.5, 150, 187.5, 225 kg/ha) on the growth, primary alkaloid contents, and alkaloid yield of A. tanguticus at different growth stages (S-Greening, S-Growing, S-Wilting; T-Greening, T-Growing, and T-Wilting) in both the roots and aboveground portions.ResultsOur results demonstrate that nutrient levels significantly affect the growth and alkaloid accumulation in A. tanguticus. High nitrogen levels (375 kg/ha) notably increased both root and aboveground biomass, while phosphorus had a minimal effect, especially on aboveground biomass. For alkaloid content (scopolamine, anisodamine, anisodine, atropine), a moderate nitrogen level (225 kg/ha) was most effective, followed by low potassium (75 kg/ha), with phosphorus showing a limited impact. Increased phosphorus levels led to a decrease in scopolamine content. During the T-Growing period, moderate nitrogen addition (225 kg/ha) yielded the highest alkaloid levels per unit area (205.79 kg/ha). In the T-Wilting period, low potassium (75 kg/ha) and low phosphorus (750 kg/ha) resulted in alkaloid levels of 146.91 kg/ha and 142.18 kg/ha, respectively. This indicates nitrogen has the most substantial effect on alkaloid accumulation, followed by potassium and phosphorus. The Douglas production function analysis suggests focusing on root biomass and the accumulation of scopolamine and atropine in roots to maximize alkaloid yield in A. tanguticus cultivation.ConclusionsOur findings show that the optimum harvesting period for A. tanguticus is the T-Wilting period, and that the optimal nitrogen addition is 225 kg/ha, the optimal potassium addition is 75 kg/ha, and the optimal phosphorus addition is 600 kg/ha or less.

Alkaloid Accumulation and Distribution within the Capsules of Two Opium Poppy (Papaver somniferum L.) Varieties.

The goal of this study was to clarify the role of capsule size and morphology in the alkaloid yield of poppy. In 2023, two industrial varieties from large-scale cultivation were investigated. Three classes of capsule size (large, medium, and small) and four organelles (wall, placenta, disc, and thalamus) of the seedless capsule were studied for their mass proportions and alkaloid contents. In 'Meara', large capsules had 41% lower total alkaloid levels than smaller ones. In 'Morgana', there was no difference in total alkaloids between size groups, but large capsules had higher contents of codeine and thebaine. Among the four organelles, the wall represented the largest mass in both varieties (60-67%), while the disc and the thalamus gave the lowest proportions (below 9%). In the variety 'Meara', the highest alkaloid contents appeared in the wall (2.69% d.w.), followed by the placenta, and the other two parts. 'Morgana' accumulated the highest alkaloid content (3.72% d.w.) in the placenta. Morphine follows the trend of the total content, while codeine and thebaine may differ. Accurate information on the accumulation of alkaloids in the generative organs may contribute to increasing effectiveness in target-oriented breeding and optimization of cultivation with an appropriate choice of variety.

Advancing green extraction of bioactive compounds using deep eutectic solvent-based ultrasound-assisted matrix solid-phase dispersion: Application to UHPLC-PAD analysis of alkaloids and organic acids in Coptidis rhizoma

The utilization of deep eutectic solvents (DES) in sustainable extracting and separating of phytochemicals shows promising prospect. An exceptionally fast, eco-friendly, and sustainable approach was proposed for extracting bioactive compounds from Coptidis Rhizoma based on deep eutectic solvent-based ultrasound-assisted matrix solid phase dispersion (DES-UA-MSPD). Single-factor experiments and Box-Behnken design were utilized to explore the optimal extraction conditions. The analysis indicated that the acidic DES, especially betaine-acrylic acid (Bet-Aa 1:4 mol/mol) with 50% water content, was proved to be the most effective medium for the extraction of alkaloids (magnoflorine, groenlandicine, coptisine, epiberberine, berberine and palmatine) and organic acid (chlorogenic acid). With the parameters optimized, the total maximum extraction yield of alkaloids and organic acids reached 128.83 mg g−1 applying the optimal DES, which was 1.33–5.33 folds higher than conventional extraction solvents. Additionally, through microstructure analysis using scanning electron microscopy, density functional theory , and frontier molecular orbitals theory, a deeper understanding of the extraction principle was gained, and the molecular mechanism of DES synthesis and the interactions between target compounds were systematically elucidated. The sustainable and green potential of the DES-UA-MSPD method was demonstrated through Green Analytical Procedure Indexanalysis. The overall results of this investigation revealed that the proposed technology was a highly promising and sustainable alternative for effective extraction and quantification of natural products.

