Comparison in Antioxidant Potential and Concentrations of Selected Bioactive Ingredients in Fruits of Lesser-Known Species.

Fruits with a high content of biologically active compounds are essential in preventing many diseases. Therefore, the interest in searching for and testing new plant sources for bioactive constituents remains strong. Although many publications on individual species exist, their results are difficult to compare directly due to varying methods and conditions of analysis. Only a few studies have investigated many different species in a single analysis. Therefore, we examined and compared 21 different genotypes, using various measurement methods for total phenolic content (TPC) (Folin-Ciocalteu, FBBB), total antioxidant capacity (ABTS, FRAP, DPPH), and the HPLC technique for the total ascorbate concentration in freshly harvested fruits. One-way ANOVA, Principal Component Analysis, and Pearson Correlation were used to analyse and compare the results. The tested samples showed significant differences in TPC, ascorbate content, and antioxidant capacity. The correlation between the content of bioactive compounds and antioxidant capacity depended on the analytical methods, with results obtained using the FRAP test being the most strongly correlated. Due to higher levels of polyphenols, ascorbate, and antioxidant potential, the most promising species for further evaluation appear to be Chaenomeles × californica, Actinidia kolomikta, Mespilus germanica, and ×Sorboaronia fallax.

Bioassay-guided Fractionation of Anti-Leishmania amazonensis Extracts from Ampelozizyphus amazonicus by High-speed Countercurrent Chromatography.

Ampelozizyphus amazonicus Ducke, known as "saracura-mirá" in the Amazon rainforest, is valued for its traditional use in malaria prevention and treatment. The plant's roots and bark are employed for these purposes, while the wood is often overlooked. Given the global importance of leishmaniasis, research focused on A. amazonicus anti-Leishmania amazonensis potential. The ethyl acetate extract from the bark (EAEB) exhibited the most effective inhibition of intracellular amastigote growth with IC50 7.0 µg.mL-1 but showed high toxicity (CC50 9.0 µg.mL-1). The wood ethanol (EW) and ethyl acetate (EAEW) extracts demonstrated promising results against L. amazonensis with IC50 15.8 µg.mL-1 and 10.0 µg.mL-1, CC50 50.5 µg.mL-1 and 22.7 µg.mL-1, respectively. High-speed countercurrent chromatography combined with mass spectrometry  off-line detection was employed for the bioassay-guided fractionation of EAEB and EAEW using HEMWat as solvent system. These extracts showed to be rich in saponins and triterpenes, besides minor glycosylated flavonoids. HSCCC was effective in obtaining high purity fractions, leading to the identification of a di-glycosylated triterpene saponin from EAEB, and melaleucic acid from EAEW. These findings highlight A. amazonicus as a potential source for developing new therapeutic alternatives for leishmaniasis and HSCCC as a technique enabling better separation efficiency of complex saponin matrices.

A new anti-inflammatory lupane in Ziziphus jujuba (L.) Gaertn. var. hysudrica Edgew.

Objectives: To investigate extracts of the stem bark of Ziziphus jujuba (L.) Gaertn. var. hysudrica Edgew. (Rhamnaceae) for anti-inflammatory activity and isolate the active principle(s). Methods: The dry powder was macerated separately in three types of solvents to prepare methanol extract (ME), ethyl acetate extract (EE), and chloroform extract (CE). Following in vitro anti-inflammatory screening, the most active extract was selected to isolate the active compound. Both, the active extract and isolated compound were further tested on rats using the carrageenan-induced inflammation model. The blood and paw tissue were subjected to qPCR, and histopathology, respectively. Key findings: CE showed comparatively higher anti-inflammatory activity (85.0-95.0 %) in all in vitro assays, except the heat-induced membrane stabilization model (p < 0.05), and upon column chromatography, it yielded a pure crystalline compound. The compound was a pentacyclic triterpenoid (Lupane), named as hydroxymethyl (3ß)-3-methyl-lup-20(29)-en-28-oate (Hussainate). CE (500 mg/kg) and Hussainate (1.0 mg/kg) reduced edema in 5 h after carrageenan administration. The activity of Hussainate was found to be comparable to that of dexamethasone (standard). The possible activity mechanism was the downregulation of tumor necrosis factor-alpha (TNF-α), cyclooxygenase-2 (COX-II), NF-κB, and IL-1ß. Conclusions: This study reveals that chloroform extract of the stem's bark of Z. jujuba may be used to prepare standardized anti-inflammatory herbal products using Hussainate as an active analytical marker. Hussainate may be used as a lead to develop anti-inflammatory drugs.

