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Industrial crops are becoming increasingly relevant as raw materials for different goods and services. Although there are many oilseed crops with industrial purposes, data about their production in Chile are scarce because the definition used by the Office of Agricultural Studies and Policies places agro‐industrial and industrial crops in the same category. Here, we review the available information about 12 industrial oleaginous crops at different levels of development (four native, two adventive and six introduced crops). Most of these crops have been evaluated for or are related to biodiesel production, despite the lack of commercial biodiesel production in Chile. Jojoba was the first industrial oilseed produced commercially in Chile; however, every year its production area decreases, and currently it does not exceed 100 ha. Sunflower and rapeseed, which are the first generation of raw materials for biodiesel production, have been poorly studied in Chile despite the large number of studies available on them worldwide. Camelina and castor bean have recently been studied; the former is produced in the south, while the latter is produced on the coastline in northern Chile. Further research is needed to improve the production and adaptation of these oilseed crops to climatic conditions in Chile; moreover, a new market must be opened to produce and commercialize their oils. Oilseed species native to Chile have not been extensively studied, and they represent an interesting option suitable for production under Chilean climatic conditions; this is particularly true for guindilla and chañar, because both can grow under different abiotic stresses. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The bioenergy crops such as energycane, miscanthus, and sorghum are being genetically modified using state of the art synthetic biotechnology techniques to accumulate energy‐rich molecules such as triacylglycerides (TAGs) in their vegetative cells to enhance their utility for biofuel production. During the initial genetic developmental phase, many hundreds of transgenic phenotypes are produced. The efficiency of the production pipeline requires early and minimally destructive determination of oil content in individuals. Current screening methods require time‐intensive sample preparation and extraction with chemical solvents for each plant tissue. A rapid screen will also be needed for developing industrial extraction as these crops become available. In the present study, we have devised a proton relaxation nuclear magnetic resonance (1H‐NMR) method for single‐step, non‐invasive, and chemical‐free characterization of in‐situ lipids in untreated and pretreated lignocellulosic biomass. The systematic evaluation of NMR relaxation time distribution provided insight into the proton environment associated with the lipids in the biomass. It resolved two distinct lipid‐associated subpopulations of proton nuclei that characterize total in‐situ lipids into bound and free oil based on their "molecular tumbling" rate. The T1T2 correlation spectra also facilitated the resolution of the influence of various pretreatment procedures on the chemical composition of molecular and local 1H population in each sample. Furthermore, we show that hydrothermally pretreated biomass is suitable for direct NMR analysis unlike dilute acid and alkaline pretreated biomass which needs an additional step for neutralization. [ABSTRACT FROM AUTHOR]

Oleaginous algae have the ability to synthesize a high level of triacylglycerol (TAG) and are considered as the next‐generation feedstock for biofuel production. Manipulating algal lipid biosynthetic pathways has potential to overproduce TAG and represents a feasible way toward bringing down algae‐derived biofuels production cost. Here we dissected functional roles and engineering potential of six diacylglycerol acyltransferase (DGAT) genes from the marine alga Phaeodactylum tricornutum. PtDGAT1, PtDGAT2B, and PtDGAT3, residing at the chloroplast endoplasmic reticulum (ER) readily for utilizing both chloroplast‐ and ER‐derived diacylglycerol, were transcriptionally correlated with TAG accumulation. Heterologous expression in yeast, in vitro assay and overexpression in P. tricornutum all supported that PtDGAT1 surpassed the other five PtDGATs in synthesizing TAG. Compared to wild type P. tricornutum, the PtDGAT1‐overexpressing strain produced more than doubled TAG and total lipids, which reached 57% and 73% of dry weight, respectively, record‐high levels ever achieved in this alga. Our results demonstrated the strategy of screening proper engineering targets and manipulating a single gene to pull carbon flux to lipids for TAG hyper‐accumulation without growth compromise. The engineered alga with a great trait improvement may serve as a potent lipid producer for production uses. [ABSTRACT FROM AUTHOR]

