Infrared assisted extraction of bioactive compounds from plant materials: Current research and future prospect

Research trends in functionalized Fe3O4 composites based on affinity recognition systems for targeted extraction of natural products

In recent years, target-specific affinity recognition systems based on Fe3O4-based composites have proven to be an effective method for screening natural products. Herbal medicines contain a wide range of natural products and are considered to be a major source for the development of novel drugs. However, the process of isolating and obtaining these bioactive components for the production of novel drugs is complex. Meanwhile, the complexity and diversity of herbal constituents have posed a great challenge to the screening studies of herbal active ingredients. Currently, traditional extraction and screening studies of active ingredients in herbal medicine include extraction and chromatographic separation technology development, serum medicinal chemistry, metabolomics and computerized virtual screening. In order to achieve integrated targeting of Fe3O4 for extraction and separation of natural products from herbs, various Fe3O4-based composites need to be synthesized so that the composites can be further functionalized and modified. Composites such as Fe3O4@SiO2, Fe3O4-based magnetic graphene oxide and Fe3O4-based magnetic carbon nanotubes were used to achieve targeted extraction and isolation of natural products from herbal medicines. The main extraction techniques involved based on these Fe3O4-based composites are molecularly imprinted techniques, immobilized ligand fishing techniques, and cell membrane-coated bionanotechnology methods. This article will present recent advances in the synthesis and modification of Fe3O4 composites and their applications for the extraction of natural products in conjunction with molecular imprinting, immobilization-targeted fishing, and cell-membrane-coated biomimetic techniques, as well as the future goals and challenges of functionalized modification of Fe3O4 composites for the targeted extraction of natural products, like protein overexpression modification, doping of fluorescent substances and genetic engineering development. A deeper understanding of the multi-level, multidisciplinary, and applied studies in materials science and phytochemistry will be provided by this article.

Extraction and Biological Activity of Lignanoids from Magnolia officinalis Rehder & E.H.Wilson Residual Waste Biomass Using Deep Eutectic Solvents

Lignanoids are an active ingredient exerting powerful antioxidant and anti-inflammatory effects in the treatment of many diseases. In order to improve the efficiency of the resource utilization of traditional Chinese medicine waste, Magnolia officinalis Rehder & E.H.Wilson residue (MOR) waste biomass was used as raw material in this study, and a series of deep eutectic solvents (ChUre, ChAce, ChPro, ChCit, ChOxa, ChMal, ChLac, ChLev, ChGly and ChEG) were selected to evaluate the extraction efficiency of lignanoids from MORs. The results showed that the best conditions for lignanoid extraction were a liquid-solid ratio of 40.50 mL/g, an HBD-HBA ratio of 2.06, a water percentage of 29.3%, an extract temperature of 337.65 K, and a time of 107 min. Under these conditions, the maximum lignanoid amount was 39.18 mg/g. In addition, the kinetics of the extraction process were investigated by mathematic modeling. In our antioxidant activity study, high antioxidant activity of the lignanoid extract was shown in scavenging four different types of free radicals (DPPH, ·OH, ABTS, and superoxide anions). At a concentration of 3 mg/mL, the total antioxidant capacity of the lignanoid extract was 1.795 U/mL, which was equal to 0.12 mg/mL of Vc solution. Furthermore, the antibacterial activity study found that the lignanoid extract exhibited good antibacterial effects against six tested pathogens. Among them, Staphylococcus aureus exerted the strongest antibacterial activity. Eventually, the correlation of the lignanoid extract with the biological activity and physicochemical properties of DESs is described using a heatmap, along with the evaluation of the in vitro hypoglycemic, in vitro hypolipidemic, immunomodulatory, and anti-inflammatory activity of the lignanoid extract. These findings can provide a theoretical foundation for the extraction of high-value components from waste biomass by deep eutectic solvents, as well as highlighting its specific significance in natural product development and utilization.