The complete chloroplast genome sequence of Rhamnella wilsonii Schneid (Rhamnaceae).

Rhamnella wilsonii Schneid 1914 is a member of the Rhamnaceae and endemic to China. In this study, the complete chloroplast genome of R. wilsonii was sequenced and assembled. The complete chloroplast genome was 160,049 bp in length, including a pair of inverted repeats (IRs) of 26,502 bp, one large single copy (LSC) region of 88,274 bp and one small single copy (SSC) region of 18,771 bp. The genome contained 129 genes, including 8 rRNA genes, 37 tRNA genes and 84 protein-coding genes. The overall GC content of the complete chloroplast genome was 37.15%. The phylogenetic analysis demonstrated that R. wilsonii is closely related to R. martinni. This study provides basic information for further studies on the identification and evolution of R. wilsonii and Rhamnella from genomic perspective.

Molecular Docking Studies and In Vitro Activity of Paliurus spina-christi Mill Extracts as Pancreatic Lipase Inhibitors.

Obesity is a risk factor for the onset of chronic diseases. One of the most promising approaches to treating obesity consists of reducing dietary fat absorption using extracts from plants because they contain phenolic compounds, especially flavonoids. Paliurus spina-christi, belonging to the Rhamnaceae family, is one of the five species belonging to the Paliurus genus. Herein, the aerial parts of the plant were extracted with methanol through the pressurized cyclic solid-liquid extraction using the Naviglio extractor®. The extracts were analyzed with High Performance Thin Layer Chromatography and investigated for their in vitro biological potential. The phytochemical analysis revealed that rutin has been shown to be the most abundant flavonoid component. The best antiradical activity was observed for the fruit extract with an IC50 value of 53.41 ± 1.24 µg/mL. This extract also has a better inhibitory capacity on lipid peroxidation evaluated at a different time of incubation. Potent lipase inhibitor activity of the extract from fruits was also demonstrated with in vitro experiments. This property can be attributed to a direct interaction of main components of P. spina-christi extract with the human pancreatic enzyme as demonstrated by the results of molecular docking experiments conducted on the crystallographic structures of lipase.

Rapid in situ diversification rates in Rhamnaceae explain the parallel evolution of high diversity in temperate biomes from global to local scales.

The macroevolutionary processes that have shaped biodiversity across the temperate realm remain poorly understood and may have resulted from evolutionary dynamics related to diversification rates, dispersal rates, and colonization times, closely coupled with Cenozoic climate change. We integrated phylogenomic, environmental ordination, and macroevolutionary analyses for the cosmopolitan angiosperm family Rhamnaceae to disentangle the evolutionary processes that have contributed to high species diversity within and across temperate biomes. Our results show independent colonization of environmentally similar but geographically separated temperate regions mainly during the Oligocene, consistent with the global expansion of temperate biomes. High global, regional, and local temperate diversity was the result of high in situ diversification rates, rather than high immigration rates or accumulation time, except for Southern China, which was colonized much earlier than the other regions. The relatively common lineage dispersals out of temperate hotspots highlight strong source-sink dynamics across the cosmopolitan distribution of Rhamnaceae. The proliferation of temperate environments since the Oligocene may have provided the ecological opportunity for rapid in situ diversification of Rhamnaceae across the temperate realm. Our study illustrates the importance of high in situ diversification rates for the establishment of modern temperate biomes and biodiversity hotspots across spatial scales.

