Clonal propagation of guava (Psidium guajava Linn.) by stem cutting from mature stockplants

The study describes the scope of clonal propagation of guava (Psidium guajava Linn.) by stem cutting collected from mature stockplants. Cuttings were treated with 0, 0.2%, 0.4% and 0.8% IBA solution and rooted in the non-mist propagator. Rooted cuttings were allowed to grow in the polybags filled with soil and cow-dung mixed in the ratio of 3: 1 (by volume) for three months to assess the steckling capacity and initial growth performance. The study reveals that the species is amenable for clonal propagation by mature stem cutting. The highest rooting percentage (60%) was observed in the cuttings treated with 0.4% IBA solution followed by 0.2% IBA and the lowest was in controlled cuttings. The maximum number of primary root (32.7) was developed in the cuttings treated with 0.8% IBA solution followed by 0.4% IBA and the lowest was in the cuttings without IBA treatment. The highest survival percentage (70.9) was observed in the cuttings rooted with 0.4% IBA treatment and the lowest (58.3) was in the cuttings without any treatment. However, there was no significant variation in height growth of cutlings due to IBA treatments in rooting.

Hepatoprotective Effect of Guava (<i>Psidium guajava</i>L.) Leaf Extracts on Ethanol-Induced Injury on Clone 9 Rat Liver Cells

Guava (Psidium guajava L.), a tropical fruit, belongs to Myrtaceae family. Leaves and fruits of guava have been reported to have an anti-diarrheal, hypoglycemic, lipid lowering, anti-bacterial in addition to antioxidant activities. The aim of this study was to investigate several guava leaf extract cytotoxic effects on healthy clone 9 liver cells and its hepatoprotective effects on ethanol-induced heap-toxicity. It was discovered that when the clone 9 liver cells were treated with guava (Psidium guajava Linn.) extracts for 24 hours, there was no retardation of growth as well as when ethanol and acetone extracts at low concentrations 100 μg/mL and 50 μg/mL were administered however cytototoxic effects were detected at higher concentrations. Water and hot water extracts in concentrations lower than or equal to 500 μg/mL revealed no cytotoxic effects. Injury induction to healthy clone 9 liver cells using 5% alcohol concentration for 30 minutes revealed the hepatoprotective properties of guava (Psidium guajava Linn.) extracts. This was significant in concentrations of 100 μg/mL or lower for ethanol and all concentrations for hot water extracts. Hot water extracts showed higher hepatoprotective and lower cytotoxic properties than other extracts.

Antibacterial Activities of <i>Psidium guajava</i>(Guava) and <i>Velvet tamarin</i>(Icheku) Local Chewing Sticks on <i>Streptococcus mutans</i>Isolated from Human Mouth

Globally dental diseases are mainly caused by Streptococcus mutans, it is one of the leading causative agents of dental caries worldwide, because of its resistance to conventional antibacterial agents, alternative therapies are used to control resistance of oral pathogens. This research was done to determine the antibacterial activities of Psidium guajava (guava) and Velvet tamarin (Icheku) chewing sticks on Streptococcus mutans isolated from the oral cavity. The study was conducted in Owerri Imo State Nigeria during November-December period. Phytochemical analysis of the plant extracts was done using appropriate techniques. The procedure used for antimicrobial susceptibility test was disk diffusion method. Serial dilutions of Psidium guajava (guava) and Velvet tamarind (Icheku) extracts were prepared, Muller-Hinton media was used to put together the extract of serial dilutions of Psidium guajava (guava) and Velvet tamarin (Icheku) and a microbiological procedure were used for visually determining the minimum inhibitory concentration as well as minimum bactericidal concentration. Phytochemical evaluation of the plants’ extracts revealed that it contains saponins, tannins, alkaloid, steriods, glycosides and phenol. The results obtained from the antibacterial susceptibility testing of the extracts against Streptococcus mutans showed that the zones of inhibition recorded ranged from 18 mm to 27 mm. Ethanol (Soxhlet) extract of Icheku twig showed no zone of inhibition on the isolated organism. The ethanol (soxhlet) extract of the individual Psidium guajava (guava) and Velvet tamarin (Icheku) has a better antibacterial effect when compared to their aqueous extracts and combined forms. Psidium guajava (Guava) and Velvet tamarin (Icheku) twigs are made up of composite that is active against S. mutans and can be used in oral hygiene. There is a need for further investigation on the plant extracts as the rural poor make use of it because it is cheap, readily available and the rich also use it once they are in the village mostly in Eastern Nigeria. Similarly chewing sticks has been reported to be practiced by 90 of rural population in Nigeria.

