Plant Growth Regulators, Light and Temperature Influenced Micropropagation and Successful Field Establishment of Vernonia amygdalina Del.

Vernonia amygdalina Del. is a tropical species susceptible to frost which is an annual phenomenon of the winter season of the Eastern Cape. Limited populations of the species arc in the province dieback during the winter period, thereby making large scale cultivation through conventional vegetative propagation impossible. In our effort to increasing the population of the species within the province, a micropropagation approach through tissue culture teehnology was employed. Two growth regulators （BAP ＆ NAA） were tested at four levels of concentration under continuous light and dark conditions. Plantlets were subsequently transferred to the field after acclimatization at different temperature conditions. The result of the study showed that BAP generally performs better than NAA for callus induction under continuous darkness, while direct micropropagation of shoot under continuous light condition at I mg L^-1BAP showed the best result. To achieve greater success for the rapid multiplication of the species, this study further demonstrates that the optimum temperature range for acclimatizing the species prior to the transfer of the plantlet to the field is between 23 ±3 ℃.

Phytochemical screening and antibacterial activities of Momordica charantia and Vernonia amygdalina extracts on some selected enteric isolates

Background:This research focuses on herbal medicine,an ancient healthcare practice,exploring the antibacterial attributes of fresh and dried leaf extracts from Momordica charantia(commonly known as Bitter melon)and Vernonia amygdalina(Bitter leaf).The study specifically investigates their effects on different bacterial strains associated with gastroenteritis.Methods:Four enteric bacterial isolates-Klebsiella pneumoniae,Salmonella typhi,Escherichia coli,and Proteus mirabilis-were obtained from the Medical Laboratory Unit at Babcock University Teaching Hospital in Ilishan-Remo,Ogun State.Phytochemical screening and antibacterial testing were conducted using standard biochemical techniques and the Punch-hole agar diffusion method,respectively.Results:Qualitative phytochemical screening of the plant extracts revealed the presence of flavonoids,glycosides,and saponin in both plants,excluding terpenoids.Alkaloids were identified only in Vernonia amygdalina.Despite these phytochemicals,neither plant displayed inhibitory effects on the tested bacterial isolates(Escherichia coli,Proteus mirabilis,Klebsiella pneumoniae,and Salmonella typhi)when tested individually or in combination.Intriguingly,combining the fresh and dried leaf extracts of Momordica charantia and Vernonia amygdalina with a standard drug resulted in smaller mean zone diameters of inhibition(Escherichia coli range:14 mm–16 mm,Proteus mirabilis range:31 mm–35 mm,Klebsiella pneumoniae range:13 mm–22 mm,and Salmonella typhi range:35 mm–38 mm)compared to the drug tested alone(16 mm–45 mm).Conclusion:Despite previous indications of antibacterial properties in various extracts of V.amygdalina and M.charantia leaves,our study presents contradictory results,prompting the need for further investigation despite the presence of significant phytochemicals.

Effect of Preservation on Two Different Varieties of <i>Vernonia amygdalina</i>Del. (Bitter) Leaves

Vernonia amygdalina Del. is one of the leafy vegetables that can be used in an attempt to alleviate the problem of micronutrient malnutrition, prominent in tropical Africa. In order to ensure availability in non-growing areas or seasons, the vegetable needs to be preserved. Processing and preservation methods influence the nutrient content of vegetables. The present study was aimed at determining the effects of preservation on two different varieties of V. amygdalina (bitter) leaves (broad and small leaves). To this effect, evaluations were made on the chlorophyll content, phytochemicals, and antioxidant capacity of the two varieties of bitter leaf (V. amygdalina Del.) stored at 4℃ and –20℃ over a period of two weeks. Results showed a significant decrease in all parameters studied for both varieties at –20℃ except for the free radical reducing power (FRAP), DPPH radical scavenging activity (%RSA) and nitric oxide radical scavenging activity (%RSA) of V. amygdalina broad leaves where increase in scavenging activity was observed. Thus, it was concluded that to preserve the chlorophyll, phenol, total soluble proteins and reducing sugar levels, preservation at 4℃ is recommended. The present study finding would be useful during short-term preservation of bitter leaves for soup preparation and/or its aqueous extract for ethnomedicinal purposes, especially the small leaf variety.

