Defatted Seeds of Oenothera biennis as a Potential Functional Food Ingredient for Diabetes

Avicularin is a minor aldose reductase inhibitor in defatted seeds of Oenothera biennis L.: Screening, inhibitory kinetics, and interaction mechanism

Inhibition of aldose reductase (AR) activity is promising for mitigating diabetic complications. Defatted evening primrose seeds (DO), a byproduct of evening primrose oil production, exhibits significant AR inhibitory effects. This study optimized extraction conditions of DO using response surface methodology to maximize the recovery of AR inhibitors (ARIs). A combination of high-speed countercurrent chromatography, affinity-based ultrafiltration, and high-performance liquid chromatography was used to screen ARIs from DO extract. Five compounds were identified as ARIs, with avicularin, a minor ARI, demonstrating the strongest inhibitory activity (IC50 = 4.17 μg mL-1). The inhibitory kinetics and interaction mechanisms of avicularin against AR were investigated, revealing that avicularin acts as a non-competitive inhibitor of AR (Ki = 4.42 μM). Avicularin quenched the intrinsic fluorescence of AR through static quenching, forming non-covalent complexes primarily via hydrogen bonds and van der Waals forces, while also altering the conformational structure and microenvironment of AR, impairing AR activity.

In Vitro and In Ovo Evaluation of Oenothera biennis L. Oil as an Alternative Preservative for Oil-Based Products

There is a growing need for safer alternatives to synthetic additives commonly used in lipophilic carriers for products such as foods, pharmaceuticals, personal care items, and cosmetics. Natural antioxidants, which prevent lipid peroxidation while providing additional health benefits, offer a promising solution. Evening primrose oil, a rich source of antioxidant compounds with numerous biological benefits, emerges as a potential natural preservative for oil-based products. Our study evaluates a combination of sunflower oil, a widely used cold-pressed oil, with evening primrose oil for potential applications in various fields such as cosmetic, pharmaceutical, or food manufacturing. Various methods were applied to assess oxidative stability by calculating the peroxide value, the p-anisidine value, and the total oxidation value, while biological safety was evaluated using the chick embryo's chorioallantoic membrane and histological analysis. The findings highlight that evening primrose oil, with its balanced effects on epithelial tissues and vascularization, as well as its strong anti-lipid peroxidation properties, is a suitable alternative to synthetic preservatives when used in combination with cold-pressed oils. This proposed oil combination, emphasizing the safety and beneficial properties of evening primrose oil, shows significant potential for applications in the pharmaceutical industry, dermatology, cosmetology, and food manufacturing.

Optimizing Green Extraction Methods for Maximizing the Biological Potential of Dandelion, Milk Thistle, and Chamomile Seed Extracts

This study investigates the underutilized potential of agri-crops from the Asteraceae family by employing sustainable and green technologies (supercritical fluid, ultrasound, and Soxhlet extractions) to enhance the recovery of bioactive compounds. A total of 21 extracts from native and waste seeds of dandelion, milk thistle, and chamomile were systematically compared utilizing a combination of solvents (supercritical CO2 and absolute or aqueous ethanol). Supercritical CO2 extraction yielded up to 281 mg/g of oils from native seeds, while conventional techniques with ethanol recovered an additional 142 mg/g of extracts from waste seeds. Notably, waste seed extracts exhibited superior biological activity, including potent antioxidant properties (IC50 values as low as 0.3 mg/mL in the DPPH assay) and broad-spectrum antimicrobial activity against 32 microbial strains, including methicillin-resistant Staphylococcus aureus, Gram-negative bacteria, and yeast strains. Phenolic compounds were abundant, with up to 2126 mg GAE/g, alongside 25.9 mg QE/g flavonoids, and 805.5 mg/kg chlorophyll A. A selective anticancer activity of waste milk thistle extracts was observed, with a selectivity index of 1.9 to 2.7. The oils recovered from native seeds demonstrated lower bioactivity and are well-suited for applications in food. The potent bioactivity of the smaller quantities of waste seed extracts positions them as valuable candidates for pharmaceutical use.