The complete plastid genome of Rhamnus leptacantha Schneid. (Rhamnaceae).

Rhamnus leptacantha C.K.Schneid. (1914). is a rare shrub species of the genus Rhamnus. The complete plastid genome of Rhamnus leptacantha was sequenced for the first time in this study. The total length of this genome is 161,248 bp with a large single copy (LSC) region (89,386 bp), a small single copy (SSC) region (19,000 bp), and two inverted repeat regions (IRs, 26,431 bp). A total of 133 functional genes were annotated, including 88 protein-coding genes, 37 tRNA genes and 8 rRNA genes. Plastome of R. leptacantha displayed a conservative structure and gene order. Phylogenetic analysis strongly supported R. leptacantha clustered with other members of genus Rhamnus. This study provides a foundation for further investigation of the complete chloroplast genome in inferring the evolution within the Rhamnaceae family.

Dispersal modes affect Rhamnaceae diversification rates in a differentiated manner.

The evolution of dispersal modes has been proposed to promote the diversification of angiosperms. However, little is known about the relative impact of different dispersal modes on plant diversification. We test the association between dispersal modes and diversification rates using Rhamnaceae, the cosmopolitan buckthorn family, as a model. We found that species with diplochory have the highest diversification rates followed by those with myrmecochory and ballistic dispersal, while lineages dispersed by vertebrates and wind have relatively low diversification rates. The difference in diversification rates may be closely linked to the difference in dispersal distance and ecological interactions implied by each dispersal mode. Species which disperse over larger geographical distances may have much higher speciation rates due to the increased chance of establishing isolated populations due to geological barriers or habitat fragmentation. However, long-distance dispersal may also increase the chance of extinction. By contrast, species with short-distance dispersal modes may have low speciation rates. Complex interactions with the surrounding environment may, however, impact diversification rates positively by increasing plant survival and reproductive success.

Variation in Seed Dormancy of Chaco Seasonally Dry Forest Species: Effects of Seed Traits and Population Environmental Conditions.

The persistence of subtropical seasonally dry forests urgently requires the implementation of ex situ conservation and restoration programs. We studied variation in seed traits and dormancy of six native species growing in seasonally dry Chaco forests of Argentina. We documented high intra- and interspecific variability in seed traits and dormancy. Fresh seeds of Geoffroea decorticans and Parasenegalia visco (Fabaceae) were water-permeable and nondormant (ND), while those of Parkinsonia praecox and Vachellia aroma (Fabaceae) were water-impermeable and had physical dormancy (PY). Seeds of Schnopsis lorentzii (Anacardiaceae) and Sarcomphalus mistol (Rhamnaceae) were water-permeable and had physiological dormancy (PD). Mechanical and chemical scarification were the most effective methods to break PY, and dry storage for 3 months was effective in breaking PD. Seeds of large-seeded species were ND or had PD, and those of small-seeded species had PY. Species inhabiting moist habitats had ND seeds, whereas those from seasonally dry habitats had seeds with PY or PD. These results suggest that seed traits and dormancy are species-specific and that intraspecific variation in seed traits is likely associated with high phenotypic plasticity of species in response to local environmental heterogeneity. These findings should be considered at the time of implementation of conservation techniques and for seed sourcing decisions for restoration.

Isolation and identification of novel selective antitumor constituents, sidrin and sidroside, from Zizyphus spina-christi.

