Sasanquasaponin protects rat cardiomyocytes against oxidative stress induced by anoxia-reoxygenation injury

Systemic Analyses of Anti-Cell-Senescence Active Compounds in Camellia Sect. Chrysantha Chang and Their Mechanisms

Aging is an irreversible pathophysiological process for all organisms. The accumulation of senescent cells in pathological sites or tissues is recognized as the major cause of diseases and disorders during the aging process. Small molecules that reduce senescent cell burdens have gained increasing attention as promising intervention therapeutics against aging, but effective anti-senescence agents remain rare. Camellia Sect. Chrysantha Chang is documented as a traditional Chinese herbal medicine used by ethnic groups for many medical and health benefits, but its effect on aging is unclear. Here, we investigated the anti-senescence potential of eight C. Sect. Chrysantha Chang species. The results show that ethyl acetate fractions from these C. Sect. Chrysantha Chang species were able to delay the senescence of H9c2 cardiomyocytes except for C. pingguoensis (CPg). N-butanol fractions of C. multipetala (CM), C. petelotii var. grandiflora (CPt), and C. longzhouensis (CL) showed a senescent cell clearance effect by altering the expression levels of senescent-associated marker genes in the DNA-damage response (DDR) pathway and the senescent cell anti-apoptotic pathway (SCAPs). By using UPLC-QTOF-MS-based non-targeted metabolomics analyses, 27 metabolites from Sect. Chrysantha species were putatively identified. Among them, high levels of sanchakasaponin C and D in CM, CPt, and CL were recognized as the key bioactive compounds responsible for senescent cell clearance. This study is the first to disclose and compare the anti-cell-senescence effect of a group of C. Sect. Chrysantha Chang, including some rare species. The combination of senescent markers and metabolomics analyses helped us to reveal the differences in chemical constituents that target senescent cells. Significantly, contrary to the C. chrysantha var. longistyla (CCL), which is widely cultivated and commercialized for tea drinks, CM, CPt, and CL contain unique chemicals for managing aging and aging-related diseases. The results from this study provide a foundation for species selection in developing small-molecule-based drugs to alleviate diseases and age-related dysfunctions and may potentially be useful for advancing geroscience research.

Sasanquasaponin from Camellia oleifera Abel Exerts an Anti-Inflammatory Effect in RAW 264.7 Cells via Inhibition of the NF-κB/MAPK Signaling Pathways

Sasanquasaponin (SQS), a secondary metabolite that is derived from Camellia seeds, reportedly possesses notable biological properties. However, the anti-inflammatory effects of SQS and its underlying mechanisms remain poorly explored. Herein, we aimed to investigate the anti-inflammatory properties of SQS against lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 cells, focusing on the nuclear factor-κB (NF-κB) and MAPK signaling pathways. SQS was isolated using a deep eutectic solvent and D101 macroporous adsorption resin and analyzed using high-performance liquid chromatography. The viability of LPS-stimulated RAW264.7 was assessed using the CCK-8 assay. The presence of reactive oxygen species (ROS) was evaluated using 2',7'-dichlorofluorescein-diacetate. The expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) were detected using reverse transcription-quantitative PCR and ELISA. Western blot was performed to analyze the protein expression of LPS-induced RAW264.7 cells. Herein, SQS exhibited anti-inflammatory activity: 30 μg/mL of SQS significantly reduced ROS generation, inhibited the LPS-induced expression of iNOS and COX-2, and attenuated the production of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. The anti-inflammatory activity was potentially mediated by inhibiting the phosphorylation of IκBα and p65 in the NF-κB signaling pathway and the phosphorylation of ERK and JNK in the MAPK signaling pathway. Accordingly, SQS could inhibit inflammation in LPS-induced RAW264.7 cells by suppressing the NF-κB and MAPK signaling pathways. This study demonstrated the potential application of SQS as an anti-inflammatory agent.

Multi-stress resilience in plants recovering from submergence

Submergence limits plants' access to oxygen and light, causing massive changes in metabolism; after submergence, plants experience additional stresses, including reoxygenation, dehydration, photoinhibition and accelerated senescence. Plant responses to waterlogging and partial or complete submergence have been well studied, but our understanding of plant responses during post-submergence recovery remains limited. During post-submergence recovery, whether a plant can repair the damage caused by submergence and reoxygenation and re-activate key processes to continue to grow, determines whether the plant survives. Here, we summarize the challenges plants face when recovering from submergence, primarily focusing on studies of Arabidopsis thaliana and rice (Oryza sativa). We also highlight recent progress in elucidating the interplay among various regulatory pathways, compare post-hypoxia reoxygenation between plants and animals and provide new perspectives for future studies.

