Agronomic iron-biofortification by activated hydrochars of spent coffee grounds

This work was supported by projects PY20_00585 and RDPTC-2018 (AT17_6096_OTRI UGR) from Andalusian Ministry of Economic Transformation, Knowledge, Industry and Universities and FEDER.Iron biofortification has been of main interest for tackling iron deficiency anemia, one of the highest prevalence among micronutrient deficiencies (hidden hunger) in developing countries. This study investigated the effect of activated spent coffee grounds (SCG) and its hydrochars at three temperatures (160 degrees C, 180 degrees C, 200 degrees C) as bio-chelates to level up the iron content of lettuce. Four bio-chelates (ASCG-Fe, AH160-Fe, AH180-Fe and AH200-Fe) were obtained by activation and Fe-functionalization. A pot trial was conducted at doses of 0.2% of the bio-chelates on lettuce with two controls: soil without biofortifying agents (control) and a commercial chelate (control-Fe). Outcomes showed no significant differences (p < 0.05) in soil properties nor in plant growth and morphology, indicating absence of phytotoxicity. All bio-chelates enhanced iron content of plants between 41% (AH200-Fe) and 150% (AH160-Fe) compared to control. The best biofortification effect performed by AH160-Fe was similar to control-Fe (169%), also in terms of soil-plant efficiency both products showed the same transfer factor of 0.07. A proportional impact (up to 150%) was seen on the contribution to the recommended daily intake (RDI). Moreover, higher contents of Mn (29%) and Cu (133%) was evidenced in lettuce with the application of ASCG-Fe and AH180-Fe. These findings suggest activated SCG hydrochars, better than SCG, at small (sub-toxic) doses can successfully achieve agronomic iron biofortification.Andalusian Ministry of Economic Transformation, Knowledge, Industry and Universities PY20_00585, RDPTC-2018 (AT17_6096_OTRI UGR)FEDE

Overview of the current situation relating to chemical engineering degree courses

In 2020, the Conference of Chemical Engineering Directors and Deans (CODDIQ) proposed the creation of an observatory to monitor chemical engineering degrees in Spain. This representative radiography of Chemical Engineering studies offers an initial point to observe the future changes when Royal Decree 822/2021 and proposed challenges in the last Ministerial Conference on the European Higher Education Area (EHEA) will be implanted. The survey data from CODDIQ partners allow us to know important data such as (i) the 24 international quality accreditations at Spanish universities, (ii) the high demand and the required marks, an average of 7.25, for the Chemical Engineering Bachelor’s degree, (iii) 9560 undergraduate students in this degree in Spain and their gender profile which is around 43% of women, similar than women lectures, (iv) the difficulty of this Bachelor’s degree through some indicators like duration of studies (5.25 years), graduation rate (41%) and drop-out rate (26%), (v) the employability after obtaining the Bachelor's degree is very high (>70%). In addition, Chemical engineering undergraduate and graduate students indicate their expectations are covered. In this paper, some consequences of the pandemic on students' performance (lower than before COVID-19) are analyzed, despite lectures tried to innovate in their classes and the university provided adequate tools for online teaching

A Minor Dihydropyran Apocarotenoid from Mated Cultures of Blakeslea trispora

The heterocyclic C15 apocarotenoid 1 was isolated from mated cultures of the strains F986 (+) and F921 (−) of Blakeslea trispora. This new compound formed during sexual interaction is a minor constituent of the culture media and its structure was elucidated by spectroscopic data, including 2D-NMR. A plausible biosynthetic pathway involving a double degradation of β-carotene, followed by several oxidations of the resulting monocyclofarnesane C15 fragment is proposed.This research was financed by Junta de Andalucía (Grants FQM 340, CVI 910, and P08-CVI-03901) and the Spanish Government (Grant CTQ 2010-16818, subprogram BQ)

Influence of ozonation processes on the microbial degradation of surfactants

The influence of ozonation of aqueous solutions of non-ionic surfactants was investigated in this study. The research was conducted using solutions of amine oxide based surfactants. These surfactants constitute a particular class of non-ionic surfactants that exhibit cationic behaviour in acid solution, they show good foaming properties and are skin compatible. The ozonation process was carried out at 25ºC in a stirred tank reactor for 30 min, where gaseous ozone was bubbled. The degree of mineralization achieved after the ozonation process was evaluated by measuring the total organic carbon before and after ozonation. The influence of ozonation on biodegradability of the solutions was studied using the biodegradation test by Pseudomonas putida. Biodegradation efficiency of the ozonated amine oxides based surfactants was also evaluated. It was found that the effectiveness of ozonation depended on the chemical structure of surfactant molecule. Ozonation only slightly improved biodegradation of these surfactants