The impact of nitrogen fertilization on the alkaloid content and growth traits of Datura (Datura stramonium L.)

D. stramonium is a wild plant species belonging to the nightshade family Solanaceae and grows on the edges of cotton fields, empty lands and roadsides. The plant is one of the most important economic weed plants that contain both toxic and medicinal properties. Studies have shown that the plant contains toxic tropane alkaloids such as atropine, hyoscyamine, and scopolamine. It is known that cultivation techniques have a great influence on the quality and quantity of secondary metabolites. For this reason, it is important to determine the optimal values of the agronomic factors that influence plant growth and production. This study was conducted in the experimental area of the Agricultural Faculty of Dicle University in the 2010 and 2011 growing seasons so as to evaluate the impact of nitrogen fertilizer rates (0, 50, 100 and 200 kg ha-1) on some agronomical characteristics such as fresh and dry herb yield and total alkaloid content of Datura (Datura stramonium L.). The results revealed that significant (P?0.05) differences were observed between nitrogen doses in the 2010 and 2011 growing seasons in terms of seed yield, fresh and dry herb yield and total alkaloid yield of seeds. However, seed yield changed between 545 kg ha-1 and 625 kg ha-1, fresh herb yield between 8000 and 24483 kg ha-1, dry herb yield between 2190 kg ha-1 and 5083 kg ha-1 and alkaloid content between 0.259% and 0.366%, respectively. The results showed that fresh and dry herb yields increased with increasing nitrogen doses.

Ergot alkaloids as pharmaceuticals: Status and prospects of commercial cultivation of ergot crop for natural alkaloids

Ergot is a plant disease symptom induced by a fungal pathogen of the genus Claviceps in grains of cereal crops, wherein the ergot alkaloids are produced in the cereal grains which are transformed into ergot sclerotia. The natural occurrence of ergot grains in cereal crops is dependent on the environmental factors conducive to ergot development. Under natural fungal infection, the ergot percent varies from 1.2 to 3.3 in the infected crops which hamper the yield or recovery of natural ergot alkaloids. Ergot alkaloids are specific pharmaceutical alkaloids used to treat certain ailments like migraines, induction of childbirth, and the control of postpartum bleeding in humans. Ergot sclerotia contain about 0.15% to 0.5% alkaloids, with medicinally useful compounds. Annual world production of ergot alkaloids has been estimated at 5,000-8,000 kg of all ergopeptines (peptide ergot alkaloids) and 10,000-15,000 kg of lysergic acid, the latter being mainly used in the manufacture of semisynthetic derivatives. The greater part of this production occurs as a result of fermentation (around 60%) while field cultivation of triticale (a hybrid of wheat and rye) accounts for the balance. This is because the artificial cultivation of ergot sclerotia on a host crop plant is lacking as a business module. Due to the low recovery of ergot grains and ergot alkaloids under natural crop production conditions, commercial cultivation for ergot grains is discussed in this paper.

Fungal Elicitation Enhances Vincristine and Vinblastine Yield in the Embryogenic Tissues of Catharanthus roseus.

