Effect of Using Two Different Types of Carbon Nanotubes for Blackberry (Rubus adenotrichos) in Vitro Plant Rooting, Growth and Histology

Nanoparticles are able to interact with biomolecules, creating functional nanosystems for transportation within in vivo cells, and leading to the study of their potential applications in the field of plant biotechnology. Therefore, the aim of this research was to determine the growth and rooting effect of functionalized (SWCNTs-COOH) and non-functionalized nanoparticles with iron residue inner particles (SWCNTs-Fe) in blackberry (Rubus adenotrichos) in vitro plants. Two types of SWCNTs were used, both of them characterized in a solid sample through Raman spectroscopy (λ = 532 nm) showing differences in the G band between SWCNT + Fe and SWCNT + COOH. The in vitro plants (approximately 15 mm length) were inoculated in a rooting medium. Six treatments were established: 4, 8, 12 μg/ml for each type of SWCNTs and a control without nanotubes. The assessed variables consisted of the average number of days for root emergence, average number of roots per plant, average root length per plant and the average stem length. This study determined that, in general, the SWCNTs-COOH promoted the growth of the in vitro plants under this assay, when compared to the SWCNTs-Fe trials. The lowest SWCNTs-COOH dose evidenced the best results for the assessed variables. Additionally, the histological analysis also evidenced that the plants treated with SWCNTs-COOH nanotubes (4 μg/ml) increased their cellular metabolism when compared to the control group.

Analysis of Solid Waste Management and Greenhouse Gas Emissions in México: A Study Case in the Central Region

In this work, an analysis of the generation, composition and management of the urban solid waste in Mexico and its relation to greenhouse gas emissions is described;as well a case study in Morelos, a state in the central region of the country. Data were collected from the scientific literature and existing data bases at state and national levels. In addition, the emissions of greenhouse gas were calculated for a period of 14 years, using the Intergovernmental Panel on Climate Change (IPCC) methodology. The municipal solid waste data collected from 1998 to 2012 reveal an increase in the amount of waste generated in Mexico and in Morelos (38% and 43%, respectively), which have been influenced by the urbanization process and the population increase. According to the official data, the composition of the urban solid waste in Mexico, is mostly organic matter (50%), represented by food and garden residues, as well as paper and cardboard (near to 14%). While in Morelos, the percentages of generation for these materials are 44% and 9%, respectively. The management of the urban waste mainly consists of house collection, principally in metropolitan zones and medium and small cities, representing 78.7% in Mexico and 89.2% in Morelos. The second way to eliminate the solid wastes is open burning (mostly in semi-urban and rural areas), representing 14.5% and 6.7% for Mexico and Morelos, respectively. During this period, the nationwide greenhouse gas emissions derived from solid waste management (SWM) increased by 180%, while in Morelos, an increase of 42.5% was calculated. Thus, the population increment and urbanization process were correlated with the rise in the amount of residues generated in Mexico and Morelos.

Cryopreservation of Cat’s Claw (<i>Uncaria tomentosa</i>)

Uncaria tomentosa presents tomentum that resembles cat’s claws, hence its common name, is a plant that produces various secondary metabolites that are traditionally used in alternative medicine. The natural distribution of this species has been affected by indiscriminate harvesting from its habitat. In the present research, cryopreservation (liquid nitrogen, LN, -196&degC) was evaluated as an option for ex situ conservation of this species. The following techniques were evaluated: vitrification and encapsulation-dehydration of apices, vitrification of cell suspensions, and seed desiccation and vitrification. Preculture conditions and exposure times to LS and PVS2 were evaluated. Apex survival was the highest (82%) with preculture in 0.25 M sucrose followed by incubation for 20 and 30 min in LS and PVS2, respectively, prior to cooling in LN. The encapsulation-dehydration technique was evaluated by using sucrose preculture and different capsule moisture contents. Survival of apices cooled in LN was not significantly different between treatments and varied from 31.8% to 52.9% for capsule moisture contents between 22.7% and 20.3%. For cell suspensions precultured in 0.5 M sucrose, cell multiplication and formation of calli with very good appearance were observed in 61.1% of the cultures following vitrification. For cryopreservation of seeds, germination was 89.5% using the desiccation technique and 67.6% to78.1% using vitrification.