Silica micro-and nanoparticles reduce the toxicity of surfactant solutions

In this work, the toxicity of hydrophilic fumed silica microand nanoparticles of various sizes (7 nm, 12 nm, and 50 μm) was evaluated using the luminescent bacteria Vibrio fischeri. In addition, the toxicity of an anionic surfactant solution (ether carboxylic acid), a nonionic surfactant solution (alkyl polyglucoside), and a binary (1:1) mixture of these solutions all containing these silica particles was evaluated. Furthermore, this work discusses the adsorption of surfactants onto particle surfaces and evaluates the effects of silica particles on the surface tension and critical micellar concentration (CMC) of these anionic and nonionic surfactants. It was determined that silica particles can be considered as non-toxic and that silica particles reduce the toxicity of surfactant solutions. Nevertheless, the toxicity reduction depends on the ionic character of the surfactants. Differences can be explained by the different adsorption behavior of surfactants onto the particle surface, which is weaker for nonionic surfactants than for anionic surfactants. Regarding the effects on surface tension, it was found that silica particles increased the surface activity of anionic surfactants and considerably reduced their CMC, whereas in the case of nonionic surfactants, the effects were reversed

A SpiNNaker Application: Design, Implementation and Validation of SCPGs

In this paper, we present the numerical results of the implementation of a Spiking Central Pattern Generator (SCPG) on a SpiNNaker board. The SCPG is a network of current-based leaky integrateand- fire (LIF) neurons, which generates periodic spike trains that correspond to different locomotion gaits (i.e. walk, trot, run). To generate such patterns, the SCPG has been configured with different topologies, and its parameters have been experimentally estimated. To validate our designs, we have implemented them on the SpiNNaker board using PyNN and we have embedded it on a hexapod robot. The system includes a Dynamic Vision Sensor system able to command a pattern to the robot depending on the frequency of the events fired. The more activity the DVS produces, the faster that the pattern that is commanded will be.Ministerio de Economía y Competitividad TEC2016-77785-

Hydrochars Derived from Spent Coffee Grounds as Zn Bio-Chelates for Agronomic Biofortification

Previous studies have attributed both phytotoxicity and the capacity to mobilize nutrient elements to the presence of polyphenols and melanoidins in spent coffee grounds (SCG) and SCG-hydrochars obtained through hydrothermal carbonization (HTC). This work aimed to evaluate SCG and two SCG-hydrochars obtained at 160 and 200 °C that were functionalized with Zn salts (bio-chelates), to achieve the in vitro biofortification of lettuce. Two application modes were established: (1) a fixed Zn concentration of 10 mg kg−1 of soil and (2) a fixed dose of 0.5% bio-product. Soil alone (control A) and commercial chelates (control B) were used as controls. Outcomes showed that SCG-hydrochars retain the capacity to mobilize Zn compared to SCG. However, the chelating capacity was reduced (Zn: 94%) and the toxicity was significantly increased (p < 0.05) with higher temperatures of HTC (200 °C). Both fresh and dry lettuce weights were less affected at doses of 0.5% of bio-product and registered a maximum increase of 136% of Zn in the plant content. The present study approaches the possibility of using these by-products as bioinorganic fertilizers at subtoxic doses, although more research is neededPY20_00585 from FEDER and RDPTC-2018 (AT17_6096_OTRI UGR) from the Andalusia n Ministry of Economic Transformation, Knowledge, Industry and Universities

Why Should We Be Concerned with the Use of Spent Coffee Grounds as an Organic Amendment of Soils? A Narrative Review

