Isolation of Nine Microorganisms from Rotten <i>Dioscorea rotundata</i>(White Yam) and Antimicrobial Sensitivity Test with Five Plant Extracts

Five yam tuber varieties were investigated for microorganisms that cause yam tuber rot from five local government areas of Benue State, Nigeria, between the months of March 2014 to March 2015. Five fungi species: Aspergillus niger, Rhizopus stolonifera, Botryodiplodia theobromae, Fusarium oxysporum, Penicillium marnessei and four bacteria species: Serratia marcescens, Erwinia caro-tovora, Klebsiella oxytoca and Pseudomonas aeruginosa were consistently isolated. Pathogenicity test carried out confirmed these organisms as the pathological agent of the rot. Antimicrobial activity of five plant aqueous extracts: Terminalia catapa (common name fruit), Passiflora edulis (passion fruit), Daniella oliveri (Chiha-Tiv), Ceiba pentandra (Vambe-Tiv), Jatropha tanjorensis (Catholic plant) was carried out on the isolated microorganims and they showed varing degrees of inhibition, the aqueous extract from Passiflora edulis, Ceiba pentandra and Jatropha tanjorensis were able to inhibit all the fungi completely.

Extraction Methods and Inhibition Studies of Ten Plant Extracts on Nine Yam Rot Pathogenic Microorganisms

Nine microorganisms, comprising of four bacteria, Erwinia carotovora, Pseudomonas aeruginosa, Serratia marcescens, Klebsiella oxytoca and five fungi, Rhizopus stolonifera, Aspergillus niger, Aspergillus flavus, Fusarium oxysporum and Penicillium marneffei, isolated from rotten yam tubers of 2016 harvest year, were treated with ten plants extracts (Passiflora edulis, Daniella oliveri, Ceiba pentandra, Jatropha tanjorensis, Azadrichta indica, Carica papaya, Moringa oleifera, Mangifera indica, Terminalia catapa and Senna alata), singly and synergistically by incorporation of extract in media for inhibition test. Two plant extracts singly and completely inhibited the growth of three organisms: Terminalia catapa at 100% and 10-1 showed complete inhibition (a) of Erwinia carotovora. Passiflora edulis at undiluted (100%) concentration completely inhibited Rhizopus stolonifer and Penicillium marneffei, respectively. Synergistic plant extract recorded complete inhibition (a) of all the four bacteria isolates at 2 mL extract incorporation;ten (10) mL extract incorporation in media recorded complete inhibition (a) of three out of the five fungi isolates: Rhizopus stolonifer, Fusarium oxysporum and Penicillium marneffei, respectively;the other two fungi recorded high inhibition (b) of Aspergillus niger and Aspergillus flavus, respectively. Hot aqueous synergistic plants extract recorded poor inhibition of the isolates as compared to the cold. Soxhlet solvent extracted synergistic plants extract, however, recorded lower inhibition as compared to hot aqueous synergistic plants extract and cold aqueous synergistic plants extracts. Room temperature solvent extracted synergistic plants extracts recorded inhibition that was same as that obtained with cold aqueous synergistic plants extract. This research indicates that heat employed extractions recorded less inhibition activity.

Isolation of Six Microorganisms from Rotten <i>Dioscorea alata </i>(Water Yam), and Antimicrobial Sensitivity Test with Nine Plant Extracts

