Evaluation of the Efficacy of an Aloe barbadensis Based Biological Insecticide against Pests of Abelmochus esculentus for Promoting Ecological Agriculture (Far-North, Cameroon)

Chemical insecticides have been considered as a means to combat crop pests. Although their effectiveness is evident, their impact on the environment is increasingly being discussed. The aim of this study is to determine the agro-ecological potential of a biological insecticide (C25H32O12) based on Aloe barbadensis in a Sahelian context. For this purpose, a completely randomized block experimental design with 3 replications and 4 treatments was set up to experiment with Aloe barbadensis as a bioinsecticide against pests of Abelmoschus esculentus. However, data were collected using an observation and parameter monitoring grid. This includes the cultivation of Abelmoschus esculentus, soil preparation, seeding and watering, plot labeling, preparation of the bioinsecticide (selection and preparation of raw materials, grinding of Aloe barbadensis miller and extraction of the crude bioinsecticide, quantification of treatment doses and dilution, and obtaining the formulated bioinsecticide), plant watering, plant treatment, and finally parameter monitoring. The results obtained reveal that the level of damage is significantly high in the control treatment T0 (63%) compared to the other treatments, with 29% for treatment T1, 7% for T2, and 1% for T3, implying a strong action capability of this insecticide against pests of Abelmoschus esculentus. Therefore, it can be concluded that for a normal growing season of Abelmoschus esculentus, this biological insecticide should be sprayed 12 times. Furthermore, this biological insecticide is unique in that it does not inflict any gastric toxicity on the pests, which gives it the characteristic of being a repellent. It is a biological insecticide whose efficacy period has been tested, with a minimum duration of 21 days. In conclusion, this formulated bioinsecticide based on Aloe barbadensis demonstrates significant efficacy against pests of Abelmoschus esculentus. In the future, we will consider experimenting with its effectiveness against pests of other plants.

Relationship Between Leaf Structure and Aloin Content in Six Species of Aloe L.

The leaf structure, content and the storage location of aloin in the leaves of six species of Aloe L. were studied by means of semi-thin section, high performance liquid chromatography (HPLC) and fluorescent microscope. Results showed that all leaves consisted of epidermis, chlorenchyma, aquiferous tissue and vascular bundles. The leaves had the xeromorphic characteristics, including thickened epidermal cell wall, thickened cuticle, sunken stomata and well-developed aquiferous tissue. With the exception of thus, there were remarkable differences in leaf structure among the six species. The chlorenchyma cells were similar to palisade tissues in Aloe arborescens Mill. and A. mutabilis Pillans, but isodiametric in A. vera L., A. vera L. var. chinensis Berg., A. saponaria Hawer and A. greenii Bali. A. arborescens, A. mutabilis, A. very and A. vera var. chinensis included large parenchymatous cells at the vascular bundles, whereas no such cells were observed at the vascular bundles of A. saponaria and A. greenii. In A. arborescens, A. mutabilis and A. vera, the aquiferous tissue sheaths were present and composed of a layer of small parenchymatous cells without chloroplasts around the aquiferous tissue. While there were no aquiferous tissue sheaths in A. vera var. chinensis, A. saponaria and A. greenii. The HPLC revealed that the content of aloin was high in A. arborescens, low in A. vera, and very low in A. saponaria among the six species. The fluorescent microscopy showed that the yellow-green globule only appeared in the large parenchymatous cells of vascular bundles, vascular bundle sheath and aquiferous tissue sheath, but not in the chlorenchyma and aquiferous tissue. Consequently, the large parenchymatous cells of vascular bundles, vascular bundle sheath and aquiferous tissue sheath were the storage location of aloin. They were positively correlated with the content of aloin.

