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Flavonoids are considered one of the most diverse phenolic compounds possessing several valuable health benefits. The present study aimed at gathering all correlated reports, in which Sephadex® LH-20 (SLH) has been utilized as the final step to isolate or purify of flavonoid derivatives among all plant families. Overall, 189 flavonoids have been documented, while the majority were identified from the Asteraceae, Moraceae, and Poaceae families. Application of SLH has led to isolate 79 flavonols, 63 flavones, and 18 flavanones. Homoisoflavanoids, and proanthocyanidins have only been isolated from the Asparagaceae and Lauraceae families, respectively, while the Asteraceae was the richest in flavones possessing 22 derivatives. Six flavones, four flavonols, three homoisoflavonoids, one flavanone, a flavanol, and an isoflavanol have been isolated as the new secondary metabolites. This technique has been able to isolate quercetin from 19 plant species, along with its 31 derivatives. Pure methanol and in combination with water, chloroform, and dichloromethane have generally been used as eluents. This comprehensive review provides significant information regarding to remarkably use of SLH in isolation and purification of flavonoids from all the plant families; thus, it might be considered an appreciable guideline for further phytochemical investigation of these compounds.

Grape seeds are a copious part of the grape pomace produced by wine and juice industry and they represent an interesting source of phenolic compounds. Proanthocyanidins (PAs) are the main class of grape seed phenols and are important dietary supplements for their well-known beneficial properties. In this study enriched extracts obtained from Chardonnay and Pignoletto grape seeds were characterized for their proanthocyanidins and other minor phenolic compounds content and composition. Seed PAs were fractionated using Sephadex LH-20, using different ethanol aqueous solutions as mobile phase and analysed by normal phase HPLC-FLD-ESI-MS. Monomers, oligomers up to dodecamers and polymers were recorded in all samples. For both cultivars, the extracts showed a high content in PAs. The determination of other phenolic compounds was carried out using a HPLC-QqQ-ESI-MS and Chardonnay samples reported a greater content compared to Pignoletto samples. Contrary to PAs fraction, extracts obtained with ethanol/water 50/50 (v/v) presented a significant higher phenolic content than the others.

The antioxidant activity and phenolic compound profiles of six fractions (I–VI) obtained from sunflower seed extract were studied. HPLC–MS(ESI) analysis was applied for quantitative and qualitative determination of phenolic compounds of the fractions. The antioxidant activity of the fractions was studied in terms of their ability to scavenge DPPH · and ABTS ·+ and to reduce Fe 3+ /ferricyanide complex to the ferrous form and was expressed as EC 50 , TEAC and reducing power values, respectively. The results of all antioxidant activity tests showed good correlations among each other and with the phenolic contents for the individual fractions. The fractions IV–VI were characterized by high antioxidant activity. 5- O -Caffeoylquinic acid was a predominant compound of fractions IV and V, while dicaffeoylquinic acid isomers and caffeoyl-dimethoxycinnamoylquinic acid isomers accounted for 76.6 % of phenolic compounds of fraction VI. Ferulic acid, p -coumaroylquinic acid isomers, ferulic acid dehydrotrimer isomers and some quercetin derivatives were also identified. The highest content of those compounds was noted in fraction III.

Cowpea (Vigna unguiculata L.) pods are an underexploited by-product of legume production with significant antioxidant potential. Their recovery and characterization support sustainable waste valorization in agri-food systems. This study aimed to optimize the extraction of phenolic compounds (PCs) with antioxidant capacity (AOC) from cowpea pods and identify key bioactives through experimental and theoretical approaches. First, high-intensity ultrasound extraction was optimized using response surface methodology with ethanol–water mixtures. Under optimal conditions (20% amplitude, 15 min, 50% ethanol), the ethanolic extract (Eo) showed higher total phenolic content (TPC) and AOC than the aqueous extract (Wo). Subsequently, fractionation by Sephadex LH-20 chromatography yielded fractions E2 and W2 with enhanced TPC and AOC. Phytochemical profiling showed that E2 was enriched in caftaric acid, p-coumaric acid, and morin, while W2 had higher levels of caftaric, p-coumaric, and caffeic acids. Finally, density functional theory was used to assess thermodynamic parameters linked to antioxidant mechanisms (HAT, SET-PT, SPLET), revealing morin as the most effective radical scavenger, followed by caffeic and caftaric acids. These findings show that AOC depends not only on phenolic concentration but also on molecular structure and solvent interactions. Thus, cowpea pod extracts and fractions hold promise for antioxidant-rich formulations in food, nutraceutical, or cosmetic applications.