Sasanquasaponin inhibited epithelial to mesenchymal transition in prostate cancer by regulating the PI3K/Akt/mTOR and Smad pathways

CONTEXT

Sasanquasaponin (SQS) is a commonly used traditional Chinese medicine proved to have a wide range of pharmacological functions.

OBJECTIVE

The objective of this study is to explore the effect and underlying mechanism of SQS in the treatment of prostate cancer (PC).

MATERIALS AND METHODS

PC cell lines (22Rv1 and PC-3) were treated with SQS (0, 0.5, 1, 2, and 4 μM) for 12 or 24 h. The viability of cells was evaluated, while the mRNA and protein levels of epithelial to mesenchymal transition (EMT)-related genes in PC cell lines were measured (Groups: Control, TGF-β1, TNF-α, TGF-β1 + TNF-α, and TGF-β1 + TNF-α + SQS). The migration and invasion abilities of PC cell lines were evaluated (Groups: Control, SQS). Finally, the antitumour effect of SQS (25, 50,100, and 200 mg/kg) in BALB/c nude mice (6 weeks, 18-20 g) was evaluated (Groups: Control, Vehicle, 25, 50,100, and 200 mg/kg SQS). The study duration was 1 month.

RESULTS

SQS inhibited the viability and the number of colonies of 22Rv1 or PC-3 cells. The IC₅₀ of SQS of 12 and 24 h in these two cells was 3.25, 1.82, 4.76, and 4.70 μM, respectively. SQS inhibited the adhesion, migration, and invasion of PC cells. It also inhibited the expression of EMT-related markers of PC cells. The PI3K/Akt/mTOR and Smad2/3 signalling pathways were activated in the process of EMT, and SQS could significantly reduce the activation of the PI3K/Akt/mTOR and Smad2/3 pathways. Finally, SQS inhibited the growth of xenograft tumours in vivo.

CONCLUSIONS

SQS inhibited EMT in PC by regulating the PI3K/Akt/mTOR and Smad pathways.

Saponins in Chinese Herbal Medicine Exerts Protection in Myocardial Ischemia-Reperfusion Injury: Possible Mechanism and Target Analysis

Myocardial ischemia is a high-risk disease among middle-aged and senior individuals. After thrombolytic therapy, heart tissue can potentially suffer further damage, which is called myocardial ischemia-reperfusion injury (MIRI). At present, the treatment methods and drugs for MIRI are scarce and cannot meet the current clinical needs. The mechanism of MIRI involves the interaction of multiple factors, and the current research hotspots mainly include oxidative stress, inflammation, calcium overload, energy metabolism disorders, pyroptosis, and ferroptosis. Traditional Chinese medicine (TCM) has multiple targets and few toxic side effects; clinical preparations containing Panax ginseng C. A. Mey., Panax notoginseng (Burk.) F. H. Chen, Aralia chinensis L., cardioprotection, and other Chinese herbal medicines have been used to treat patients with coronary heart disease, angina pectoris, and other cardiovascular diseases. Studies have shown that saponins are the main active substances in TCMs containing Panax ginseng C. A. Mey., Panax notoginseng (Burk.) F. H. Chen, Aralia chinensis L., and Radix astragali. In the present review, we sorted the saponin components with anti-MIRI effects and their regulatory mechanisms. Each saponin can play a cardioprotective role via multiple mechanisms, and the signaling pathways involved in different saponins are not the same. We found that more active saponins in Panax ginseng C. A. Mey. are mainly dammar-type structures and have a strong regulatory effect on energy metabolism. The highly active saponin components of Aralia chinensis L. are oleanolic acid structures, which have significant regulatory effects on calcium homeostasis. Therefore, saponins in Chinese herbal medicine provide a broad application prospect for the development of highly effective and low-toxicity anti-MIRI drugs.

