Biology and Life Sciences Forum

Biotechnology is essential for developing profitable and productive techniques to obtain metabolites. Two technologies can be used: solid or liquid fermentation and enzymatic treatments. In this context, the objective of this work was to evaluate the use of rice husk, a lignocellulosic material, to obtain bioactive compounds by lignin oxidative transformation and demethoxylation, respectively, through enzymatic treatments of P. chrysosporium and G. trabeum. In the first step, solid fermentation was used to obtain the enzyme Lig. Peroxidase and methoxyl hydrolase were quantified as 80 UE and 50 UE, respectively. This enzyme concentrate was lyophilized and used to prepare an enzymatic consortium (240 UE LigP and 150 UE metH) applied in the second phase of enzymatic treatment. The overall process involved 20 days in the solid fermentation step and 2 h for the enzymatic treatment. The obtained products were characterized by having veratryl alcohol and veratryl aldehyde at contents of 70.4 ± 0.1 and 23.3 ± 0.3 mg/g, respectively. Moreover, the analyzed products did not show cytotoxicity but revealed antioxidant and bacteriostatic activities. No anti-inflammatory activity was detected. In the context of circular economy, the obtained results pointed out the use of combined solid fermentation and enzymatic treatment as a viable strategy to valorize rice husk. The applications of these bioactive compounds presenting bactericidal and bacteriostatic activity and not showing toxicity are very common in medicine, agriculture, and environmental health, among others, and can be incorporated both in free systems and immobilized in spheres, capsules or biopolymer films, which is an important input for obtaining functionalized materials that are in high demand today. Full article

It is undeniable that suitable packaging will extend the shelf life of the food. The packaging industry has had to renew and innovate in a world where consumers are increasingly environmentally conscious in order to deal with the impact of the production of petroleum-derived plastics and the management of the waste generated by them. In this way, the use of biopolymers has been proposed, mainly those produced from renewable sources and with biodegradability and/or compostability properties. However, these types of materials are more expensive and do not have the same performance as petroleum-derived materials. Besides, the technologies for film preparation are not adapted for these materials. Therefore, new technologies must be studied and implemented to make the packaging industry a sustainable industry. Recently, non-solvent phase inversion (NIPS) and electrospinning techniques, which are widely used for membrane fabrication, have been proposed for the fabrication of films for food packaging applications from biopolymers and green solvents. Full article

The objective of this work was to formulate PVA films with the addition of modified phenols, chitosan, silver, or copper nanoparticles with fungistatic and bacteriostatic activity. The films were characterized by Fourier transform infrared spectroscopy, thermogravimetry analysis, differential scanning calorimetry, and scanning electron microscopy. The bacteriostatic activity against Salmonella gallinarum and Lactobacillus acidophilus, and the fungistatic activity against Penicillium acidophilus were determined. The results indicated that the addition of phenols enhanced the effect on the stability of the chemical structure of the PVA film. PVA films with modified bioactives and nanoparticles inhibited the colonization of the microorganisms tested, indicating germicidal control. Full article

A study of materials for wind turbine blades with nanotechnology—from the energy point of view—is an essential topic because resources and fossil fuels are running out. Human beings need to create alternative energies, including wind energy. This research aims to improve the mechanical properties of epoxy resin wind turbine blades by incorporating nanocelluloses obtained from pineapple residues. To determine the quality of the nanobiocomposites, materials with different epoxy resin–nanocellulose ratios were prepared. The mechanical properties of tension, compression, and bending were evaluated, and hardness tests of the material were conducted. The results indicated a general improvement in all the mechanical properties considered over the material without the nanocellulose. Full article

In the context of the so-called lignocellulose bio-refinery, the coconut shell (S) and pulp (P) of Acrocomia aculeata (Arecaceae) are interesting agro-industrial wastes that can be used as feedstock for the production of high value-added products. The aim of this work was to evaluate these lignocellulosic residues S and P, to obtain the microcrystal (MCC) and microfiber (MFC) of cellulose, and to characterize them to propose possible applications. First, cellulose content in the raw materials was determined, being 39.69% and 45.42% for both (S and P)) respectively, respectively. Then, the purification of residues was carried out via alkaline and bleaching treatments. Next, in order to obtain MCC and MFC from the purified cellulose, a chemical treatment with HCl (for MCC) and a mechanical treatment with a blender (for MFC) were performed. The size and morphology were observed via MEB, and properties were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential thermogravimetric analysis (DTG). Full article

