Evaluation of Polyphenolic Composition and Antimicrobial Properties of Sanguisorba officinalis L. and Sanguisorba minor Scop

Extraction of Sanguisorba officinalis L. polysaccharide by ultrasound-assisted extraction: structural characterization, antioxidant, hemostatic and immunological activity

Sanguisorba officinalis L. (S. officinalis) has been widely distributed in various regions of China and holds significant potential for various applications. However, limited studies have focused on S. officinalis polysaccharides (SOPs) and their biological activities. Utilizing response surface methodology (RSM), the process of ultrasonic-assisted extraction of SOPs was optimized. The optimal conditions were 270.2 W, 42.4 mL/g, and 47.7 min. Through separation and purification, a neutral polysaccharide named SOUP-1 was obtained. SOUP-1 (17.1 kDa) mainly includes glucose and a few galactose, mannose, and arabinose. The main chain of SOUP-1 is primarily → 4)-α-D-Glcp-(1 → 4,6)-α-D-Glcp-(1 → substituted at C6 with branch chain → 6)-α-D-Glcp-(1 → . Furthermore, SOUP-1 showed antioxidant activity, including scavenging activities of hydroxyl radicals and DPPH. It also enhances macrophage phagocytic activity and modulates the expression of inflammatory cytokines such as TNF-α and IL-6. Additionally, this study first discovered the hemostatic activity of SOUP-1. This study provides theoretical support for the potential applications and further research of SOPs. It provides a basis for the development of SOPs as novel natural-source immunomodulators in the food and pharmaceutical industries.

Unlocking the potential of plant polyphenols: advances in extraction, antibacterial mechanisms, and future applications

Plant polyphenols are widely distributed in most higher plants, garnering significant attention from researchers due to their remarkable antioxidative, antibacterial, anticancer, and anti-radiation properties. They also offer multiple health benefits for various lifestyle-related diseases and oxidative stress. While there has been considerable research on the extraction and antibacterial application of plant polyphenols, developing a rapid and efficient extraction method remains a persistent challenge. Furthermore, the introduction of novel technologies is imperative to enhance the bioavailability of polyphenolic compounds. This comprehensive review synthesizes recent research findings pertaining to the extraction, antibacterial mechanisms, and applications of plant polyphenols. This research highlights the prevalent issues of low extraction rates of plant polyphenols and the ambiguous antibacterial mechanisms in current research. To address these challenges, this research proposes innovative directions for improving extraction technology and expanding antibacterial applications. Additionally, this review outlines promising future research avenues within the realm of plant polyphenols.

Graphical abstract

Sanguisorba officinalis L. ethanolic extracts and essential oil - chemical composition, antioxidant potential, antibacterial activity, and ex vivo skin permeation study

Introduction

Sanguisorba officinalis L. is classified as a medicinal plant and used in traditional medicine. The root of this plant is mainly used as a medicinal raw material, but the above-ground parts are also a valuable source of health-promoting biologically active compounds.

Method

The study aimed to evaluate the antioxidant activity and total polyphenol content (TPC) of extracts prepared in 70% and 40% aqueous ethanol solution (dry extract content 50-500 g/L) from the aerial parts of S. officinalis. The essential oil was isolated from the tested raw material, and its composition was determined using GC-MS. Ethanolic extracts and essential oil have been tested for antibacterial activity. The extract in 70% v/v ethanol (dry extract content: 500 g/L) was subjected to HPLC analysis for the content of selected phenolic acids and an ex vivo skin permeation study. The ability of these metabolites to permeate and accumulate in the skin was analysed.

Results

Extracts prepared at both ethanol concentrations showed similar antioxidant activity and TPC. Depending on the method, concentration of solvent, and dry extract content (50-500 g/L), the activity ranged from 1.97 to 84.54 g Trolox/L. TPC range of 3.80-37.04 g GA/L. Gallic acid (424 mg/L) and vanillic acid (270 mg/L) had the highest concentrations among the phenolic acids analysed. Vanillic acid (10 μg) permeates the skin at the highest concentration. The highest accumulation in the skin was found for 2,5-dihydroxybenzoic acid (53 μg/g skin), 2,3-dihydroxybenzoic acid (45 μg/g skin), and gallic acid (45 μg/g skin). The tested ethanolic extracts exhibited antibacterial activity. Samples with a dry extract concentration of 500 g/L showed the largest growth inhibition zones. The most sensitive strains to these extracts were P. aeruginosa (24 mm), S. lutea (23 mm), and S. pneumoniae (22 mm). The smallest inhibition zones were observed for B. subtilis (17 mm). The essential oil showed weaker antimicrobial activity (growth inhibition zone 8-10 mm). The GC-MS method identified 22 major components of the essential oil, including aliphatic hydrocarbons, unsaturated terpene alcohols, aliphatic aldehydes, unsaturated and saturated fatty acids, sesquiterpene, phytyl ester of linoleic acid, nitrogen compound, phytosterol, terpene ketone, phenylpropanoids, aliphatic alcohol, diterpenoid, aromatic aldehyde, and aliphatic carboxylic acid.

Discussion

The conducted research has shown that ethanolic extracts from Sanguisorbae herba are a valuable source of compounds with antibacterial and antioxidant potential, including phenolic acids. The fact that selected phenolic acids contained in the tested extract have the ability to permeate and accumulate in the skin provides the basis for conducting extended research on the use of extracts from this plant raw material in cosmetic and pharmaceutical preparations applied to the skin.

