Removal of Azo Dyes from Water Using Natural Luffa cylindrica as a Non-Conventional Adsorbent.

Reducing high concentrations of pollutants such as heavy metals, pesticides, drugs, and dyes from water is an emerging necessity. We evaluated the use of Luffa cylindrica (Lc) as a natural non-conventional adsorbent to remove azo dye mixture (ADM) from water. The capacity of Lc at three different doses (2.5, 5.0, and 10.0 g/L) was evaluated using three concentrations of azo dyes (0.125, 0.250, and 0.500 g/L). The removal percent (R%), maximum adsorption capacity (Qm), isotherm and kinetics adsorption models, and pH influence were evaluated, and Fourier-transform infrared spectroscopy and scanning electron microscopy were performed. The maximum R% was 70.8% for 10.0 g L-1Lc and 0.125 g L-1 ADM. The Qm of Lc was 161.29 mg g-1. Adsorption by Lc obeys a Langmuir isotherm and occurs through the pseudo-second-order kinetic model. Statistical analysis showed that the adsorbent dose, the azo dye concentration, and contact time significantly influenced R% and the adsorption capacity. These findings indicate that Lc could be used as a natural non-conventional adsorbent to reduce ADM in water, and it has a potential application in the pretreatment of wastewaters.

Properties of Luffa Cylindrica Mats Reinforced Castor Oil-Based Polyurethane Composite as an Alternative for Oriented Strand Board.

The main objective of this work was to produce and characterize a novel ecofriendly castor oil-based polyurethane (COPU) matrix composite reinforced by Luffa cylindrica mats, luffa for short, to be used as panels, as an alternative to oriented strand board (OSB). To do so, the mechanical behavior was evaluated by tree point flexural, perpendicular o surface tensile, screw pullout, and impact tests that were carried on the novel composite along with the neat matrix. Furthermore, the physical characteristics, the thermomechanical behavior, and the functional groups of the materials were observed by water absorption and thickness swelling tests along with dilatometry and Fourier transform infrared spectroscopy (FTIR). A comparison with commercialized OSB was also performed for control. The luffa/COPU composite was prepared by hand lay-up with 48 vol% of luffa mats incorporated as the maximum allowed by the mold under the available resources for manufacturing. The luffa fibers acted as a good reinforcement for the COPU matrix, where the flexural strength and modulus of elasticity were increased by more than 23 and 10 times, respectively, and the other mechanical properties more than doubled for the composites compared to the neat COPU resin. In general, the composite presented a lower performance compared to the commercial OSB, with the impact results being the exception. The water absorption and thickness swallowing results showed an already-expected behavior for the studied materials, where the better performance was found for the hydrophobic neat resin. The FTIR revealed that there was little interaction between luffa and COPU resin, which can be translated to a weak interface between these materials. However, the mechanical behavior, together with the other results presented by the luffa/COPU composite, confirm it is more than enough to be used as civil construction panels such as OSB.

Development of a biosponge based on Luffa cylindrica and crosslinked chitosan for Allura red AC adsorption.

A new bioadsorbent from Luffa cylindrica and cross-linked chitosan was proposed in the present study. Luffa was used as a natural support medium for chitosan crosslinked with glutaraldehyde (LCsG) and epichlorohydrin (LCsE). Biosponges were applied to remove Allura red from aqueous solutions. LCsG and LCsE were produced using different concentrations of chitosan (1%, 3% and 5% (m v-1)) and crosslinking agents (0.5%, 1.0% and 1.5% (v v-1)). Based on the FT-IR spectra, functional groups characteristic of chitosan crosslinked with glutaraldehyde and epichlorohydrin confirmed the crosslinking. In addition, the biosorbent revealed highly efficient functional groups and morphology with irregularities favorable for adsorption. It was found that the increase in the percentage of glutaraldehyde and epichlorohydrin increased the sample's swelling degree, and the degree of cross-linking was greater than 80% for all LCsG. The results regarding the degree of swelling and degree of crosslinking corroborated with the evaluation of the biosponge's adsorptive potential. The Sips model predicted the equilibrium isotherms, with a maximum adsorption capacity of 89.05 mg g-1 for LCsG and 60.91 mg g-1 for LCsE. The new procedure was successful. Luffa was excellent support for chitosan, resulting in an attractive, low-cost bioadsorbent, preventing renewable sources.