Antidiabetic potential of Amomum dealbatum Roxb. flower and isolation of three bioactive compounds with molecular docking and in vivo study

Amomum dealbatum Roxb. parts have been traditionally used as remedies for joint pain, diabetes, muscular rheumatism, antiseptic, and abscesses in Arunachal Pradesh, Assam, and Tripura. Ethyl acetate sub-fraction E3 had significantly inhibited the α-glucosidase (IC50 5.385 μg/mL). The molecular docking revealed quercetin-3-O-galactoside to be the most potent α-glucosidase inhibitor (binding energy -43.214 kcal/mol). Using the QSAR model, the pIC50 values of myricetin, gallic acid, quercetin-3-O-galactoside, and acarbose were predicted to be 5.65235, 4.39858, 5.65235, and 6.03058, respectively. For the first time, quercetin-3-O-galactoside, myricetin, and gallic acid have been isolated from the flowers of A. dealbatum (ADF). E3 decreased blood glucose level to a near-normal concentration (100.60 ± 2.94 mg/dL) in comparison to diabetic control rats (575.20 ± 24.80 mg/dL). The results have strongly suggested the potential of ADF in treating diabetes. This lesser-known plant has the potential to uncover its full medicinal properties through further in-depth research.

Oenothera biennis with strong copper toxicity resistance enriches trace copper in seeds under copper pollution soil

Excess copper (Cu) imparts negative effects on plant growth and productivity in soil. To develop the ability of O. biennis to govern pollution soil containing excessive Cu, we investigated seed germination, seedling growth, and seed yield. Furthermore, Cu content and the expression levels of Cu transport related genes in different tissues were measured under exogenous high concentration Cu. O. biennis seeds were sensitive to excess Cu, with an observed reduction in the germination rate, primary root length, fresh weight, and number of seeds germinated daily. Consecutive Cu stress did not cause fatal damage to evening primrose, yet it slowed down plant growth slightly by reducing the leaf water, chlorophyll, plant yield, and seed oil contents while increasing the soluble sugar, proline, malondialdehyde, and H2O2 contents. The Cu content in different organs of O. biennis was disrupted by excess Cu. In particular, the Cu content in O. biennis seeds and seed oil increased and subsequently decreased with the increase of exogenous Cu, reaching a peak under 600 mg·kg-1 consecutive Cu. Furthermore, the 4-month 900 mg·kg-1 Cu treatment did not induce the excessive accumulation of Cu in peels, seeds, and seed oil, maintaining the Cu content within the range required by the Chinese National Food Safety Standards. The treatment also resulted in an upregulation of Cu-uptake (ObCOPT5, ObZIP4, and ObYSL2) and vigorous efflux (ObHMA1) of transport genes, of which expression levels were significant positive correlation (p < 0.05) with the Cu content. Among all organs, the stem replaced the root as the organ exhibited the greatest ability to absorb and store Cu, and even the Cu transport genes could still function continuously in stem under excess Cu. This work identified a species that can tolerate high Cu content in soil while maintaining a high yield. Furthermore, the results revealed the enrichment of Cu to occur primarily in the O. biennis stem rather than the seeds and peel under excess Cu.

Identification of tyrosinase inhibitors in defatted seeds of evening primrose (Oenothera biennis L.) by affinity-labeled molecular networking

The defatted seeds of evening primrose (DE), a by-product of evening primrose oil extraction, are currently underutilized. This study aimed to valorize DE by examining its effects on melanogenesis and tyrosinase activity in zebrafish embryos and in vitro, and an innovative affinity-labeled molecular networking workflow was proposed for the rapid identification of tyrosinase inhibitors in DE. Our results indicated DE significantly reduced melanin content (53.3 % at 100 μg/mL) and tyrosinse activity (80.05 % for monophenolase and 70.40 % for diphenolase at 100 μg/mL). Furthermore, through the affinity-labeled molecular networking approach, 20 compounds were identified as potential tyrosinase inhibitors within DE, predominantly flavonoids and tannins characterized by catechin and galloyl substructures. Seven of these compounds were isolated and their inhibitory effects on tyrosinase were validated using functional assays. This study not only underscores the potential of DE as a rich source of natural tyrosinase inhibitors but also establishes the effectiveness of affinity-labeled molecular networking in pinpointing bioactive compounds in complex biological matrices.