Background: The leaves of Zizyphus spina-christi (L.) Willd contain several compounds exhibiting different pharmacologic activities. However, studies on the cytotoxic activity of these compounds are limited. Objectives: We aimed to investigate and isolate cytotoxic compounds with selective antitumor effects from the leaves of Z. spina-christi using bioassay-guided fractionation of methanol extract. Methods: Powdered, dried leaves were subjected to methanol extraction and fractionated using n-hexane, chloroform, ethyl acetate, and n-butanol. Fractions with positive cytotoxicity against HeLa and THP-1 cell lines were further fractionated and eluted using various concentrations of organic solvents. Active compounds were isolated using different chromatographic methods and their chemical structures were determined using extensive spectroscopic methods, such as 1D NMR (1H NMR, 13C NMR, and DEPT), 2D NMR (COSY, HMBC, and HMQC), HRFAB-MS, and IR. Furthermore, the cytotoxic effects of the isolated compounds were evaluated against 62 tumor cell lines (including HeLa and THP-1) in addition to normal bone marrow cells. Results: The chloroform and aqueous methanol fractions of the leaves showed cytotoxic activity. Two compounds were successfully isolated and named "sidrin" (13-ß-hydroxy-lup-20(30)-ene-2,3-ß-epoxy-28-carboxylate) and "sidroside" (3-O-ß-D-glucopyranosyl-(1-3)-α-L-arabinopyranosyl-jujubogenin-20-O-α-L-rhamnopyranoside). Sidrin exhibited cytotoxic activity against the human leukemia (Hl-60, RPMI-8226), lung cancer (A549, EKVX), breast cancer (BT-549, MDA-MB-231/ATCC), colon cancer (KM12), melanoma (M14, SK-MEL-5), and central nervous system (CNS) cancer (SF-295) cell lines, and selectivity was observed against the Hl-60, EKVX, BT-549, KM12, and SF-295 cell lines. In addition, sidrin was more active than sidroside and doxorubicin against the Hl-60 and EKVX cell lines. In contrast, sidrin had a similar effect to doxorubicin against the BT-549 and renal cancer (UO-31) cell lines. Sidroside was more selective against the leukemia (CCRF-CEM, MOLT-4), lung cancer (HOP-92, NCI-H322M), breast cancer (MDA-MB-468), melanoma (LOX IMVI), CNS cancer (SNB-19), ovarian cancer (OVCAR-8), renal cancer (UO-31, RXF 393), and prostate cancer (PC-3) cell lines. Both compounds exhibited similar activity against the breast cancer (MDA-MB-231, T-47D), colon cancer (HCC-2998, HCT-116), ovarian cancer (OVCAR-3), renal cancer (UO-31, 786-0, and SN 12C) cell lines. Normal bone marrow cells were unaffected at the same concentrations of sidrin and sidroside applied to tumor cells. Conclusions: These results suggest tumor-selective cytotoxicity of sidrin and sidroside.

Anti-SARS-CoV-2 Activity of Ampelozizyphus amazonicus (Saracura-Mirá): Focus on the Modulation of the Spike-ACE2 Interaction by Chemically Characterized Bark Extracts by LC-DAD-APCI-MS/MS.

Traditional medicine shows several treatment protocols for COVID-19 based on natural products, revealing its potential as a possible source of anti-SARS-CoV-2 agents. Ampelozizyphus amazonicus is popularly used in the Brazilian Amazon as a fortifier and tonic, and recently, it has been reported to relieve COVID-19 symptoms. This work aimed to investigate the antiviral potential of A. amazonicus, focusing on the inhibition of spike and ACE2 receptor interaction, a key step in successful infection. Although saponins are the major compounds of this plant and often reported as its active principles, a polyphenol-rich extract was the best inhibitor of the spike and ACE2 interaction. Chemical characterization of A. amazonicus bark extracts by LC-DAD-APCI-MS/MS before and after clean-up steps for polyphenol removal showed that the latter play an essential role in maintaining this activity. The effects of the extracts on viral replication were also assessed, and all samples (aqueous and ethanol extracts) demonstrated in vitro activity, inhibiting viral titers in the supernatant of Calu-3 cells after 24 hpi. By acting both in the SARS-CoV-2 cell entry process and its replication, A. amazonicus bark extracts stand out as a multitarget agent, highlighting the species as a promising candidate in the development of anti-SARS-CoV-2 drugs.