Six microorganisms: four fungi—Aspergillus niger, Aspergillus flavus, Rhizopus stolonifera, Penicillium marneffei, two bacteria—Erwinia carotovora and Pseudomonas aeruginosa were isolated and identified from three rotten Dioscorea alata (water yam) varieties from two sites each in two local government areas of Benue State, Nigeria, in West Africa, between the months of May 2014 and May 2015. Pathogenicity test carried out using the microorganisms confirmed them to be the pathological agents of the rot. Antimicrobial activity test with aqueous extracts of nine plants: Terminalia catapa, Passiflora edulis, Daniella oliveri, Ceiba pentandra, Jatropha tanjorensis, Azadirachta indica, Carica papaya, Moringa oleifera, and Mangifera indica of fresh and dry material showed that three pathogens, Rhizopus stolonifera (fungi), Erwinia carotovora and Pseudomonas aeruginosa (bacteria) isolated were completely inhibited each by a plant. The result obtained shows that Passiflora edulis had the best antimicrobial activity for both fungi and bacteria;indeed it inhibited completely Rhizopus stolonifera which was stubborn with most of the other plants. Azadirachta indica, Carica papaya, Moringa oleifera, and Mangifera indica were also able to inhibit most of the fungi but not completely. Terminalia catapa and Jatropha tanjorensis were most effective against the bacteria. Erwinia carotovora was completely inhibited by Terminalia catapa and Pseudomonas aeruginosa was completely inhibited by Jatropha tanjorensis. Daniella oliveri and Ceiba pentandra had the least inhibition against the isolates. Generally, the fresh plant extract shows more activity as compared to the dry plant extract.

DPPH Radical Scavenging Capacity of Phenolic Extracts from African Yam Bean (<i>Sphenostylis stenocarpa</i>)

The phenolic extracts of the seeds of African yam bean (Sphenostylis stenocarpa) were studied using different extraction solvents (70% ethanol, 80% acetone and acidic 70% acetone) and two heat treatment methods (dry heating on a hot plate with acid-washed sea sand at 135℃ for 25 min and wet heating in an autoclave at 120℃ for 20 min). The study examined the total phenolic content (TPC), total flavonoid content (TFC), and condensed tannin content (CTC) of the seed extracts, as well as their free radical scavenging and antioxidant properties. The raw African yam bean seed was dry heated in air oven at 100℃ for 5 min (control). Heat treatments application affected the phenolic contents of the seeds significantly (p < 0.05). The free radical scavenging activity of the phenolics were done using 2,2-diphenyl- 1-picrylhydrazyl (DPPH). The effectiveness of the extract was determined using DPPH at 50 mg/g, 10 mg/g and 5 mg/g of the extracts. At 5 mg/g, the extract was most effective indicating that higher concentration of extract gave higher antioxidant activity. The seed has high antioxidant capacity and an appreciable amount of phenolic extracts.

Postharvest Loss Control: Synergistic Plants Extract Inhibition of Ten Microbial Yam Rot Organisms

Nine microorganisms were isolated from four varieties of Dioscorea rotundata (gbongu, ogoja, Amula, Hembamkwase);four bacteria, Erwinia carotovora, Pseudomonas aeruginosa, Serratia marcescens, Klebsiella oxytoca and five fungi, Rhizopus stolonifera, Aspergillus niger, Aspergillus flavus, Fusarium oxysporum, Penicillium marneffei, from five local government areas of Benue State (Vandeikya, Ukum, Katsina Ala, Guma and Logo). Pathogenicity test on the isolates confirmed them to be the cause of rot. The nine plants extract (Ceiba pentandra, Jatropha tanjorensis, Azadirachta indica, Moringa oleifera, Carica papaya, Mangifera indica, Daniella oliveri, Terminalia catapa and Passiflora edulis) synergistically added inhibited all the four bacteria isolates completely. The five fungi were inhibited by 60% (c) - 80% (b);Rhizopus stolonifera, Aspergillus flavus, Fusarium oxysporum;and Aspergillus niger, Penicillium marneffei, respectively.