Antibacterial Activity of <i>Bougainvillea Glabra, Eucalyptus Globulus, Gnaphalium Attenuatum</i>, and Propolis Collected in Mexico

Bougainvillea glabra C., Eucalyptus globules Labill., and Gnaphalium attenuatum DC., as well as propolis, have been used in Mexican traditional medicine as a remedy to treat respiratory illnesses. There are few biological reports of such material collected in Mexico, despite the high demand for them as raw material for popular and industrial uses. The antibacterial activity of the plants and propolis studied here were evaluated against a panel of bacteria using three different methodologies: agar disc diffusion, macro and micro dilution methods. E. globules and G. attenuatum extracts showed the strongest active values (P > 0.05) in the agar disc diffusion method with a range of 8 - 22 mm inhibition zone, MIC values ranging from 25 - 250g/mL, and MBC values of 25 - 500g/mL obtained by macro and micro dilution methods. B. glabra extracts were active against E. coli, S. typhi, K. pneumoniae, S. aureus and S. agalactiae, with 8 - 13 mm inhibition zone, MICs ranging from 500 - 3000g/mL, and MBCs of 1000 - 3000g/mL. The propolis extract turned out to be active against E. coli, K. pneumoniae, S. aureus and S. agalactiae, with values of 7 - 12 mm, MICs of 1000 - 2000g/mL, and MBCs of 2000 - 2500g/mL. E. globules and G. attenuatum extracts were the most active in the three methodologies assayed. This is also the first time that the antibacterial activity of G. attenuatum has been experimentally demonstrated. The microdilution method showed to be more sensitive, less expensive and minor time-consuming technique compared with the other two.

Lima Bean(Phaseolus lunatus)Protein Hydrolysates with ACE-I Inhibitory Activity

Several protein sources can be used to produce bioactive peptides with angiotensin I-converting enzyme (ACE) inhibittory activity. Protein concentrates from ungerminated and germinated lima bean Phaseolus lunatus seed flours were hydrolyzed with Alcalase 2.4 L or pepsin-pancreatin sequential hydrolysis, and ACE inhibitory activity measured in the different hydrolysis treatments. Protein hydrolysate production was analyzed with a 23 factorial design with four replicates of the central treatment. Evaluated factors were protein concentrate source (ungerminated seeds, PC1;germinated seeds, PC2), enzyme/substrate ratio E/S (1/50 or 1/10) and hydrolysis time (0.5 or 2.0 h for Alcalase;1 or 3 h for pepsin-pancreatin). Degree of hydrolysis (DH) was high for the Alcalase hydrolysates (24.12% 58.94%), but the pepsin-pancreatin hydrolysates exhibited the highest ACE inhibitory activity (IC50 = 0.250 0.692 mg/mL). Under the tested conditions, the hydrolysates with the highest ACE inhibitory activity were produced with sequential pepsin-pancreatin using either PC1 at 1 h hydrolysis time and a 1/10 E/S ratio or PC2 at 1 h hydrolysis time and a 1/50 E/S ratio. Lima bean protein hydrolysates prepared with Alcalase or pepsin-pancreatin are a potential ingredient in the production of physiologically functional foods with antihypertensive activity.

Cryopreservation of Seeds and Embryos of Jatropha curcas L.

Jatropha curcas is a species with a variety of uses. It is grown primarily for oil for biodiesel, but also has agronomic and medicinal applications. Two methods were evaluated for cryopreservation of seeds and zygotic embryos of J. curcas: desiccation followed by rapid immersion of seeds and embryos in liquid nitrogen (LN, -196°C), and vitrification of zygotic embryos. Prior to cryo-preservation, seeds were manually scarified and the moisture content (MC) of seeds and embryos was determined. Explants were disinfected after cryopreservation. Seed germination after LN exposure was 100%. Plantlet development was better in sand substrate than that in vitro. Survival of zygotic embryos after cryopreservation was also 100%, without significant differences between treatments. Optimal development (100%) and plantlet length (51.77 mm) were observed with embryos dried for 60 min to 9.4% MC under laminar flow prior to cryopreservation. Zygotic embryos subjected to the vitrification procedure did not withstand LN exposure. Survival data for non-cryopreserved embryos after each step of the vitrification procedure provided information about embryo tolerance to cryoprotectants.

Protein engineering for natural product biosynthesis:expanding diversity for therapeutic applications

In this dispensation of the fourth industrial revolution,protein engineering has become a popular approach for increasing enzymatic activity,stability,and titer in the biosynthesis of natural products.This is attributed to its numerous advantages(over direct isolation from plants or via chemical synthesis),including decreasing or eliminating reaction byproducts,high precision,moderate handling of intricate and chemically unstable chemicals,overall reusability,and cost efficiency.Recently,protein engineering tools have advanced to redesign and enhance natural product biosynthesis.These methods include direct evolution,substrate engineering,medium engineering,enzyme engineering and immobilization,structure-assisted protein engineering,and advanced computational.Recent successes in implementing these emerging protein engineering technologies were critically discussed in this article.Also,the advantages,limitations,and applications in industrial and medical biotechnology were discussed.Last,future research directions and potential were also highlighted.