Dynamic high pressure microfluidization-assisted extraction of plant active ingredients: a novel approach

The extraction method has a great influence on the yield, quality, chemical structure, and biological activities of active ingredients. Safe and efficient extraction of active ingredients is one of the important problems facing the food and pharmaceutical industry. As a pretreatment approach for the extraction of active ingredients, dynamic high pressure microfluidization (DHPM) is a promising strategy that can not only effectively increase the yield of active ingredients but also strengthen the bioactivities of active ingredients, and take the advantages of mild operating temperature and environmental friendliness. In this review, the research progress of DHPM-assisted extraction of active ingredients from plant materials in recent ten years is overviewed. The DHPM equipment, strengthening mechanism, operating procedure, critical factors and application of DHPM-assisted extraction are introduced in detail, together with the advantages and disadvantages. Furthermore, its future development trend is discussed at the end. DHPM-assisted extraction is considered as the ideal technique of better homogenization effects, less solvent consumption, more reliable operation, and so on, making it a promising method to acquire active ingredients efficiently. Therefore, this technique is worthy of further theoretical research and experimental operation.

Activity and potential mechanisms of action of persimmon tannins according to their structures: A review

One distinguishing feature of the persimmon, that differentiates it from other fruits, is its high proanthocyanidins content, known as persimmon tannin (PT). Despite the poor absorption of PT in the small intestine, results from animal studies demonstrate that PT has many health benefits. Our goal in this review is to summarize the literature that elucidates the relationship between PT structure and activity. In addition, we also summarize the potential mechanisms underlying the health benefits that result from PT consumption; this includes the hypolipidemic, hypoglycemic, antioxidant, anti-inflammatory, antiradiation, antibacterial and antiviral, detoxification effects on snake venom, and the absorption of heavy metals and dyes. Studies show that PT is a structurally distinct proanthocyanidins that exhibits a high degree of polymerization. It is galloylation-rich and possesses unique A-type interflavan linkages in addition to the more common B-type interflavan bonds. Thus, PT is converted into oligomeric proanthocyanidins by depolymerization strategies, including the nucleophilic substitution reaction, acid hydrolysis, and hydrogenolysis. In addition, multiple health benefits exerted by PT mainly involve the inactivation of lipogenic and intracellular inflammatory signaling pathways, activation of the fatty acid oxidation signaling pathway, regulation of gut microbiota, and highly absorptive properties.

Current status and future challenges in extraction, purification and identification of Cepharanthine (a potential drug against COVID-19)

With the outbreak of the new coronavirus disease 2019 (COVID-19), the rapid spread of the virus has brought huge economic losses and life threats to the world. So far, we have entered the third year of the epidemic and there is an urgent need to provide more anti-viral treatment along with vaccination. Recent studies have confirmed that Cepharanthine (CEP) has strong antiviral efficacy, which is a potential drug against COVID-19. As a natural active alkaloid, the development of CEP-incorporated products is dependent on the extraction, purification and identification of CEP. This review gives a brief introduction of CEP, including its origin and classification, and its conventional and novel extraction techniques. In addition, the purification and identification techniques are summarized. In the last, the future research directions are proposed. It can be found from this review that the extraction from plants is still the main way to obtain CEP, and it is necessary to use innovative techniques and their hybrid extractions to extract CEP. More efficient extraction and purification techniques should be used to extract CEP in the future. This review provides a basis for the development of novel extraction and purification techniques and industrial utilization of CEP.

Optimized infrared-assisted extraction to obtain total lipid from microalgae Scenedesmus obliquus: a green approach

Microalgae oil has great potential to address the growing energy demand and dependence on fossil fuels. However, the multilayered cell walls of microalgae hinder efficient extraction and enhanced lipid recovery. In this study, we develop a novel protocol based on near infrared-assisted extraction (NIRAE) technology to extract efficiently total lipids from Scenedesmus obliquus. Under a greener solvent extraction approach, the effect of nine non-polar/polar solvent systems in various ratios on lipid yield was tested, and the results were compared with Soxhlet, Folch, and Bligh–Dyer methods. The highest oil yields were NIRAE 15.43%, and Soxhlet 22.24%, using AcoEt/MeOH (1:2 v/v). For Folch and Bligh–Dyer, 9.11 and 10%, respectively. The optimized NIRAE conditions obtained using response surface methodology (RSM): 43.8 min, solvent/biomass 129.90:1 (m/v), and AcOEt/MeOH 0.57:2.43 (v/v) increased the oil yield significantly to 24.20%. In contrast to conventional methods, the overall optimized NIRAE process satisfied the requirements of a green extraction because of the simple and safe operation, less solvent toxicity, lower extraction time, and solvent and energy consumption.