Genetic Transformation of Aloe barbadensis Miller by Agrobacterium tumefaciens

Despite the importance of aloe in cosmetic and pharmaceutical industries, improvement of aloe （Aloe barbadensis Miller） by genetic engineering was seldom reported previously. In this study, regeneration and transformation conditions, including explant selection and surface sterilization, use of different Agrobacterium strains, and co-culture processing, are optimized. The use of 20.0% sodium hypochloride （25 rain） for sterilization was less detrimental to the health of explant than 0.1% mercuric chloride （10 min）. Regeneration frequency from stems was much higher than that from leaves or sheaths. Explants were infected by Agrobacterium （30 rain） in liquid co-cultural medium, and this was followed by three days co-culture on sterile filter papers with light for 10 h per day at 24℃. Histochemical data demonstrated that the transient expression of GUS gene in the stem explants of aloe infected with Agrobacterium strains EHAI05 and C58CI was 80.0% and 30.0%, respectively, suggesting the higher sensitivity of the explants to EHAI05 than to C58C1. Infected tissues were selected using G418 （10.0-25.0 mg/L） to generate transformants. Sixty-seven G418 resistant plantlets were generated from the infected explants. Southern blotting, PCR, and ELISA analyses indicated that the alien gene were successfully transferred into aloe and was expressed in the transgenic plants. This newly established transformation system could be used for the genetic improvement of aloe.

The Action of Aloe Anthraquinones in Protecting the Growth of Soybean from Ultraviolet Radiation Stress

In order to investigate the protective effect of aloe anthraquinones on growth and development of soybean against ultraviolet B radiation stress from the morphological structure and physio-chemical indices. The results showed that, stressed by the enhanced ultraviolet b radiation, the soybean gave a dwarfed plant, shrunken leaf area and decreased photosynthetic pigment, while an ascended MDA content. Spraying aloe anthraquinones effectively relieved the reductions of chloro- phyll content and biomass and decreased the production of MDA under the radia- tion of UV-B. Moreover, under the UV-B radiation, waxy substances on epidermal cells increased remarkably and the stomas showed obvious subsidence, while spraying aloe anthraquinones could maintain the structure and shape of cells similar to that under natural light, and the stomas subsidence as well.

长期盐胁迫对库拉索芦荟(Aloe vera)生长和汁液理化性质的影响

在温室中砂培条件下研究了7叶龄库拉索芦荟(Aloe vera)以含0、50、100、200和400 mmol L-1NaCl的Hoagland营养液浇灌120 d的生长响应及其全叶原汁的理化性质。结果表明:200 mmol L-1NaCl处理显著抑制芦荟生长,使叶片长度、宽度、厚度和重量显著减小,含水量和叶绿素含量降低,干枯死亡的叶片数显著增多,根系周界和根系密集区显著缩小,单株干重降至对照的65.02%,单株鲜重只及对照的38.32%,至开花期花葶低矮、细弱,开花株数明显减少;100 mmol L-1NaCl处理对库拉索芦荟生长的抑制作用显著减轻,且可正常开花,花期未见缩短,但至处理结束时新叶的长度,处理结束时单叶的厚度和鲜重、根系密集区范围以及叶片和全株的鲜重、根系的干重和鲜重均显著小于对照,而50 mmol L-1NaCl处理与对照无显著性差异。盐胁迫对库拉索芦荟全叶原汁出汁率及理化性质的影响与对生长开花的影响相似,其中501、00 mmol L-1NaCl处理间多数指标值无显著性差异,与对照相比多数指标值处于有益水平。综合评判:库拉索芦荟具有咸水微咸水灌溉栽培的潜势。

Anatomy, Histochemistry and Phytochemistry of Leaves in Aloe vera var. chinensis

A multidisciplinary approach-anatomy, histochemistry and phytochemistry-was used to investigate the leaf structure, the content and the storage location of barbaloin in the leaves of Aloe vera L. var. chinensis (Haw.) Berg. Xeromorphic characteristics including secondary thickened epidermal cell walls, thicker cuticle, ambiguous differentiation of spongy and palisade tissues in the chlorenchyma, and well-developed aquiferous tissue could be seen in the leaves. Several large parenchymatous cells were observed at the phloem pole of the first ring of vascular bundles. The secondary ring of vascular bundles in the leaf base and the stomata, which are surrounded by five cells, have some classification significance in this species. The density of vascular bundles, the content of barbaloin and the intensity of histochemical reaction differed among leaf numbers Ll (annual leaf), L2 (biennial leaf), L3 (triennial leaf) and L4 (quadrennial leaf), and in different parts of the leaf. These three factors were highest in the youngest leaf, Ll, and top parts of all the leaves and lowest in the basal parts and the oldest leaf, L4. The density of vascular bundles had a positive correlation to the content of barbaloin. The histochemical results revealed that the small sheath cells that surrounded the bundles might be the location of barbaloin synthesis and the large parenchymatous cells beneath the sheath might be the storage places of this metabolite.