Stability of immobilized laccase on Luffa Cylindrica fibers and assessment of synthetic hormone degradation.

In this work were studied the pH, thermal, and storage stability of free and immobilized laccases. Enzymes were produced by Pleurotus ostreatus on potato dextrose (PD) broth and potato dextrose modified (PDM) broth, and immobilized using Luffa cylindrica fibers as support. Both free and immobilized enzymes were assessed on their respective enzymatic activities and for 17α-ethinylestradiol (EE2) degradation. The optimum pH conditions concerning laccase activity ranged from 3.6 to 4.6, while temperature ranged between 30 °C and 50 °C for both free and immobilized enzyme. Laccase produced using PD broth presented greater storage stability and thermal stability than that of PDM. Best EE2 removals were of 79.22% and 75.00% for the free and immobilized enzymes, respectively. Removal rates were assessed during 8 h at pH 5. The removal of 17α-ethinylestradiol was stabilized in the fourth cycle of use. Results imply that immobilization promoted stability towards pH and temperature variations, although media played a decisive role in the enzymatic activity. Both free and immobilized laccases of P. ostreatus were able to degrade EE2, whereas immobilized laccase in PDM medium presented possible reuse applicability, albeit removal was not optimal when compared to other reports.

Caso de intoxicación en Venezuela, por el uso de la planta de Estropajo o Tusa (Luffa cylíndrica ) / Case of intoxication by the use of the loofah sponge or tusa (Luffa cylindrica) in Venezuela

En algunas regiones del mundo, las plantas originan importantes problemas clínicos, causando gran morbilidad y mortalidad, principalmente después de la intoxicación no intencional. Este trabajo tiene como objetivo principal describir un caso clínico presentado en el Servicio de Toxicología Médica, Hospital “Doctor Leopoldo Manrique Terrero”, Caracas, Venezuela (2012), de una intoxicación con la planta de estropajo (Luffa  cylindrica), perteneciente a la familia de las Cucurbitáceas, usada inadecuadamente como instilación nasal. El análisis clínico otorrinolaringológico permitió evidenciar un cuadro agudo, grave con obstrucción de vías aéreas superiores, producido por el uso tópico de extracto de la planta de estropajo (Luffa  cylindrica), como medicamento nasal para tratar una sinusitis crónica. El paciente presentó 2 horas después de la instilación,  una disfonía,  con un intenso edema de úvula; se encontraba confundido, con cefalea, así como acentuada odinofagia y dificultad respiratoria. Tras la revisión de la literatura se permite plantear que se trata del primer caso referido o publicado de esta inusual intoxicación y daño de vías aéreas superiores ocasionado por esta planta. El paciente fue tratado con oxígeno (SOS), hidrocortisona y clorfeniramina recuperándose después de 48 h de tratamiento sintomático.

In some world regions, plants originate important clinical problems, causing significant morbidity and mortality, mainly after unintentional poisoning. This paper aims to describe a case seen at the Medical Toxicology Service, "Dr. Leopoldo Manrique Terrero " Hospital, Caracas, Venezuela (2012), which was a loofah plant poisoning (Luffa cylindrica), belonging to Cucurbitaceae family, used inappropriately as nasal instillation. The otorhinolaryngology clinical analysis demonstrated an acute, severe upper airway obstruction produced by the topical use of loofah (Luffa cylindrica) plant extract as nasal medication to treat chronic sinusitis. The patient developed 2 hours after instillation, a dysphonia, with intense uvula edema, confusion, headache and sore throat and accentuated respiratory distress. After literature review it is suggested that this is the first referred or published case in this unusual intoxication and upper airway damage caused by this plant. The patient was treated with oxygen (SOS), hydrocortisone and chlorpheniramine recovering after 48 h of symptomatic treatment.