Acetone Extract of <i>Dioscorea alata</i>Inhibits Cell Proliferation in Cancer Cells

Dioscorea spp., White Yam has been shown to exhibit a wide range of nutritional and medicinal properties. However, the compounds associated with its medicinal functions have not been fully examined. The purpose of this study was to generate a chemoinformatic profile of the bioactive compounds present in Dioscorea. alata (D. alata) and to characterize their putative anti-cancer properties using prostate (DU145) and lung (A549) cancer cells. Chemoinformatic profiling of D. alata resulted in five bioactive extracts: hexane (DaJa-1), ether (DaJa-2), acetone (DaJa-3), ethanol (DaJa-4) and water (DaJa-5) were generated. The analytes present in the five bioactive extracts were dissolved in 0.1% DMSO and their anti-cancer activity were determined. We observed that the acetone extract (DaJa3) was the only extract capable of inducing greater than 90% cell death of DU 145 cell at 100 μg/mL. The order of growth inhibition of the extracts in DU-145 cell is DaJa-3 (IC50, 31.45 μg/mL) > DaJa-4 (IC50 60 μg/mL) > DaJa-1 (IC50 > 100 μg/mL) ≥ DaJa-2 (IC50 > 100 μg/mL) ≥ DaJa-5 (IC50 > 100 μg/mL). MTT cell viability, dye exclusion, caspase activity and microscopic assessment of apoptotic cells demonstrated that DaJa-3 displayed cytotoxicity to both lung and prostate cancer cells. The A549 cells were more sensitive toward DaJa-3 with an IC50 value of 22.28 μg/mL (CI 28.42 to 36.63 μg/mL), compared to that of DU145 cells with an IC50 value of 31.45 μg/mL (CI 27.58 to 35.86 μg/mL). It was also observed that DaJa-3 induces differential anti-proliferative activity in the cancer cells. The apoptotic response induced by DaJa-3 paralleled the level of cell cytotoxicity observed in both cell lines. DaJa-3 induces G2 phase cell cycle arrest in DU145 cells but G1 arrest in A549 cells. The level of key apoptotic regulator proteins was upregulated, suggested that DaJa-3 may be mediating its anti-cancer effect through activation of the intrinsic apoptotic pathway. Altogether, our data indicates that DaJa-3 derived from a staple food source (white Yam) contains unique active compounds that have specific biological properties that may prevent certain types of cancer or specific types of cancer.

山药多糖药理作用及提取技术研究进展

山药是传统的药食两用物质,在我国具有悠久的食用历史,被广泛应用于食品、医药、畜牧等行业。山药多糖作为山药的主要化学成分,因具有多种生物活性,如免疫调节、抗肿瘤、降血糖、降血脂、抗氧化、抗炎等而受到广泛关注。基于此,总结了山药多糖的结构及其种类,从免疫调节活性、抗肿瘤活性、降血糖和降血脂活性、抗氧化活性、抗炎和抗菌活性等方面对近些年关于山药多糖药理活性的研究进行综述,并对山药多糖的提取技术进行汇总,最后从提取纯化技术、结构表征技术、临床应用试验等方面进行了展望,为山药多糖组分的未来研究与应用提供参考。

山药多糖提取工艺优化及其抗菌活性研究

目的优化山药多糖的提取工艺,并对其进行抗菌活性研究。方法以提取时间、超声波功率、提取温度为自变量,山药多糖得率为因变量,利用响应面法优化山药多糖的提取工艺。并采用纸片法对山药多糖进行抗菌活性研究。结果山药多糖的最佳提取工艺为提取时间108.14 min,超声波功率414.66 W,提取温度80.54℃,山药多糖理论提取率为3.21%,验证值为3.154%。抗菌实验表明,山药多糖对金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌、白色念珠菌属于中敏感,对肠炎沙门氏菌属于低敏感。结论采用星点设计-响应面法优化山药多糖的提取工艺方法简便,预测性好,合理可行。