Sasanquasaponin induces increase of Cl‑/HCO3‑ exchange of anion exchanger 3 and promotes intracellular Cl‑ efflux in hypoxia/reoxygenation cardiomyocytes

Anion exchanger 3 (AE3) is known to serve crucial roles in maintaining intracellular chloride homeostasis by facilitating the reversible electroneutral exchange of Cl‑ for HCO3‑ across the plasma membrane. Our previous studies reported that sasanquasaponin (SQS) can inhibit hypoxia/reoxygenation (H/R)‑induced elevation of intracellular Cl‑ concentration ([Cl‑]i) and elicit cardioprotection by favoring Cl‑/HCO3‑ exchange of AE3. However, the molecular basis for SQS‑induced increase of Cl‑/HCO3‑ exchange of AE3 remains unclear. The present study demonstrated that SQS activates protein kinase Cε (PKCε) and stimulates the phosphorylation of AE3 in H9c2 cells. Notably, SQS‑induced AE3 phosphorylation was blocked by the PKCε selective inhibitor εV1‑2, and a S67A mutation of AE3, indicating that SQS could promote phosphorylation of Ser67 of AE3 via a PKCε‑dependent regulatory signaling pathway. Additionally, both inhibition of PKCε by εV1‑2 and S67A mutation of AE3 eradicated the SQS‑induced increase of AE3 activity, reversed the inhibitory effect of SQS on H/R‑induced elevation of [Cl‑]i, Ca2+ overload and generation of reactive oxygen species, and eliminated SQS‑induced cardioprotection. In conclusion, PKCε‑dependent phosphorylation of serine 67 on AE3 may be responsible for the increase of Cl‑/HCO3‑ exchange of AE3 and intracellular chloride efflux by SQS, and contributes to the cardioprotection of SQS against H/R in H9c2 cells.

Sasanquasaponin-induced cardioprotection involves inhibition of mPTP opening via attenuating intracellular chloride accumulation

Sasanquasaponin (SQS) has been reported to elicit cardioprotection by suppressing hypoxia/reoxygenation (H/R)-induced elevation of intracellular chloride ion concentration ([Cl^-]_i). Given that the increased [Cl^-]_i is involved to modulate the mitochondrial permeability transition pore (mPTP), we herein sought to further investigate the role of mPTP in the cardioprotective effect of SQS on H/R injury. H9c2 cells were incubated for 24h with or without 10μM SQS followed by H/R. The involvement of mPTP was determined with a specific mPTP agonist atractyloside (ATR). The results showed that SQS attenuated H/R-induced the elevation of [Cl^-]_i, accompanied by reduction of lactate dehydrogenase release and increase of cell viability. Moreover, SQS suppressed mPTP opening, and protected mitochondria, as indicated by preserved mitochondrial membrane potential and respiratory chain complex activities, decreased mitochondrial reactive oxygen species generation, and increased ATP content. Interestingly, extracellular Cl^--free condition created by replacing Cl^- with equimolar gluconate resulted in a decrease in [Cl^-]_i and induced protective effects similar to SQS preconditioning, whereas pharmacologically opening of the mPTP with ATR abolished all the protective effects induced by SQS or Cl^--free, including suppression of mPTP opening, maintenance of mitochondrial membrane potential, and subsequent improvement of mitochondrial function. The above results allow us to conclude that SQS-induced cardioprotection may be mediated by preserving the mitochondrial function through preventing mPTP opening via inhibition of H/R-induced elevation of [Cl^-]_i.

Sasanquasaponin promotes cellular chloride efflux and elicits cardioprotection via the PKCε pathway

Sasanquasaponin (SQS) is an active component of Camellia oleifera Abel. A recent study by our group demonstrated that SQS was able to inhibit ischemia/reperfusion‑induced elevation of the intracellular chloride ion concentration ([Cl‑]i) and exerted cardioprotective effects; however, the underlying intracellular signal transduction mechanisms have yet to be elucidated. As protein kinase C ε (PKCε) is able to mediate Cl‑ homeostasis, the present study investigated its possible involvement in the effects of SQS on cardiomyocytes subjected to ischemia/reperfusion injury. Cardiomyocytes were pre‑treated with or without SQS or SQS plus εV1‑2, a selective PKCε inhibitor, followed by simulated ischemia/reperfusion (sI/R). The effects on cell viability, PKCε phosphorylation levels, [Cl‑]i, mitochondrial membrane potential and reactive oxygen species (ROS) production were assessed using an MTS assay, western blot analysis, colorimetric assays and flow cytometry. The results revealed that treatment with SQS prior to sI/R increased the viability of cardiomyocytes, and efficiently attenuated lactate dehydrogenase and creatine phosphokinase release induced by sI/R. In addition, SQS promoted PKCε phosphorylation and inhibited sI/R‑induced elevation of [Cl‑]i, paralleled by the attenuation of mitochondrial membrane potential loss and ROS generation. However, when the cardiomyocytes were treated with εV1‑2 prior to SQS pre‑conditioning, the cardioprotection induced by SQS was reduced and the inhibitory effects of SQS on sI/R‑induced elevation of [Cl‑]i, production of ROS and loss of mitochondrial membrane potential were also attenuated. These findings indicated that SQS may inhibit sI/R‑induced elevation of [Cl‑]i through the PKCε signaling pathway to elicit cardioprotection in cultured cardiomyocytes.