Eficacia del cepillo de esponja vegetal (Luffa cylindrica. L Roem) en la remoción de placa supragingival. Paraguay, 2010 / Effectiveness of the loofa (Luffa cylindrica. L Roem) brush in the supragingival plaque removal. Paraguay, 2010

Una de las causas principales de las dolencias bucales es la placa dental. Para el control de la misma, el cepillo con esponja vegetal (Luffa cylindrica. L Roem) podría convertirse en un auxiliar alternativo económico. El objetivo de este estudio fue determinar la eficacia del cepillo de esponja vegetal frente al cepillo convencional en la remoción de placa supragingival. Ensayo clínico, aleatorizado y simple ciego para el evaluador. Fueron incluidos en el estudio 95 estudiantes de Odontología de las Universidades del Pacífico Privada, Nacional de Asunción, Central del Paraguay y Autónoma de Asunción sin patología bucal evidente, con más de 20% de placa dental en el examen inicial. La presencia de placa gingival basal fue evaluada con el índice de O' Leary tras seis horas mínimas sin cepillado ni uso de colutorios, a continuación se procedió al cepillado con los métodos asignados volviéndose a evaluar la presencia de placa supragingival. No se observó diferencia significativa en el porcentaje promedio de placa por la técnica Luffa en comparación con la técnica convencional después del cepillado (60% ±19 vs 62% ± 21 valor de p = 0,53, prueba t de student. El cepillo con esponja vegetal (Luffa cylindrica. L Roem) es una alternativa económica para la reducción de la placa supragingival.

One of the main causes of oral diseases is dental plaque. The loofah (Luffa cylindrica. L Roem) brush could become an economics alternative auxiliary to control dental plaque. The objective of this study was to determine the effectiveness of the loofa brush against the conventional toothbrush in the supragingival plaque removal. This was a randomized clinical trial, single blinded for the evaluator. Ninety five odontology students from the governmental National University of Asuncion and the private Pacifico and Autonoma de Asunción universities were included in the study. They did not have any obvious oral pathology and had more than 20% of dental plaque in the initial examination. The presence of basal gingival plaque was evaluated with the O’ Leary index after a minimum of six hours without brushing and using mouthwash. Then, they brushed their teeth with the method assigned and the presence of supragingival plaque was reevaluated. There was no significant difference in the mean percentages of plaque by the Luffa plaque technique compared with the conventional technique after brushing (60% ± 19 vs 62% ± 19 vs 62 ±, p value=0.53, Student’s t test). The loofa brush (Loofah cylindrica, L. Roem) is an economical alternative for the reduction of the supragingival plaque.

Phytochemical and antimicrobial investigation of Luffa cylindrica / Investigacion fitoquimica y antimicrobiana de Luffa cylindrica

3-hydroxy-1-methylene-2,3,4,4-tetrahydroxynapthalene-2-carbaldehyde (1), 22,23-dihydroxy spinasterol (2) were isolated from petroleum ether extrct of the fruits of Luffa cylindrical. The structures of the isolated compounds were elucidated by extensive spectroscopic studies including IR and high field NMR analysis.Petroleum ether extract (i.e. crude extract) exhibited mild to moderate antimicrobial activity. This is the first report of isolation of compound of 1 – 2 from this species.

3-hydroxi-1-metilen-2,3,4,4-tetrahidroxinaftalen-2-carbaldehido (1), 22,23-dihidroxispinasterol (2) fueron aislados de un extracto en eter de petróleo de la fruta de Luffa cylindrica. Las estructuras de estos compuestos fueron deducidas por estudios espectroscópicos incluyendo IR y RMN de alto campo. El extracto crudo en éter de petróleo mostró actividad antimicrobiana de leve a moderada. El presente estudio representa el primer reporte de estos compuestos en L cylindrica.