Subcritical water extraction of bioactive compounds from Radix Puerariae and optimization study using response surface methodology

Exploring kudzu: Extraction, quantification, and health impacts of bioactive compounds

Kudzu (Pueraria species) is a perennial plant within the Fabaceae family, native to China, Japan, and India. It is known for its therapeutic properties, mainly due to its high content of isoflavones, including puerarin, daidzein, daidzin, genistein, and genistin. These isoflavones are found throughout the plant and are important in developing pharmaceutical drugs. This review comprehensively analyzes naturally occurring isoflavones in Kudzu, focusing on advanced and green techniques for their extraction, purification, and identification. Additionally, it highlights their health benefits and the growing demand in the global food and pharmaceutical industries. Due to their superior efficiency, scalability, and cost-effectiveness, contemporary eco-friendly extraction methods like ultrasound, microwave, enzyme-assisted, and supercritical fluid extraction are gaining prominence in this endeavor. They are crucial in optimizing the extraction process, driving innovation within industries, and harnessing natural sources, ultimately boosting global economies. Scientific studies confirm that Kudzu isoflavones have various anti-diabetic, neuroprotective, anti-cancer, antioxidant, alcohol detoxification, and cardiovascular protective effects. This review encourages further exploration of Kudzu isoflavones as a nutritional food source. It also highlights advancements in extraction methods within pharmaceuticals and natural products, underscoring the superiority of modern techniques over conventional ones. Additionally, critical analysis of the trends, limitations, and scope of Kudzu-extracted isoflavones for novel food applications can further advance scientific understanding.

Extraction, purification, structural characterization, biological activity, mechanism of action and application of polysaccharides from Ganoderma lucidum: A review

Ganoderma lucidum is a traditional tonic medicine in China, known as the "fairy grass" and "spiritual grass". It contains various chemical components, such as polysaccharides, triterpenoids, alkaloids, nucleosides, sterols, and acid compounds, which have the effects of tonifying qi and calming the mind, stopping cough and asthma, and are used to treat restlessness, lung deficiency cough and asthma, fatigue and shortness of breath, and lack of appetite. Ganoderma lucidum polysaccharides (GLPs) are one of the main bioactive ingredients and are widely used in traditional Chinese medicine and traditional medicine fields. They have shown good medicinal value in enhancing immunity, inhibiting tumor cell growth, delaying aging, lowering blood sugar, lowering blood lipids, protecting the heart, anti-radiation, anti-fatigue, and other aspects. This article reviews the research progress on the extraction and purification, structural characteristics, pharmacological activity, and mechanisms of GLPs, as well as their applications in industries such as medicine, food, and daily chemical products. The aim is to provide theoretical basis for the treatment of traditional Chinese medicine compound preparations and lay the foundation for the potential value development of Ganoderma lucidum products.

Recent advances in pressurized hot water extraction/modification of polysaccharides: Structure, physicochemical properties, bioactivities, and applications

Pressurized hot water, as a green and efficient physical treatment technology, has been widely utilized for the extraction and modification of polysaccharides, with the objective of enhancing the physicochemical properties and biological activities of polysaccharides applied in food systems. This article reviews the recent advances regarding the effects of pressurized hot water treatment (extraction and modification) on polysaccharide extraction rates, structure, physicochemical properties, and bioactivities. The potential modes and mechanisms of polysaccharides subjected to pressurized hot water treatment and the relevant applications of these treated polysaccharides are also thoroughly discussed. Finally, the challenges that it may encounter in commercial applications are analyzed, and the future trends in this field are envisioned. This article will be of great value for the scientific elucidation of polysaccharides treated with pressurized hot water and their potential food applications.

Subcritical Water Extraction of Phenolic Compounds from Vaccinium Dunalianum Wight Leaves and Their Antioxidant and Tyrosinase Inhibitory Activities in Vitro

Subcritical water extraction was used to extract bioactive phenolic compounds from Vaccinium dunalianum Wight leaves. The optimal extraction conditions were determined as an extraction temperature of 150 °C, an extraction time of 40 min, and a liquid-solid ratio of 35 : 1 mL/g. The total phenolic content reached 21.35 mg gallic acid /g, which was 16 % higher than that by hot water extraction. The subcritical water extraction extract exhibited strong scavenging activity of DPPH free radical and ABTS⁺ free radical, as well as significant tyrosinase inhibitory activity. The study suggests that subcritical water extraction can alter the composition of the extracts, leading to the production of various phenolic compounds, effective antioxidants, and tyrosinase inhibitors from Vaccinium dulciana Wight leaves. These findings confirm the potential of Vaccinium dunalianum Wight as a natural antioxidant molecule source for the medicine and food industries, and for the therapy of skin pigmentation disorders.

Research Progress on the Mechanisms of Polysaccharides against Gastric Cancer

Gastric cancer is a common type of cancer that poses a serious threat to human health. Polysaccharides are important functional phytochemicals, and research shows that polysaccharides have good anti-gastric cancer effects. We collated all relevant literature published from 2000 to 2020 and found that more than 60 natural polysaccharides demonstrate anti-gastric cancer activity. At the present, the sources of these polysaccharides include fungi, algae, tea, Astragalus membranaceus, Caulis Dendrobii, and other foods and Chinese herbal medicines. By regulating various signaling pathways, including the PI3K/AKT, MAPK, Fas/FasL, Wnt/β-catenin, IGF-IR, and TGF-β signaling pathways, polysaccharides induce gastric cancer cell apoptosis, cause cell cycle arrest, and inhibit migration and invasion. In addition, polysaccharides can enhance the immune system and killing activity of immune cells in gastric cancer patients and rats. This comprehensive review covers the extraction, purification, structural characterization, and mechanism of plant and fungal polysaccharides against gastric cancer. We hope this review is helpful for researchers to design, research, and develop plant and fungal polysaccharides.

Extraction of Polysaccharide from Dendrobium nobile Lindl. by Subcritical Water Extraction

Subcritical water extraction (SWE) uses hot compressed water as an effective solvent for both polar and nonpolar compounds and has been developed as an environmentally benign extraction technology for natural materials. Polysaccharides as one of the main ingredients in Dendrobium plants showed obvious biological activity. Thus, SWE of polysaccharides obtained from Dendrobium nobile Lindl. was investigated in this work. The response surface methodology (RSM) was combined with a Box-Behnken design to evaluate the influence that the three independent variables had on the response. The optimal extraction conditions (determined via RSM) were 129.83 °C extraction temperature, 16.71 min extraction time, and 1.12 MPa extraction pressure. The maximum predicted polysaccharide yield was 20.67%, which corresponded well with the experiential extraction (21.88%). The polysaccharides obtained from either the stirring extraction, refluxing extraction, ultrasound extraction, or SWE methods were compared, and the extraction processes were modeled. The molecular weight, monosaccharide composition, and antioxidative activities of the polysaccharides were analyzed.

The Preparation and Structure Analysis Methods of Natural Polysaccharides of Plants and Fungi: A Review of Recent Development

Polysaccharides are ubiquitous biomolecules found in nature that contain various biological and pharmacological activities that are employed in functional foods and therapeutic agents. Natural polysaccharides are obtained mainly by extraction and purification, which may serve as reliable procedures to enhance the quality and the yield of polysaccharide products. Moreover, structural analysis of polysaccharides proves to be promising and crucial for elucidating structure–activity relationships. Therefore, this report summarizes the recent developments and applications in extraction, separation, purification, and structural analysis of polysaccharides of plants and fungi.