Evaluation of the anti-inflammatory activity of extract of Vernonia Amygdalina

Objective:To investigate the anti-inflammatory activity of the extract of Vernonia amygdalina (V.A).Methods:Inflammatory response was induced by topical application of croton oil dissolved in suitable vehicle on the rat ear.After 6 hrs,cutting out the ear quantitated the response.The cut ear was weighed and the increase in weight relative to control group was evaluated.Results:When co-applied with croton oil to the rat ear extract of V.A.produced a reduction in the inflammatory response when croton oil alone was applied to the rat ear.The extract produced(69.1 +2.0)%reduction of the inflammatory response produced by croton oil alone,lower than the reduction of the inflammatory response produced by acetyl salicylic acid[(71.1±2.0)%].Conclusions:This finding suggests that extract of V.A.exhibits antiinflammatory activity and may explain the usefulness of the leaves of this plant in the treatment of inflammatory disease conditions by traditional healers.

Immunological effect of aqueous extract of Vernonia amygdalina and a known immune booster called immunace and their admixtures on HIV/AIDS clients:a comparative study

Objective:To investigate the immunological effect of Vernonia amygdalina(V.amygdalina) leaf extract and immunace on HIV infected patients taking highly active antiretrwiral therapy. Methods:Fresh V.amygdalina leaves were collected within Nsukka area in Enugu State.The leaves were rinsed with distilled water.Two handful of cleaned fresh leaves were soaked in 200 mL water and squeezed gently by hand to a mixture.Clients were divided into four groups and each group was given different combination.They took the medication for four weeks.The immune effect was tested against marketed immune booster in some retroviral clients.Results:The mean absolute CD4 count was increased in the client who took the extract or supplement.And the clients who took both the extract and supplement had a greater increase in the CD4 count.The increased CD4 was significant as compared with the control group(P<0.05).The skin rashes were also improved in the entire groups.Conclusions:It can be concluded that the aqueous extract of V.amygdalina and immunace or both have immunological effect on HIV infected patients. Therefore,we suggest that the V.amygdalina extract or immunace or both could be used as adjuvant in the management of HIV/AIDS clients.

<i>Vernonia amygdalina</i>—Induced Growth Arrest and Apoptosis of Breast Cancer (MCF-7) Cells

Breast cancer is the second leading cause of cancer-related deaths of women in the United States. Fortunately, the mortality rate from breast cancer has decreased in recent years due to an increased emphasis on early detection and more effective treatments. Although great advancements have been made in the treatment and control of cancer progression, significant deficiencies and room for improvement remain. The central objective of this research was to further determine the in vitro mechanisms of Vernonia amygdalina (VA) leaf extracts as an anticancer candidate for the treatment of breast cancer. To achieve our objective, MCF-7 cells were treated with different concentrations of VA for 24 hand 48 h. Cell viability, live and dead cells were determined by the means of trypan blue exclusion test. Live and dead cells were further evaluated by propidium iodine (PI) assay using the Cellometer Vision. Cell apoptosis was measured by flow cytometry assessment using annexin V/PI kit. Data obtained from the trypan blue test demonstrated that VA treatment reduces cell viability in a concentration- and time-dependent manner. Result of the PI assay showed a gradual increase in the population of necrotic cells (fluorescence positive cells) in VA-treated cells compared to the control cells (fluorescence negative cells). Treatment of these cancer cells (MCF-7) for 48 h at concentrations ranging from 250 μg/mL to 1000 μg/mL caused early signs of apoptosis resulting from phosphatidylserine externalization as judged by annexin V assay. We observed a strong concentration-response relationship with regard to VA exposure and annexin V/PI positive cells. In summary, our finding demonstrates that VA-induced cytotoxicity and apoptosis in MCF-7 cells involve phosphatidylserine externalization accompanied by secondary necrotic cell death. With previous findings in our laboratory, the data generated in the present study confirms that VA is a valuable botanical therapeutic agent for the treatment of breast cancer.

