Aloe Saponaria Research Articles

Therapeutic Effects of Aloe saponaria against Ulcerative Colitis Induced by Dextran Sulfate Sodium.

Aloe vera (A. vera) has been studied as a treatment option for ulcerative colitis (UC), but there is a lack of scientific evidence showing whether treatment with Aloe saponaria (A. saponaria) can also be beneficial. To investigate the therapeutic potential of A. saponaria as a treatment for UC, clinical symptoms, histopathological characteristics of the colon, inflammatory response, and toxicity were analyzed in dextran sulfate sodium (DSS)-induced UC mice after administration of aqueous extracts of A. saponaria (AAS) for 7 days. The total polyphenol and tannin content of AAS was 272 µg/g and 163 µg/g, respectively. AAS exhibited significant antioxidant activity. Several clinical symptoms, including body weight, colon length, and hematochezia, remarkably improved in the DSS+AAS treated group compared to the DSS+Vehicle-treated group. In addition, similar improvements were detected in the histopathological characteristics and mucin-secreting ability in the colon of DSS-induced UC mice after the administration of AAS. The levels of infiltrated inflammatory cells and cytokine expression were significantly decreased in a dose-dependent manner in the colon of the DSS+AAS-treated group. These alterations in inflammatory response were accompanied by a significant recovery of the protein kinase C/extracellular signal-regulated kinase (PKC/ERK) and phosphatidylinositol-3-kinase/serine-threonine protein kinase (PI3K/Akt) signaling pathways. However, the levels of key markers for hepatotoxicity and nephrotoxicity consistently remained between those of the DSS+AAS-treated and the No groups. Therefore, the results of the present study provide novel evidence that AAS may improve the clinical symptoms and attenuate the inflammatory response in DSS-induced UC mice and does not have any significant hepatotoxicity or nephrotoxicity.

CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITIES OF TANNINS EXTRACT FROM ALOE SAPONARIA

The objective of this work was to study the chemical composition and antioxidant activity of tannins extract of Aloe saponaria (TEAS). The Aloe saponaria (syn. Aloe maculata) is a succulent plant belonging to the Xanthorrhoeaceae family, this succulent plant native to South Africa was introduced in Morocco as an ornamental plant, rustic and easy to grow. In order to ensure this, morphological and histological study method of the species, phytochemical screening, characterization of TEAS by gas chromatography coupled to mass spectrometry (GC/MS), and the study of antioxidant activity by two methods (2,2-diphenyl-1-picrylhydrazyl (DPPH) and total antioxidant capacity (TAC) assays) were examined. The results of phytochemical screening indicated that the Aloe saponaria leaf was rich of alkaloids, tannins catechics, flavonoids, sterols, triterpenes, oses, holosides, mucilages and reducing sugars. In addition, the main constituents of TEAS identified by GC/MS analysis were Linolenic acid (32.22%), Palmitic acid (17.42%), and Phytol (11.30%). Regarding antioxidant activity, the TEAS showed a significant antioxidant effect.

In vitro evaluation of Aloe saponaria as a potential feed additive to modulate ruminal fermentation and microbial diversity

ABSTRACT Saponin possessed antiprotozoal activity; therefore, it is generally used to mitigate enteric methane (CH4) emission in ruminant nutrition. The objective of this study was to evaluate the effects of Aloe saponaria (AS) supplementation on rumen fermentation, CH4, and microbial diversity in an in vitro experiment over 48 h incubation. Five treatments were used: (1) no additives (CON), 1% and 2% dosage of heat-dried AS (HAS), and freeze-dried AS (FAS), and the experiments were performed three times. After the incubation, volatile fatty acids (VFAs), CH4 proportion in total gas, and microbial diversity were evaluated. Gas production was assessed at 3, 6, 9, 12, 24, 36, and 48 h incubation. FAS addition significantly increased gas production compared to CON except for 6 and 48 h, whereas HAS addition did not significantly affect the gas production at all observed time points. AS addition significantly increased total VFA and the absolute abundances of fungi and Ruminococcus albus regardless of drying method. There was no significant change in the CH4 proportion at 48 h, although the reduction in ciliate protozoa was detected in FAS-treated groups. In conclusion, FAS may be an effective feed additive to improve ruminal fermentation via enhancing feed utilization by rumen microbes.