The complete chloroplast genome sequence of Berchemia racemosa Siebold & Zucc. (Rhamnaceae), a rare plant species in Korea.

Berchemia racemosa Siebold & Zucc., 1845 is a rare species distributed in restricted areas in the western Korean peninsula. In this study, the complete chloroplast genome (plastome) of B. racemosa was sequenced and assembled by Illumina paired-end sequencing. The plastome of B. racemosa was 161,187 bp in length and was quadripartite in structure, including a large single-copy (LSC) region of 89,503 bp, a small single-copy (SSC) region of 18,214 bp, and two inverted repeats of 26,735 bp. The GC content was 37.2%. The plastome of B. racemosa contains 130 genes, including eight ribosomal RNA (rRNA) genes, 37 transfer RNA (tRNA) genes, and 85 protein-coding genes. Phylogenetic analysis using complete genome sequences showed that B. racemosa is most closely related to Berchemia flavescens.

Revisiting chloroplast genomic landscape and annotation towards comparative chloroplast genomes of Rhamnaceae.

BACKGROUND: Massive parallel sequencing technologies have enabled the elucidation of plant phylogenetic relationships from chloroplast genomes at a high pace. These include members of the family Rhamnaceae. The current Rhamnaceae phylogenetic tree is from 13 out of 24 Rhamnaceae chloroplast genomes, and only one chloroplast genome of the genus Ventilago is available. Hence, the phylogenetic relationships in Rhamnaceae remain incomplete, and more representative species are needed. RESULTS: The complete chloroplast genome of Ventilago harmandiana Pierre was outlined using a hybrid assembly of long- and short-read technologies. The accuracy and validity of the final genome were confirmed with PCR amplifications and investigation of coverage depth. Sanger sequencing was used to correct for differences in lengths and nucleotide bases between inverted repeats because of the homopolymers. The phylogenetic trees reconstructed using prevalent methods for phylogenetic inference were topologically similar. The clustering based on codon usage was congruent with the molecular phylogenetic tree. The groups of genera in each tribe were in accordance with tribal classification based on molecular markers. We resolved the phylogenetic relationships among six Hovenia species, three Rhamnus species, and two Ventilago species. Our reconstructed tree provides the most complete and reliable low-level taxonomy to date for the family Rhamnaceae. Similar to other higher plants, the RNA editing mostly resulted in converting serine to leucine. Besides, most genes were subjected to purifying selection. Annotation anomalies, including indel calling errors, unaligned open reading frames of the same gene, inconsistent prediction of intergenic regions, and misannotated genes, were identified in the published chloroplast genomes used in this study. These could be a result of the usual imperfections in computational tools, and/or existing errors in reference genomes. Importantly, these are points of concern with regards to utilizing published chloroplast genomes for comparative genomic analysis. CONCLUSIONS: In summary, we successfully demonstrated the use of comprehensive genomic data, including DNA and amino acid sequences, to build a reliable and high-resolution phylogenetic tree for the family Rhamnaceae. Additionally, our study indicates that the revision of genome annotation before comparative genomic analyses is necessary to prevent the propagation of errors and complications in downstream analysis and interpretation.

Solid-phase adsorption methodologies of naturally occurring anthraquinones: A review.