Microalgae have been shown as a potential bioresource for food, biofuel, and pharmaceutical products. During the growth phases with corresponding environmental conditions, microalgae accumulate different amounts of various metabolites. We quantified the neutral lipids accumulation and analyzed the swimming signatures (speed and trajectories) of the motile green alga, Dunaliella primolecta, during the lag–exponential–stationary growth cycle at different nutrient concentrations. We discovered significant changes in the neutral lipid content and swimming signatures of microalgae across growth phases. The timing of the maximum swimming speed coincided with the maximum neutral lipid content and both maxima occurred under nutrient stress at the stationary growth phase. Furthermore, the swimming trajectories suggested statistically significant changes in swimming modes at the stationary growth phase when the maximum intracellular neutral lipid content was observed. Our results provide the potential exploitation of microalgal swimming signatures as possible indicators of the cultivation conditions and the timing of microalgal harvest to maximize the lipid yield for biofuel production. The findings can also be implemented to explore the production of food and antibiotics from other microalgal metabolites with low energy costs. [ABSTRACT FROM AUTHOR]

This section presents a review of the scientific literature published in 2018 on topics relating to sustainable bioenergy from biofuel residues and waste. This review is divided into the following sections: Feedstocks, Bioethanol, Biodiesel, Biohydrogen, Hydrogen, Biofuel Residues, Microalgae, and Lignocelluloses. [ABSTRACT FROM AUTHOR]

BACKGROUND The effects of the initial nitrogen concentration, as well as of two‐stage and prolonged cultivation on the growth rate, lipid and protein content of Chlorella vulgaris were examined. Additionally, a kinetic model of specific growth rate in the exponential growth phase (µexp) was developed as a function of initial nitrogen concentration. RESULTS: As the initial nitrogen concentration in the culture medium increased, the total biomass production and µexp went through a maximum at 300 mg N L−1 and at 200 mg N L−1, respectively. The lipid content was found to be highly dependent on the initial nitrogen concentration and increased from 9.0% to 29.6% as the nitrogen concentration varied from 800 to 10 mg N L−1, respectively. Cultivation in two stages resulted in an increase of the lipid content of the biomass from 15.4% to 24.9%, while prolonged cultivation led to an increase of the lipid content from 15.4% to 23.0%. CONCLUSION: Cultivation under optimum nitrogen concentration can lead to increased biomass production. In addition, optimization of lipid production can be carried out by a two‐stage cultivation mode or by prolonged cultivation. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This section presents a review of the scientific literature published in 2017 on topics relating to sustainable bioenergy from biofuel residues and waste. This review is divided into the following sections: Feedstocks, Bioethanol, Biodiesel, Biohydrogen, Hydrogen, Biofuel Residues, Microalgae, Lignocelluloses and other topics. [ABSTRACT FROM AUTHOR]

SUMMARY: Microalgae are considered a very promising alternative for biofuel production. Several strategies were developed to modulate and improve algae metabolites production to meet the requirements for biodiesel production. Most previous research evidenced that the increase of the lipid content is accompanied by a decrease of the biomass production, which increases the cost of the downstream processing. Hence, the challenge is to find special culture conditions that increase the lipid and the biomass productivities simultaneously. In the present work, we developed a strategy for the improvement of biomass and lipid productivities in a novel local microalga isolate, Chlorocystis sp. QUCCCM14, which was not previously known as a promising strain. Indeed, culturing QUCCCM14 using f/2 medium with 10× NaH2PO4 (0.15 g L−1 NaNO3 and 5.6 mg L−1 NaH2PO4) resulted in an improvement of 3.178 folds the lipid productivity reaching 56.121 mg L−1 day−1 and enhanced the biomass productivity reaching 141.363 mg L−1 day−1, simultaneously. Comparative analyses of the FAME profiles demonstrated that fed‐batch culture with phosphate or nitrate separately leads to a high production of the omega 3 fatty acids (Linolenic acid), whereas fed‐batch culture with phosphate and nitrate simultaneously increased the production of fatty acids suitable for biodiesel production. [ABSTRACT FROM AUTHOR]