Isolation of Aloe saponaria-Derived Extracellular Vesicles and Investigation of Their Potential for Chronic Wound Healing.

A chronic wound is caused by a failure to progress through the normal phases of wound repair in an orderly and timely manner. To induce skin regeneration while inhibiting chronic inflammation, numerous natural products, and in particular, plant-derived biomaterials, have been developed. Aloe saponaria, is known to contain flavonoid and phenolic acid compounds with anti-oxidative and anti-inflammatory properties. Here, we isolated extracellular vesicles (EVs) from Aloe saponaria by polyethylene glycol (PEG)-based precipitation and investigated their potential as a therapeutic for chronic wound healing. The Aloe saponaria-derived EVs (AS-EVs) showed no significant cytotoxicity on several cell types, despite a high level of intracellular uptake. When lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages were treated with AS-EVs, significant reductions in the expression of pro-inflammatory genes, such as interleukin-6 and interleukin-1β, were observed. Proliferation and migration of human dermal fibroblasts, as determined by the water-soluble tetrazolium salt-8 and transwell migration assay, respectively, were shown to be promoted by treatment with AS-EVs. It was also demonstrated that AS-EVs enhanced tube formation in human umbilical vein endothelial cells, indicating a stimulatory activity on angiogenesis; one of the crucial steps for effective wound healing. Collectively, our results suggest the potential of AS-EVs as a natural therapeutic for chronic wound healing.

Medicinal plants cultivated in urban home gardens in Heredia, Costa Rica

BackgroundUrban ethnobotanical research in Costa Rica is rather rare and home gardens are poorly studied so far. Investigating their biodiversity is crucial in gathering knowledge on the uses of this particular flora, especially related to the owners’ health. This study therefore explores the diversity and knowledge of medicinal plants of private garden owners from three different urban neighborhoods in Heredia, Costa Rica, an thus far understudied area.MethodsSemi-structured interviews (n = 61) were conducted with garden owners in three socioeconomically different urban neighborhoods (Central Heredia, Maria Auxiliadora and Bernardo Benavides). Information was collected about medicinal plants cultivated in the garden, treatments, plant part used and mode of administration. All species were identified and their geographical origin was determined. This information was then compared with the available regional and local (ethno)pharmacopoeias to detect possible newly documented uses.ResultsThe majority or 90% of garden owners who also held knowledge on medicinal plants species were women (n = 30) of all ages (between 26 and 85 years old). A list of 27 species of medicinal plants was obtained from the participants of three urban neighborhoods. In Central Heredia, 74% (n = 20) of the total species were present, in Maria Auxiliadora 33% (n = 9) and in Bernardo Benavides 56% (n = 15). Most plant species were used by the participants to treat respiratory problems (11 spp.), hair and skin problems (9 spp.) and digestive disorders (8 spp.). Some plants were used to treat multiple ailments (10 spp.). About a third of all species (n = 8) were used by the participants to treat disorders that were not indicated in the regional and local pharmacopoeias. More specifically, Aloe saponaria, Blechum pyramidatum, Costus scaber, Impatiens walleriana, Lippia alba, Tradescantia zebrina, Psidium friedrichsthalianum and Solenostemon scutellarioides used for medicinal purposes by the participants were not found in the above-mentioned resources.ConclusionsThe present study provides new information about the use of medicinal plants in a thus far understudied urban area in Costa Rica. We documented new medicinal uses for several plants listed in the regional and local pharmacopoeias as well as for plants not previously reported in an urban environment. In general, there is little information about the types of plants used for medicinal purposes in urban ecosystems in Costa Rica. Although the country has a high endemic diversity of plants, many exotic medicinal plant species were introduced by the Spaniards during the colonization and by Afro-Costa Rican descendants. The present results thus show how the diversity of the medicinal plants used by these garden owners' confirms a socioeconomic gradient and reflects both Costa Rica’s colonial history as well as the current epidemiological profile of the country. These findings underline the need for more ethnobotanical research in urban areas in Costa Rica.