Kaempferol protects cardiomyocytes against anoxia/reoxygenation injury via mitochondrial pathway mediated by SIRT1

Mitochondria-mediated apoptosis is a critical mechanism of anoxia/ reoxygenation (A/R)-induced injury in cardiomyocytes. Kaempferol (Kae) is a natural polyphenol and a type of flavonoid, which has been demonstrated to protect myocardium against ischemia/reperfusion (I/R) injury. However, the mechanism is still not fully elucidated. We hypothesize that Kae may improve the mitochondrial function during I/R injury via a potential signal pathway. In this study, an in vitro I/R model was replicated on neonatal rat primary cardiomyocytes by A/R treatment. Cell viability was monitored by the 3-(4,5-dimethylthiazol- 2-yl)-5-(3- carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium (MTS) assay. The levels of intracellular reactive oxygen species, mitochondrial membrane potential (Δψm) and apoptosis were determined by flow cytometry. Protein expression was detected by Western Blotting. mPTP opening and the activity of caspase-3 were measured by colorimetric method. The results showed that Kae effectively enhanced the cell viability and decreased the LDH release in cardiomyocytes subjected to A/R injury. Kae reduced the A/R-induced reactive oxygen species generation, the loss of Δψm, and the release of cytochrome c from mitochondria into cytosol. Kae inhibited the A/R-stimulated mPTP opening and activation of caspase-3, and ultimate decrease in cardiomyocytes apoptosis. Furthermore, we found Kae up-regulated Human Silent Information Regulator Type 1 (SIRT1) expression, indicating SIRT1 signal pathway likely involved the cardioprotection of Kae. Sirtinol, a SIRT1 inhibitor, abolished the protective effect of Kae in cardiomyocytes subjected to A/R. Additionally, Kae significantly increased the expression of Bcl-2. Thus, we firstly demonstrate that Kae protects cardiomyocytes against A/R injury through mitochondrial pathway mediated by SIRT1.

Silencing of angiotensin‑converting enzyme by RNA interference prevents H9c2 cardiomyocytes from apoptosis induced by anoxia/reoxygenation through regulation of the intracellular renin-angiotensin system

Inhibition of the angiotensin‑converting enzyme (ACE) attenuated apoptotic cardiomyocytes induced by ischemic reperfusion (I/R). However, it is difficult to evaluate the effects of inhibition of the intracellular ACE in vivo. The objective of this study was to determine whether the apoptosis in H9c2 cardiomyocytes following anoxia/reoxygenation (A/R) would be improved by the silencing of intracellular ACE by RNA interference (RNAi). H9c2 cardiomyocytes were subjected to A/R 48 h following transfection with ACE-shRNA plasmid. The results showed that the gene silencing of intracellular ACE significantly inhibited the decrease of cell viability and the increase of apoptotic H9c2 cardiomyocytes undergoing A/R. Additionally, the gene silencing of intracellular ACE significantly promoted the expression of ACE2, decreased caspase‑3 activity and Bax levels, and enhanced the expression of Bcl‑2 in H9c2 cardiomyocytes subjected to A/R. The results suggest that the gene silencing of intracellular ACE holds great potential in the treatment of cardiomyocyte apoptosis following I/R injury through the regulation of the intracellular renin‑angiotensin system, thereby regulating the intrinsic pathway of apoptosis.

Antimicrobial activity of saponin-rich fraction from Camellia oleifera cake and its effect on cell viability of mouse macrophage RAW 264.7

BACKGROUND

As a by-product of oil production, several million tons of Camellia oleifera cake is discarded every year in China. The aim of this study was to evaluate the antimicrobial activity of a saponin-rich fraction isolated from C. oleifera cake and investigate its effect on the cell viability of RAW 264.7, a macrophage-like cell line present in almost all mouse tissues.