Fungal elicitation could improve the secondary metabolite contents of in vitro cultures. Herein, we report the effect of Fusarium oxysporum on vinblastine and vincristine alkaloid yields in Catharanthus roseus embryos. The study revealed increased yields of vinblastine and vincristine in Catharanthus tissues. Different concentrations, i.e., 0.05% (T1), 0.15% (T2), 0.25% (T3), and 0.35% (T4), of an F. oxysporum extract were applied to a solid MS medium in addition to a control (T0). Embryogenic calli were formed from the hypocotyl explants of germinating seedlings, and the tissues were exposed to Fusarium extract elicitation. The administration of the F. oxysporum extract improved the growth of the callus biomass, which later differentiated into embryos, and the maximum induction of somatic embryos was noted T2 concentration (102.69/callus mass). A biochemical analysis revealed extra accumulations of sugar, protein, and proline in the fungus-elicitated cultivating tissues. The somatic embryos germinated into plantlets on full-strength MS medium supplemented with 2.24 µM of BA. The germination rate of the embryos and the shoot and root lengths of the embryos were high at low doses of the Fusarium treatment. The yields of vinblastine and vincristine were measured in different treated tissues via high-pressure thin-layer chromatography (HPTLC). The yield of vinblastine was high in mature (45-day old) embryos (1.229 µg g-1 dry weight), which were further enriched (1.267 µg g-1 dry weight) via the F. oxysporum-elicitated treatment, especially at the T2 concentration. Compared to vinblastine, the vincristine content was low, with a maximum of 0.307 µg g-1 dry weight following the addition of the F. oxysporum treatment. The highest and increased yields of vinblastine and vincristine, 7.88 and 15.50%, were noted in F. oxysporum-amended tissues. The maturated and germinating somatic embryos had high levels of SOD activity, and upon the addition of the fungal extracts, the enzyme's activity was further elevated, indicating that the tissues experienced cellular stress which yielded increased levels of vinblastine and vincristine following the T2/T1 treatments. The improvement in the yields of these alkaloids could augment cancer healthcare treatments, making them easy, accessible, and inexpensive.

Modified physiology of burley tobacco plants genetically engineered to express Yb1, a functional EGY enzyme.

Transgenic overexpression of a NtEGY2 gene restores normal green color of burley tobacco plants, but does not increase nitrogen utilization efficiency beyond that exhibited by wild-type individuals. Nitrogen physiology is important in tobacco because of its role in generation of leaf yield and accumulation of nitrogen-containing alkaloids that can react with nitrosating agents in the formation of carcinogenic tobacco-specific nitrosamines. Cultivars of the burley tobacco market class are homozygous for deleterious mutant alleles at the duplicate Yb1 and Yb2 loci which have previously been associated with decreased nitrogen use and utilization efficiency; increased leaf nitrate, total nitrogen, and alkaloid levels; and reduced yields. How mutant alleles at these two loci affect these traits is not well understood. Recent characterization of the Yb1 and Yb2 genes (homologs of Arabidopsis EGY1 gene) enabled overexpression of the wild-type Yb1 allele in yb1yb1yb2yb2 plants to determine if observed unfavorable effects were due to linkage or pleiotropy, and to determine if overexpression could lead to beneficial modifications in any of these traits in transgenic plants relative to naturally-occurring wild-type genotypes. Yb1 overexpression was found to confer an agronomic benefit to yb1yb1yb2yb2 genotypes but no advantage to wild-type genotypes. RNA-Seq was used to carry out a comparative transcriptome analysis of genetically engineered and wild-type nearly isogenic lines (NILs) to gain insight on metabolic pathways affecting carbon and nitrogen metabolism that might be altered as the result of genetic variability at the Yb1 and Yb2 loci. Results indicate that complex changes in the transcriptome of tobacco can be manifested by altered expression of Yb1.

The effectiveness of the complex application of humates and micronutrient fertilizers on the <i>Macleaya x kevensis</i> Turill. and <i>Macleaya cordata</i> (Willd.) R.Br.