Spent coffee grounds (SCG) are produced in massive amounts throughout the world as a bio-residue from coffee brewing. However, SCG are rich in carbohydrates, proteins, lipids, bioactive compounds and melanoidins, which are macromolecules with chelating properties. Additionally, SCG have showed potential applications in several fields such as biotechnology (bioethanol, volatile aromatic compounds, carotenoids, fungi and enzymes), energy production (combustion, pyrolysis, torrefaction, gasification, hydrothermal carbonization) and environmental sciences (composting). This review will focus on the last of these applications. SCG improve soil quality by increasing their chemical, physicochemical, physical properties and biological fertility. However, SCG inhibit plant growth at very low concentrations (1%) due to i. the stimulation of microbial growth and consequent competition for soil nitrogen between soil microorganisms and plant roots; ii. the presence of phytotoxic compounds in SCG, such as polyphenols. The SCG transformations that have proven to eliminate these compounds are vermicomposting and pyrolysis at 400 degrees C. However, it has been pointed out by some studies that these compounds are responsible for the chelating properties of SCG, which makes their elimination not recommended. The use of SCG as biochelates has also been studied, generating a residue-micronutrient mixture for the biofortification of edible plants.Andalusian Ministry of Economic Transformation, Knowledge Industry and Universities PY20_00585Plan Propio de Investigacion y Transferencia of the University of Granada under the program "Intensificacion de la Investigacion, modalidad B

Spent coffee grounds as feedstock for the production of biosurfactants and the improved recovery of melanoidins

Spent coffee grounds (SCG) are wastes generated in high amounts worldwide. Their composition makes them a promising feedstock for biotechnological processes. Here we show that the production of the biosurfactant surfactin by submerged culture of a Bacillus subtilis strain growing on SCG is possible, reaching concentrations up to 8.8 mg/L when using SCG at 8.3 g/L in the medium. In addition, we report a synergy between the production of surfactin and the recovery of melanoidins, an added-value compound already present in SCG. More specifically, the concentration of melanoidins in the culture medium increased between 2.1 and 2.5 times thanks to the presence of the B. subtilis in the culture. Furthermore, we have observed a strong interaction between surfactin and melanoidin aggregates through dynamic light scattering measurements, and that both of them can be co-purified with an acid precipitation. We have also characterized the interfacial and antioxidant properties of the cell-free supernatant and surfactin extract, as well as the distribution of the congeners of the biosurfactant. Altogether, this work describes a promising approach to obtain biosurfactants and antioxidant molecules in a single operation, which can be used to design several new formulations of interest for bioremediation, amendment of soils, food and cosmetics

Efecto de la densidad de población y la fertilización sobre la productividad del agua y rendimientos de híbridos de maíz en el Valle de México

La insuficiencia alimentaria en maíz, la crisis de agua y fertilizantes a nivel mundial, demandan incrementar la eficiencia en el uso de recursos incrementando o conservando la producción. El objetivo del trabajo fue definir la respuesta de cuatro híbridos de maíz blanco (Tlaoli Puma, Atziri Puma, H-49 AE y H-47 AE) en dos ambientes con dos densidades de población y dos dosis de fertilización y testigo sin fertilizar. Como arreglo factorial, en los ambientes Cuautitlán (FESC-UNAM) y Texcoco (CEVAMEX), Estado de México, se evaluaron los híbridos con dos densidades de siembra (D1=75 000; D2=90 000 plantas ha-1) y tres tratamientos de fertilización (F1=160-80-00, F2=120-40-00, F3=00-00-00). El experimento en bloques completos al azar se conformó con los tratamientos y la combinación de los factores 2×4×2×3 establecidos en tres repeticiones. Las medias se compararon con el método Tukey (P < 0.05). Para el rendimiento de grano y productividad del agua, en la FESC-UNAM con menor agua total, resultaron de 5.96 Mg ha-1 y 1.29 kg m-3 en CEVAMEX 4.76 Mg ha-1 y 0.5 kg m-3; el híbrido Atziri Puma sobresalió con 6.52 Mg ha-1 y 1.09 kg m-3. No se observó efecto significativo de la densidad de siembra y D1 resultó con 5.32 Mg ha-1 y 0.9 kg m-3 contra D2 con 5.4 Mg ha-1 y 0.9 kg m-3. En la fertilización, F1 fue superior estadísticamente con 5.64 Mg ha-1 y 0.94 kg m-3, pero no hubo diferencia entre F2 (5.24 Mg ha-1 y 0.88 kg m-3) y el control F3 (5.19 Mg ha-1 y 0.87 kg m-3). Se presentó interacción de los ambientes con los híbridos y destacó el híbrido Atziri Puma en la FESC-UNAM (7.3 Mg ha-1 y 1.58 kg m-3). El sitio FESC-UNAM tiene potencial productivo en condiciones de temporal con los híbridos Puma e INIFAP