Steam explosion pretreatment to enhance extraction of active ingredients: current progress and future prospects

The active ingredients extracted from plant materials play an important role in human life and health, and the extraction is a critical step in the preparation of them. It is necessary to develop a sustainable and green extraction. Steam explosion pretreatment enhanced extraction is a higher efficiency, lower equipment investment, less hazardous chemicals and environment-friendly technique, which has been widely used to extract active ingredients from various plant materials. In this paper, current progress and future prospects of steam explosion pretreatment enhanced extraction are overviewed. The equipment, operating steps, strengthening mechanism, critical process factors are comprehensively introduced. Furthermore, recent applications and comparisons with other techniques are discussed in depth. Finally, the future development trends are prospected. The current results show that steam explosion pretreatment enhanced extraction has the advantage of high efficiency. Moreover, steam explosion is simple in equipment, and easy to operate. In conclusion, steam explosion pretreatment can be effectively used to enhance the extraction of active ingredients from plant materials.

Optimization of Polyphenols’ Recovery from Purple Corn Cobs Assisted by Infrared Technology and Use of Extracted Anthocyanins as a Natural Colorant in Pickled Turnip

An ecofriendly extraction technology using infrared (IR) irradiation Ired-Irrad^® was applied to purple corn cobs to enhance polyphenol recovery for the first time. The IR extraction efficiency was compared to that of the water bath (WB) method. Response surface methodology (RSM) using a central composite design was conducted to determine the effect of the experimental conditions (extraction time and treatment temperature) and their interactions on the total polyphenol and anthocyanin yields. Optimal extraction of total phenolic compounds (37 mg GAE/g DM) and total monomeric anthocyanins (14 mg C3G/g DM) were obtained at 63 °C for 77 min using IR as an extraction technique and water as a solvent. HPLC revealed that the recovery of peonidin 3-O-glucoside and cyanidin 3-O-glucoside was enhanced by 26% and 34%, respectively, when using IR. Finally, purple corn cobs’ spray-dried extract was proven to be an important natural colorant of pickled turnip. It offers great potential for use as a healthy alternative to the carcinogenic rhodamine B synthetic dye, which was banned.

Performance of Thermoplastic Extrusion, Germination, Fermentation, and Hydrolysis Techniques on Phenolic Compounds in Cereals and Pseudocereals

Bioactive compounds, such as phenolic compounds, are phytochemicals found in significant amounts in cereals and pseudocereals and are usually evaluated by spectrophotometric (UV-VIS), HPLC, and LC-MS techniques. However, their bioavailability in grains is quite limited. This restriction on bioavailability and bioaccessibility occurs because they are in conjugated polymeric forms. Additionally, they can be linked through chemical esterification and etherification to macro components. Techniques such as thermoplastic extrusion, germination, fermentation, and hydrolysis have been widely studied to release phenolic compounds in favor of their bioavailability and bioaccessibility, minimizing the loss of these thermosensitive components during processing. The increased availability of phenolic compounds increases the antioxidant capacity and favor their documented health promoting.

Deep Eutectic Solvent as Green Solvent in Extraction of Biological Macromolecules: A Review

Greater awareness of environmental sustainability has driven many industries to transition from using synthetic organic solvents to greener solvents in their manufacturing. Deep eutectic solvents (DESs) have emerged as a highly promising category of green solvents with well-demonstrated and wide-ranging applications, including their use as a solvent in extraction of small-molecule bioactive compounds for food and pharmaceutical applications. The use of DES as an extraction solvent of biological macromolecules, on the other hand, has not been as extensively studied. Thereby, the feasibility of employing DES for biomacromolecule extraction has not been well elucidated. To bridge this gap, this review provides an overview of DES with an emphasis on its unique physicochemical properties that make it an attractive green solvent (e.g., non-toxicity, biodegradability, ease of preparation, renewable, tailorable properties). Recent advances in DES extraction of three classes of biomacromolecules-i.e., proteins, carbohydrates, and lipids-were discussed and future research needs were identified. The importance of DES's properties-particularly its viscosity, polarity, molar ratio of DES components, and water addition-on the DES extraction's performance were discussed. Not unlike the findings from DES extraction of bioactive small molecules, DES extraction of biomacromolecules was concluded to be generally superior to extraction using synthetic organic solvents.