活性炭在库拉索芦荟(Aloe vera)的组织培养中的应用

探索了库拉索芦荟组织培养中活性炭(AC)的添加量与植物激素添加量的关系以及对库拉索芦荟外植体出芽率的影响。结果表明,在MS固体培养基中,活性炭对植物激素的吸附量不能简单地套用MS液体培养基中的吸附量,活性炭的吸附作用情况较复杂;库拉索芦荟外植体出芽的较好培养基为MS+6 BA3mg/L+NAA0 2mg/L+AC0 2%和MS+6 BA5mg/L+NAA0 2mg/L+AC0 4%。

影响库拉索芦荟(Aloe vera L.)愈伤组织诱导的因素

比较了不同培养基对库拉索芦荟愈伤组织的诱导效果,其中B5+6 BA2.0mg/L+2,4 D2.0mg/L+Vc5.0mg/L培养基出愈率较高,愈伤组织褐化较轻.探讨了抑制库拉索芦荟愈伤组织褐化的方法.

芦荟库拉索(Aloe vera L)再生体系的建立

对芦荟(AloeveraL.)组织培养和再生体系进行了研究,初步获得芦荟的初代和继代培养基为MS+6-BA2.5mg/L+NAA0.2mg/L+蔗糖30mg/L,生根培养基成分为1/2MS+IBA0.2mg/L+NAA0.1mg/L+蔗糖30mg/L,愈伤组织培养采用粗壮的芦荟基部的白色部分,诱导愈伤组织的培养基为B5+6-BA2.0mg/L+2,4-D2.0mg/L+蔗糖30mg/L,采用Vc5.0mg/L抑制愈伤组织诱导过程中褐变的产生。诱导愈伤组织和外植体直接出芽2种方式并存。试管苗移栽后存活率为100%。采用潮霉素为抗性筛选标记,选择浓度为20￣30mg/L。

六种芦荟属(Aloe L.)植物的形态特征及生物学特性描述

文章对6种芦荟属 (AloeL .)植物和1种十二卷属 (HaworthiaDuval.)植物的外部形态学特征及其生物学特性进行了详细描述 。

Determination of Barbaloin in Aloe vera L. var. chinensis (Haw.) Berger and Aloe barbadensis Miller by HPLC

A reserved-phase HPLC method was developed for the determination of barbaloin in Aloe vera L. var. chinensis (Haw.) Berger and Aloe barbadensis Miller, and whether there was a close relationship between the contents of barbaloin and their environments in which they were growing was decided. A Hypersil ODS column (4.6 mm×200 mm, 5 μm)was used with a mobile phase of methanol-water (40:60, containing 0.1% acetic acid), the flow rate being 1.0 mL·min -1, detection wavelength at 359 nm, and the column temperature being 30℃. The linear range of barbaloin was between 0.0726 and 0.726 μg with a correlation coefficient of 0.9998 and the regression equation being Y=1.9202×10 6X-1801.9. Barbaloin was stable in methanol in 48 h and the instrument precision was 1.2% while the method precision was 4.9%. The contents of barbaloin of 12 samples ranged from 6.160 to 319.1 μg·g -1. The method developed was fast and simple with good reproducibility. There was high correlation between the contents of barbaloin and their growing environments.