Determination of 2 Flavonoids in Psidium guajava Linn. from Different Habitats in Guizhou

[ Objective] This study was conducted to determinate the contents of hyperoside and isoquercitrin in the leaves of Psidium guajava Linn. from different areas of Guizhou Province, which would provide data support for production and quality control of P. guajava leaf material. [ Method] The contents of hypereside and isoquercitrin were measured by HPLC under following conditions： Agilent XDB-C18,4.6 mm x 250 ram, 5 ttm, CH3CN-0.1% HCOOH （13： 87） as mobile phase, column temporature at 25 ℃, detection wavelength of 257 mn and flow rate at 1.0 ml/min. [ Result ] The results showed that leaves of P. guajava from dif- ferent producing areas contained variable hypereaide and isoquercitrin contents in the same period, and the differences in quality were obvious between different are- as. [ Conclusion] The method for detecting the contents of hypereside and isoquercitrin in P. guajava leaf materials is simple with reliable accurate results. The P. guajava leaf material produced in Gouting Township, Luedian County has better quality.

番石榴(Psidium guajava L.)资源的ISSR分析初报

用ISSR技术分析16份番石榴资源的亲缘关系。结果表明:从11条能扩增出较清晰多态性指纹图谱的引物中,筛选出了6条引物能对所有资源均扩增出可重复的清晰指纹,共扩增出44条可重复带,其中多态性带占61.4%;扩增结果可将16份供试资源一一分开,部分资源存在同名异物现象;各资源间的相似系数在0.689～0.981之间,平均为0.841。UPGMA聚类结果将16份资源分成了3组。

A review of meroterpenoids and of their bioactivity from guava(Psidium guajava L.)

Psidium guajava Linn.(family Myrtaceae),is commonly known as guava.Guava is consumed in large quantities throughout the world due to its ease of cultivation and high nutritional value.As an important perennial fruit tree distributed around the world,guava has been widely used to manage various diseases in traditional medicine.Guava has been shown significant bioactivity such as antioxidant,anti-inflammatory,immunomodulatory,antimicrobial,antidiabetic,and anticancer properties.A large number of studies indicated that guava contains various type of phytochemicals including monoterpenes,sesquiterpenes,triterpenes,phenolics,and meroterpenoids.Among them,meroterpenoids are characteristic components of guava,which are hybrid of acylphloroglucinol with terpenoids(monoterpenes,sesquiterpenes).Modern pharmacological investigations showed intricate Psidium meroterpenoids possess a wide range of bioactivities.Although a large and growing body of literatures have investigated the Psidium meroterpenoids isolated from guava,a comprehensive review of Psidium meroterpenoids and their bioactivities has not been conducted.Therefore,this review provides a comprehensive compile of 75 meroterpenoids isolated from guava and their bioactivities between 2007 and May 2022.Furthermore,the possible biosynthesis way and future directions of Psidium meroterpenoids have also been discussed.

套袋对新世纪番石榴果皮色素及酚类物质的影响

研究了番石榴(PsidiumguajavaL.)新世纪品种果皮叶绿素、类胡萝卜素、类黄酮和花青苷等色素及总酚的变化动态以及套袋的影响。结果发现,花青苷在果实色泽发育中的作用很小;叶绿素、类胡萝卜素的降解与果实成熟同时发生,二者的综合表现决定果实的色泽;套袋明显抑制了果皮叶绿素、类胡萝卜素和类黄酮的合成,提高了果皮总酚含量。建议果实在采收及贮运过程中不要除袋,以进一步提高其商品性。

番石榴叶水提取物对糖尿病小鼠小肠α-葡萄糖苷酶活性的影响

目的研究番石榴叶水提取物对α-葡萄糖苷酶的抑制作用。方法蒸馏水浸提、浓缩、干燥制备番石榴叶水提取物。昆明小鼠链脲佐菌素腹腔注射诱导糖尿病模型,以小鼠小肠粘膜生理盐水匀浆液作为α-葡萄糖苷酶,与双糖底物孵育,比色法测定葡萄糖产量代表α-葡萄糖苷酶的活性。比较正常小鼠和糖尿病小鼠小肠粘膜α-葡萄糖苷酶活性,以及番石榴叶水提取物对小肠粘膜α-葡萄糖苷酶活性的影响,Lineweaver-Burk作图判断水提物对α-葡萄糖苷酶抑制作用类型。结果番石榴叶水提取物对小肠α-葡萄糖苷酶活性具有较强的抑制作用,并呈剂量效应关系;对蔗糖酶和麦芽糖酶的半数抑制浓度(IC50)分别为1.0g/L和3.0g/L,抑制作用类型为竞争性和非竞争性混合型。结论番石榴叶水提取物具有抑制糖尿病小鼠小肠粘膜α-葡萄糖苷酶作用。