Relevance. In the arsenal of agents with antibacterial activity, a significant place belongs to preparations based on the raw materials of two types of Macleia - Macleaya x kevensis Turill. and Macleaya cordata (Willd.) R.Br. used both in medical and veterinary practice. It is possible to provide the domestic pharmaceutical industry with these medicinal raw materials in full through the development of methods for increasing yields and adapting Maclea to unstable environmental weather conditions.Material and methods. Experiments to study the effect of the use of humates and microfertilizers on these indicators were laid in the fields of the North Caucasus branch of VILAR in 2019-2021. We studied the morphological and economically valuable traits of two species of Maclea, evaluated the growth rates of plants, the yield of raw materials, the content of alkaloids and their collection per hectare under optimal and dry weather conditions.Results. Differences between the two types of Maclea are established in terms of morphological and economically valuable traits. Maclea heart-shaped palmate-lobed leaves are light green in color, the roots are vertical, round-cylindrical, reaching a depth of 50 cm or more, plant height is 300-350 cm. at a depth of 25-30 cm, plant height 200-250 cm. % versus 0.162-0.164% for the heart-shaped Maclea. The dependence of the growth, development and productivity of two types of Maclea on meteorological conditions has been established. Under the conditions of insufficient water supply and high temperatures, the loss of yield in the first year of vegetation in Macleaya cordata is 14%, in the second year - 6%, in Macleaya x kevensis - 21 and 12%, respectively. Foliar treatments with the Normat L complex with Ferovit in the first year of vegetation contributed to a decrease in crop losses and an increase in the yield of alkaloids per 1 hectare in both types of makley, in the second year, with these treatments, an increase in yield by 7-11% was observed, the collection of alkaloids per hectare increased by 14- 18%.

Optimizing the Production of Antioxidant and Antibacterial Alkaloids from Macleaya cordata by Subcritical Water Extraction Technology.

In this work, the subcritical water extraction technology was used to extract alkaloids from Macleaya cordata, and the effects of extraction temperature and time on its yield were investigated to find the best extraction conditions. Moreover, the antioxidant capacity and antibacterial activity of Macleaya cordata extract were studied. Furthermore, through the single-factor method, it was found that properly increasing the extraction temperature and prolonging the extraction time was conducive to increasing alkaloid yield. Still, a considerable amount of alkaloids might be decomposed by heat, resulting in a decrease in their yield. The results showed that the optimal extraction temperature of alkaloids from Macleaya cordata with subcritical water is 190 °C, the time is 45 min, and the corresponding maximum yield is 35.19±0.12 mg/g (sanguinarine equivalent in raw materials). In addition, the antioxidation and bacteriostasis abilities of subcritical water extract are better than those of traditional hot water extract, indicating that it is a feasible method to extract alkaloids from Macleaya cordata with subcritical water.

Long-Term Impact of N, P, K Fertilizers in Different Rates on Yield and Quality of Anisodus tanguticus (Maxinowicz) Pascher.

Anisodus tanguticus (Maxinowicz) Pascher (Solanaceae) is a traditional Chinese herb that is widely used in folklore and clinical practice. In recent years, wild populations have been severely impacted to the point of extinction due to over-harvesting and reclamation. Therefore, artificial cultivation is important to relieve the pressure of market demand and protect wild plant resources. Using a "3414" fertilization design, i.e., 3 factors (N, P, and K), 4 levels, and 14 fertilization treatments, with 3 replicates and a total of 42 experimental plots, A. tanguticus was harvested in October 2020, June 2021, August 2021, and October 2021, and the yield and alkaloid content were determined. The study aimed to provide a theoretical basis and technical reference for the standardization of A. tanguticus cultivation. Biomass accumulation and alkaloid content showed a trend of increasing and then decreasing with the application of nitrogen, phosphorus, and potassium, and the biomass accumulation was the highest at the application levels of nitrogen and phosphorus in T6 and T9 and at the application levels of medium and low potassium. The alkaloid content showed an increasing trend between October of the first year and June of the second year and a decreasing trend in the second year with the increase in the harvesting period. Yield and alkaloid yield showed a decreasing trend between October of the first year and June of the second year and an increasing trend in the second year with the increase in the harvesting period. The recommended application rates are 225-300 kg/ha2 for nitrogen, 850-960 kg/ha2 for phosphorus, and 65-85 kg/ha2 for potassium.

Vinca alkaloids as a potential cancer therapeutics: recent update and future challenges.