Improvement of Selected Morphological, Physiological, and Biochemical Parameters of Roselle (Hibiscus sabdariffa L.) Grown under Different Salinity Levels Using Potassium Silicate and Aloe saponaria Extract.

Two successive field trials were carried out at the experimental farm of the Agriculture Department of Fayoum University, Fayoum, Egypt, to investigate the sole or dual interaction effect of applying a foliar spray of Aloe saponaria extract (Ae) or potassium silicate (KSi) on reducing the stressful salinity impacts on the development, yield, and features of roselle (Hibiscus sabdariffa L.) plants. Both Ae or KSi were used at three rates: 0% (0 cm3 L−1), 0.5% (5 cm3 L−1), and 1% (10 cm3 L−1) and 0, 30, and 60 g L−1, respectively. Three rates of salinity, measured by the electrical conductivity of a saturated soil extract (ECe), were also used: normal soil (ECe < 4 dS/m) (S1); moderately-saline soil (ECe: 4–8 dS/m) (S2); and highly-saline soil (ECe: 8–16 dS/m) (S3). The lowest level of salinity yielded the highest levels of all traits except for pH, chloride, and sodium. Ae at 0.5% increased the values of total soluble sugars, total free amino acids, potassium, anthocyanin, a single-photon avalanche diode, stem diameter, fruit number, and fresh weight, whereas 1% of Ae resulted in the highest plant height, chlorophyll fluorescence (Fv/Fm), performance index, relative water content, membrane stability index, proline, total soluble sugars, and acidity. KSi either at 30 or 60 g L−1 greatly increased these abovementioned attributes. Fruit number and fruit fresh weight per plant also increased significantly with the combination of Ae at 1% and KSi at 30 g L−1 under normal soil conditions.

Foliar spray of potassium silicate, aloe extract composite and their effect on growth and yielding capacity of roselle (Hibiscus sabdariffa L.) under water deficit stress conditions

Plants face various abiotic stresses such as drought and salinity during growing stages adversely affect their physiological and biological processes. The use of bioactive compounds could mitigate the detrimental effects of abiotic stresses. The experimental layout was a split split-plot system based on a randomized complete block design with three replications. The treatments included three levels of potassium silicate (0, 3, and 6 cm L-1 or 0, 12, and 24 l-1 of K2SiO3 ha−1) combined with three levels of Aloe saponaria L. extract (Ae) 0, 0.5, and 1% under two levels of irrigation regimes (IR70 and IR100; representing irrigation at 70 and 100% of crop evapotranspiration). The obtained results revealed that control roselle plants were adversely affected by drought, which recorded the lowest growth and yield parameters. Meanwhile, the exogenous addition of Ae and KSi significantly improved the growth and yield of deficit and full irrigated roselle plants. The foliar application of Ae (1%) and KSi (3 or 6 cm L-1) under full irrigation led to a significant increase in growth and yield parameters of roselle. In addition, considerable enhancements in yield quality of roselle plants under deficit irrigation were recorded.

A combined experimental and theoretical study of green corrosion inhibition of bronze B66 in 3% NaCl solution by Aloe saponaria (syn. Aloe maculata) tannin extract