Abstract: As promising alternatives to fossil‐derived oils, microbial lipids are important as industrial feedstocks for biofuels and oleochemicals. Our broad aim is to increase lipid content in oleaginous yeast through expression of lipid accumulation genes and use Saccharomyces cerevisiae to functionally assess genes obtained from oil‐producing plants and microalgae. Lipid accumulation genes DGAT (diacylglycerol acyltransferase), PDAT (phospholipid: diacylglycerol acyltransferase), and ROD1 (phosphatidylcholine: diacylglycerol choline‐phosphotransferase) were separately expressed in yeast and lipid production measured by fluorescence, solvent extraction, thin layer chromatography, and gas chromatography (GC) of fatty acid methyl esters. Expression of DGAT1 from Arabidopsis thaliana effectively increased total fatty acids by 1.81‐fold above control, and ROD1 led to increased unsaturated fatty acid content of yeast lipid. The functional assessment approach enabled the fast selection of candidate genes for metabolic engineering of yeast for production of lipid feedstocks. [ABSTRACT FROM AUTHOR]

This review includes works published in the general scientific literature during 2016 on the production of bioenergy and biofuel from waste residues generated during bioethanol and biodiesel production with a brief overview of current and emerging feedstocks. A section of this review summarizes literature on culturing algae for biofuels including bioreactors and open pond cultivation systems with the utilization of inorganic and organic sources of nutrients. New methods applicable to the mass culture of algae are highlighted. Algal cell harvesting and oil extraction techniques are discussed along with policies and economics. [ABSTRACT FROM AUTHOR]

BACKGROUND In this study, the use of vegetable waste as a potential source of raw material for biofuel production was investigated. The microalga Chlorella vulgaris was used to maximize the production of lipids and carbohydrates. The culture medium was prepared with vegetable waste and diluted in the following proportions of medium:water: 1:0, 1:1, 1:2 and 1:3; the resulting solutions were adjusted for three different pH values (5.5, 7.2, 8.5). For a comparative analysis, modified CHU-10 medium was used. RESULTS The initial concentration of carbon in the medium was 279.6 ± 3.5 mg L−1, while nitrogen was 11.22 ± 1.32 mg L−1. The growth in heterotrophic conditions was performed for 21 days, during which it was observed that higher concentrations of biomass and higher productivity of lipids and carbohydrates were obtained in cultures performed in medium without dilution (1:0) and pH 5.5; however, higher yields of lipids and carbohydrates were obtained when the medium was diluted in the proportion 1:3 and with alkaline pH. CONCLUSION The results of this study should encourage the use of vegetable waste as raw material for the production of microalgae rich in lipids and carbohydrates for the production of environmentally friendly fuels. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This review includes works published in the general scientific literature during 2015 on the production of bioenergy and biofuel from waste residues generated during bioethanol and biodiesel production with a brief overview of current and emerging feedstocks. A section of this review summarizes literature on culturing algae for biofuels including bioreactors and open pond cultivation systems with the utilization of inorganic and organic sources of nutrients. New methods applicable to the mass culture of algae are highlighted. Algal cell harvesting and oil extraction techniques tested and developed for algae discussed alongwith policies and economics are also provided. [ABSTRACT FROM AUTHOR]

This review includes works published in the general scientific literature during 2014 on the production of bioenergy and biofuel from waste residues generated during bioethanol and biodiesel production with a brief overview of current and emerging feedstocks. Another section of this review summarizes literature on culturing algae for biofuels including bioreactors and open pond cultivation systems with the utilization of inorganic and organic sources of nutrients. New methods applicable to the mass culture of algae are highlighted. Algal cell harvesting and oil extraction techniques tested and developed for algae are also discussed. [ABSTRACT FROM AUTHOR]

This review includes works published in the general scientific literature during 2013 on the production of bioenergy and biofuel from waste residues generated from bioethanol and biodiesel production with a brief overview of current and emerging feedstocks. A later section of this review summarizes literature on culturing algae for biofuels including bioreactors and open pond cultivation systems with the utilization of inorganic and organic sources of nutrients. New methods applicable to the mass culture of algae are highlighted. Algal cell harvesting and oil extraction techniques tested and developed for algae are also discussed. [ABSTRACT FROM AUTHOR]