Phenolic compounds from propolis extract (PE) have antioxidant and antimicrobial properties; however, extracts from this raw material are not water soluble. This study aimed to stabilize the phenolic compounds from green propolis extract in cassava and potato starch nanoparticles produced by the anti-solvent precipitation method. The obtained materials displayed a crystalline structure related to starch nanomaterials with a V_6h-type crystalline structure. The starch nanoparticles interacted with the phenolic compounds by means of hydrogen bonds and increased the hydrophobicity in the nanomaterials. The developed starch nanomaterials loaded with the phenolic compounds from PE could be potentially used as a novel ingredient in food packaging. Full article

Broccoli is a highly perishable vegetable with unique nutritional characteristics. Modified atmosphere packaging (MAP) has proven to be a successful technology to extend broccoli shelf-life. The main disadvantage of MAP is the extensive use of petrochemical-based films resulting in huge quantities of domestic plastic waste. In this study, suitability of a biodegradable cellulose-based film for broccoli florets packaging was evaluated, as an alternative to polypropylene film. Florets packaged in cellulose-based film showed a high mass loss and extremely low in-package O₂ concentrations, which made this material unsuitable for broccoli packaging application. Improved gas and water vapor barrier properties should be considered for biodegradable packages, in order to make their application for vegetable packaging feasible. Full article

Thermoplastic starch films (TPS) are an alternative for single-use plastics in packaging. Evaluating large-scale production alternatives that maintain the properties of these bio-based polymers is a crucial factor in understanding their potential industrial use. This preliminary study focuses on testing whether a mathematical model used to predict the drying conditions of ceramic film via tape casting can be adapted to the production of TPS. It also determines the possible drying tape speeds for this type of polymeric film. Full article

Pectin is a polysaccharide that is known for its gelling properties and its applications in the pharmaceutical industry. This can be divided into two structural groups, high methoxyl pectins (HMP) and low methoxyl pectins (LMP). Currently, there is little information on the properties of the orange pectin in which LPM predominates. The aim of this study was therefore to investigate the mechanical properties of gels produced with pectin isolated from orange peels. The results showed similar values to those found in the literature, except for hardness. The gels produced from the pectin could be used in the industry, the formulation varying depending on the application. Full article

This work presents a review related to the obtainment of cellulose from different structures in agro-industrial residues, both for application in the food industry and for the reinforcement of other materials. Cellulose nanofibers are produced by the heart of palm (Bactris gasipaes) industry in Brazil and are used as a stabilizer in avocado oil emulsions; conversely, cellulose nanocrystals are produced in waste from the tequila industry (Agave tequilana Weber var. Azul) in Jalisco, Mexico, and are used for reinforcement applications. Full article

Lactic acid is a compound used industrially due to its properties. There are two methods for its production: chemical synthesis and microbial fermentation. In microbial fermentation, food industry waste can be used as a substrate, providing a route towards achieving a circular economy. Thus, this study evaluated different substrates for Lactobacillus plantarum growth, a lactic acid producer, such as molasses, whey, glucose, and saccharose, either alone or supplemented with additional nutrients. Bacterial growth parameters were assessed using OD₆₂₀ measurement. It was shown that whey supplemented with yeast extract supported the best growth, allowing a μ_max = 0.63 h⁻¹. Full article

Livestock manure management, especially related to soil-fertilisation practice, is responsible for most of the emissions in agriculture, and in particular the ammonia emissions (NH₃), which play a key role in environmental problems, affecting water, soil and air quality. Within the digital agricultural framework, EO data contribute to agricultural-practices monitoring such as manure spreading, to mitigate pollutant emissions. This study presents a GIS-based tool on an open-source platform, developed for susceptibility estimation of sewage spreading occurrence in agricultural areas of Italy. The tool is based on the analysis of multispectral and hyperspectral satellite time series in synergy with field data and ancillary information collected from regional repositories, to produce a series of classified and prioritised spatially explicit information. Spectral analysis of satellite acquisitions enabled the identification of manure spreading with the precision of about 83%. Field campaigns from October to March were carried out to validate the spreading event. The case study demonstrates the ability of the proposed GIS-based tool in supporting the monitoring of manure spreading. Full article