Since antiquity, bronzes have been one of the main cultural heritage metallic artifacts. Currently, they continue to have many applications in various industrial fields. Nevertheless, bronzes are subject to the corrosion process in aggressive environments containing chlorides. To overcome this destructive phenomenon, various conventional protection inhibitors have been developed. Unfortunately, these prevention inhibitors have serious drawbacks are expensive and harmful to human health and the environment. Plant extracts are one of the alternatives that can be used as an ecological, cost-effective and efficient alternative. In this context, Aloe saponaria tannin (AST) extract has been tested as green corrosion inhibitor for bronze B66 in 3% NaCl. The experimental study was conducted by gravimetric and electrochemical measurements, supplemented by surface analysis scanning electron microscopy (SEM) coupled to energy dispersive X-ray spectroscopy (EDX). Which allowed us to highlight the protective effect of our inhibitor. In addition, to investigate the adsorption action of AST compounds over the bronze surface, the theoretical simulations based on the MD (molecular dynamics) and DFT (density functional theory) were done. The electrochemical measurements confirmed the results obtained from the gravimetric measurements and noted that the effect of our inhibitors alters the mechanism of the electrochemical process at the metal/solution interface. The experimental results obtained allowed to note that the AST compounds act as a cathodic type inhibitor. Then, the maximal inhibition efficiency reaches 90% at 150 ​ppm of AST extract. Moreover, the results of theoretical modeling studies supported the adsorption of AST molecules on the target metal substrate.

Determination and Profiling of Secondary Metabolites in Aloe vera, Aloe arborescens and Aloe saponaria

Metabolomics is as an innovative technique for discriminating plant species. The objective of this study was to investigate the secondary metabolites of three different Aloe species, A. vera, A. arborescens, and A. saponaria profiled by 1 H-NMR analysis. Principal component analysis (PCA) derived from the 1 H-NMR spectra indicated a clear discrimination among the Aloe species, providing high predictability and good fitness of the PCA model (R2 = 0.928 and Q2 = 865). As observed in the PLS-DA score plot, discrimination was observed in the Aloe species with respect to primary metabolites including sugar and organic acid and secondary metabolites such as phenylpropanoids and carotenoids. A. vera was characterized by high levels of malate. On the other hand, as compared to the other Aloe species, A. arborescens was characterized by higher levels of aloenin and sugar metabolites such as sucrose and glucose. Furthermore, the secondary metabolites were quantitatively analyzed by HPLC, and the amounts of carotenoids including zeaxanthin, α- and β-carotene, and phenylpropanoids in A. arborescens were found to be significantly higher than those in the other Aloe species. In conclusion, we demonstrated that 1 H-NMR-based metabolomics with chemometric analysis can be used for the facile discrimination of Aloe species.

Chemical Characteristics of Aloe Vera and Aloe Saponaria in Ulsan Korea

The Aloe saponaria plant has been known and used for centuries for its health, beauty, medicinal and skin care properties. On the other hand, Aloe saponaria also contain anti nutrition compounds namely saponin which leads negative effect. Other kind of Aloe known is Aloe vera. The aim of the study was to investigate the saponin content from each part of Aloe plant to maximize it benefits and advantages. In order to know the higher saponin content, this study was comparing between Aloe saponaria and Aloe vera. The saponin content were analyzed from five part of Aloe leaf such as tip of the leaf, middle of the leaf, bottom of the leaf, leaf skin and leaf flesh. To do this, following are done. Total saponin content was identified by extraction. The procedure was performed by modifying the four thermal processing methods by Xu and Chang, 2009. The saponin analysis shows that the skin (S) of the Aloe leaf contains highest concentration of saponin compare to the other part, on both of Aloe species leaf. Those are 1.519±0.048 mg/g for Aloe saponaria and 1.212±0.035 mg/g for Aloe vera respectively. The highest water content obtained in mesophyll tissue (IS). Up to 98% the mesophyll tissue contains with water.

Use of Random Amplified Polymorphic DNA (RAPD) Technique to Study the Genetic Diversity of Eight Aloe Species.

