Use Of Cymbopogon Citratus Leaf Essential Oil For Management Of Anthracnosis In Yam-Grops

The essential oil of Cymbopogon citratus (DC.) Stapf. (Lemongrass) has been positioned as a phytosanitary alternative to counteract the effects caused by phytopathogenic fungi. The aim of the present study was to evaluate in vitro the inhibitory activity of essential oils from Cymbopogon citratus (lemongrass) leaves against Colletotrichum gloeosporioides. Leaves of the silver species Cymbopogon citratus were collected in the sub-region of the savannahs of the department of Sucre; for the extraction of essential oils (EO), fresh leaves were weighed and EO was obtained using the microwave-assisted hydrodistillation method. The antifungal activity of the EOs was evaluated using the surface seeding technique on solid medium, the activity was expressed as percentage inhibition index. Chemical characterisation of the essential oils was performed by gas chromatography coupled to mass spectrometry. The highest antifungal index efficiency of lemongrass was observed at concentrations of 5,000, 8,000 and 10,000 ppm. The main constituent identified in lemongrass EOs was citral, which is possibly related to the inhibitory activity of the fungus causing anthracnose disease in yam crop

Evaluation of the potential of Chlorella vulgaris for the removal of pollutants from standing water

In this study we evaluated the microalga Chlorella vulgaris in order to determine the ability of the microalga to remove the highest concentration of contaminants present in stagnant water. A mixing design of the microalgae with the wastewater was carried out for 20 days, with a 12:12 h photoperiod, in a greenhouse. The highest removal efficiencies for heavy metals were ≥ 98% (mainly Cd, Hg, As and Pb) and ≥ 90% for BOD5, COD, nitrates, phosphates, total phosphorus, faecal and total coliforms. Finally, according to the design analysis, it was determined that the optimal microalgae mixture 1:10 achieves the highest DO production and the highest removal, in a cultivation time of 15 days. In conclusion, microalgae demonstrate their capacity for bioremediation of rural domestic wastewater jagüeyes

Comercialización de leche cruda en sincelejo, sucre, colombia

Es bien sabido que la leche ha sido un alimento de gran importancia para el hombre desde la domesticación de los animales y el comienzo de la agricultura de pastoreo (ALAIS, 1985). Pese a esto, la leche y sus derivados pertenecen al grupo de alimentos de mayor riesgo en la salud pública, ya que sus características de composición favorecen la proliferación microbiana y por consiguiente cualquier deficiencia en sus condiciones de producción, procesamiento, manipulación, conservación, transporte y comercialización puede ocasionar trastornos en la salud de los consumidores. Se sabe desde hace muchos años, que a través de la leche se pueden transmitir enfermedades al hombre, y se han estado realizando continuos esfuerzos, tanto para erradicar las zoonosis vehiculadas por la leche, como tuberculosis y brucelosis, como para aumentar la calidad higiénica global de la leche. Se han ejecutado programas específicos para erradicar la zoonosis eliminando los agentes etiológicos de los rebaños de diversos países (LEZZACA et al., 1992; VARNAM et al., 1995)

Remediation of wastewater from the semi-artisanal tanning process using microalgal consortium

Human, commercial and industrial activities are polluting the waters that are normally used for agricultural productivity. The Ministry of the Environment (MAE) regulates these activities by demanding, according to environmental legislation, that the water collected be returned upstream in equal or better conditions than the initial ones, and within the parameters of the unified text of environmental legislation when it is discharged into the sewage system. The poor disposal of liquid effluents with the presence of chromium by various industries, especially tanneries, is causing pollution of water bodies. The percentage removal efficiency was presented 10 days after the start of the experiment, showing the highest removal for the heavy metals cadmium, arsenic and lead at 100%, followed by a reduction in the amount of total coliforms (98), faecal coliforms (100), total solids (78) and nitrates (97%). The removal of total phosphorus corresponded to 72%, while for total phosphorus it was 72%.  It is also observed that the biological oxygen demand (BOD5) was reduced by 82% and the biochemical oxygen demand (COD) by 89% with respect to the initial values found reported in tannery wastewater before the experiment. Alternately these effluents could be used as alternative substrates for the growth of microalgae, which would generate a positive impact on the total costs of biomass production at large scales

Study of endophytic bacteria isolated from commercial rice cultivation with growth promoting activity properties

In this study, the growth-promoting activity of endophytic bacteria isolated from different tissues of rice varieties from the municipality of Montería, department of Cordoba, Colombia, was evaluated in vitro. The population of endophytic bacteria was isolated on R2A agar culture medium, counted and qualitatively evaluated for nitrogen fixation, phosphate solubilization and siderophore production. Endophytic bacteria with positive activities were identified by 16S rRNA gene sequencing with 5 sets of oligonucleotides specific for the class firmicutes, beta-proteobacteria; gamma-proteobacteria; alpha-proteobacteria and actinobacteria. A total of 107 isolates of endophytic bacteria were isolated, with the highest occurrence in variety 2000 and the lowest in variety 67; the most colonized tissue was the root. Of the 22 isolates, 11 showed the ability to solubilize phosphate, 6 to produce siderophores, and 5 to fix nitrogen. Sequencing results proved the identity of Bacillus cereus and Bacillus thuringiensis, which have the ability to promote growth in rice by phosphate solubilization, nitrogen fixation and siderophore production

BOD5 AND COD REMOVAL EFFICIENCY BY Chlorella vulgaris IN WASTEWATER FROM TANNING PROCESSES

Microalgae are a very heterogeneous microbial group that provides several applications nowadays, including wastewater treatment. The treatment of wastewater is very important, as it contains pollutants that prevent its reuse. In the present study, the growth potential of the microalga Chlorella vulgaris and its purification capacity in wastewater from tanning processes were evaluated. Ch vulgaris was bioaugmented in a bioreactor, using exponential phase cells of 106 cells/mL. The Ch. vulgaris cells were treated with tanning wastewater for 20 days. BOD5 and COD parameters were measured daily. The results of the organic load degradation tests confirm that Ch. vulgaris reduces BOD5 and COD to values below those permitted by the regulations established for the leather manufacturing, tanning and dressing industry. Ch. vulgaris is able to survive the adverse conditions present in wastewater, efficiently removing pollutants present in wastewater from tanning processes

STUDY OF THE ANTIBACTERIAL ACTIVITY OF PLANT-DERIVED MEATABOLITES AGAINST PHYTOBACTERIA IN RICE CULTURE

Bacterial blast of the rice panicle, caused by the Gram-negative bacterium Burkholderia glumae, causes grain rot, generating losses of 15 to 80% of production. Although integrated management methodologies and the use of agrochemicals have been implemented to mitigate this situation, satisfactory results have not been achieved, and the excessive use of oxolinic acid has generated resistance on the part of the bacterial strains and, on the other hand, the safety of the final product for food safety worldwide. The present study aimed to implement new environmentally friendly biocontrol strategies such as the use of essential oils of Lippia alba and Lippia origanoides to reduce losses in rice crops caused by B. glumae, finding significant results of the essential oils, observing antibacterial activity of 100%, Lippia origanoides at a concentration of 90 ppm.   Lippia alba had inhibitory activity at 1550 ppm with 80% effectiveness. The chemical profiles of the essential oils showed thymol as the major secondary metabolite with an area percentage of 68% for the essential oil of L. origanoides, while L. alba contains geranial and neral in 35% and 29% respectively and are possibly associated with antibacterial activity against B. glumae and its future use for the biological management of bacterial blast in rice plants