Two prenylated biflavonoids, podoverines B–C, were isolated from the dried roots and rhizomes of Sinopodophyllum emodi using a Sephadex LH-20 column (SLHC) and high-speed counter-current chromatography (HSCCC). The 95% ethanol extract was partitioned with ethyl acetate in water. Target compounds from the ethyl acetate fraction were further enriched and purified by the combined application of SLHC and HSCCC. n-Hexane–ethyl acetate–methanol–water (3.5:5:3.5:5, v/v) was chosen as the two phase solvent system. The flow rate of mobile phase was optimized at 2.0 mL·min−1. Finally, under optimized conditions, 13.8 mg of podoverine B and 16.2 mg of podoverine C were obtained from 200 mg of the enriched sample. The purities of podoverines B and C were 98.62% and 99.05%, respectively, as determined by HPLC. For the first time, podoverins B and C were found in the genus Sinopodophyllum. Their structures were determined by spectroscopic methods (HR-ESI-MS, 1H-NMR, 13C-NMR, HSQC, HMBC). Their absolute configurations were elucidated by comparison of their experimental and calculated ECD spectra. The cytotoxic activities were evaluated against MCF-7 and HepG2 cell lines. The separation procedures proved to be practical and economical, especially for trace prenylated biflavonoids from traditional Chinese medicine.

Previous investigations of H. oreadica reported the presence of a wide spectrum of complex limonoids and dihydrocinnamic acids. Our interest in the Rutaceae motivated a reinvestigation of H. oreadica, H. brasiliana and H. superba searching for other secondary metabolites present in substantial amounts for taxonomic analysis. In a continuation of the investigation of the H. oreadica, three new limonoids have now been isolated 9α-hydroxyhortiolide A, 11β-hydroxyhortiolide C and 1(S*)-acetoxy-7(R*)-hydroxy-7-deoxoinchangin. All the isolated compounds from the Hortia species reinforce its position in the Rutaceae. With regard to limonoids the genus produces highly specialized compounds, whose structural variations do not occur in any other member of the Rutaceae, thus, it is evident from limonoid data that Hortia takes an isolated position within the family. In addition, H. superba afforded the unexpected coumarin 5-chloro-8-methoxy-psoralen, which may not be a genuine natural product. Solid-state cross-polarisation/magic-angle-spinning 13C nuclear magnetic resonance, X-Ray fluorescence and Field-emission gun scanning electron microscopy experiments show that the Sephadex LH-20 was modified after treatment with NaOCl, suggesting that when xanthotoxin (8-methoxy-psoralen) was extracted from cleaning of the gel column, chlorination of the aromatic system occurred.