Antidiabetic fallacy of Vernonia amygdalina(bitter leaves) in human diabetes

Objective:Aim of present study is to scientifically,verify the antidiabetic activity/potency of Vernonia amygdalina in human diabetes.Methods:A search was made at Nnewi,South - East Nigeria for known diabetes who use Vernonia amygdalina either as their sole or supplementary antidiabetic.A total of ten volunteers comprising, eight females and two males were recruited.They were all of age range of 36-50 and average weight of 78 kg and suffering from non - insulin form of diabetes.The purpose of the study was explained to them and their consent obtained.They were asked not to take any other antidiabetic outside Vernonia amygdalina throughout the four weeks study period.There was however,no form of restrictions to their choice of diet or life style. They were requested to abstain from any drugs a week prior to commencement of study.Their prescriber’s dosage range was followed and minimum daily dose of 210 mL(approximately 220 mg of dry extract) was administered in Week-1,followed by daily dose of 420 mL(440 mg) in Week-2.In Week-3 they received 630 mL (660 mg) daily dose and in Week-4,they received daily dose of 840 mL(880 mg).Their fasting blood sugar were estimated pre-crude drug administration and on weekly basis for the four week study period.Their weekly weights were measured to check for possible weight gain or loss.Results were subjected to statistical analysis and Students T-Test was used to calculate P-value.P-value≤0.05 were considered significant.Results:It was observed that all the volunteers in the study group were taking Vernonia amygdalina only as supplementary. Two volunteers dropped out of the study at the end of Week-3 leaving us with 8 in Week-4.There was no significant bodyweight change within the four week study.The starting mean fasting blood sugar which was 133.3 mg/dL(7.41 mmol/L) rose to 136.6 mg/dL(7.59 mmol/L) in Week-1,to 149.5 mg/dL(8.31 mmol/L) in Week-2 and to 166.5 mg/dL(9.30 mmol/L) in Week-3.Week-4 had us left with 8 volunteers with a mean of 190.6 mg/dL(10.59 mmol/L).There was significant differences in increase in sugar levels between the pre-crade extract administration and treatment period with Vernonia amygdalina(P≤0.05 for Week-1,Ps?0.02 for Week-2,P^0.01 for Week-3 and PssO.001 for Week-4).Conclusion:Claims of antidiabetic efficacy of Vernonia amygdalina in human diabetes are scientifically non verifiable based on our work hence these claims are false.We also feel bold to state that we could not demonstrate any antidiabetic activity of Vernonia amygdalina in human subjects.We recommend that NAFDAC and all relevant agencies must sit up and control all forms advertorial on Medicinal plants until such are well studied and proven.

Antiarthritic activity of Vernonia amygdalina in albino rats

Objective:To evaluate the antiarthritic activity of water extract of leaves of Vernonia amygdalina(V.A.) on arthritis induced model of rats.Methods:Arthritis was induced in male albino Wister rats by injection of croton oil(0.1 mL) into the left foot pad of the animals.Treatment with V.A.at 200 and 400 mg/kg and standard Indomethacin(0.3 mg/kg) was started on the same day and continued up to the 12th day.The paw volume was measured on the 1st,5th,12th and 21st day,respectively for both the paws and anti-arthritic activity was evaluated.Results:The extract of V.A.produced reduction in the inflammation of the paw due to croton oil.The antiarthritic action started on the 5th day and continued till the 12th day and the activity was comparable to that of the standard on both days.V.A.significantly inhibited adjuvant induced arthritis and had significant ant-inflammatory effect(P【0.05).Conclusion:This report therefore clearly showed that V.A.significantly inhibited adjuvant induced arthritis in rats as it significantly reduced the paw volume on the 12th day and may explain the effectiveness of this plant when used in the tropics for the treatment of arthritis.

Adsorption and Thermodynamics Study of the Inhibition of Corrosion of Mild Steel In H₂SO₄Medium Using <i>Vernonia Amygdalina</i>

In this work, adsorption and thermodynamics study of the inhibition of corrosion of mild steel in H2SO4 medium using Vernonia amygdalina was carried out. The inhibitive and adsorptive properties of ethanol extract of Vernonia amygdalina for the corrosion of mild steel in 0.2 M H2SO4 solutions was investigated using weight loss technique. The result has proved that that the extract is a good inhibitor of corrosion of mild steel in H2SO4. The inhibition efficiencies ranged from 23.37 to 38.59% and from 22.45 to 35.78% at 303 and 323K respectively. The inhibition efficiency of the extract decreased as temperature and time of immersion increased but increased with increase in concentration of extract. The adsorption of the inhibitor on surface of mild steel was found to be exothermic, spontaneous and consistent with the mechanism of physical adsorption as the value for heat of adsorption ranged from -2.12 to -4.87KJ mol–1. The adsorption data fitted well to Langmuir, Temkin, Frumkin and Flory-Huggins adsorption isotherms.