The genus Aloe comprises over 400 species of flowering succulent plants. Aloe leaves are used in the treatment of asthma, gastrointestinal ulcers, cardiovascular disease, tumors, burns, and diabetes. They are rich in anthraquinones, such as aloin, aloe-emodin, chrysophanol, aloinoside A, and aloinoside B. The various species of Aloe show chemical and morphological similarity and diversity, which depend on the genotype and environmental conditions. In a continuity to our interest in the genus Aloe, this study targets the authentication of eight different Aloe species, Aloe vera (A1), Aloe arborescens (A2), Aloe eru (A3), Aloe grandidentata (A4), Aloe perfoliata (A5), Aloe brevifolia (A6), Aloe saponaria (A7), and Aloe ferox (A8), grown in Egypt by using the technique of random amplified polymorphic DNA. Twelve decamer primers were screened in amplification with genomic DNA extracted from all species, of which five primers yielded species-specific reproducible bands. Out of 156 loci detected, the polymorphic, monomorphic, and unique loci were 107, 26, and 23, respectively. Based on a dendrogram and similarity matrix, the eight Aloe species were differentiated from each other and showed more divergence. Aloe species prevailed similarity coefficients of 54-70 % by which they could be classified into three major groups. Thus, this technique may contribute to the identification of these Aloe species that have great morphological similarity in the Egyptian local markets.

Comparison of phytochemical profiles, antioxidant and cellular antioxidant activities of seven cultivars of Aloe

SummaryA comparative assessment of the phytochemical profiles and antioxidant activities of seven cultivars of Aloe was conducted to evaluate the potential health benefits of Aloe. Aloe arborescens contained the highest levels of phenolic content, total antioxidant capacity by the oxygen radical scavenging capacity assay and cellular antioxidant activity assay. Aloe vera showed the highest levels of flavonoid content and antioxidant capacity by the peroxyl radical scavenging capacity assay. Aloe greenii had the highest CAA value with a PBS wash before adding ABAP. There were no significant differences observed between Aloe arborescens and Aloe greenii. Aloin, aloe‐emodin‐8‐O‐beta‐D‐glucopyranoside, catechin, epicatechin, sinapic acid and chlorogenic acid were identified in Aloe samples by the HPLC analysis. Aloin, aloe‐emodin‐8‐O‐beta‐D‐glucopyranoside and catechin showed strong relationships with antioxidant activity. Significant levels of aloin, aloe‐emodin‐8‐O‐beta‐D‐glucopyranoside and catechin were determined in Aloe greenii, Aloe vera and Aloe saponaria, respectively.

Immunomodulatory Effects of Aloe saponaria on Lipopolysaccharide-Activated RAW 264.7 Macrophages

Aloe saponaria (A. saponaria) is composed of a high content of polysaccharides; however, few studies exist on this Aloe species. We analyzed the polysaccharide and protein contents of A. saponaria and found them to be 90% and 3.6%, respectively. A. saponaria reduced nitric oxide production in LPS-stimulated RAW 264.7 macrophages, in addition to decreasing COX-2 mRNA expression. Cytokines, key regulators of the immune response, were specifically regulated in LPS-stimulated RAW 264.7 macrophages treated with A. saponaria in a dose-dependent manner, and the expression of co-stimulatory molecules tended to decrease. The concentration of A. saponaria crude extract required to exert its immunomodulatory activity is high (500-2000 μg/mL). Further studies will need to purify and optimize the dose required for effective immunomodulation.

Anti-inflammatory and antioxidant effects of Aloe saponaria Haw in a model of UVB-induced paw sunburn in rats

Ultraviolet B (UVB) irradiation mainly affects biological tissues by inducing an increase in reactive oxygen species (ROS) production which leads to deleterious outcomes for the skin, including pain and inflammation. As a protective strategy, many studies have focused on the use of natural products. The aim of this study was to investigate the effects of Aloe saponaria on nociceptive, inflammatory, and oxidative parameters in a model of UVB-induced sunburn in adult male Wistar rats. Sunburned animals were topically treated with vehicle (base cream), 1% silver sulfadiazine (positive control) or A. saponaria (10%) once a day for 6days. UVB-induced nociception (allodynia and hyperalgesia), inflammation (edema and leukocyte infiltration) and oxidative stress (increases in H2O2, protein carbonyl levels and lipid peroxidation and a decrease in non protein thiol content) were reduced by both A. saponaria and sulfadiazine topical treatment. Furthermore, A. saponaria or its constituents aloin and rutin reduced the oxidative stress induced by H2O2 in skin homogenates in vitro. Our results demonstrate that topical A. saponaria treatment displayed anti-nociceptive and anti-inflammatory effects in a UVB-induced sunburn model, and these effects seem to be related to its antioxidant components.

