Utilization of Agro-Industrial Residues in the Rearing and Nutritional Enrichment of Zophobas atratus Larvae: New Food Raw Materials.

Edible insects are a potential alternative food source of high feed conversion efficiency and protein content. Zophobas atratus is an edible insect that adapts to different diets, enabling sustainable rearing by adding value to by-products and agro-industrial residues. This study aimed to evaluate the performance and nutritional characterization of Zophobas atratus larvae fed with different proportions of grape residue. Physicochemical analysis of the diets and larvae (AOAC procedures), fatty acid profile (chromatographic techniques), metals and non-metals (inductively coupled plasma optical emission spectrometry), larval mass gain, feed conversion efficiency, and mortality rate were assessed. The replacement of 25% of the conventional diet with grape residue increased lipid, ash, and fiber contents and reduced protein, carbohydrates, and energy. It promoted greater mass gain, lower mortality rate, and reduced larval growth time by 51%. Among the replacements, 25% resulted in the second-highest content of calcium, sodium, magnesium, and zinc, and the lowest content of potassium and phosphorus in the larvae. The 100% replacement resulted in the highest amounts of C18:2n6 (27.8%), C18:3n3 (2.2%), and PUFA (30.0%). Replacing 25% of the conventional diet with grape residue is equivalent to the conventional diet in many aspects and improves several larvae performance indices and nutritional values.

Lithium bioaccumulation in Lentinus crinitus mycelia grown in media with different lithium sources and pH values.

Lentinus crinitus bioaccumulates lithium in mycelia, but bioaccumulation may be affected by pH of the culture medium. Lithium is used in clinical practice as a mood stabilizer and antidepressant. This study aimed to assess the effect of culture medium pH and lithium source (LiCl or Li2CO3) on lithium bioaccumulation in vegetative mycelia of L. crinitus grown in malt extract broth. Lentinus crinitus U9-1 was cultured in malt extract broth supplemented with Li2CO3 or LiCl (50 mg L-1 lithium) in the pH range of 3.0 to 6.0. The pH was adjusted using HCl solution. The results showed that medium pH affected mycelial biomass production, lithium bioaccumulation in mycelial biomass, and lithium transfer from the culture medium to mycelial biomass. The effect of lithium source on the bioaccumulation capacity of mycelial biomass varied according to pH. At pH 4.0, both lithium sources stimulated mycelial biomass production compared to the control without the addition of lithium. At pH 5.5, Li2CO3 provided the highest lithium bioaccumulation in mycelial biomass. Lithium transfer from the culture medium to mycelia was highest in Li2CO3-supplemented cultures at pH 4.5. LiCl reduced hyphal width compared with Li2CO3 and the control. However, pH and lithium sources did not affect the formation of clamp connections in hyphae. For the first time, the influence of the pH of the culture medium on lithium bioaccumulation by Lentinus crinitus is reported. Finally, we conclude that the culture medium pH affected lithium transfer and bioaccumulation in mycelial biomass differently depending on the lithium source. Additionally, we report the presence of clamp connections in the hyphae of L. crinitus as an indicator of even growth.

Basidiocarp structures of Lentinus crinitus: an antimicrobial source against foodborne pathogens and food spoilage microorganisms.

Lentinus crinitus basidiocarps are an alternative to antimicrobials, but the stipe (24% basidiocarp) is discarded even with potential antimicrobial activity. This study evaluated the antimicrobial activity of L. crinitus basidiocarp pileus and stipe extracts against foodborne pathogens and food spoilage microorganisms. Basidiocarps of L. crinitus were grown in sugarcane bagasse and rice husks and the pileus and stipe methanolic extract was analyzed by broth microdilution method for antimicrobial activity against eight bacteria and eight fungi. The minimum bactericidal concentration values for pileus and stipe ranged from 0.40 to 0.50 mg mL- 1, for streptomycin from 0.10 to 0.50 mg mL- 1, and for ampicillin from 0.40 to 1.20 mg mL- 1. The minimum fungicidal concentration values for pileus and stipe ranged from 0.06 to 0.60 mg mL- 1, for bifonazole from 0.20 to 0.25 mg mL- 1, and for ketoconazole from 0.30 to 3.50 mg mL- 1. Extracts had bacteriostatic, bactericidal, fungistatic and fungicidal activity against all microorganisms, but with greater efficiency and specificity for some microorganisms. Both pileus and stipe are promising and sustainable alternatives for use in food, agricultural, and pharmaceutical industries.

Grape peel (Syrah var.) jam as a polyphenol-enriched functional food ingredient.