扁桃斑鸠菊叶促进灵芝胞外多糖高产条件优化及抗氧化活性研究

胞外多糖(EPS)是灵芝液体发酵的主要活性产物,为提高灵芝胞外多糖含量,在发酵培养基中添加扁桃斑鸠菊叶粉末,采用单因素和正交试验优化发酵条件,红外光谱表征灵芝多糖结构,并分析其抗氧化活性。单因素实验结果表明,扁桃斑鸠菊叶粉末优化的添加量为4 g/L,胞外多糖含量与对照相比提高到167%;正交试验优化的发酵条件为:发酵时间12 d、起始pH5.0、转速120 r/min、扁桃斑鸠菊叶粉末的添加量为4 g/L,在此条件下,胞外多糖含量达到13.05 g/L;红外光谱图表明添加和未添加扁桃斑鸠菊叶粉末的灵芝胞外多糖类型相似;抗氧化活性实验显示扁桃斑鸠菊叶粉末添加对胞外多糖清除ABTS+·的影响较小,但增强了其对·OH、DPPH·清除能力和Fe3+还原能力。扁桃斑鸠菊叶能有效提高灵芝胞外多糖的含量,为灵芝多糖的高效生产提供新思路。

响应面法优化南非叶黄酮提取及抗氧化活性分析

以南非叶为主要材料,研究南非叶总黄酮的提取工艺及体外抗氧化活性。在乙醇浓度、料液比、提取时间三个单因素试验的基础上,采用响应面法优化其总黄酮提取的工艺,并测定南非叶黄酮的抗氧化能力。结果表明,响应面法优化的南非叶黄酮提取工艺为:乙醇浓度为77%,料液比为1∶38(g/mL),提取时间为30 min,在此条件下得到南非叶总黄酮提取率为1.84%。在一定质量浓度范围内,南非叶黄酮提取液的总还原能力随着浓度的升高而增强,在黄酮质量浓度为0.05~0.25 mg/mL范围内,随着样品浓度的增加,对DPPH自由基清除率逐渐增加,当黄酮浓度为0.2 mg/mL时清除率达到93.50%,这表明南非叶黄酮具有较强的抗氧化活性。

Therapeutic Benefits of Vernonia amygdalina in the Treatment of Inflammation and Its Associated Diseases

Background:In the presence of a stimulus that disrupts homeostasis,the body elicits a response known as in-flammation.The inflammatory response is expected to restore the normal functioning of the body and initiate healing where necessary.However,the persistent activity of acute inflammation results in chronic inflammation which causes adverse consequences associated with diseases such as diabetes and arthritis.In traditional medical practice,Vernonia amygdalina is used to treat several ailments such as malaria,fever,diabetes,and inflammatory conditions such as those related to pain and swelling.Objective:This review seeks to explore and discuss the therapeutic benefits of V.amygdalina in the treatment of inflammation and its associated diseases.Methods:We reviewed the scientific literature indexed in PubMed,ScienceDirect and Springer,and discussed the reported anti-inflammatory properties of V.amygdalina and its curative activity in inflammation-associated diseases.Results:A total of 30 published articles were identified describing the therapeutic effect of V.amygdalina in predominately experimental models.The anti-inflammatory properties of V.amygdalina have been linked to the presence of bioactive phytoconstituents predominantly present in the leaves of the plant.Conclusions:Multiple studies have demonstrated that the aqueous and ethanolic extracts of V.amygdalina can inhibit the production of proinflammatory cytokines and enzymes in inflammatory cells,reducing inflammation and its associated complications.We critically appraise the current evidence,and discuss the potential use of this medicinal plant in the treatment of inflammatory conditions.

南非叶保健饮料的研制

南非叶含有黄酮类等有效活性成分,该类物质具有降血压,降胆固醇提高免疫力的保健作用.试验通过单因素和正交试验法优化调配南非叶保健饮料的配方,并对南非叶饮料的理化指标进行测定.得出南非叶饮料的最佳配方为:南非叶提取液15%、白砂糖9%、蜂蜜1%、柠檬酸0.03%,在此条件下测得南非叶饮料的可溶性固形物含量为9.0%,黄酮含量为3.54mg/100mL,pH为3.8,微生物含量为35CFU/mL.