INTRODUCTION: Solid-phase extraction applied to plant matrices is nowadays a well-validated technique allowing to concentrate and purify different secondary metabolites. Several classes of phytochemicals have been selectively extracted by this methodology. During the last decade attention has been focused on biologically active anthraquinones from numerous sources like edible, healthy, and medicinal plants. OBJECTIVES: The aim of this review is to provide a detailed literature survey of the solid-phase adsorption methodologies for the extraction of natural anthraquinones reported so far and to discuss and propose future directions in this field of research. MATERIALS AND METHODS: Substructure search was performed in the SciFinder Scholar, PubMed, Medline, and Scopus databases. RESULTS: The first report about application of solid-phase adsorption for the purification of anthraquinones appeared in the literature in 2002. From this date, and in particular during recent years, the most notable examples included the use of chitin- and chitosan-based polymers, of molecularly imprinted polymers, of coated magnetic nanoparticles, of miniaturized matrix solid-phase dispersion, of functionalized resins, of differently structured lamellar solids, and finally of vortex-synchronized matrix solid-phase dispersion. CONCLUSIONS: The herein detailed solid-phase adsorption methodologies are powerful tools to selectively extract natural anthraquinones and/or provide anthraquinone-enriched phytopreparations. Nevertheless, many other important methods have been applied to synthetic anthraquinones (e.g., azo dyes). These could be conveniently employed also for natural anthranoids. Studies in this field are discussed in this review article.

Two new 5(14)-membered type cyclopeptide alkaloids from root bark of Ziziphus spina-christi (L.) Desf.

Six 5(14)-membered ring type of cyclopeptide alkaloids (CPAs), including two undescribed members, 1-hydro,2ß-methoxy-mauritine-A (1) and 1-hydro,2α-methoxy-mauritine-A (2), together with four known compounds, mauritine-A (3), mauritine C (4), amphibine-A (5), and amphibine-E (6), were isolated from the root bark of Ziziphus spina-christi (L.) Desf., Their structures were determined by multiple spectral analyses, including UV, IR, 1D NMR, 2D NMR, EI-MS, HR-EI-MS, FAB-MS and ESI-MS, and by comparison with literature. All six CPAs were tested in vitro for cytotoxicity by three human cancer cell lines (MCF7, H460 and Hela) and a human normal cell line (BJ). None of the compounds showed cytotoxicity towards all tested cell lines.

Three new 8,4'-type oxyneolignans from the seeds of Ziziphus jujuba mill and their antitumor studies.

Ziziphus jujuba Mill. is a deciduous shrub, belonging to the Rhamnaceae family. Phytochemical investigation of Z. jujuba seeds showed the presence of three undescribed 8,4'-type oxyneolignans (1-3). Their structures were elucidated by comprehensive spectroscopic analyses. All isolated compounds were tested for antitumor activity against two human hepatoma cells (Hep3B and HepG2) and exhibited moderate cytotoxicity (IC50: 33.79-49.62 µM).

Triterpenoids from an aqueous extract of the Ziziphus jujuba var. spinosa seeds / 药学学报

Four new triterpenoids, together with six known analogues, were isolated from an aqueous extract of the Ziziphus jujuba var. spinosa seeds, by multiple column chromatographic separation methods using stationary phases of macroporous adsorption resin, MCI resin, normal phase silica gel, Sephadex LH-20, and Toyopearl HW-40C as well as preparative thin-layer chromatography and reversed-phase HPLC. Their structures were determined by spectroscopic data analysis, the new structures were trivially named jujubaceanothoside A (1), 23-epijujuboside A (2), and jujubosides J and K (3 and 4), while the known analogues were identified as jujubosides A-C (5-7) and II (8), alphitolic acid (9), and betulinic acid (10). The structure of 1 was confirmed by single crystal X-ray diffraction.