Vinca alkaloids including vincristine, vinblastine, vindesine, and vinflunine are chemotherapeutic compounds commonly used to treat various cancers. Vinca alkaloids are one of the first microtubule-targeting agents to be produced and certified for the treatment of hematological and lymphatic neoplasms. Microtubule targeting agents like vincristine and vinblastine work by disrupting microtubule dynamics, causing mitotic arrest and cell death. The key issues facing vinca alkaloids applications include establishing an environment-friendly production technique based on microorganisms, as well as increasing bioavailability without causing harm to patient's health. The low yield of these vinca alkaloids from the plant and the difficulty of meeting their huge colossal demand around the globe prompted researchers to create a variety of approaches. Endophytes could thus be selected to produce beneficial secondary metabolites required for the biosynthesis of vinca alkaloids. This review covers the significant aspects of these vital drugs, from their discovery to the present day, in a concise manner. In addition, we emphasize the major hurdles that must be overcome in the coming years to improve vinca alkaloid's effectiveness.

Potentiating Biosynthesis of Alkaloids and Polyphenolic Substances in Catharanthus roseus Plant Using ĸ-Carrageenan.

Catharanthus roseus is a medicinal plant that produces indole alkaloids, which are utilized in anticancer therapy. Vinblastine and vincristine, two commercially important antineoplastic alkaloids, are mostly found in the leaves of Catharanthus roseus. ĸ-carrageenan has been proven as plant growth promoting substance for a number of medicinal and agricultural plants. Considering the importance of ĸ-carrageenan as a promoter of plant growth and phytochemical constituents, especially alkaloids production in Catharanthus roseus, an experiment was carried out to explore the effect of ĸ-carrageenan on the plant growth, phytochemicals content, pigments content, and production of antitumor alkaloids in Catharanthus roseus after planting. Foliar application of ĸ-carrageenan (at 0, 400, 600 and 800 ppm) significantly improved the performance of Catharanthus roseus. Phytochemical analysis involved determining the amount of total phenolics (TP), flavonoids (F), free amino acids (FAA), alkaloids (TAC) and pigments contents by spectrophotometer, minerals by ICP, amino acids, phenolic compounds and alkaloids (Vincamine, Catharanthine, Vincracine (Vincristine), and vinblastine) analysis uses HPLC. The results indicated that all examined ĸ-carrageenan treatments led to a significant (p ≤ 0.05) increase in growth parameters compared to the untreated plants. Phytochemical examination indicates that the spray of ĸ-carrageenan at 800 mg L-1 increased the yield of alkaloids (Vincamine, Catharanthine and Vincracine (Vincristine)) by 41.85 μg/g DW, total phenolic compounds by 3948.6 μg gallic/g FW, the content of flavonoids 951.3 μg quercetin /g FW and carotenoids content 32.97 mg/g FW as compared to the control. An amount of 400 ppm ĸ-carrageenan treatment gave the best contents of FAA, Chl a, Chl b and anthocyanin. The element content of K, Ca, Cu, Zn and Se increased by treatments. Amino acids constituents and phenolics compounds contents were altered by ĸ-carrageenan.

Extraction of bioactive compounds from Leptocarpha rivularis stems by three-stage sequential supercritical extraction in fixed bed extractor using CO2 and ethanol-modified CO2

Sequential supercritical extraction experiments were carried out in three stages each using CO2 and ethanol-modified-CO2, to improve the extraction yield of bioactive compounds from L. rivularis stems. Four experiments were carried out, each in three stages, combining different levels of temperature (40 or 60 °C) and pressure (20–50 MPa). The increase in pressure and use of a cosolvent increased the total yield of extract and target compounds compared to one-stage extraction. The highest extraction yields of extract (6.29 g/kg d.s.), terpenes (699.9 mg/kg d.s.), flavonoids (741.9 mg/kg d.s.), and alkaloids (6.22 mg/kg d.s.) were obtained in Experiment 4. Sequential extraction of compounds was superior to one-stage extraction using CO2, but inferior when using ethanol-modified CO2. Both sequential and one-stage cumulative extraction curves were modeled, and the effective diffusivity coefficients ranged between 1.51 and 63.3 × 10–13 m2/s, being highest in Stage 3 where the extraction yield was greatest.