Evening primrose oil: a comprehensive review of its bioactives, extraction, analysis, oil quality, therapeutic merits, and safety

Oil crops have become increasingly farmed worldwide because of their numerous functions in foods and health. In particular, oil derived from the seeds of evening primrose (Oenothera biennis) (EPO) comprises essential fatty acids of the omega-6 (ω-6) series. It is well recognized to promote immune cells with a healthy balance and management of female ailments. The nutrients of interest in this oil are linoleic acid (LA, 70-74%) and γ-linolenic acid (GLA, 8-10%), which are polyunsaturated fatty acids (PUFA) that account for EPO's popularity as a dietary supplement. Various other chemicals in EPO function together to supply the body with PUFA, elevate normal ω-6 essential fatty acid levels, and support general health and well-being. The inclusive EPO biochemical analysis further succeeded in identifying several other components, i.e., triterpenes, phenolic acids, tocopherols, and phytosterols of potential health benefits. This comprehensive review capitalizes on EPO, the superior product of O. biennis, highlighting the interrelationship between various methods of cultivation, extraction, holistic chemical composition, sensory characters, and medicinal value. Besides the literature review, this study restates the numerous health advantages of primrose oil and possible drug-EPO interactions since a wide spectrum of drugs are administered concomitantly with EPO. Modern techniques to evaluate EPO chemical composition are addressed with emphasis on the missing gaps and future perspectives to ensure best oil quality and nutraceutical benefits.

Screening and Evaluation of Active Compounds in Polyphenol Mixtures by a Novel AAPH Offline HPLC Method and Its Application

In this study, we developed a novel offline high-performance liquid chromatography (HPLC) method based on 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) radicals for antioxidant screening in 20 polyphenolic compounds and used the Trolox equivalent antioxidant capacity assay to evaluate their antioxidant activity. Compared to the existing offline HPLC methods based on 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH), the offline HPLC method based on the AAPH radical is more sensitive. Additionally, we applied this method to Lepechinia meyenii (Walp.) Epling extract and screened out seven antioxidants, caffeic acid, hesperidin, rosmarinic acid, diosmin, methyl rosmarinate, diosmetin, and n-butyl rosmarinate, which are known antioxidants. Therefore, this study provides new insights into the screening of antioxidants in natural extracts.

Oxidative Stability and Protective Effect of the Mixture between Helianthus annuus L. and Oenothera biennis L. Oils on 3D Tissue Models of Skin Irritation and Phototoxicity

The present study was aimed to evaluate the oxidative stability as well as to assess the protective effect of the mixture of Helianthus annuus L. (HAO) and Oenothera biennis L. (OBO) oils on 3D tissue models of skin irritation and phototoxicity. The following methods were used: GS analysis (fatty acids composition), thiobarbituric acid-reactive substances assay (TBA) (lipid oxidation degree of tested samples), 3D EpiDerm models (skin irritation and phototoxicity). For HAO the detected saturated fatty acids (SFA) were palmitic acid (7.179%), stearic acid (3.586%), eicosanoic (0.138%) and docosanoic acid (0.548%) The monounsaturated acids (MUFA) were palmitoleic acid (0.158%) and oleic acid (28.249%) and the polyunsaturated acids (PUFA) were linoleic acid (59.941%) and linolenic acid (0.208%). For OBO the detected SFA were myristic acid (0.325%), pentadecylic acid (0.281%), palmitic (7.2%), stearic (2.88%), and arachidic acid (0.275%). Regarding MUFA, even a lower proportion (8.196%) was observed, predominantly being oleic acid, cis form (7.175%), oleic (n10) (0.558%) and 11-eicosenoic (0.210%) acids. The higher content was found for PUFA (82.247%), the most significant proportions being linoleic acid (72.093%), arachidonic acid (9.812%) and linolenic (0.233%). Obtained data indicate a good oxidative stability and biocompatibility of the mixture on the 3D EpiDerm models with no irritant and no phototoxic effects. Oenothera biennis L. oil may be an excellent natural choice in order to delay or prevent oxidative damage of Helianthus annuus L. oil.