RESULTS

The saponin-rich fraction was isolated from C. oleifera cake in several steps and had a saponin content of 95.42 ± 0.10% (w/w). It showed significant inhibitory activity against the bacteria Staphylococcus aureus, Escherichia coli and Bacillus subtilis and the fungi Mucor racemosus, Aspergillus oryzae, Rhizopus stolonifer, Saccharomyces cerevisiae and Penicillium glaucum, with minimum inhibitory concentrations of 31.3, 31.3, 62.5, 250, 250, 250, 31.3 and 125 µg ml(-1) respectively. In addition, mouse macrophage RAW 264.7 pretreated with the saponin-rich fraction (80-200 µg mL(-1) ) exhibited a significant loss of cell viability in a dose-dependent manner.

CONCLUSION

These results may be useful for the future application of saponins from C. oleifera cake. However, the potential use of the saponin-rich fraction as an antimicrobial agent should be decided according to the target micro-organisms in order to avoid causing harm in humans.

Sasanquasaponin up-regulates anion exchanger 3 expression and elicits cardioprotection via NO/RAS/ERK1/2 pathway

We have shown recently that sasanquasaponin (SQS) can inhibit ischemia/reperfusion-induced elevation of intracellular Cl(-) concentration ([Cl(-)](i)) and elicit cardioprotection by up-regulating anion exchanger 3 (AE(3)) expression. In the present study, we futher analysed the intracellular signal transduction pathways by which SQS up-regulates AE(3) expression and elicits cardioprotection. Cardiomyocytes were incubated for 24 h with or without 10 µmol/L SQS, followed by simulated ischemia/reperfusion (sI/R). NO formation, Ras activity, and extracellular-regulated kinase 1/2 (ERK1/2) phosphorylation were measured appropriately. We showed that SQS pretreatment efficiently attenuated viability loss and lactate dehydrogenase leakage induced by sI/R in cardiomyocytes. Moreover, SQS induced NO production and promoted Ras activation, which futher promoted extracellular-regulated kinase 1/2 (ERK1/2) phosphorylation. These effects were paralleled by an increase in AE(3) expression. However, when the cardiomyocytes were treated with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide (c-PTIO; an NO scavenger), S-trans-trans-farnesylthiosalicylic acid (FTS) (a Ras inhibitor), U0126 (an ERK1/2 inhibitor), respectively, the increase in AE(3) expression occurring during SQS pretreatment was almost completely abolished and, as a result, SQS-induced cardioprotection was prevented. Our findings indicate that SQS might up-regulate AE(3) expression through NO/Ras/ERK1/2 signal pathway to elicit cardioprotection in cultured cardiomyocytes.

Resveratrol, a polyphenol phytoalexin, protects cardiomyocytes against anoxia/reoxygenation injury via the TLR4/NF-κB signaling pathway

Previous studies indicate resveratrol pretreatment can protect cardiomyocytes. However, it is largely unknown whether resveratrol protects cardiomyocytes when applied at reperfusion. The purpose of this study was to investigate whether resveratrol given at reoxygenation could protect cardiomyocytes under the anoxia/reoxygenation (A/R) condition and to examine the underlying mechanism. In this study, primary cultures of neonatal rat cardiomyocytes were randomly distributed into three groups: control group, A/R group (cultured cardiomyocytes were subjected to 3 h anoxia followed by 2 h reoxygenation), and the resveratrol group (cardiomyocytes were subjected to 3 h anoxia/2 h reoxygenation, and 5, 10 or 20 μM resveratrol was applied 5 min after reoxygenation). In order to evaluate cardiomyocyte damage, cell viability, lactate dehydrogenase (LDH) release, caspase-3 activity, and apoptosis were analyzed by the cell counting kit (CCK)-8 assay, colorimetric method and flow cytometry, respectively. The mRNA and protein expression of Toll-like receptor 4 (TLR4) were detected by quantitative real-time PCR and western blot analysis. Nuclear factor-κB (NF-κB) p65 protein and I-κBα protein levels were also examined by western blot analysis. The levels of proinflammatory cytokines in the culture medium were assessed by enzyme-linked immunosorbent assay. We found that resveratrol prevented a reduction in cell viability, decreased the amount of LDH release, attenuated apoptotic cells and decreased caspase-3 activity induced by A/R in cardiomyocytes. Furthermore, resveratrol treatment significantly attenuated the TLR4 expression, inhibited NF-κB activation and reduced the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β caused by A/R injury in the culture medium. Treatment with resveratrol shortly after the onset of reoxygenation improves cell survival and attenuates A/R-induced inflammatory response. This protection mechanism is possibly related to the TLR4/NF-κB signaling pathway.