알로에 베라(A. vera)와 알로에 사포나리아(A. saponaria)로 부터 효모의 분리 및 계통분석

BACKGROUND: Several yeast species have potential applications in biotechnology and the identification of such yeast species is of great interest. The first step in the identification of yeasts is the establishment of an effective isolation method. Thus, we compared the efficacy of different yeast media in the isolation of yeast associated with Aloe vera and Aloe saponaria. METHODS AND RESULTS: In this study, we spread homogenized A. vera and A. saponaria leaves onto 4 different yeast selective media containing chloramphenicol, streptomycin, Triton X-100 and L-sorbose. We observed high selectivity for yeast and many colonies on media. We isolated 67 yeast strains from A. vera and 42 yeast strains from A. saponaria. We used phylogenetic analysis to identify the yeast isolates based on ITS region sequencing and performed sequence analysis on representative isolates from each agar plate. Further, we compared the sequences obtained with reference sequences. The yeast species isolated from A. vera were as follows: 56 isolates of Meyerozyma, 9 isolates of Cryptococcus, and 1 isolate each of Rhodotorula and Sporobolomyces. Those isolated from A. saponaria were as follows: 41 isolates of Rhodosporidium and 1 isolate of Sporobolomyces. CONCLUSION(S): All the isolates obtained using large agar plate containing chloramphenicol, streptomycin, Triton X-100 and L-sorbose were identified as yeast. Therefore, we concluded that this method is useful for selective screening of yeast species.

Antinociceptive and anti-inflammatory effects of Aloe saponaria Haw on thermal injury in rats

Ethnopharmacological relevanceIn Brazil, the plant Aloe saponaria Haw, popularly known as “babosa pintadinha”, has been empirically used for its potential effect on thermal injury. Because there are no scientific data confirming its popular use, the aim of the present study was to investigate the effects of Aloe saponaria on nociceptive and inflammatory parameters in a rat model of thermal injury. Materials and methodsAdult male Wistar rats were subjected to a thermal injury or sham procedure (immersion in water at 70 or 37°C, respectively, for 5 or 8s). Burned animals were topically treated with vehicle (base cream), sulfadiazine 1% (positive control) or Aloe saponaria cream (0.3%–30%) once a day for 2 or 6 days. Each day, 30min before the treatment, we measured nociceptive (static and dynamic mechanical allodynia, thermal allodynia and spontaneous pain) and inflammatory (paw edema) parameters. Moreover, enzymatic indicators of leukocyte infiltration into burned tissue were also determined 2 or 6 days after the thermal injury. ResultsThe thermal injury (fist and second-degree) procedure, but not the sham procedure, induced nociception and inflammation from 1 to 6 days after the injury. The topical treatment with Aloe saponaria cream (10%) reduced nociceptive behaviors from day 1 to 6 (peak at day 2), edema at days 5 and 6 (peak at day 6) and myeloperoxidase, N-acetyl-glucosaminidase and eosinoperoxidase activities at day 6. The antinociceptive and anti-inflammatory effects of Aloe saponaria were obtained with doses of 3%–30%, with maximal inhibition obtained with a dose of 10% (reductions of 39±9%, 41±9%, 31±7%, 83±7% and 23±2% for static and dynamic mechanical allodynia, thermal allodynia, spontaneous pain and paw edema, respectively). ConclusionOur results demonstrate that topically applied Aloe saponaria presented antinociceptive and anti-inflammatory effects in rats subjected to a thermal injury, which supports its traditional use for burn injuries.

