BIODIVERSIDAD DE LA CUENCA MEDIA Y BAJA DEL RÍO CUNAS

La investigación se realizó en la cuenca media y baja del río Cunas, de abril de 2010 a marzo de 2011, con el objetivo de evaluar el estado actual de la biodiversidad de las comunidades vegetales y del ecosistema acuático, mediante indicadores de estructura y diversidad. El muestreo de la flora terrestre se realizó mediante los métodos de las líneas de Canfield y el de área. La evaluación de la diversidad vegetal, se realizó en base a la estructura y diversidad de las comunidades vegetales. La estructura, se determinó mediante el índice de valor de importancia y la diversidad, mediante los índices de riqueza de especies, de Simpson y de Shannon Wiener. Los resultados indican que las especies que presentan el mas alto índice de valor de importancia son Agave americana, Eucaliptus globulus y Baccharis sp, con valores de 99,63%, 58,06% y 49,7%, respectivamente, mientras que las especies que presentan el mas bajo índice de valor de importancia, son Cassia sp, Opuntia ficus indica y Alnus jurullensis con valores de 8,16%, 7,69% y ,73%, respectivamente. El índice de riqueza de especies (S = 10), indica que en la zona de estudio existen 10 especies vegetales. El índice de Simpson (λ = 0,25148), indica una probabilidad de 0,25148 de que si tomamos dos individuos al azar de una muestra, sean de la misma especie. El índice de Shannon Wiener (H ´= 0,3085), indica que el grado promedio de incertidumbre en predecir a que especie pertenecerá un individuo escogido al azar de una colección es de 0,3085. Las comunidades biológicas presentes en el ecosistema acuático, estuvieron conformadas por plancton, bentos, necton y vegetación acuática. Concluyéndose que la diversidad de la flora terrestre y de la flora y fauna acuática en la cuenca media y baja del río Cunas, presenta cierto grado de alteración, debido a las diferentes actividades antropogénicas desarrolladas en el área de influencia.

Spray-Drying Microencapsulation of Pink Guava (Psidium guajava) Carotenoids Using Mucilage from Opuntia ficus-indica Cladodes and Aloe Vera Leaves as Encapsulating Materials

In this work, the capacity of the mucilage extracted from the cladodes of Opuntia ficus-indica (OFI) and aloe vera (AV) leaves as wall material in the microencapsulation of pink guava carotenoids using spray-drying was studied. The stability of the encapsulated carotenoids was quantified using UV–vis and HPLC/MS techniques. Likewise, the antioxidant activity (TEAC), color (CIELab), structural (FTIR) and microstructural (SEM and particle size) properties, as well as the total dietary content, of both types of mucilage microcapsules were determined. Our results show that the use of AV mucilage, compared to OFI mucilage, increased both the retention of β-carotene and the antioxidant capacity of the carotenoid microcapsules by around 14%, as well as the total carotenoid content (TCC) by around 26%, and also favors the formation of spherical-type particles (Ø ≅ 26 µm) without the apparent damage of a more uniform size and with an attractive red-yellow hue. This type of microcapsules is proposed as a convenient alternative means to incorporate guava carotenoids, a natural colorant with a high antioxidant capacity, and dietary fiber content in the manufacture of functional products, which is a topic of interest for the food, pharmaceutical, and cosmetic industries.

Keratinase Production by Endophytic Bacteria Aneurinibacillus aneurinilyticus VRCS-4 Isolated from Xerophytic Plant Opuntia ficus - indica (Prickly pear)

Bacterial endophytes colonize an ecological niche which is unexplored site makes them suitable to produce pharmacologically active substances with vast biotechnological potential therefore, xerophytes were chosen to isolate the endophytes. In the present study forty endophytic bacterial isolates were isolated from xerophytic plants grown near poultry farms and feather dumping sites. Of them eight isolates showed zone of hydrolysis and the maximum zone of hydrolyisis of 36mm was with VRCS-4 on skimmed milk agar. This isolate exhibited efficient feather degradation and was identified as Aneurinibacillus aneurinilyticus based on its morphological, biochemical test and molecular sequencing method. The isolate was deposited in NCBI with an accession number MW227423.The isolate showed maximum en-zyme activity of 140.24U/ml at 72h, pH 7.5 and 40º C at 140 rpm. Chicken feather 1% (w/v) used as a sole source of carbon and nitrogen. Feather deg-radation by A.aneurinilyticus VRCS-4 showed 90% degradation in feather meal broth. Ours appears to be the first report on keratinase production by endophytic bacteria from xerophytic plant (Opuntia ficus -indica).