In this study, we evaluated the effects of the storage time on the physicochemical properties, bioactive compound content, and antioxidant capacity of jam prepared from grape peel extract to explore its potential as a supplementary food and/or functional ingredient. The ethanolic extract from Syrah var. grape peel exhibited high bioactive compound concentrations and antioxidant activity. The jam stability (prepared with 8.9% of extract) at 14°C was evaluated at 0, 15, 30, 45, and 60 days. The jam was found to contain high concentrations of polyphenolic compounds (137.0 ± 3.2 mg of gallic acid equivalent/100 g), total flavonoids (128.5 ± 23.0 mg of equivalent/100 g), and total anthocyanins (92.5 ± 4.0 mg of cyanidin equivalent/100 g). However, a large reduction in the flavonoid (70%-90%), anthocyanin (29%-35%), and phenolic (23%-30%) content was observed during storage. The free radical-scavenging activity (DPPH-), ferric reducing antioxidant power (FRAP), and ß-carotene-linoleic acid assays revealed the great antioxidant potential of the jam prepared from grape peel extract, which exhibited significant levels of radical-neutralizing activity, especially as determined by the DPPH method with EC50 values ranging from 2.3 ± 0.1 to 3.9 ± 0.1 µg/ml. High R 2 values (p > 0.90) were obtained for the correlation between the DPPH results and the concentrations of the compounds of interest. In summary, the high bioactive compound contents and antioxidant capacity of the jam produced from grape peel suggest that it may provide health benefits as a source of natural antioxidants upon incorporation to several food industry products.

Pilot-scale isolation and characterization of extracellular polymeric substances (EPS) from cell-free medium of Spirulina sp. LEB-18 cultures under outdoor conditions.

This objective of this work was to monitor the EPS production during the growth of Spirulina sp. LEB-18, evaluate the productivity and to characterize the exopolymers obtained on pilot-scale under outdoor conditions. The production of crude EPS occurred in all phases of biomass growth and was approximately ten folds higher than that biomass concentration of Spirulina sp. LEB-18 at the end cultivation, demonstrating the importance of the use of supernatant after harvesting of Spirulina to obtain high value bioproducts. The EPS extracted by Spirulina sp. LEB-18 are typically heteropolymers with one high molecular weight fraction (polysaccharides) with potential to be utilized as an alternative bioflocculant and another fraction of lower molecular mass (proteins). The presence of uronic acids, pyruvates and acyl groups of carbohydrates or carboxylic groups of amino acids in protein moiety is the main responsible for overall negative charge of EPS, which is also of biotechnological importance. Moreover, due to the pseudoplastic behavior of the solutions and high thermal stability, the obtained EPS can be widely applied in several industrial sectors, thus determining its technological and market potentiality.

Effects of photostimulation on the catabolic process of xenobiotics.

Light biotechnology is a promising tool for enhancing recalcitrant compounds biodegradation. Xenobiotics can cause a significant impact on the quality of the results achieved by sewage treatment systems due to their recalcitrance and toxicity. The optimization of bioremediation and industrial processes, aiming to increase efficiency and income is of great value. The aim of this study was to accelerate and optimize the hydrolysis of Remazol Brilliant Blue R by photo stimulating a thermophilic bacterial consortium. Three experimental groups were studied: control group; LED Group and Laser Group. The control group was exposed to the same conditions as the irradiated groups, except exposure to light. The samples were irradiated in Petri dishes with either a Laser device (λ660 nm, CW, θ = 0.04 cm2, 40 mW, 325 s, 13 J/cm2) or by a LED prototype (λ632 ±â€¯2 nm, CW, θ = 0.5 cm2, 145 mW, 44 s, 13 J/cm2). We found that, within 48-h, statistically significant differences were observed between the irradiated and the control groups in the production of RNA, proteins, as well as in the degradation of the RBBR. It is concluded that, both Laser and LED light irradiation caused increased cellular proliferation, protein production and metabolic activity, anticipating and increasing the catabolism of the RBBR. Being the economic viability a predominant aspect for industrial propose our results indicates that photo stimulation is a low-cost booster of bioprocesses.

Outdoor pilot-scale cultivation of Spirulina sp. LEB-18 in different geographic locations for evaluating its growth and chemical composition.

This study evaluated whether outdoor cultivation of Spirulina sp. in different geographical locations affected its growth and biomass quality, with respect to the chemical composition, volatile compound and heavy metal content, and thermal stability. The positive effect of solar radiation and temperature on biomass productivity in Spirulina sp. cultivated in the northeast was directly related to its improved nutritional characteristics, which occurred with an increase in protein, phycocyanin, and polyunsaturated fatty acid (mainly γ-linolenic) content. The biomass produced in Northeast and South Brazil showed high thermal stability and had volatile compounds that could be used as biomarkers of Spirulina, and their parameters were within the limits of internationally recognized standards for food additives; hence, they have been considered safe foods. However, the growth of crops in south Brazil occurred at lower rates due to low temperatures and luminous intensities, indicative of the robustness of microalgae in relation to these parameters.

New molecular features of cowpea bean (Vigna unguiculata, l. Walp) ß-vignin.

Cowpea seed ß-vignin, a vicilin-like globulin, proved to exert various health favourable effects, including blood cholesterol reduction in animal models. The need of a simple scalable enrichment procedure for further studies for tailored applications of this seed protein is crucial. A chromatography-independent fractionation method allowing to obtain a protein preparation with a high degree of homogeneity was used. Further purification was pursued to deep the molecular characterisation of ß-vignin. The results showed: (i) differing glycosylation patterns of the two constituent polypeptides, in agreement with amino acid sequence features; (ii) the seed accumulation of a gene product never identified before; (iii) metal binding capacity of native protein, a property observed only in few other legume seed vicilins.