Landscape of Sequence Variations in Homologous Copies of FAD2 and FAD3 in Rapeseed(Brassica napus L.)Germplasm with High/Low Linolenic Acid Trait

Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil accumulation.In this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype ZS11.The expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and SW.The three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and BnFAD3.A3.In A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were detected.The profile of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous studies.The mutations in BnFAD3 in the high-ALA accessions are reported for thefirst time.In identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes.

Preparation of High-Purity Linolenic Acid from Oil of Lithospermum Erythrorhizon by Urea Inclusion and Column Chromatography

Aim To separate high purity linolenic acid from the oil of Lithospermumerythrorhizon growing in the Northeast of China. Methods Urea inclusion and column chromatographywere used. Results Unsaturated fatty acid was separated, with a purity of 99.30 wt% of linolenicacid. Conclusion The experiment shows excellent reproducibility and high feasibility for industrialproduction.

Preparation and Charaterization of Self-assembled Nanoparticles Based on Linolenic-acid Modified Chitosan

Chitosan was modified by conjugating coupling with linolenic acid through the 1-ethyl-3-（3-dimethylami- nopropyyl） carbodiimide （EDC）-mediated reaction. The degree of substitution 1.8% （ i.e. 1.8 linolenic acid group per 100 anhydroglucose units） was measured by ^1H NMR. The critical aggregation concentration （CAC） of the self-aggregate of hydrophobically modified chitosan was determined by measuring the fluorescence intensity of the pyrene as a fluorescent probe. The CAC value in phosphate-buffered saline （PBS） solution （pH 7.4） was 5 × 10^-2 mg mL^-1. The average particle size of selfaggregates of hydrophobically modified chitosan in PBS solution （pH7.4） was 210.8 nm with a unimodal size distribution ranging from 100 to 500 nm. Transmission electron microscopy （TEM） study showed that the formation of near spherical shape nanoparticles has enough structural integrity. The loading ability of hydrophibically modified chitosan （LA-chitosan） was investigated by using bovine serum albumin （BSA） as the model. The loading capacity of self-aggregated nanoparticles increases （ 19.85 % ± 0.04 % to 37.57 % ± 0.25 % ） with the concentration of BSA （0.1-0.5 mg mL^-1 ）.

Effects of Ce^(3+) on improvement of spectral characteristics and function of chloroplasts damaged by linolenic acid in spinach

Linolenic acid has great effects on the structure and function of chloroplast. We studied the effects of Ce3＋ on the improvement of chloroplast spectral characteristics and oxygen evolution damaged by linolenic acid in spinach. Results showed that Ce3＋ could decrease the light absorption increased by linolenic acid and promote the distribution of excitation energy to PS II and alleviate the decrease of PS Ⅱ fluo- rescence yield caused by linolenic acid. The linolenic acid treatments in various concentrations reduced the oxygen-evolving rate of chloroplasts, but the rate was accelerated since adding Ce3＋.

Alleviation effects of Ce^(3+) on inhibition of photochemical activity caused by linolenic acid in spinach chloroplast

Linolenic acid has great effects on the structure and function of chloroplast. The function of Ce^3＋ on the improvement of chloroplast photoreduction activity and oxygen evolution damaged by linolenic acid in spinach by in vitro investigation was studied. Results showed that adding Ce^3＋ to the linolenic acid treated chloroplast could greatly decrease the reduction linolenic acid exerted on the whole chain electron transport rate and the photoreduction activity of photosystem Ⅱ （PSII） and photosystem Ⅰ （PSI） as well as the oxygen evolution rate of chloroplast. It indicated that Ce^3＋ had the ability to relieve the inhibition of the photochemical reaction of chloroplast caused by linolenic acid to some extent.

Cotton BLH1 and KNOX6 antagonistically modulate fiber elongation via regulation of linolenic acid biosynthesis

BEL1-LIKE HOMEODOMAIN(BLH)proteins are known to function in various plant developmental processes.However,the role of BLHs in regulating plant cell elongation is still unknown.Here,we identify a BLH gene,GhBLH1,that positively regulates fiber cell elongation.Combined transcriptomic and biochemical analyses reveal that GhBLH1 enhances linolenic acid accumulation to promote cotton fiber cell elongation by activating the transcription of GhFAD7A-1 via binding of the POX domain of GhBLH1 to the TGGA cis-element in the GhFAD7A-1 promoter.Knockout of GhFAD7A-1 in cotton significantly reduces fiber length,whereas overexpression of GhFAD7A-1 results in longer fibers.The K2 domain of GhKNOX6 directly interacts with the POX domain of GhBLH1 to form a functional heterodimer,which interferes with the transcriptional activation of GhFAD7A-1 via the POX domain of GhBLH1.Overexpression of GhKNOX6 leads to a significant reduction in cotton fiber length,whereas knockout of GhKNOX6 results in longer cotton fibers.An examination of the hybrid progeny of GhBLH1 and GhKNOX6 transgenic cotton lines provides evidence that GhKNOX6 negatively regulates GhBLH1-mediated cotton fiber elongation.Our results show that the interplay between GhBLH1 and GhKNOX6 modulates regulation of linolenic acid synthesis and thus contributes to plant cell elongation.

A PRELIMINARY STUDY ON THE INTRODUCTION OF DESCURAINIA SOPHIA, AN OIL PLANT SPECIES FOR INDUSTRIAL USES

The authors had collected some cruciferous oil plants with high linolenic acid content in Sichuan Province. The result of fatty acid analysis had shown that Malcolmia africrma (L.) R. Br. and Arabis hirsuta (L.) Scop, have a higher linolenic acid content of 57.37% and 51.38% respectively . Thus they are worthy for further study. Descurainia sophia (L.) Webb. ex Prantl, especially that collected from Hongyuan County, has a high seed oil content of 44.17% , a linolenic acid content of 40.9 % and a high seed yield of 1 264.5 kg/hm2 . It is suggested that this oil plant species can be introduced for industrial utilization.