Characterization, Hypoglycemic Activity, and Antioxidant Activity of Methanol Extracts From Amomum tsao-ko: in vitro and in vivo Studies

The dried fruit of Amomum tsao-ko is well-known as a spice as well as a Chinese traditional herb. This study aimed to identify the bioactive constituents in the powder of methanol extract from Amomum tsao-ko (PMEAT) and to evaluate the hypoglycemic and antioxidant effects of PMEAT, in vitro and in vivo. We identified 36 phytochemicals in PMEAT by employing HPLC-MS/MS. PMEAT solution was found to have potent α-glucosidase-inhibiting activity (IC₅₀, 0.145 mg/mL) in vitro, twice as strong as that of acarbose (IC₅₀, 0.273 mg/mL). To investigate the hypoglycemic activity of PMEAT in vivo, we studied the impact of low-dose PMEAT (the addition of 100 mg/kg PMEAT to the mice diet) and high-dose PMEAT (200 mg/kg PMEAT addition) treatments in STZ-induced diabetic mice. After 6 weeks of intervention, significantly decreased fasting blood glucose (FBG) (p < 0.05), significantly decreased area under the curve (AUC) of the oral glucose tolerance test (p < 0.05), significantly decreased HOMA-IR (p < 0.05), and significantly increased HOMA-β (p < 0.05) were observed in the high-dose PMEAT group. Moreover, we performed an antioxidant activity experiment in vitro. The results showed that PMEAT had a strong ability to scavenge DPPH (IC₅₀, 0.044 mg/mL) as well as ABTS free radicals (IC₅₀, 0.040 mg/mL). In an animal experiment conducted on oxidative damage mice model which was induced by D-glucose and a high-fat diet, we observed significantly increased dismutase (SOD) (p < 0.01), glutathione (GSH) (p < 0.01), and glutathione peroxidase (GSH-Px) (p < 0.01) and significantly reduced malondialdehyde (MDA) and 8-ISO-prostaglandin-PGF2α (8-ISO-PGF2α), after treatment with PMEAT for 90 days. In conclusion, this study reveals the therapeutic potential of Amomum tsao-ko for the treatment of diabetes and helps us discover new antioxidant candidates from natural sources.

Comparative Study of Natural Antioxidants from Glycine max, Anethum graveolensand Pimpinella anisum Seed and Sprout Extracts Obtained by Ultrasound-Assisted Extraction

The study aimed to evaluate the antioxidant potential of sprout and seed extracts from three species of plants, namely Glycine max (GMsp-sprouts, GMsd-seeds), Anethum graveolens (AGsp-sprouts, AGsd-seeds) and Pimpinella anisum (PAsp-sprouts, PAsd-seeds), which are widely accepted by consumers and have various applications in food flavoring, and also in natural medical treatments in the pharmaceutical industries. These plants are rich in valuable compounds that show a remarkable antioxidant power and are associated with many health benefits. Ethanol extracts were obtained by ultrasound-assisted extraction and they were comparatively evaluated for their in vitro antioxidant properties. The extracts were characterized by HPTLC, HPLC-DAD, total phenol content (TPC), total flavonoid content (TFC) analysis and antioxidant activities with different assays, such as total antioxidant capacity (TAC), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical cation decolorization assay (ABTS), 1,1-diphenyl 1-2-picryl-hydrazyl (DPPH) and iron binding ability of chelators. Our results showed that the sprout and seed extracts of the studied plants exhibited a high content of phytochemicals and promising antioxidant properties. The highest polyphenols content was detected for AGsd (53.02 ± 0.57 mg/g DW), PAsd (48.75 ± 0.34 mg/g DW) and the highest flavonoids content for PAsp (26.84 ± 0.57 mg/g DW). Moreover, the presence of valuable compounds was demonstrated by using HPTLC, FT-IR and HPLC-DAD techniques. In order to have a better understanding of the relationship between the biological properties and the electronic structure, a molecular modelling study of genistein was also conducted. Our approach to the comparative assessment of these three plant species was based on a priori knowledge from literature data; however, this study demonstrated that these plant extracts of seeds and also sprouts are excellent sources of natural antioxidants. Significant additional differences that were found in the phytochemical composition could be exploited in future research for pharmaceutical purposes.

Surface tension of native and modified plant seed proteins

The present review, dedicated to Prof. Zbigniew Adamczyk on the occasion of his 70th anniversary, covers the literature data on surface tension and surface compression (dilational) rheology of the adsorbed layers of 21 plant seed proteins (10 leguminous and 11 non-leguminous plants). They are typically analyzed as protein concentrates or isolates, the latter usually obtained by isoelectric precipitation or diafiltration. Despite generally lower solubility, as compared to their animal counterparts (lactoglobulins, caseins, albumins, etc.), the plant seed proteins are also capable of lowering surface tension and forming viscoelastic adsorbed layers. Many seed proteins serve mostly as amino acids reservoirs for the future seedling (storage proteins), hence their instantaneous amphiphilicity is not always sufficient to induce strong adsorption at the aqueous-air interface. They can be, however, conveniently unfolded, hydrolyzed and/or chemically/enzymatically modified to expose more hydrophilic or hydrophobic patches. As shown in numerous contributions reviewed below, the resulting shift of the hydrophilic-lipophilic balance can boost their surface activity to the level comparable to that of many animal proteins or low molecular weight surfactants. An important advantage of the plant seed proteins over the animal ones is their much lower environmental cost and abundance in many plants (e.g. ~40% in sunflower or soybean seeds).