Hypoglycemic efficacy of Ocimum gratissimum and Vernonia amygdalina compared with insulin and glibenclamide in type Ⅰ and type Ⅱ diabetic rat models

Objective: To compare the efficacy of Ocimum gratissimum (O. gratissimum) and Vernonia amygdalina (V. amygdalina) with those of insulin and glibenclamide.Methods: Type Ⅰ and Ⅱ diabetes mellitus (DM) were induced by a single intraperitoneal injection of 65 mg/kg of streptozotocin and intraperitoneal administration of nicotinamide (100 mg/kg) along with streptozotocin, respectively. The state of diabetes was confirmed weekly by testing blood glucose level using a glucometer.Results: The weekly blood glucose levels were higher in type I DM than in type Ⅱ DM. Type Ⅰ DM plus O. gratissimum showed a weekly progressive significant reduction in blood glucose compared to type Ⅰ DM control. Type Ⅰ DM control showed a duration dependent significant higher blood glucose concentration compared to normal control. Type I DM plus V. amygdalina also showed a time dependent significant lower glucose level compared to normal control and type Ⅰ DM control. Combination treatment of type Ⅰ DM (O. gratissimum plus V. amygdalina) showed a significantly elevated glucose concentration compared to normal control which was similar to type I DM control. Insulin treatment in type I DM showed a weekly progressive significant reduction of glucose concentration compared to normal control and type I DM control. Type Ⅱ DM control showed a fairly constant blood glucose concentration throughout the duration of treatment that was significantly higher than that of the normal control. Type Ⅱ DM plus O. gratissimum showed a fairly steady significant reduction of glucose concentration compared to type Ⅱ DM control and normal control. Type Ⅱ DM plus V. amygdalina also showed a fairly constant significant reduction of glucose concentration compared to type Ⅱ DM control and normal control. Type II DM (O. gratissimum plus V. amygdalina) showed a slightly progressive significant reduction of glucose concentration compared to normal control and type Ⅱ DM control. Type Ⅱ DM with glibenclamide showed almost steady significant reduction in glucose concentration compared to normal control and type Ⅱ DM control. Conclusions: From the result, it is evident that O. gratissimum and V. amygdalina administration produces more potent hypoglycemic activity than insulin and glibenclamide in type I and Ⅱ DM models, respectively.

扁桃斑鸠菊挥发性成分和无机元素分布

目的研究扁桃斑鸠菊挥发性成分和无机元素的分布。方法采用固相微萃取-气相色谱-质谱联用技术和电感耦合等技术,对中国产扁桃斑鸠菊不同部位挥发性成分、无机元素进行分析测定。结果从其根、茎、叶中分别鉴定出44、67、57个化合物,分别占挥发性成分的83.9%、92.0%、88.6%;共检测出19种无机元素,其中As、Be、Bi、Co元素含有量低,没检测出;根、茎、叶中含有量最高的3种无机元素分别为Mg、Al、Fe。结论扁桃斑鸠菊含有丰富的挥发性成分和无机元素,而且在不同部位的分布存在差异。

南非叶化学成分及药理作用研究进展

南非叶即扁桃斑鸠菊(Vernonia amygdalina Del.)的叶,原产于热带非洲,具有明确的抗肿瘤效果,在东南亚、台湾等地民间使用较多,近年来才移植到中国大陆。对南非叶品种基源、化学成分、抗肿瘤药理作用及临床应用几个方面进行综述,为开发抗癌药物提供新的思路。另外从中医药的角度对南非叶进行研究,可为扩展中药资源和发展中医药提供基础与依据。

超声波辅助法提取南非叶多酚的工艺研究

以乙醇为提取溶剂,选用超声波辅助法提取南非叶中的多酚.以多酚提取率为评价指标,对液料比、乙醇体积分数、超声时间和超声温度进行单因素实验,并通过响应面分析,创建多元二次回归模型,确定了最佳的工艺条件.结果表明超声温度是影响南非叶多酚提取率的最显著因素,乙醇体积分数和超声温度间的交互作用对提取率影响差异最显著.南非叶多酚的最佳提取条件为:液料比为30 mL/g,乙醇体积分数为65%,超声时间31 min和超声温度为59℃,在此条件下获得提取率实际值为20.33 mg/g,相比理论预测值20.36 mg/g,算得相对误差仅0.15%,表明此模型具有较好可靠性与准确性,为南非叶多酚的提取及开发提供了新的研究方向.