Detecting N-deficiency early in a plant’s development before visual symptoms become pronounced and irreparable damage is done is crucial to maintaining optimum grain yield and biomass production. Chlorophyll fluorescence technology (CFT) is a quick, non-invasive, non-destructive, and informative technique that is used to study the physiological status of plants at any given stage of development. The objective of the study was to determine the photosynthetic and growth responses of N-deficient maize seedlings. Two N treatments, 10 t/ha N and 50 t/ha N, were evaluated in a greenhouse in a completely randomized design with 12 replications. The results showed a significantly (p < 0.05) higher CO₂ assimilation rate, maximum quantum yield of PSII photochemistry, effective quantum yield of PSII photochemistry, and chlorophyll concentration in plants that received 50 t/ha N compared to plants on 10 t/ha N at 3 and 4 weeks after fertilizer application (WAFA). In contrast, plants on 10 t/ha showed a higher level of non-photochemical stress due to up-regulation of nitric oxide production in PSII [Y(NO)] than plants on 50 t/ha. Non-photochemical quenching due to down-regulation of nitric oxide production in PSII [Y(NPQ)] was comparable (p > 0.05) in both treatments. There was no significant difference in plant height, although wider stem girth was recorded in plants on 50 t/ha. The significantly higher levels of Y(NO) in plants on 10 t/ha N suggest an alteration in nitrogen metabolism and increased production of reactive nitrogen species which may potentially cause cellular damage if not diagnosed early and managed adequately. Full article

Citrus tristeza virus (CTV) is one of the most destructive diseases affecting citrus and is a major cause of reductions in citrus yield. CTV epidemics have caused the death of millions of citrus trees globally. The present study aims to evaluate citrus cultivars against CTV and its vector (aphid) population. The highest levels of infection and vector population were recorded in Mangal Singh, whereas the lowest were found in the early fruiter (20%). Early fruiter had a maximum level of tolerance against Citrus tristeza virus. CTV is replicated in the phloem cells of plants and is transmitted by the aphid specie Aphis gossypii. Thus, the maximum vector population mirrors the highest infection. Chemical plant nutrients, including micro-mix (Zn, Fe, Cu, Mn), NPK, zinc, and the insecticide Lufenoron, were used to limit the impact of CTV and A.gossyii. Lufenuron caused maximum disease inhibition, followed by the plant nutrients zinc, NPK, and micro-mix, respectively. However, Lufenoron significantly decreased the population of Aphis gossypi. The results indicate that the early fruiter has the lowest percent disease index and vector population. Moreover, Lufenuron is the best solution for controlling vector population and disease inhibition. Full article

The salinization and sodification of agricultural lands in arid and semi-arid regions of the world are two limiting factors in crop production. In India, an area of about 6.72 million ha is salt-affected, of which 3.77 million ha is sodic soil. To evaluate the reclamation potential of soil amendment, a laboratory incubation study was conducted at the Agricultural College and Research Institute, Tiruchirappalli (2022). Different soil amendments, viz., T₁-Pongamia GLM @ 6.25 t ha⁻¹, T₂-Pressmud @ 10 t ha⁻¹, T₃-CSR GROMOR 25 kg ha⁻¹, T₄-Marine gypsum 50% GR, T₅-Marine gypsum @ 50% GR + Pongamia GLM 6.25 t ha⁻¹, T₆-Marine gypsum 50% GR + Pressmud 10 t ha⁻¹, T₇-Marine gypsum 50% GR + CSR GROMOR 25 kg ha⁻¹ and T₈-Control (no amendments), were used for incubation. After 90 days of incubation, a pot culture using post-incubated soil was raised to study the seedling parameters of green gram, which was laid out in a randomized block design with three replications. The analysis of post-incubated soil using ICP-MS shows higher levels of cations, viz., Ca (+67%), Mg (+65%) and K (+66%), were found in marine gypsum @ 50% GR + CSR GROMOR @ 25 kg ha⁻¹ with lower values of pH (−15%), EC (−63%), ESP (−39%) and Na (−58%) compared to the control. The same treatment recorded higher chlorophyll, relative water content and seedling vigor index I and II in green gram. The results indicated that marine gypsum + CSR GROMOR had a positive impact on reducing soil sodicity and improving soil fertility. Full article