In situ net fishing of α-glucosidase inhibitors from evening primrose (Oenothera biennis) defatted seeds by combination of LC-MS/MS, molecular networking, affinity-based ultrafiltration, and molecular docking

Defatted seeds of evening primrose (DSEP), the by-product of evening primrose oil manufacture, exhibit potential α-glucosidase inhibitory activity; however, presently they are routinely discarded as waste. In this study, an in situ net fishing strategy was proposed for rapid recognition of α-glucosidase inhibitors from DSEP. Firstly, the DSEP extraction method was optimized employing a response surface methodology for the recovery of α-glucosidase inhibitors, just like "finding a good fishery before net fishing". Then, molecular networks of DSEP were generated by GNPS-based molecular networking after LC-MS/MS analysis, just like "casting tight nets in the fishery". Subsequently, affinity-based ultrafiltration was carried out for fishing the "hit" together with its structural analogues according to the molecular networks, just like "hauling the specific net fishing". Finally, molecular docking analysis was performed to rapidly verify α-glucosidase inhibitory activities of the potential bioactive components and predict their inhibition mechanisms. In the results, DSEP displayed significant inhibitory effects against yeast and rat intestinal α-glucosidase, and the results of an oral starch tolerance test suggested that DSEP showed postprandial blood-glucose-lowering activity. Moreover, 1-galloyl-glucose, gallic acid, methyl gallate, 1,6-digalloyl-β-D-glucose, and 1,3,6-trigalloylglucose were rapidly identified as potential α-glucosidase inhibitors present in DSEP.

Efficient Extraction of Total Polyphenols from Apple and Investigation of Its SPF Properties

The purpose of this study was to evaluate the sun protection factor (SPF) of cosmetic emulsions with the addition of hydroalcoholic apple extract. First, the total polyphenolic content, the antioxidant activity and SPF properties of the extracts obtained by sonication and refluxing were evaluated. The two extraction methods were improved using the central composite design. For cosmetic emulsion that contained a different concentration of apple extract (10-40%), a SPF value between 0.51 and 0.90 was obtained. The most efficient apple extract was obtained by reflux using 50% ethanol and a 60 min extraction time. The concentrated extract was incorporated in a cosmetic emulsion whose SPF maximum was 0.90. Accordingly, due to photoprotective properties, the apple extract can be a candidate for use in cosmetic formulations.

Evening primrose seed extract rich in polyphenols modulates the invasiveness of colon cancer cells by regulating the TYMS expression

Natural polyphenols are plant metabolites exhibiting a broad range of biological activities.

Separation and Identification of Antioxidants and Aldose Reductase Inhibitors in Lepechinia meyenii (Walp.) Epling

We previously reported that Lepechinia meyenii (Walp.) Epling has antioxidant and aldose reductase (AR) inhibitory activities. In this study, L. meyenii was extracted in a 50% MeOH and CH₂Cl₂/MeOH system. The active extracts of MeOH and 50% MeOH were subjected to fractionation, followed by separation using high-speed counter-current chromatography (HSCCC) and preparative HPLC. Separation and identification revealed the presence of caffeic acid, hesperidin, rosmarinic acid, diosmin, methyl rosmarinate, diosmetin, and butyl rosmarinate. Of these, rosmarinic acid, methyl rosmarinate, and butyl rosmarinate possessed remarkable antioxidant and AR inhibitory activities. The other compounds were less active. In particular, rosmarinic acid is the key contributor to the antioxidant and AR inhibitory activities of L. meyenii; it is rich in the MeOH extract (333.84 mg/g) and 50% MeOH extract (135.41 mg/g) of L. meyenii and is especially abundant in the EtOAc and n-BuOH fractions (373.71-804.07 mg/g) of the MeOH and 50% MeOH extracts. The results clarified the basis of antioxidant and AR inhibitory activity of L. meyenii, adding scientific evidence supporting its traditional use as an anti-diabetic herbal medicine. The HSCCC separation method established in this study can be used for the preparative separation of rosmarinic acid from natural products.