Five fractions of phenolic compounds were obtained from the extract of common buckwheat seed (Fagopyrum esculentum Moench) using Sephadex LH-20 column chromatography with methanol as a mobile phase. The total phenolics content ranged from 19.8±1.5 (fraction I) to 164±2.2 mg (+)-catechin eq/g (fraction IV). The profiles of phenolic acids and flavonoids in the fractions were analysed using RP-HPLC-DAD. The antioxidant activity was tested as ABTS and DPPH scavenging activity and capability to reduce the Fe(III)/2,4,6-Tris(2-pyridyl)-s-triazine complex to the ferrous form. Results were expressed as Trolox equivalent antioxidant capacity (TEAC), IC and ferric reducing antioxidant power (FRAP) values, respectively. The highest antioxidant activity was noted for fraction IV that was predominated by flavones. TEAC, IC and FRAP values were: 1.47±0.01 mmol Trolox eq/g, 0.058±0.003 mg/assay and 2.18±0.05 mmol Fe(II)/g, respectively. Rutin constituted 77.7% of the compounds identified in fraction III. The antiradical activity and reducing capability of this fraction were lower compared to fraction IV, but significantly higher than in fractions I and II. The main phenolic compounds of fractions I and II were phenolic acids (caffeic, 5-O-caffeoylquinic and p-coumaric). The antioxidant activity of fraction V was similar to that of fraction III.

The activation of PLA2 by means of pro-inflammatory cytokines results in the subsequent release of arachidonic acid (AA) and generates eicosanoids, which further propagate inflammation. By 6the cyclooxygenases (COX1/2) responsible for the enzymatic conversion of AA to eicosanoids, the non-steroidal anti-inflammatory drugs are effective in relieving the pain and discomfort of inflammation. By using AA release assay as a guide for biological and anti-inflammatory activity, novel compound 1-O-(3-O-linolenoyl-6-deoxy-6-sulfo-?-D-glucopyranosyl)-glycerol (1) together with five known compounds isovitexin, byzantionoside B, tricin 4?-O-(erythro-?-guaiacylglyceryl) ether 7-O-?-glucopyranoside, 1-O-feruloyl glycerol and tricin 7-glucoside were isolated from the methanol extract of the aerial parts of Sclerochloa dura using LC techniques (Sephadex LH-20 column chromatography, preparative HPLC and semi-preparative HPLC). All isolated compounds were identified using spectroscopic NMR spectroscopy and MS spectrometry. Novel compound (1) was found to be an effective inhibitor of AA release with an IC50 value of 0.09 ? 0.03 mg mL-1. nema

Salvianolic acid B (Sal B) is the most abundant representative compound in roots of dansham (Salvia miltiorrhiza) which is beneficial in treatment of cardiovascular disease. The present study was performed to establish a large scale isolation method of Sal B in high purity from dansham roots. Water suspension of dansham roots’ (100 g d.w.) methanol extract (13.16 g) was partitioned with chloroform, and the water layer was adjusted to pH 3.0 by triflouroacetic acid, because the Sal B partition coefficient in acidic condition was predominately higher than that in neutral condition, and then continuously extracted with ethyl acetate (EtOAc). The EtOAc-soluble acidic fraction was subjected to Sephadex LH-20 column chromatography. The fractions (Ve/Vt 1.75–2.71, 1.82 g) containing Sal B were finally purified by preparative high performance liquid chromatography using an octadecylsilane column. The isolated Sal B fraction (1.08 g) represented a 75.0% recovery, with a purity exceeding 99.2%.

In order to investigate the utilization of wild grape by-products, isolation of proanthocyanidin from the wild grape seed (Vitis amurensis) and its antioxidant capacities were examined. 70% acetone crude extract of the wild grape seed was fractionated. The ethyl acetate fraction was applied to Sephadex LH-20 column chromatography, which was eluted with 50%, 75% methanol, and 75% acetone, respectively, and 9 fractions were collected, finally. Their proanthocyanidin characteristics and contents were investigated by vanillin-H2SO4 and BuOH-HCl methods. The Fr. 5 has the highest proanthocyanidin content (86.00±6.74 g%) among all the fractions. Fr. 6-2 was identified as (+)-catechin by LC-MS analysis. The antioxidant activities of the proanthocyanidin were evaluated by total phenolic contents, DPPH radical scavenging, and FRAP assays. Fr. 8 shows the strongest antioxidant activities with high proanthocyanidin content. The wild grape seed containing fairly high amounts of proanthocyanidin could be utilized as a natural antioxidant material.