This study presents the first report of a Fusarium wilt in Cymbopogon citratus in Portugal. Fusarium is one of the most prominent genera of plant pathogens due to its wide range of hosts and mycotoxin production. The Fusarium fujikuroi species complex (FFSC) encompasses several threatening known plant pathogens. Cymbopogon citratus is a broadly distributed aromatic and medicinal plant rich in bioactive volatiles, which are relevant to several industries. The primary goal of this study was to identify and characterize the Fusarium fujikuroi species putatively responsible for the observed wilt. This report displays symptomatologic, cultural, morphologic, genetic, and cytogenomic characteristics associated with this fungus and disease. The cultural features included flat, white-colored colonies with filiform margins. Additionally, these colonies displayed abundant cottony aerial mycelia at the upper surface and orange-violet color at the lower surface. On Carnation Leaf-Piece Agar, septate fusoid macroconidia were present, displaying a flattened tapering toward the basal part and a number of septa ranging from one to four. The comparison between the amplified and aligned ITS sequences revealed 100% similarity between the isolate and the FFSC. Finally, a flow cytometry assay revealed an estimated genome size of 29.9 Mbp. This finding contrasts with other known pathogens from the Fusarium fujikuroi species complex. Ultimately, novel pathogens might be uncovered by exploring the mycobiome of diseased Cymbopogon citratus plants. Full article

The global demand for bottled king coconut water has led to a significant accumulation of empty king coconut husks in nut water export industries, posing challenges in managing and disposing of this agricultural waste. To address this issue, the production of king coconut husk ash (KCHA) has emerged as an eco-friendly solution. This product can be applied as a fertilizer, soil amendment, or after mixing with compost to enhance its nutrient value. This study aimed to determine the optimal cut size and moisture level for obtaining a high yield of KCHA with the maximum potassium content. The experiment involved drying full-, half-, quarter-, and chip-sized husks in a dehydrator at 60 °C for 0, 2, 4, 8, 12, 24, and 48 h. The findings revealed that reducing the particle size of the husks accelerated the drying process. The ash produced with chips exhibited the most favorable characteristics, reaching the desired dryness in a relatively shorter time while yielding the highest KCHA content. Moreover, the results indicated that the optimal duration for dehydrating the husks to produce ash was 24 h at 60 °C, resulting in the highest moisture loss. This processing condition facilitated the efficient conversion of king coconut husks into potassium-rich ash. Implementing these findings into the production of KCHA as a nutrient-rich fertilizer or soil amendment offers a sustainable approach to improving agricultural practices while reducing the dependence on synthetic fertilizers and mitigating the environmental challenges associated with their accumulation. Full article

Remote sensing technology (namely UAVs) has been used to monitor potato crops. As such, this study aims to analyze the relationship between the NDVI model and yield productivity in Solanum tuberosum L. plants from the Agria variety, submitted to a Ca biofortification process with two different concentrations (12 and 24 kg/ha) of CaCl₂ or Ca-EDTA. The NDVI values were collected six days after the six foliar applications and analyzed alongside the Ca content in the potato tubers (at harvest) and the total yield. The results highlight the fact that 24 kg/ha of CaCl₂ presented the lowest NDVI value, yet these plants did not show the lowest yield. Moreover, that same treatment presented the highest Ca biofortification index in tubers. Also, it seems that the NDVI can be used in decision making to improve crop management strategies, considering that it is an indicator for detecting plant growth or vigor; however, in this research, it is not sufficient for yield prediction. Full article