Towards Functional Insect Feeds: Agri-Food By-Products Enriched with Post-Distillation Residues of Medicinal Aromatic Plants in Tenebrio molitor (Coleoptera: Tenebrionidae) Breeding

Sustainability, circular economy and alternative production systems are urgent imperatives for humanity and animal husbandry. Unless wasted, agri-food by-products can offer a promising source of high value. We evaluated the effect of rice bran (RB), corncob (CC), potato peels (PP), solid biogas residues (BR), and olive-oil processing residuals (OR), as alternative substrates to wheat bran (WB as control), on the growth and nutritional value of Tenebrio molitor during its breeding for animal feeds and/or human consumption. Innovation-wise, we further investigated the substrate supplementation (0, 10, 20%) with post-distillation residues of Mediterranean aromatic-medicinal plants (MAPs: lavender, Greek oregano, rosemary, olive; 1:1:1:1 ratio). Tenebrio molitor larvae (TML) were reared in all the studied substrates, and TML and diets’ proximate and fatty acid compositions as well as total phenol and flavonoid content and antioxidant potential were assessed using standard procedures. After statistical analysis of correlations, we observed that CC promoted oviposition and progeny survival; larval weight and dry matter were positively affected mainly by dietary energy and fat content; number of TML and/or larval weight increased using 10% MAPs inclusion in WB, RB and OR or RB, OR, BR and PP, respectively, which did not affect protein content; TML fatty acid composition decreased the content of saturated ones and increased that of mono-unsaturated ones; MAPs residues had an apparent favorable impact on total phenolic content and antioxidant activity of each substrate, with RB displaying the highest capacity and content. These findings indicate that alternative substrates can be exploited and their enrichment with natural phenolics is able to influence T. molitor growth, offering highly beneficial and nutritional value.

Hydrocracking of Heavy Fischer–Tropsch Wax Distillation Residues and Its Blends with Vacuum Gas Oil Using Phonolite-Based Catalysts

The Fischer–Tropsch heavy fraction is a potential feedstock for transport-fuels production through co-processing with fossil fuel fraction. However, there is still the need of developing new and green catalytic materials able to process this feedstock into valuable outputs. The present work studies the co-hydrocracking of the Fisher–Tropsch heavy fraction (FT-res.) with vacuum gas oil (VGO) at different ratios (FT-res. 9:1 VGO, FT-res. 7:3 VGO, and FT-res. 5:5 VGO) using phonolite-based catalysts (5Ni10W/Ph, 5Ni10Mo/Ph, and 5Co10Mo/Ph), paying attention to the overall conversion, yield, and selectivity of the products and properties. The co-processing experiments were carried out in an autoclave reactor at 450 °C, under 50 bars for 1 and 2 h. The phonolite-based catalysts were active in the hydrocracking of FT-res.:VGO mixtures, presenting different yields to gasoline, diesel, and jet fuel fractions, depending on the time of reaction and type of catalyst. Our results enable us to define the most suitable metal transition composition for the phonolite-based support as a hydrocracking catalyst.

Isolation of guaiene from crude and distillate patchouli oil extracted by molecular distillation

Guaiene is one of the components of sesquiterpenes that affects the patchouli oil fragrance. It is commonly used in the pharmaceutical industry and is also used as a flavoring and fragrance agent in the food industry. The objective of this study was to obtain the highest content of guaiene and to investigate the effect of the isolation stage by the molecular distillation process. Crude and distillate fraction patchouli oil samples were introduced into the molecular distillation system. The process conditions applied were first-stage and second-stage molecular distillation. Parameters observed were in terms of chemical composition and color. Results obtained the highest content of a-guaiene in the patchouli oil fraction distillate provided by second-stage molecular distillation (23.53%). However, the highest content of A-guaiene was revealed in second-stage molecular distillation residues (33.15%) of patchouli oil fraction distillate samples. The chromaticity value of the second stage distillate was yellow while the residue was yellow-red, respectively.