Linking the Phytochemicals and the α-Glucosidase and α-Amylase Enzyme Inhibitory Effects of Nigella sativa Seed Extracts

Nigella sativa L. (Ranunculaceae), commonly referred to as black seeds or black cumin, is used in popular medicine (herbal) all over the world for the treatment and prevention of several diseases, including diabetes. This study aims to investigate the inhibitory effect of N. sativa extracts and fractions against the activities of intestinal α-glucosidase and pancreatic α-amylase in vitro, and to explain the inhibitory effect of these fractions against these enzymes by identifying their active compounds responsible for this effect and determine their modes of inhibition. To do so, N. sativa hexane and acetone extracts were prepared and analyzed by GC-MS and HPLC-DAD, respectively. The hexane extract was further fractioned into eight different fractions, while the acetone extract generated eleven fractions. The extracts as well as the resulting fractions were characterized and evaluated for their potential in vitro antidiabetic activity using intestinal α-glucosidase and pancreatic α-amylase inhibitory assays in vitro. Hexane extract and fractions were less active than acetone extract and fractions. In the case of intestinal α-glucosidase activity, the acetone fraction SA3 had a high inhibitory effect on intestinal α-glucosidase activity with 72.26 ± 1.42%, comparable to the effect of acarbose (70.90 ± 1.12%). For the pancreatic α-amylase enzymatic inhibitory assay, the acetone fractions showed an inhibitory capacity close to that for acarbose. In particular, the SA2 fraction had an inhibitory effect of 67.70 ± 0.58% and was rich in apigenin and gallic acid. From these fractions, apigenin, (-)-catechin, and gallic acid were further characterized for their inhibitory actions. IC₅₀ and inhibition mode were determined by analyzing enzyme kinetic parameters and by molecular modeling. Interestingly, (-)-catechin showed a possible synergistic effect with acarbose toward α-glucosidase enzyme inhibition, whereas apigenin showed an additive effect with acarbose toward α-amylase enzymatic inhibition. Furthermore, we studied the toxicity of N. sativa hexane and acetone extracts as well as that of acetone fractions. The result of acute toxicity evaluation demonstrated that N. sativa extracts were nontoxic up to a concentration of 10 g/kg, except for fraction SA3. Taken together, these results indicate that N. sativa extracts and/or derived compounds could constitute promising nutraceuticals for the prevention and treatment of type 2 diabetes mellitus.

Valeriana rigida Ruiz & Pav. Root Extract: A New Source of Caffeoylquinic Acids with Antioxidant and Aldose Reductase Inhibitory Activities

Valeriana rigida Ruiz & Pav. (V. rigida) has long been used as a herbal medicine in Peru; however, its phytochemicals and pharmacology need to be scientifically explored. In this study, we combined the offline 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH)-/ultrafiltration-high-performance liquid chromatography (HPLC) and high-speed counter-current chromatography (HSCCC)/pH-zone-refining counter-current chromatography (pH-zone-refining CCC) to screen and separate the antioxidants and aldose reductase (AR) inhibitors from the 70% MeOH extract of V. rigida, which exhibited remarkable antioxidant and AR inhibitory activities. Seven compounds were initially screened as target compounds exhibiting dual antioxidant and AR inhibitory activities using DPPH-/ultrafiltration-HPLC, which guided the subsequent pH-zone-refining CCC and HSCCC separations of these target compounds, namely 3-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 5-O-caffeoylquinic acid, 3,4-O-di-caffeoylquinic acid, 3,5-O-di-caffeoylquinic acid, 4,5-O-di-caffeoylquinic acid, and 3,4,5-O-tri-caffeoylquinic acid. These compounds are identified for the first time in V. rigida and exhibited remarkable antioxidant and AR inhibitory activities. The results demonstrate that the method established in this study can be used to efficiently screen and separate the antioxidants and AR inhibitors from natural products and, particularly, the root extract of V. rigida is a new source of caffeoylquinic acids with antioxidant and AR inhibitory activities, and it can be used as a potential functional food ingredient for diabetes.