华芦荟(Aloe.chinensis)和元江芦荟(Aloe.yuanjiangensis)种名确定的探讨

文章对芦荟属(AloeL.)分类地位进行描述,并对华芦荟[Aloe.chinensis(Haw.)Baker]和元江芦荟(A.yuanjiangensisXiong,ZhengetLiu)种名的确定进行阐述。

芦荟(Aloe arborenscens)叶片细胞部分超微结构生物电子显微镜技术的观察

文章通过对芦荟叶片细胞TEM常规样品制备技术,EM负染色技术,Meltshadow技术,SEM常规样品制备技术的生物电镜应用,在光学显微镜结构观察的基础上,观察了芦荟叶片表皮的各种附属结构,芦荟叶片细胞的细胞壁、细胞膜的结构与位置,叶片细胞的液泡、叶绿体、线粒体和核仁的形状及结构等。观察结果表明,芦荟叶片表面有蜡质层包被,且分布均匀;叶绿体呈棒状,内有丰富的片层结构;核仁呈圆球状,染色质深而密集;线粒体呈长圆球形,内膜腔内充满了透明的胶体状态物质。

芦荟属(Aloe L.)植物有性杂交试验的研究初报

文章用芦荟属(Aloe L．)植物元江芦荟(A．yuanjiangensis Xiong,Zheng et Liu)和皂质芦荟[A．saponaria(Ait．) Haw．]为亲本进行了种间远缘有性杂交试验,获得了19株F1代实生苗。对F1代实生苗的外部形态特征的初步鉴定结果表明,F1代出现了明显的分离,并产生了兼有父母本优良特征的中间类型10株,占52．63％,达到育种目标的有8株,占 42．11％。旨在探索芦荟属植物杂交育种的方法与途径,培育具有更高经济价值的芦荟新品种,丰富我国的芦荟种质资源。

铝-水反应制氢副产物AlO(OH)的回收及阻燃利用

针对制氢用活性铝合金水解产物中除气态H 2外,还有固态副产物AlO(OH)等的回收和再利用问题。以自制AlO(OH)阻燃添加剂,与聚丙烯(PP)熔融共混制备AlO(OH)/PP复合材料。采用极限氧指数测定仪、热重分析仪、差示扫描量热仪对AlO(OH)/PP复合材料的阻燃性能、热稳定性和结晶行为进行研究。结果表明:随着AlO(OH)从0增加到25%,极限氧指数(LOI)和热稳定性提升,熔滴的滴落得到抑制。AlO(OH)为25%时复合材料的LOI较纯PP提升了29.2%,复合材料结晶峰值温度增加、结晶度下降,自制AlO(OH)具有阻燃效果。

Aloesin as a medical food ingredient for systemic oxidative stress of diabetes

Diabetes is a chronic disease that requires a long term management where oxidative stress plays a pivotal role in disease progression and intensifying secondary complications. In spite of all the research on diabetes and recent advances in diabetes treatments, the reality is that there is no cure for diabetes and its devastating complications. While currently available anti-diabetic therapies are effective in reducing blood glucose level, they are not without associated side effects when they are used for a long term applications. As a result, physicians and patients are inclining more towards to a safer therapy with less serious side effects in the form of medicinal foods and botanical alternatives that are suitable for chronic usage. Aloesin, an Aloe chromone, has previously been formulated with an aloe polysaccharide to give a composition called Loesyn, where it showed significant impact in reducing glycosylated hemoglobin, fasting blood glucose, fructosamine and plasma insulin level in humans. Radical scavenging activities of chromones and polysaccharides from Aloe have also been reported. Here we rationalize the relevance of use of Aloesin alone or in a standardized blend with Aloe polysaccharides, as a potential medical food to manage systemic oxidative stress and/or high blood glucose of diabetes.

Low-temperature green synthesis of boron carbide using aloe vera

The unique structural and physical properties of boron carbide, which make it suitable for a wide range of applications,demands the development of low-cost and green synthesis method. In the present work, the commonly available leaves of aloe vera are hydrothermally treated to form the carbon precursor for the synthesis of boron carbide. The morphological characterization reveals the porous nature of the precursor turning into a tubular structure upon boron carbide formation.The structural characterization by x-ray diffraction and other spectroscopic techniques such as Fourier transform infrared,Raman, photoluminescence and uv-visible near-infrared spectroscopy confirm the formation of boron carbide. The thermogravimetric analysis of the sample is found to exhibit good thermal stability above 500 °C. When the sample is annealed to 600 °C, boron carbide with phase purity is obtained, which is confirmed through XRD and FTIR analyses. The optical emission properties of the sample are studied through CIE plot and power spectrum. Compared with other natural precursors for boron carbide, the aloe vera is found to give a good yield above 50%.