Investigation of Heavy and Trace Metals in Some Kurdistan Region Crude Oils by Spectroscan MAX-G

Four types of Kurdistan crude oils have been studied to determine the heavy and trace metals. The significance of determining trace elements that exist in crude oils is helpful for further information about exploration, production and the refining process. In this work crude oil can be separated into products such as (gasoline, kerosene, diesel, and atmospheric distillation residue +350°C) by using atmospheric distillation unit and vacuum distillation unit. The trace metals can be determined with acceptable accuracy and precision by spectroscan MAX-G. However, the values of Ni concentration were the best in accuracy among the group of metals of interest. The average values of the results will be employed as reference values of the trace metal content in the coming discussion and using Ni and V as test elements. The crude oil samples are characterized by with a dominance of V over Ni with a V/Ni ratio of 3.7 to 2.5. Trace element analysis of the five metals in crude oils and atmospheric distillation residues +350°C, for each crude oils and atmospheric distillation residues +350°C is investigated, samples of these areas has not been previously examined for trace element contents. In this study to find the relation between metals in crude oils and atmospheric distillation residue of samples. To detect the concentration of trace elements by using this instrument.

Role of Gln79 in Feedback Inhibition of the Yeast γ-Glutamyl Kinase by Proline

Awamori, the traditional distilled alcoholic beverage of Okinawa, Japan, is brewed with the yeast Saccharomyces cerevisiae. During the distillation process after the fermentation, enormous quantities of distillation residues containing yeast cells must be disposed of, and this has recently been recognized as a major problem both environmentally and economically. Proline, a multifunctional amino acid, has the highest water retention capacity among amino acids. Therefore, distillation residues with large amounts of proline could be useful in cosmetics. Here, we isolated a yeast mutant with high levels of intracellular proline and found a missense mutation (Gln79His) on the PRO1 gene encoding the γ-glutamyl kinase Pro1, a limiting enzyme in proline biosynthesis. The amino acid change of Gln79 to His in Pro1 resulted in desensitization to the proline-mediated feedback inhibition of GK activity, leading to the accumulation of proline in cells. Biochemical and in silico analyses showed that the amino acid residue at position 79 is involved in the stabilization of the proline binding pocket in Pro1 via a hydrogen-bonding network, which plays an important role in feedback inhibition. Our current study, therefore, proposed a possible mechanism underlying the feedback inhibition of γ-glutamyl kinase activity. This mechanism can be applied to construct proline-accumulating yeast strains to effectively utilize distillation residues.

Carcass Traits and Meat Quality of Fat-Tailed Lambs Fed Rosemary Residues as a Part of Concentrate

Facing climate change implications on feeds unavailability, unconventional resources are being considered with a growing interest such as aromatic plant distillation residues with a two-fold object, enhancing meat quality by increasing the antioxidant properties and reducing feed prices which are often imported though expensive. Hence, this study aims to assess the effects of rosemary distillation residues (RR) incorporation in concentrate associated to two nitrogen sources as a substitute for standard concentrate on lamb’s growth, carcass traits and meat quality. For this, 24 Barbarine male lambs (3 months old, 17.83 ± 2.6 kg body weight) were divided into three groups. All lambs received individually 600 g of oat hay as roughage and 600 g of standard concentrate for control group, 600 g of concentrate based on RR and soybean meal for RRS group and 600 g of concentrate based on RR and faba bean for RRF group. After 65 days of experiment, all lambs were slaughtered. Phenolic and tocopherol intakes were significantly higher for both RR groups compared to control (p < 0.05). Growth, carcass weights, dressing percentages and non-carcass component weights were unaffected by the diet (p > 0.05). Moreover, regional and tissular compositions and meat physical properties were similar irrespective of the diet (p > 0.05). All color parameters were similar among groups (p > 0.05). However, meat produced by lambs receiving RR-based concentrate was richer on vitamin E and polyphenol contents than control lambs (p < 0.05). Rosemary by-products may substitute the standard concentrate resulting in similar lamb’s growth and carcass traits, while improving meat quality by increasing vitamin E content, which could improve its antioxidant power.