Antimicrobial Metabolites of Caucasian Medicinal Plants as Alternatives to Antibiotics

This review explores the potential of antimicrobial metabolites derived from Caucasian medicinal plants as alternatives to conventional antibiotics. With the rise of antibiotic resistance posing a global health threat, there is a pressing need to investigate alternative sources of antimicrobial agents. Caucasian medicinal plants have traditionally been used for their therapeutic properties, and recent research has highlighted their potential as sources of antimicrobial compounds. Representatives of 15 families of Caucasian medicinal plant extracts (24 species) have been explored for their efficacy against these pathogens. The effect of these plants on Gram-positive and Gram-negative bacteria and fungi is discussed in this paper. By harnessing the bioactive metabolites present in these plants, this study aims to contribute to the development of new antimicrobial treatments that can effectively combat bacterial infections while minimizing the risk of resistance emergence. Herein we discuss the following classes of bioactive compounds exhibiting antimicrobial activity: phenolic compounds, flavonoids, tannins, terpenes, saponins, alkaloids, and sulfur-containing compounds of Allium species. The review discusses the pharmacological properties of selected Caucasian medicinal plants, the extraction and characterization of these antimicrobial metabolites, the mechanisms of action of antibacterial and antifungal plant compounds, and their potential applications in clinical settings. Additionally, challenges and future directions in the research of antimicrobial metabolites from Caucasian medicinal plants are addressed.

Assessment of Chemical Composition and In Vitro Antioxidant, Antidiabetic, Anticholinesterase and Microbial Virulence-Quenching Effects of Salad Burnet (Sanguisorba minor L.) Harvested from Algeria

Sanguisorba minor is a medicinal vegetable used in seasoning desserts, juices, and beverages. An evaluation of the total flavonoid, phenolic, tannin and anthocyanin contents indicated that these classes of compounds are distributed variably in the different fractions. In summary, the HPLC-DAD analyses enabled the identification and quantification of thirteen phenolic compounds in an ethyl acetate extract (EAE), nine in a dichloromethane extract (DCME), seven in an aqueous extract (AQE) and four in a butanol extract (BE). Rutin was the most abundant phenolic compound in the BE (278.4 ± 1.20 µg/g) and AQE (32.87 ± 0.23 µg/g) fractions, while apigenin was the most abundant in the DCME (84.75 ± 0.60 µg/g) and EAE (156.8 ± 0.95 µg/g) fractions. The presence of phenolic compounds in the fractions conferred good antioxidant capacity, especially the EAE and DCME fractions, which both exhibited higher antioxidant effects than BHA and α-tocopherol in DPPH• and CUPRAC assays. Additionally, in the ABTS•+ assay, EAE (IC50 = 9.27 ± 0.33 µg/mL) was more active than α-tocopherol (IC50 = 35.50 ± 0.55 µg/mL), and BHA (IC50 = 12.70 ± 0.10 µg/mL). At 200 µg/mL, the fractions inhibited acetylcholinesterase and butyrylcholinesterase as well as α-amylase and α-glucosidase, indicating that they can slow neurodegeneration and hyperglycemia. Minimal inhibitory concentration (MIC) values ranged from 0.312 mg/mL to 1.25 mg/mL, and fractions showed good biofilm inhibition against Staphylococcus aureus and Escherichia coli. The extracts exhibited good violacein inhibition in Chromobacterium violaceum CV12472 and Chromobacterium violaceum CV026, despite the supply of external acyl-homoserine lactone to CV026. The antioxidant, quorum-sensing, antibiofilm and enzyme inhibition attributes indicate the potential for the application of S. minor as a food preservative.

Hypotensive and Vasorelaxant Effects of Sanguisorbae Radix Ethanol Extract in Spontaneously Hypertensive and Sprague Dawley Rats

Hypertension requires proper management because of the increased risk of cardiovascular disease and death. For this purpose, functional foods containing tannins have been considered an effective treatment. Sanguisorbae radix (SR) also contains various tannins; however, there have been no studies on its vasorelaxant or antihypertensive effects. In this study, the vasorelaxant effect of the ethanol extract of SR (SRE) was investigated in the thoracic aorta of Sprague Dawley rats. SRE (1, 3, 10, 30, and 100 μg/mL) showed this effect in a dose-dependent manner, and its mechanisms were related to the NO/cGMP pathway and voltage-gated K+ channels. Concentrations of 300 and 1000 μg/mL blocked the influx of extracellular Ca2+ and inhibited vasoconstriction. Moreover, 100 μg/mL of SRE showed a relaxing effect on blood vessels constricted by angiotensin II. The hypotensive effect of SRE was investigated in spontaneously hypertensive rats (SHR) using the tail-cuff method. Blood pressure significantly decreased 4 and 8 h after 1000 mg/kg of SRE administration. Considering these hypotensive effects and the vasorelaxant mechanisms of SRE, our findings suggests that SRE can be used as a functional food to prevent and treat hypertension. Further studies are needed for identifying the active components and determining the optimal dosage.

Sanguisorba minor Scop.: An Overview of Its Phytochemistry and Biological Effects

Since ancient times, many plants have been cultivated for their nutritional and medicinal properties. The genus Sanguisorba has been used for medicinal purposes for more than 2000 years. These species are distributed in temperate, arctic, or alpine areas in the Northern Hemisphere. Elongated, imparipinnate leaves and densely clustered flower heads are characteristics of the genus Sanguisorba. While Sanguisorba officinalis L. is mainly known for its significant medicinal applications, Sanguisorba minor Scop. is beginning to attract greater interest for its chemical composition and biological effects. Our research collected extensive information on Sanguisorba minor, including its history, taxonomy, habitat, and distribution, as well as its bioactive components and biological activities. In addition to electron microscopy of plant parts (root, stems, and leaves), which is described for the first time in the literature in the case of S. minor, the study also provides information on potential pests or beneficial insects that may be present. Our goal was to provide important information that will serve as a solid foundation for upcoming research on Sanguisorba minor Scop.