Stress Effect of Cadmium Absorption between Aloe and Solanum nigrum L

The stress effect of cadmium absorption between aloe and Solanum nigrum L was studied through a simulation experiment with different cadmium contents in soil. The results showed that the growth characteristics, biomass and Cd content in the plants of aloe and S. nigrum L were closely related to Cd content in the soil, and S. nigrum L and aloe had a strong tolerance to Cd in the experiment, pH of rhizosphere soil with S. ni- grum L and aloe planted was generally higher than that of non-rhizosphere soil, which is related to the planting pattern. Compared with aloe, S. nig- rum L had a stronger capacity to accumulate Cd, and intercropping S. nigrum L and aloe could inhibit aloe＇s absorption of Cd, which is favorable to the safe planting of aloe. In addition, S. nigrum L has the potential to restore polluted soil.

Anticancer activity of Aloe vera and Calligonum comosum extracts separetely on hepatocellular carcinoma cells

Objective: To investigate the in vitro anticancer effect of Aloe vera(A. vera) and Calligonum comosum(C. comosum) extracts against hepatocellular carcinoma(HepG 2) cells. Methods: Hep G2 cells were tested against different doses of A. vera and C. comosum. Viability of the cells was assessed by MTT assay. Evaluation of apoptosis and DNA damage in HepG 2 cells were performed using annexin V apoptosis detection kit. The expression of p53 and anti-apoptotic(Bcl-2) were tested by real time-PCR and flow cytometer analyser. Hematoxylin and eosin stained sections from untreated and treated HepG 2 cells were observed using light microscopy.Results: The IC50 values of A. vera and C. comosum extracts were(10.45 ± 0.31) and(9.60 ± 0.01) μg/mL respectively. The extracts separately increased cytotoxicity against HepG 2 cells in a time and dose dependent manners. Also, it apparently induced apoptosis through increase P53 and decrease Bcl-2 genes expressions.Conclusions: The results indicated that the extracts could have anti-hepatocarcinogenic effect, at least in part, through modulation of apoptosis.

Effects of Aloe vera and sucralfate on gastric microcirculatory changes,cytokine levels and gastric ulcer healing in rats

AIM： To compare the effects of Aloe vera and sucralfate on gastric microcirculatory changes, cytokine levels and gastric ulcer healing. METHODS： Male Spraque-Dawley rats （n=48） were divided into four groups. Group 1 served as control group, group 2 as gastric ulcer group without treatment, groups 3 and 4 as gastric ulcer treatment groups with sucralfate and Aloe vera. The rats from each group were divided into 2 subgroups for study of leukocyte adherence, TNF-α and IL-10 levels and gastric ulcer healing on days 1 and 8 after induction of gastric ulcer by 20% acetic acid. RESULTS： On day 1 after induction of gastric ulcer, the leukocyte adherence in postcapillary venule was significantly （P〈 0.05） increased in the ulcer groups when compared to the control group. The level of TNF-α was elevated and the level of IL-10 was reduced. In the ulcer groups treated with sucralfate and Aloe vera, leukocyte adherence was reduced in postcapillary venule. The level of IL-10 was elevated, but the level of TNF-a had no significant difference. On day 8, the leukocyte adherence in postcapillary venule and the level of TNF-α were still increased and the level of IL-10 was reduced in the ulcer group without treatment. The ulcer treated with sucralfate and Aloe vera had lower leukocyte adherence in postcapillary venule and TNF-α level. The level of IL-10 was still elevated compared to the ulcer group without treatment. Furthermore, histopathological examination of stomach on days 1 and 8 after induction of gastric ulcer showed that gastric tissue was damaged with inflammation. In the ulcer groups treated with sucralfate and Aloe vera on days 1 and 8, gastric inflammation was reduced, epithelial cell proliferation was enhanced and gastric glands became elongated. The ulcer sizes were also reduced compared to the ulcer group without treatment. CONCLUSION： Administration of 20% acetic acid can induce gastric inflammation, increase leukocyte adherence in postcapillary venule and TNF-α level and reduce IL-10 level. Aloe vera treatment can reduce leukocyte adherence and TNF-αlevel, elevate IL-10 level and promote gastric ulcer healing.