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Hemp seeds (HS) constitute a rich nutrient source and contain γ‐linolenic acid (GLA, 18:3, n‐6), which is a healthy fatty acid (FA). The objectives of this research are i) to look for GLA‐rich varieties of unhusked hemp seeds (UHS) and commercial hulled hemp seeds (HHS); ii) to check the influence of different extracting systems on both oil yield and FA profiles; iii) to test a simultaneous oil extraction/GLA‐enrichment process looking to improve GLA content. Hop and European hackberry seeds (both from Cannabaceae family) are also analyzed for comparative purposes. GLA is the most discriminant FA among UHS varieties, ranging in both UHS and HHS seeds from 0.5% to 4.5% of total FA, while hop seeds are the richest GLA source from Cannabaceae (7.2% of total FA). The extraction system selected for hemp seeds processing has a clear influence on oil yields, although, the FA profiles are slightly modified. The use of n‐hexane and n‐hexane:acetone in extractions allows an improvement in oil yields at the same GLA percentage. A process comprising saponification and subsequent cooling allows the improvement of GLA percentage in both hemp and hop seeds extracts at values higher than 10% of total FA, at high yields (>70%).Practical Applications: The global HS market increases significantly year after year and the demand of hemp products is increasing rapidly. The natural GLA sources in nature are limited, and although hemp contains GLA, this reaches low percentages in the oil. Hemp is a well‐established crop with highly standardized agricultural technologies, thus, the development of any well‐designed processes feasible for application in oil extraction industries, would allow the development of new GLA‐based functional seed oils. This would boost the development of the agricultural and food industries dedicated to revaluing hemp products.

Two polyunsaturated fatty acids, docosahexaenoic acid (DHA) and arachidonic acid (ARA), as well as derivatives, such as eicosanoids, regulate different activities, affecting transcription factors and, therefore, DNA transcription, being a critical step for the functioning of fatty-acid-derived signaling. This work has attempted to determine the in vitro anticancer activities of these molecules linked to the gene transcription regulation of HT-29 colorectal cancer cells. We applied the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test along with lactate dehydrogenase and caspase-3 assays; proteome changes were assessed by "sequential windowed acquisition of all theoretical mass spectra" quantitative proteomics, followed by pathway analysis, to determine the affected molecular mechanisms. In all assays, DHA inhibited cell proliferation of HT-29 cells to a higher extent than ARA and acted primarily by downregulating proteasome particles, while ARA presented a dramatic effect on all six DNA replication helicase particles. The results indicated that both DHA and ARA are potential chemopreventive agent candidates.

The aim of this work is to assess the fatty acid (FA) profiles, the lipid classes, and the positional distribution of FA within the triacylglycerol (TAG) structure of the lipids extracted from Lepidoptera larvae, compared with Diptera and Coleoptera ones. The major essential FA in most species was α‐linolenic acid (ALA), at 62.5 mol% of total FA in Caligo memnon. Oleic acid (OA) was found in high amounts in Galleria mellonella, at 44.8 mol% of total FA. The n‐6/n‐3 ratio was below 1 in 12 of the 15 species surveyed, reaching 14.8 in Oryctes nasicornis. As for lipid fractions, an increase in the amounts of stearic and linoleic acids in the phospholipids fraction was observed. Distribution of FA in the sn‐2 position of TAG is assessed through enzymatic hydrolysis reaction. Bombyx mori larvae contain ALA at 49.1 mol% of total FA at the sn‐2 position of TAG, while OA is the main FA in sn‐2 position in G. mellonella (88.5 mol% of total FA). Overall, Lepidoptera larvae constitute a rich source of specifically located at the sn‐2 position OA and ALA, and similar or better than current sources. Initial data on other insect orders also points in this direction. Practical Applications: The present study develops knowledge about the lipid classes of Lepidoptera larvae, as well as on their regiospecific FA profiles. The data from Lepidoptera species are compared to other ones obtained from samples belonging to Diptera and Coleoptera. Insects are rich in essential amino acids; therefore if they contain omega‐3 and omega‐9 FA, would be healthy alternatives to other commonly consumed animal foods, which tend to be rich in saturated and omega‐6 FA. Therefore, it is necessary to check different species to know their FA profile, as well as both the structure of their TAG and their lipid classes. Lepidoptera larvae constitute an alternative source of OA‐ and ALA‐rich oils, which can be devoted for food use, as well as for using in the food and pharmaceutical industries, with agronomic implications. The lipid classes and the regiospecific fatty acid profiles of several Lepidoptera larvae (Class Insecta) with different geographic origin and compared to that of Coleoptera and Diptera is achieved. Enzymatic hydrolysis reaction shows that oleic and α‐linolenic acids are preferably located at the sn‐2 position of triacylglycerols in most of the analyzed species. According to the results of this work, new functional oils extracted from various insect species can be obtained.

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