药用植物—扁桃斑鸠菊的微枝繁殖技术研究

为进一步探讨扁桃斑鸠菊种苗的扦插繁殖技术,开展了扁桃斑鸠菊3种不同长度带顶芽插穗和4种不同浓度植物生长调节剂IBA处理对扁桃斑鸠菊扦插繁育的影响研究。结果表明:不同长度带顶芽扁桃斑鸠菊插穗对扁桃斑鸠菊扦插效果影响不明显,但对其繁殖系数的影响差异较大,采用5 cm长的插穗进行扁桃斑鸠菊微枝繁殖,其繁殖系数是采用15 cm长插穗的3倍多;采用不同浓度植物生长调节剂IBA对扁桃斑鸠菊插穗基质进行处理,扁桃斑鸠菊扦插效果影响差异明显,采用浓度为5 mg·L-1植物生长调节剂IBA对扦插基质处理,可明显缩短生根时间,插穗的生根数、平均根长和生根率等都显著高于其它浓度组。采用从2年生母株上采集的5 cm长、半木质化、带顶芽的嫩枝作插穗,插于黄心土基质中,用浓度5 mg·L-1的植物生长调节剂IBA浇透基质,并于扦插完成后,立即用浓度5 mg·L-1的的IBA溶液对基质喷淋一次,生根率可达98.01%。

响应面法优化扁桃斑鸠菊黄酮提取及抗氧化活性研究

为探讨提取扁桃斑鸠菊(Vernonia amygdalina Del.)黄酮及自由基的最佳提取工艺,以扁桃斑鸠菊的叶片为试材,运用单因素和响应面试验相结合的方法,通过超声波辅助对其总黄酮的提取进行优化,并对其黄酮含量进行测定与抗氧化活性分析。研究结果表明:扁桃斑鸠菊黄酮最佳提取条件为超声波功率409.6 W,超声频率35 kHz,乙醇浓度100%,料液比为1∶48.5 g/mL,提取温度61.9℃,提取时间20 min,黄酮得率为5.7%。当扁桃斑鸠菊黄酮浓度为2 mg/mL时,其对·OH、DPPH·和O_2^-·的最大清除率分别为54.7%、79.2%和32%,并具有很好的还原能力。通过热溶剂浸提超声波辅助提取法提取扁桃斑鸠菊中的黄酮类化合物,所用时间短,要求温度低,提取率好,方法简单易行,具有明显的优势。

扁桃斑鸠菊叶酵素发酵过程中理化性质分析、抗氧化能力评价及对氧化应激细胞防护作用研究

以扁桃斑鸠菊叶为原料制备酵素,监测发酵过程中理化指标的变化,通过ABTS+自由基、羟基自由基清除能力考察其发酵过程中抗氧化能力变化,并利用人正常肝细胞(WRL-68)模型考察其对氧化应激的保护作用。结果表明:对比酵素第2和第55 d,pH从4.24±0.01降至3.46±0.07,可溶性蛋白质、总糖、总酚、总黄酮含量呈下降趋势,分别从0.95±0.02、244.94±4.89、6.05±0.03、0.37±0.01 mg/mL降至0.71±0.02、34.26±0.57、3.42±0.21、0.08±0.01 mg/mL。总酸含量呈上升趋势,从0.15±0.01提高至0.95±0.01 mg/mL。在第2~28 d,抗坏血酸含量从25.36±0.52提高至28.44±0.01μg/mL,随后呈下降趋势;ABTS+自由基清除能力在第18 d最强,为73.72%±0.86%,第28 d羟基自由基清除能力最高,为54.14%±0.43%,且ABTS+自由基、羟基自由基清除能力和总酸含量呈显著正相关性(P<0.01);WRL-68细胞经H_(2)O_(2)处理造模后,酵素处理组的胞内ROS显著降低(P<0.05),胞内抗氧化系酶SOD、CAT、GSH-Px活提高。综上,扁桃斑鸠菊叶酵素在发酵中期具有较强的清除自由基能力,且经酵素预处理后WRL-68细胞抵御氧化应激的能力提高。