Protective effect of Hovenia dulcis Thunb. leaf extracts against ethanol-induced DNA damage in SH-SY5Y cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Hovenia dulcis Thunb. has been used as a medicinal herb for the treatment of hepatic diseases and alcohol intoxication. AIM OF THE STUDY: The genotoxic effect and the antigenotoxic potential of ethanolic extract of H. dulcis leaves and its methanolic fraction were evaluated against ethanol-induced damages in SH-SY5Y cells. MATERIALS AND METHODS: The phytochemical analysis and antioxidant activity of H. dulcis extracts were also assessed. In addition, a systems biology analysis was performed to investigate the molecular pathway of action of the H. dulcis leaves compounds. RESULTS: The ethanolic extract and its methanolic fraction presented genotoxicity through comet assay at 0.5 and 0.25 mg/mL. On the other hand, both extracts showed protective action against ethanol at all concentrations. Additionally, an NBT assay was performed and demonstrated an ability of the extracts to reduce superoxide anion formation when SH-SY5Y cells were challenged with ethanol. HPLC analysis indicated the presence of quercitrin, isoquercitrin, and rutin. Further, system biology assays indicated a molecular action pathway, where the compounds from the leaves of H. dulcis, in addition to performing free radical scavenging activity, activate PP2A, and may inhibit the apoptosis pathway activated by ethanol-induced oxidative stress. CONCLUSIONS: This work is important to indicate potential antigenotoxic and antioxidant properties of H. dulcis leaves, and its use can be investigated against DNA damage induced by ethanol.

The complete chloroplast genome of Ziziphus mairei Dode 1908 (Rhamnaceae), an endangered perennial plant in Yunnan, China.

Ziziphus mairei Dode 1908 (Rhamnaceae) is a rare and endangered perennial plant in Yunnan, China. In this study, we sequenced, assembled, and annotated the complete chloroplast genome of Z. mairei. The complete chloroplast genome was a closed circular molecule of 161,546 bp with a typical tetrad structure, containing a large single-copy (LSC) region of 89,252 bp, a small single-copy (SSC) region of 19,364 bp, and a pair of inverted repeat (IR) regions of 26,465 bp. A total of 128 genes have been annotated, including 83 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The GC content is 36.7%. Phylogenetic analysis revealed that Z. mairei is closely related to Z. hajarensis, Z. jujuba, and Z. jujuba var. spinosa. Our results provide useful genetic resources for further studies on the conservation and evolution of Z. mairei.

Ziziphus abyssinica root bark extract ameliorates paracetamol-induced liver toxicity in rats possibly via the attenuation of oxidative stress.

Ziziphus abyssinica root bark is widely used in folk medicine to manage liver diseases, particularly, jaundice but its effect on paracetamol-induced liver toxicity (PILT) has not yet been validated. This study explored the ameliorative effect of ethanolic root bark extract of Ziziphus abyssinica (ZAE) against PILT in rats. The flavonoid and phenolic content of ZAE was evaluated using Folin-Ciocalteau and aluminium trichloride colorimetric methods, respectively. Antioxidant activity of ZAE was determined in vitro by evaluating its ferrous reducing antioxidant capacity (FRAC) as well as DPPH and nitic oxide (NO) radicals scavenging activities. Sprague-Dawley rats were assigned to six groups (n = 6) and administered with normal saline (10 mL/kg, p.o.), N-acetylcysteine (50 mg/kg, i.p.) and ZAE (30, 100, and 300 mg/kg, p.o.) respectively for seven days after which they received paracetamol (PCM, 3000 mg/kg, p.o.). Animals were sacrificed 48 h after paracetamol administration under light anaesthesia and assessed for liver toxicity and oxidative stress. Total flavonoid and phenolic contents of ZAE were 1313.425 µg/mL quercetin equivalence and 268.31 µg/mL gallic acid equivalence respectively. ZAE exhibited marked FRAC as well as DPPH and NO radical scavenging activities with IC50s of 80.41 ± 1.56, 67.56 ± 1.11 and 7.11 ± 1.48 µg/mL respectively. ZAE and N-acetylcysteine significantly (p < 0.05) reduced the paracetamol-mediated elevation of serum total bilirubin, proteins and activity of liver enzymes (AST, ALP, and ALT). Similarly, ZAE increased hepatic glutathione, total thiols and catalase activity of the paracetamol intoxicated rats. Morphological changes associated with the paracetamol hepatotoxicity were also ameliorated by ZAE. Overall, the hepatoprotective effect of ZAE may be related to its antioxidant property.