紫山药提取物抗氧化与延长寿命作用的研究

目的:探究紫山药提取物(Purple yam extract,PYE)抗氧化活性与延长寿命作用。方法:将2 d龄雌性果蝇随机分成4组,在其培养基中分别添加不同浓度(0、0.5、2.0、4.0 mg/m L)PYE。研究PYE对果蝇寿命,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和丙二醛(MDA)等抗氧化酶活力及抗氧化相关基因表达的影响;通过急性实验研究PYE对果蝇氧化应激损伤的影响。结果:与对照组相比,2.0、4.0 mg/m L PYE能显著延长果蝇的寿命(p<0.05);2.0、4.0 mg/mL PYE能显著提高SOD、CAT活力(p<0.05),显著降低MDA含量(p<0.05);2.0、4.0 mg/m L PYE能显著上调SOD、CAT mRNA表达水平(p<0.05),Methuselah(MTH)mRNA表达水平显著下调(p<0.05);急性实验中PYE组果蝇的寿命明显延长。结论:PYE在体内具有较强的抗氧化作用,并可能通过上调抗氧化基因的表达实现延长果蝇寿命的作用。

山药总皂甙的提取研究

本文以山药中总皂甙提取率为考察指标,应用单因素试验和正交设计对山药总皂甙提取工艺中的浸提温度、乙醇的体积分数、浸提时间、料液比进行了研究。以薯蓣皂甙为标准,香草醛-高氯酸为显色剂,冰醋酸为溶剂,用分光光度计在波长为544 nm处对山药总皂甙的含量进行了测定。得出山药总皂甙的最佳提取工艺条件是:浸提温度为60℃,浸提时间为6 h,乙醇体积分数为80%,料液比为1∶8。

黄姜提取薯蓣皂甙元及葡萄糖的工艺研究

薯蓣皂甙元是黄姜中的主要活性成分 ,如何提高其得率和处理其水解滤液一直是实际生产中存在的问题。本文探讨了从黄姜水解液中同时得到薯蓣皂甙元和葡萄糖的提取工艺 ,首次提出了以中和作为主要脱盐方法从黄姜水解滤液中提取高纯度葡萄糖的工艺 ,确定了合适的中和、脱色和脱盐条件。结果表明 ,该工艺优于传统的薯蓣皂甙元提取方法 。

紫山药色素的提取工艺及抗氧化性能研究

研究紫山药色素的最佳提取工艺及其抗氧化性能。在单因素试验的基础上,采用L9(34)正交试验法,以pH示差法测定花色苷得率为考察指标,优化了溶剂提取法提取紫山药色素的工艺参数。通过DPPH体系测定该色素清除自由基能力。试验结果表明:紫山药色素属于花色苷类物质,优化的紫山药色素提取条件为:提取温度60℃,提取时间80 min,料液比1∶30,提取溶剂为0.5%盐酸乙醇溶液,提取液花色苷含量可达2.075mg/鲜紫山药g。紫山药色素提取液清除DPPH自由基的IC50为98.14μg/mL。紫山药具有开发功能性色素的潜力。

山药多糖提取与纯化工艺研究

以市售怀山药为原料,经超声破壁处理,单因素试验考察水提温度、超声波功率、水提时间、料液比对提取后山药多糖含量的影响;采用正交试验对提取工艺进行优选,确定山药中多糖提取的最佳条件;通过DEAE和Sephadex G-100柱层析纯化山药多糖。结果表明,山药多糖提取的最佳条件为:水提温度60℃、超声波功率200W、水提时间30min、料液比1∶16。柱层析纯化后得到山药多糖单一组分。

山药多糖提取分离工艺的研究

通过正交实验对山药多糖的热水浸提和分离方法进行了研究,得到的工艺优化参数为:浸提时间是90 min,浸提温度90℃,料水比为1:5 g/mL。借助微波辅助提取和超声波辅助提取方法,可得到更高的产率。比较了Sevage法及三氯乙酸沉淀法,结果表明用Sevage法进行山药多糖脱除蛋白质效果更好。