番石榴发育期生物活性物质研究

番石榴风味独特,营养丰富。本研究以‘珍珠’番石榴和‘水晶’番石榴为试材,研究番石榴果皮和果肉中生物活性物质含量及其与抗氧化能力关系。结果表明:番石榴果皮和果肉中,‘珍珠’番石榴的总酚、类黄酮、酚酸、单宁含量均高于‘水晶’番石榴;番石榴的果皮和果肉发育过程中总酚、类黄酮、酚酸、叶绿素及类胡萝卜素含量均呈下降趋势;番石榴果皮中生物活性物质含量高于果肉,且果皮抗氧化能力高于果肉;在生物活性物质与总抗氧化能力的相关性方面,总酚含量相关性最高。本研究结果可为番石榴加工产品开发提供理论和实践基础。

番石榴成花习性的调查

调查了番石榴 (PsidiumguajavaL .)‘新世纪’、‘无核’和‘水晶’品种的成花特点 ,结果发现 ,着生花蕾的第 2～ 4节叶片处枝梢的直径明显大于其他叶位处枝梢的直径 。

番石榴果实采后处理与保鲜技术研究进展

就番石榴果实采后不耐贮运,制约中国番石榴产业的发展等问题。对国内外番石榴果实采收以及采后热处理、涂膜、1-甲基环丙烯(1-MCP)、CaCl2、杀菌剂、辐照、臭氧等果实采后处理技术及包装、贮藏保鲜技术的研究进展情况作了综述并进行展望。

番石榴叶提取物对小鼠肝脏抗氧化作用研究

目的研究番石榴叶提取物抗氧化活性。方法干燥的番石榴叶分别用蒸馏水、65%和95%乙醇浸提,浸提液过滤、浓缩、干燥得到3种提取物。测定各提取物对羟自由基清除率和脂质过氧化抑制率。紫外分光光度法分析提取物中总黄酮含量,高效液相色谱(HPLC)和紫外可见吸收光谱法(UV)对黄酮类化合物初步鉴定。结果水、65%和95%乙醇提取物均具有清除羟自由基和抑制脂质过氧化作用,且呈剂量-效应关系,对羟自由基清除作用的半数有效浓度(EC50)分别为0.63、0.47和0.58g/L,对脂质过氧化抑制作用的半数有效浓度(EC50)分别为0.20、0.035和0.18g/L,总黄酮含量分别为3.28、30.71和55.98g/kg。结论番石榴叶水和乙醇提取物具有较强的抗氧化作用,其中黄酮类化合物可能是其功效成分之一。

番石榴叶乙酸乙酯萃取物化学成分研究

目的:寻找番石榴叶乙酸乙酯萃取物中具有降糖活性的功能成分。方法:采用硅胶、羟丙基葡聚糖凝胶柱层析与溶剂重结晶法进行单体分离纯化;通过分析化合物的理化性质、核磁共振谱(nuclear magnetic resonance spectrum,NMR)、质谱(mass spectrum,MS)数据进行结构鉴定;建立降糖脂肪细胞模型评价主要单体的降糖活性。结果:从番石榴叶乙酸乙酯萃取物中共分得14个单体化合物,分别鉴定为:金丝桃苷(化合物1)、异槲皮苷(化合物2)、槲皮素-3-O-β-D-木糖苷(化合物3)、广寄生苷(化合物4)、番石榴苷(化合物5),槲皮素-3-O-(2’’-O-没食子酰基)-α-L-阿拉伯吡喃糖苷(化合物6),槲皮素(化合物7)、没食子酸乙酯(化合物8)、齐墩果酸(化合物9)、β-谷甾醇(化合物10)、isocaryolan-9-one(化合物11)、(-)-epiglobulol(化合物12)、t-cadinol(化合物13)和muurola-4,10(14)-dien-1-ol(化合物14)。降糖脂肪细胞模型测定结果表明,5种主要黄酮苷均具有降糖活性,其中以番石榴苷和广寄生苷降糖效果最好,40μmol/L浓度下促葡萄糖摄取值分别达到了(1.74±0.076)、(1.81±0.029)mmol/L。结论:化合物6、8、11~14为首次从该植物中分得,化合物11为一新的天然产物;番石榴苷和广寄生苷可能为番石榴叶主要降糖活性成分。

番石榴果实采后生理和采后病害研究进展

番石榴果实采后易腐烂劣变,不耐贮运,制约着中国番石榴产业的进一步发展。本文就国内外关于番石榴果实采后生理和采后病害的研究进展进行综述,指出了番石榴果实采后研究存在的问题和今后需要进一步研究的领域。