Aloe maculata All. (Asphodelaceae) in the Free State Province, South Africa, and resurrection of ‘var. ficksburgensis’

Although morphologically variable and widely distributed in southern Africa, Aloe maculata All. is well defined by a suite of characters that includes maculate (spotted) leaves, flattopped inflorescences and uniformly coloured flowers. Being a predominantly mild-climate species, it rarely ventures into the more severe southern African interior escarpment, where one of its variants, var. ficksburgensis Reynolds — to date only validly published in combination with the name Aloe saponaria (Aiton) Haw. — occur. We here make the new combination at subspecific level, A. maculata subsp. ficksburgensis (Reynolds) Gideon F.Sm. & Figueiredo, and record its occurrence near Winburg in central South Africa, about 80 km west of previously known records.

Characterisation of gels from different Aloe spp. as antifungal treatment: Potential crops for industrial applications

The leaf characteristics and gel chemical composition of eight Aloe species (Aloe arborescens Mill., Aloe aristata Haw., Aloe claviflora Strydenburg, Aloe ferox Mill., Aloe mitriformis Mill., Aloe saponaria Ait., Aloe striata Haw., and Aloe vera L.) were studied in freshly harvested leaves at three different seasons within the Mediterranean climate: winter, spring and summer. Results revealed that differences existed in leaf properties and chemical composition of the gels of the several Aloe spp. and harvest seasons. The highest gel percentage was obtained from A. vera and A. claviflora (≈62–65%) followed by A. ferox and A. mitriformis (≈50–58%). Harvest season greatly affected gel properties with increases in lipids, proteins, aloin, total phenolics, total antioxidant activity (hydrophilic and lipopihilic fractions) and polyamines (putrescine and spermidine) were obtained in the summer season, whilst they were no differences in leaf characteristics. In addition, the growth potential of fruit pathogenic fungi (Botrytis cinerea, Penicillium digitatum, Penicillium expansum and Penicillium italicum), artificially inoculated on the whole leaves, was evaluated. The highest antifungal activity, measured as absence of or low percentage of infected wounds, was obtained for A. ferox, A. mitriformis and A. saponaria, this antifungal activity being positively correlated with gel aloin content. A. ferox, A. mitriformis and A. saponaria could be good alternatives to A. vera for commercial gels and other practical applications.

Caracterización morfoanatómica comparativa entre Aloe vera (L.) Burm. F., Aloe arborescens Mill., Aloe saponaria Haw. y Aloe ciliaris Haw. (Aloeaceae)

Aloe vera (L.) Burm. F. (= Aloe barbadensis Miller) known as plant of immortality in ancient Egypt is used in phytotherapy as moisturizer, antibacterial, antifungal, antiviral and antioxidant. In Argentina it grows in the form adventitious or cultivated, Aloe arborescens Mill., Aloe saponaria Haw. and Aloe ciliaris Haw. (Aloaceae). In order to contribute to the identification of the drug plant the morphoanatomical characterization of the leaf was carried out. These species were studied with optical microscopy and scanning electron microscopy and the histochemical characteristics were studied in order to identify the active compounds. Morphoanatomical characteristics of these species were determined through lineal and proportional (stomatal index) parameters.

Karyotypic Variability in Experimental Diploid and Triploid Hybrids of Aloe vera*A. saponaria

Cytogenetic traits were examined in Aloe saponaria (2S), A. vera (2V and 4V), and the experimental diploid (VS) and triploid (VVS) hybrids. Karyotype 2n=2x=14 (8L+6S) was confirmed in 2S and 2V, whereas 2n=4x=28 (16L+12S) was ascribed to 4V. VS showed the expected karyotype 2n=2x=14 (8L+6S), with slight differences between the long (L) homologues. VVS also showed the expected karyotype 2n=3x=21 (12L+9S); however, several chromosome deviations reflecting the absence or addition of small (S) chromosomes, terminal deletions of variable size which led to the formation of atypical chromosomes, or the loss of a L chromosome were also observed. The implication of these karyological variations is discussed.