An efficient and green separation method of total alkaloids by resorcinol-formaldehyde aerogel during extraction of Coptis chinensis

Alkaloids are the most medicinally valuable ingredients in plant crop Coptis chinensis (C. chinensis). However, the separation of these small-molecule compounds is challenging because C. chinensis also contains a lot of impurities such as proteins and saccharides. Adsorption separation stands out in the field of biological separation by virtue of its efficiency and greenness. Here, this paper aimed to selectively separate the total alkaloids during extraction of C. chinensis by resorcinol-formaldehyde (RF) aerogel based on electrostatic interaction and size-sieving effect. First, RF aerogels with different surface area (40.6–674.9 m2/g) and pore size (2–25 nm approximately) were synthesized by adjusting the ratio of catalyst (C). The results of static adsorption showed that the optimum alkaloids selective separation was achieved at R/C of 10/1: alkaloids adsorption capacity (Qe), protein retention ratio (Pr), saccharides retention ratio (Sr) and the coefficient of selectivity were 487.93 mg/g, 87.40 %, 95.90 % and 2.23, respectively. Methanol containing 1 % hydrochloric acid was considered as the most suitable eluent with the desorption efficiency of 95.88 %. In addition, the adsorption process conformed to pseudo-second-order kinetics, intra-particle diffusion and Langmuir isotherm models, and was a spontaneous endothermic process. It was found from the dynamic adsorption experiment that the dynamic adsorption capacity was 497.81 mg/g, and the purity of total alkaloids increased from 39.19 % to 90.22 %. Compared with resin adsorption and salt precipitation method, RF aerogel separation could more efficiently separate the alkaloids from C. chinensis (the total alkaloids yield of 57.40 mg/g C. chinensis). In addition, the alkaloids separated by RF aerogel had better antioxidant and antibacterial activities than that separated by salt precipitation method. In summary, RF aerogel separation was potential as an efficient and green method for the separation of total alkaloids from C. chinensis.

Optimization of extraction technology of alkaloids in lotus leaf based on BP neural network

In order to overcome the bad precision of fitted error, lower accuracy optimization results and other flaws, when extraction technology of the lotus leaf alkaloids was optimized by response surface method or regression analysis method, a linear constraint optimization method based on BP neural network is proposed. The testing program of three factors, three level was designed, which selected the hydrochloric acid mass fraction, ultrasound time, liquid-solid ratio as experimental factors. Taking the experiment data as training sample, the BP neural network model of the lotus leaf alkaloid yield and the influencing factors was obtained, and it was optimized by the proposed optimization method. The optimal parameter combination of extraction technology for lotus leaf alkaloid was obtained as follows: extraction temperature 60 °C, ultrasonic power 500W, hydrochloric acid mass fraction 0.3%, ultrasonic time 43 min, liquid-solid ratio 27, the yield of lotus leaf alkaloids under this process condition is 4.26 mg/g. It better than the best extraction technology obtained by response surface method. The obtained results is used for verification experiment, the verification results shown that the method has high fitting accuracy and stable optimization results, which optimize the extraction technology for lotus leaf alkaloid.

Determination of 7 Kinds of Alkaloids in Semen Nelumbinis and Its Products by HPLC

Objective: To establish a method for the simultaneous determination of seven alkaloids in Semen Nelumbinis and its products, the extraction technology and HPLC method were optimized by the single factor experiment. Methods: Firstly, the samples were extracted ultrasonically with 1% formic acid ethanol and purified by PXC SPE column. Then, the extracts and the purified liquid were taken after concentration with nitrogen for quantitative analysis of seven alkaloids by HPLC method. Next, the contents of alkaloids in five samples were determined. Results: The method was fully validated and the result showed that seven kinds of alkaloids had good linear relation in the corresponding range of mass concentration, r2 > 0.999, where the detection limit was 0.5–1.5 mg/kg, the quantification limit was 1.25–4.5 mg/kg, the recovery was 83.33–116.04%, and the RSD of detection method was 1.06–5.25% (n = 7). In five samples, the contents of Lotusine and Neferine were the highest, Berberine Hydrochloride was not detected. Conclusion: This method is simple, sensitive, accurate and reproducible, and it can realize the quantitative analysis and chemical separation of seven kinds of common alkaloids in Semen Nelumbinis and its products and provide a theoretical method for the simultaneous determination of alkaloids. The extraction yields of alkaloids in Semen Nelumbinis can be increased through the extraction process, which is optimized by a single factor experiment.