Foam properties and detergent abilities of the saponins from Camellia oleifera

The defatted seed meal of Camellia oleifera has been used as a natural detergent and its extract is commercially utilized as a foam-stabilizing and emulsifying agent. The goal of this study was to investigate the foam properties and detergent ability of the saponins from the defatted seed meal of C. oleifera. The crude saponin content in the defatted seed meal of C. oleifera was 8.34 and the total saponins content in the crude saponins extract was 39.5% (w/w). The foaming power of the 0.5 crude saponins extract solution from defatted seed meal of C. oleifera was 37.1 of 0.5 SLS solution and 51.3% to that of 0.5% Tween 80 solution. The R5 value of 86.0% represents good foam stability of the crude saponins extracted from the defatted seed meal of the plant. With the reduction of water surface tension from 72 mN/m to 50.0 mN/m, the 0.5% crude saponins extract solution has wetting ability. The sebum-removal experiment indicated that the crude saponins extract has moderate detergency. The detergent abilities of the saponins from C. oleifera and Sapindus mukorossi were also compared.

Ganoderma atrum polysaccharide protects cardiomyocytes against anoxia/reoxygenation-induced oxidative stress by mitochondrial pathway

It is now well established that oxidative stress plays a causative role in the pathogenesis of anoxia/reoxygenation (A/R) injury. Ganoderma atrum polysaccharide (PSG-1), the most abundant component isolated from G. atrum, has been shown to possess potent antioxidant activity. The goals of this study were to investigate the effect of PSG-1 against oxidative stress induced by A/R injury and the possible mechanisms in cardiomyocytes. In this work, primary cultures of neonatal rat cardiomyocytes pretreated with PSG-1 were subjected to A/R and subsequently monitored for cell viability by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The levels of intracellular reactive oxygen species (ROS), apoptosis, and mitochondrial membrane potential (Deltapsi(m)) were determined by flow cytometry. Western blot analysis was used to measure the expression of cytochrome c, Bcl-2 family, and manganese superoxide dismutase (MnSOD) proteins, and the activities of caspase-3 and caspase-9 were determined by a colorimetric method. The results showed that PSG-1 protected against cell death caused by A/R injury in cardiomyocytes. PSG-1 reduced the A/R-induced ROS generation, the loss of mitochondrial membrane potential (Deltapsi(m)), and the release of cytochrome c from the mitochondria into cytosol. PSG-1 inhibited the A/R-stimulated activation of caspase-9 and caspase-3 and alteration of Bcl-2 family proteins. Moreover, PSG-1 significantly increased the protein expression of MnSOD in cardiomyocytes. These findings suggest that PSG-1 significantly attenuates A/R-induced oxidative stress and improves cell survival in cardiomyocytes through mitochondrial pathway.

Quantitative thin layer chromatographic analysis of the saponins in tea seed meal

INTRODUCTION

The defatted seed meal of Camellia oleifera Abel., which contains saponins, is used extensively in aquaculture to eliminate unwanted fish and harmful insects during the cultivation of prawns, and as a molluscicide to control Pomacea canaliculata Lamarck. For the quality control of such tea seed meal products, a method for the determination of saponin content is required.

OBJECTIVE

To develop a simple, sensitive and specific method for the quantitative determination of saponins in tea seed meal using high-performance thin layer chromatography and densitometry.

METHODOLOGY

Powdered tea seed meal samples were extracted with methanol, filtered, evaporated to dryness and the residue taken up in methanol. Samples, together with methanolic solutions of saponin standard, were analysed by HPTLC on silica gel layers eluted with ethyl acetate:methanol:water (6:3:1.5, v/v/v) and detected at 214 nm. The amounts of saponins were determined from the respective calibration curves obtained by plotting the concentrations of saponin standard against peak area.

RESULTS

Tea saponin peaks were detected at about R(f )0.40. Good linearity was observed in the range of 0.9-22.2 microg/spot with a correlation coefficient of 0.9978. The limits of detection and quantification were 0.87 and 2.90 microg/spot, respectively. The content of tea saponins in 10 tested samples was found to be between 13.1 and 21.1% w/w.

CONCLUSION

The assay proved to be a specific, sensitive and inexpensive method for the quality control of saponins in tea seed meal.