番石榴多酚氧化酶的部分纯化及其特性研究

番石榴PPO的粗提取液经过80％硫酸铵盐析和DEAE—Toyopearl 650M、CM-Sephadex C-50离子交换柱层析分离后，被纯化了约126倍，回收率为16．13％。该酶迅速地催化焦性没食子酸的酶促氧化反应，而对对苯二酚和绿原酸则完全无催化活性。该酶对焦性没食子酸的Krn值为4．6mmol/L，其最适pH为7．5，pH稳定性范围在pH4．0--11．0，最适温度为50℃，热稳定性相对较高，在≥90℃加热10min后仍残留约15％的酶活性。该酶的最佳抑制剂是抗坏血酸和NaHSO3，其次是植酸、盐酸-L-半胱氨酸、柠檬酸，Ca^2＋、Mg^2＋等金属离子对该PPO也有较强的抑制作用。

番石榴叶乙酸乙酯萃取物化学成分研究(Ⅱ)

目的：研究番石榴叶乙酸乙酯萃取物化学成分。方法：采用硅胶、Sephadex LH-20色谱与重结晶方法进行分离纯化,采用波谱法进行结构鉴定。结果：从番石榴叶乙酯乙酯萃取物中共分得了11个化合物,分别鉴定为：6,10,14-三甲基-2-十五烷酮（1）、植物醇乙酸酯（2）、cubenol（3）、桉树素（4）、正二十二酸对羟基苯乙醇酯（5）、8-甲基-5,7-二羟基二氢黄酮（6）、6-甲基-5,7-二羟基二氢黄酮（7）、白桦脂酸（8）、鼠尾草酚（9）、槲皮素（10）、2,4,6-三羟基-3,5-二甲基二苯甲酮-4-O-β-D-（6-O-没食子酰基）-葡萄糖苷（11）。结论：其中,化合物1～9均为首次从该植物中分离得到。

改良CTAB法提取番石榴叶片总DNA

目的:从番石榴叶片中快速提取高质量的总DNA。方法:改良CTAB法。主要改进之处在于不用液氮,而是直接研磨硅胶干燥样品;用高浓度CTAB、低浓度乙醇与NaCl盐析相结合等方法去除多糖。结果:应用改良后的方法可以快速提取番石榴叶片总DNA,有效去除组织中的多糖、蛋白质,抑制提取过程中的组织褐变。提取的DNA可用于限制性内切酶酶切和PCR扩增。结论:传统CTAB法经过改良,可用于快速提取番石榴高质量DNA。

一测多评法测定番石榴叶中6种黄酮类成分的含量

为建立同时测定番石榴叶中6种黄酮类成分(金丝桃苷、异槲皮苷、瑞诺苷、番石榴苷、萹蓄苷、槲皮素)的一测多评法。本研究以金丝桃苷为内参物,采用HPLC法,确定金丝桃苷与另外5种成分的相对校正因子,并通过获得的校正因子计算后5种成分的量;同时采用外标法测定11批番石榴叶的含量。结果表明11批番石榴叶的QAMS法与外标法测定结果间无显著性差异,证明该法可用于番石榴叶6种黄酮类成分的定量分析。

8个番石榴品种的转录组测序

【目的】获得番石榴转录本数据,探讨不同番石榴品种转录本之间差异。【方法】研究通过Illumina HiSeq 2500平台对红心(HX)、彩虹(CH)、紫红(ZH)、水晶(SJ)、秀珍(XZ)、彩叶变(CYB)、彩叶(CY)和紫星(ZX)等8个番石榴品种的8~9成熟果肉进行转录组测序,通过组装及数据库比对,获得大量番石榴转录本注释信息。【结果】组装获得了126979条Unigene,平均长度766 bp,N_(50)为1654 bp,N_(90)为267 bp;8个番石榴品种间共有27274个基因为共表达基因。通过主成分分析与差异基因表达聚类分析,发现品种水晶(SJ)和彩叶变(CYB)之间基因功能表达差异较小,品种紫红(ZH)与其他品种之间基因表达差异较大。聚类分析将品种水晶(SJ)和彩叶变(CYB)聚为一类,品种红心(HX)、彩虹(CH)、秀珍(XZ)、彩叶(CY)、紫星(ZX)归为一类,但品种紫红(ZH)与其他品种间距离较远。【结论】本研究结果为后续番石榴种质资源分类、功能基因表达、功能基因鉴定提供了大量可靠的转录组数据。

番石榴(Psidium guajava)组织快繁技术的研究

为了进一步研究番石榴组织快繁技术,以番石榴腋芽为外植体研究不同成熟度的腋芽对番石榴芽分化的影响,并进行外植体消毒方法优化以期获得一组最佳的消毒方法组合。结果表明:75%乙醇15 s、1‰氯化汞10 min、75%乙醇10 s消毒效果最好;以较成熟的腋芽作为外植体进行培养的出芽率最高。本研究解决了快繁技术中外植体的选择及木本植物消毒不彻底的问题。