紫山药主要活性成分提取纯化技术研究进展

紫山药富含天然花青素、多糖、薯蓣皂苷、多酚、尿囊素等生物活性成分,因此具有抗氧化、免疫调节、耐缺氧、抗衰老等保健功能。归纳整理了紫山药活性成分的研究现状,对紫山药花青素、多糖、薯蓣皂苷、尿囊素等的性质、提取、分离纯化技术研究进展进行综述,以期为我国紫山药的综合开发利用提供参考。

应用生物酶法提取黄姜皂素的清洁工艺研究

文章采用生物复合酶法对薯蓣皂素进行提取研究,使黄姜淀粉和纤维素得到充分降解,促进葡萄糖与皂素的分离,从而有利于黄姜皂素的提取。通过正交实验进行试验确定复合酶处理黄姜皂素的工艺,即最适酶解条件为温度55℃,pH值4.0,时间6h,每克黄姜酶用量为0.03g,通过该条件进行试验发现,黄姜皂素收率提高26%。同时该工艺与传统的直接酸水解法相比,用量酸减少了74.7%,废水总量和COD浓度分别下降了64.1%、89.6%,且产品熔点高。该工艺具有作用条件温和,减少污水排放量、提高皂素得率、污染小、节约能源的特点,可显著降低黄姜皂素生产中污水排放造成的环境污染难题,是一项清洁生产工艺,具有较好发展前景。

响应面法优化山药皮中皂苷提取的研究

皂苷具有抗炎解毒等作用,而山药加工过程丢弃的山药皮中含丰富的皂苷;研究采用超声波萃取技术从山药皮中提取总皂苷并测定其含量,为了优化山药皮中总皂苷的提取工艺,在单因素试验基础上,采用响应面法建立了山药皮中总皂苷提取方法的二次多项数学模型,并验证了该模型的有效性;探讨了料液比、浸热温度、乙醇体积分数3个因子的交互作用及其最佳水平。研究结果表明:提取温度、时间和水料比显著影响其提取效果,优化的山药皮中总皂苷提取条件为:料液比1∶9、浸提温度64℃、乙醇体积分数83%,皂苷的最大提取率为0.129%。

黄姜皂素提取工艺研究

以黄姜为原料,研究皂素提取的生产工艺。通过对几种工艺的比较,确定一种先分离黄姜中纤维素及淀粉,再经过酸水解、中和提取皂素的方法。该法黄姜皂素的平均得率为传统方法的86.56%,用酸量仅为传统方法的9.62%,同时分离得到46.44%的纤维素和32.75%的淀粉。该法资源综合利用率明显提高,并大幅度减少废水的生成,减少环境污染,节约原料、能源,生产周期也明显缩短。

有机山药中多糖及其他成分的含量测定

目的测定有机山药中多糖、脂肪、浸出物含量及折干率。方法以硫酸-蒽酮为显色剂,采用分光光度法测定有机山药中多糖的含量;采用索氏抽提法,测定有机山药中脂肪的含量;采用重量法测定机山药中浸出物含量及折干率。结果多糖在203.8~662.4μg/mL浓度范围内线性良好(r=0.999 3),精密度、稳定性、重现性的RSD均<5.00%,加样回收率为100.7%,有机山药中多糖含量为28.32%,脂肪含量为1.30%,折干率为12.80%,水浸出物为23.62%,醇浸出物为9.67%。结论多糖测定方法简单易行,稳定可靠;有机山药的脂肪和浸出物含量符合国家药典规定,为建立有机山药的质量标准提供依据。

纤维素酶法提取山药多糖的工艺优化

利用响应面法优化了纤维素酶法提取山药(Dioscorea opposita Thunb)多糖的工艺条件。在单因素试验的基础上,采用响应面法对提取时间、提取温度、p H 3个因素进行优化,建立了山药多糖提取率的二次回归方程,通过响应面分析及岭嵴分析得到最优提取工艺为料液比1∶20(m/V,g∶m L),加酶量12 U/g,提取温度42℃、提取时间163.5 min,p H 4.09,该条件下山药多糖的提取率为6.082%。