Calotropis procera is a soft-wooded, evergreen, perennial shrub species which grows in a variety of environments including dry habitats such as the Brazilian semi-arid region. This study aimed to evaluate the variation in the oil content and fatty acid composition of C. procera seeds from four climatically different locations in the state of Pernambuco in the northeast of Brazil. The seed oil content of C. procera ranged from 19.7 to 24.0 %. Five main fatty acids were identified, with a predominance of unsaturated linoleic and oleic acids (approximately 70 %). Our results suggesting that environmental conditions influenced the seed oil biosynthesis of C. procera, because the localities with high temperature and low precipitation had increased oil content and total biosynthesis of saturated fatty acids. Multivariate analysis showed high similarity among three localities which share certain physiographic characteristics and climatic conditions such as temperature and precipitation values. The oil profile of C. procera presents interesting features that highlight its potential as a future alternative for the biodiesel market, especially in semi-arid regions. [ABSTRACT FROM AUTHOR]

Currently, very few studies address the relationship between diversity and biomass/lipid production in primary producer communities for biofuel production. Basic studies on the growth of microalgal communities, however, provide evidence of a positive relationship between diversity and biomass production. Recent studies have also shown that positive diversity-productivity relationships are related to an increase in the efficiency of light use by diverse microalgal communities. Here, we hypothesize that there is a relationship between diversity, light use, and microalgal lipid production in phytoplankton communities. Microalgae from all major freshwater algal groups were cultivated in treatments that differed in species richness and functional group richness. Polycultures with high functional group richness showed more efficient light use and higher algal lipid content with increasing species richness. There was a clear correlation between light use and lipid production in functionally diverse communities. Hence, a powerful and cost-effective way to improve biofuel production might be accomplished by incorporating diversity related, resource-use-dynamics into algal biomass production. [ABSTRACT FROM AUTHOR]

The extraction efficiency of microalgae lipids with aqueous isopropanol (IPA) was investigated and compared with the extraction of oil from full-fat soy flour. The effects of the type of microalgae ( Scenedesmus sp. and Schizochytrium limacinum), cell rupture, and IPA concentration on the yield of oil and non-lipid biomass were determined. The oil yield from intact cells of Scenedesmus was 86-93 % with 70, 88, or 95 % (by wt) IPA. Ultrasonic cell rupture prior to oil extraction decreased the oil yield of Scenedesmus to 74 % when extracting with 70 % IPA. The oil yield from intact cells of S. limacinum was <23 % regardless of the IPA concentration, but ruptured cells gave a 94-96 % oil yield with 88 or 95 % IPA. The different response of the two microalgae to extraction with IPA is possibly caused by differences in the cell wall structure and type and amount of polar lipids. The oil yield from soy flour with 88 and 95 % IPA was 93-95 %, which was significantly greater than yields with 50 and 70 % IPA. Cell rupture had no effect on soy flour extraction. In general, the oil yield from the ruptured cells of both microalgae and soy flour increased with increasing IPA concentration. [ABSTRACT FROM AUTHOR]

Common methods for assaying acyl-CoA:diacylglycerol acyltransferase (DGAT) enzymatic activity rely upon radiolabeled substrates or product assay. We developed a novel assay that directly quantifies endogenous DGAT activity through the use of a fluorescently labeled substrate. We performed this assay with microsomal protein, 2-(6-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)hexanoyl-1-hexadecanoyl- sn-glycero-3-diacylglycerol (NBD-DAG), and oleoyl-CoA substrates. DGAT activity was analyzed in three species of algae as well as rat liver. The protocol proved to be sensitive and reliable. This assay may be used to facilitate research in the areas of biodiesel, oilseed crops, and triacylglycerol-related human pathologies. [ABSTRACT FROM AUTHOR]

Common methods for assaying acyl-CoA:diacylglycerol acyltransferase (DGAT) enzymatic activity rely upon radiolabeled substrates or product assay. We developed a novel assay that directly quantifies endogenous DGAT activity through the use of a fluorescently labeled substrate. We performed this assay with microsomal protein, 2-(6-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)hexanoyl-1-hexadecanoyl- sn-glycero-3-diacylglycerol (NBD-DAG), and oleoyl-CoA substrates. DGAT activity was analyzed in three species of algae as well as rat liver. The protocol proved to be sensitive and reliable. This assay may be used to facilitate research in the areas of biodiesel, oilseed crops, and triacylglycerol-related human pathologies. [ABSTRACT FROM AUTHOR]