Determination of Fatty Acid Composition by GC-MS and Potential Antioxidant and Antibacterial Properties of Rumex hastatus and Cytisus scoparius Seeds Grown in Kashmir

Rumex hastatus D. Don and Cytisus scoparius Linn. are medicinally important plants used in Ayurveda and food, areenriched with remarkable nervine, diuretic, sedative and various other therapeutic properties. In this study Soxhlet extractionproduces higher yield of seed extracts. Gas chromatography-mass spectrometry was used to determine fatty acid composition ofpetroleum ether extracts (PE). The major fatty acids were Linolenic acid 53.53% in R. hastatus and linoleic acid 59.42% in C.scoparius. Palmitic acid was also found in significant amount (16.58% and 19.33%) in R. hastatus and C. scoparius respectively. Thechloroform (RCF, CCF), ethyl acetate (REA, CEA), acetone (RAT, CAT) and methanol (RMT, CMT) extracts of R. hastaus and C.scoparius respectively, were examined for their antioxidant activity using 2,2-di-phenyl-1-picrylhydrazyl (DPPH), nitrobluetetrazolium (NBT), hydrogen peroxide (H2O2), 2,2ˈ-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavengingassay and antibacterial activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus by Agar disc diffusionmethod. All the extracts showed good radical scavenging and antibacterial activities compared to butylated hydroxyltoluene andstreptomycin respectively. However, dominant radical scavenging effect was observed at 100 μg/mL and 200 μg/mL concentrationsof extracts and dominant zone of inhibition was shown by CAT, CMT, RAT and REA extracts. This study exhibited beneficialproperties of these plants as an ingredient (unsaturated fatty acids) for the formulation of various functional foods and a source ofnatural antioxidant and antibacterial agents for drug, design and development.

Water deficit and cold stress on the evening primrose seed quality

Evening primrose is a valuable oilseed crop with pharmaceutical and nutritional supplementation. Due to presence of valuable and rare gamma linolenic fatty acid, research on this plant has been started since 1970s by German and Britain scientists. Information about evening primrose cultivation is going to rise. Following to pervious studies the goal of this experiment was to clarify the effect of water and temperature stresses on seed yield and seed quality. Results showed that seed yield was significantly influenced by low temperature and water deficit. Plants grown under cold stress during rosette stage produced a lower seed yield than controls. The lowest seed yield was observed in the plants grown under permanent stress. Although the oil content of seeds was not influenced by low temperature stress, water stress strongly influenced the oil content and water stress stimulates oil accumulation. Like oil content, the GLA production seems to be increased under water stress conditions.

Effectiveness of omega-3 polyunsaturated fatty acids against microbial pathogens

Microorganisms provide both beneficial and harmful effects to human beings. Beneficial effects come from the symbiotic relationship that exists between humans and microbiota, but then several human illnesses have turned some friendly microbes into opportunistic pathogens, causing several microbial-related diseases. Various efforts have been made to create and utilize antimicrobial agents in the treatment and prevention of these infections, but such efforts have been hampered by the emergence of antimicrobial resistance. Despite extensive studies on drug dis- covery to alleviate this problem, issues with the toxicity and tolerance of certain compounds and continuous microbial evolution have forced researchers to focus on screening various phytochemical dietary compounds for antimicrobial activity. Linolenic acid and its derivatives （eicosapentaenoic acid and docosahexaenoic acid） are omega-3 fatty acids that have been studied due to their role in human health, being important for the brain, the eye, the cardiovascular system, and general human growth. However, their utilization as antimicrobial agents has not been widely appreciated, perhaps due to a lack of understanding of antimicrobial mechanisms, toxicity, and route of administration. Therefore, this review focuses on the efficacy, mechanism, and toxicity of omega-3 fatty acids as alternative therapeutic agents for treating and preventing diseases associated with pathogenic microorganisms.

Production of hispidin polyphenols from medicinal mushroom Sanghuangporus vaninii in submerged cultures

Objective: The medicinal mushroom Sanghuangporus vaninii produces pharmaceutically valuable hispidin polyphenols in natural habitats. However, due to the slow growth in nature, S. vaninii grown in the field(sclerotia) is not reliable for pharmaceutical purposes. Although higher biomass of fungal mycelia can be obtained in submerged cultures, the accumulation of hispidin polyphenols is rare.Methods: In this study, the polyunsaturated fatty acids(PUFAs), linoleic acid(LA), linolenic acid(ALA),and methyl jasmonate(Me Ja) were employed as the stimulant agents to coordinate the accumulation of biomass and hispidin polyphenols in its submerged cultures.Results: The addition of LA and ALA promoted the mycelial accumulation, while the addition of Me Ja inhibited the growth of S. vaninii concomitant with reduced total polyphenols. UPLC-Triple-TOF-MS analysis revealed an increased production of hispidin, phellinstatin, pinnilidine, and its derivatives upon the addition of LA and ALA, and hypholomine B and its isomer, 3,14’-bihispidinyl, and phelligridin E upon the addition of Me Ja on day 13. Intriguingly, total polyphenols from the Me Ja-supplementing cultures harbored a high capacity in scavenging free radicals. Chemical structural analysis showed that hispidin polyphenols had higher antioxidant activity due to more hispidin moieties induced by Me Ja.Conclusion: The supplement of PUFAs affects the synthesis and composition of hispidin polyphenols in S.vaninii. Our results provide a possibility to coordinate the production of hispidin polyphenols via submerged cultures of S. vaninii.