Estudio de los parámetros cinéticos en el secado de la cáscara de tuna (Opuntia ficus indica)

El secado incluye dos procesos fundamentales un proceso de transferencia de calor que permite la evaporación del líquido, y la transferencia de masa que permite la difusión del líquido del alimento. El objetivo consiste en determinar los parámetros cinéticos del secado en la cáscara de tuna mediante una estufa a las temperaturas de 50°C, 65°C y 80°C. La cáscara de tuna fue sometida en una estufa Mermmert para un secado por convección a temperaturas de 50°C, 65°C y 80°C en tiempo de 0 a 340 minutos, las cáscaras de tuna trozadas de 2cm x 2cm con espesor de 0.05cm acondicionados en placas petri. Los valores de difusividad fueron de 4.000x10-5m2/s, 5.300x10-5 m2/s, 4.000x10-5 m2/s a las temperaturas de 50°C, 65°C y 80°C respectivamente obteniendo una energía de activación E= 19.419 KJ/mol para un valor de R2=0.994.

Polysaccharide Based Polymers Produced by Scabby Cankered Cactus Pear (Opuntia ficus-indica L.) Infected by Neofusicoccum batangarum: Composition, Structure, and Chemico-Physical Properties

Neofusiccocum batangarum is the causal agent of scabby canker of cactus pear (Opuntia ficus-indica L.). The symptoms of this disease are characterized by crusty, perennial cankers, with a leathery, brown halo. Characteristically, a viscous polysaccharide exudate, caking on contact with air, leaks from cankers and forms strips or cerebriform masses on the surface of cactus pear cladodes. When this polysaccharide mass was partial purified, surprisingly, generated a gel. The TLC analysis and the HPLC profile of methyl 2-(polyhydroxyalkyl)-3-(o-tolylthiocarbomoyl)-thiazolidine-4R-carboxylates obtained from the mixture of monosaccharides produced by acid hydrolysis of the three EPSs examined in this research work [the polysaccharide component of the exudate (EPSC) and the EPSs extracted from asymptomatic (EPSH) and symptomatic (EPSD) cladodes] showed the presence of d-galactose, l-rhamnose, and d-glucose in a 1:1:0.5 ratio in EPSC while d-galactose, l-rhamnose, d-glucose, and d-xylose at the same ratio were observed in EPSH and EPSD. The presence of uronic acid residues in EPSC was also showed by solid state NMR and IR investigation. Furthermore, this manuscript reports the chemical-physical characterization of the gel produced by the infected cactus pear.

Indicaxanthin from Opuntia ficus-indica Fruit Ameliorates Glucose Dysmetabolism and Counteracts Insulin Resistance in High-Fat-Diet-Fed Mice

Obesity-related dysmetabolic conditions are amongst the most common causes of death globally. Indicaxanthin, a bioavailable betalain pigment from Opuntia ficus-indica fruit, has been demonstrated to modulate redox-dependent signalling pathways, exerting significant anti-oxidative and anti-inflammatory effects in vitro and in vivo. In light of the strict interconnections between inflammation, oxidative stress and insulin resistance (IR), a nutritionally relevant dose of indicaxanthin has been evaluated in a high-fat diet (HFD) model of obesity-related IR. To this end, biochemical and histological analysis, oxidative stress and inflammation evaluations in liver and adipose tissue were carried out. Our results showed that indicaxanthin treatment significantly reduced body weight, daily food intake and visceral fat mass. Moreover, indicaxanthin administration induced remarkable, beneficial effects on HFD-induced glucose dysmetabolism, reducing fasting glycaemia and insulinaemia, improving glucose and insulin tolerance and restoring the HOMA index to physiological values. These effects were associated with a reduction in hepatic and adipose tissue oxidative stress and inflammation. A decrease in RONS, malondialdehyde and NO levels, in TNF-α, CCL-2 and F4-80 gene expression, in p65, p-JNK, COX-2 and i-NOS protein levels, in crown-like structures and hepatic inflammatory foci was, indeed, observed. The current findings encourage further clinical studies to confirm the effectiveness of indicaxanthin to prevent and treat obesity-related dysmetabolic conditions.