Linoleic acid and squalene are oxidized by discrete oxidation mechanisms in human sebum.

Previous studies suggest that squalene (SQ) in sebum is oxidized by a photooxidation mechanism (i.e., singlet oxygen oxidation) to create SQ hydroperoxide (SQOOH), a compound that causes adverse skin conditions. However, oxidation of other lipids in sebum, such as linoleic acid (LA), has not been fully understood. Elucidating their oxidation, especially its mechanisms, may lead to a further understanding of the relationship between sebum oxidation and skin conditions. In this study, using HPLC-MS/MS, we aimed to detect LA hydroperoxide (LAOOH) directly from sebum and identify the oxidation mechanism of LA in sebum through analysis of LAOOH isomers. We developed extraction and HPLC-MS/MS analysis conditions that can sufficiently quantify each LAOOH isomer in sebum. Using this method, LAOOH was detected in samples from healthy individuals, demonstrating the presence of LAOOH in human sebum. Moreover, isomer analysis of LAOOH and SQOOH indicated that LA and SQ are oxidized in sebum by discrete oxidation mechanisms (LA oxidized by free radical oxidation, whereas SQ oxidized by singlet oxygen oxidation). Such results may further lead to the development of mechanism-specific ways to prevent oxidation of sebum via a selection of appropriate antioxidants, ultimately leading to the promotion of skin health.

Comparative Study on Functional Components, Physicochemical Properties and Antioxidant Activity of Amaranthus Caudatus L. Oils Obtained by Different Solvents Extraction.

Functional compositions, physicochemical properties and antioxidant activities of Amaranthus caudatus L. oils (ACO) obtained by different solvents were comparatively investigated. All the resulted ACO were enrich in 75% unsaturated fatty acid and in squalene of about 4 g/100 g. Different solvents showed varying in oil extraction, where acetone results a highest yield of 6.80 g/100 g. ACO extracted by ethanol showed a highest tocopherol (1351.26 mg/kg), polyphenols (211.28 mg/kg) and squalene (42519.13 mg/kg). However, phytosterols in ACO extracted by hexane (27571.20 mg/kg) was higher than that by acetone (19789.91 mg/kg), ethanol (22015.73 mg/kg) and petroleum ether (24763.30 mg/kg). Furthermore, antioxidant activity of ACO was also measured by DPPH, ABTS and FRAP assay. According to principal component and correlation analysis, squalene was correlated with the DPPH scavenging ability, but phytosterols and tocopherols was correlated with the ABTS and ferric reducing ability of the oils, respectively. This study provides a promising excellent source of functional oil for food industries.

Co-production of DHA and squalene by thraustochytrid from forest biomass.

Omega-3 fatty acids, and specifically docosahexaenoic acid (DHA), are important and essential nutrients for human health. Thraustochytrids are recognised as commercial strains for nutraceuticals production, they are group of marine oleaginous microorganisms capable of co-synthesis of DHA and other valuable carotenoids in their cellular compartment. The present study sought to optimize DHA and squalene production by the thraustochytrid Schizochytrium limacinum SR21. The highest biomass yield (0.46 g/gsubstrate) and lipid productivity (0.239 g/gsubstrate) were observed with 60 g/L of glucose, following cultivation in a bioreactor, with the DHA content to be 67.76% w/wtotal lipids. To reduce costs, cheaper feedstocks and simultaneous production of various value-added products for pharmaceutical or energy use should be attempted. To this end, we replaced pure glucose with organosolv-pretreated spruce hydrolysate and assessed the simultaneous production of DHA and squalene from S. limacinum SR21. After the 72 h of cultivation period in bioreactor, the maximum DHA content was observed to 66.72% w/wtotal lipids that was corresponded to 10.15 g/L of DHA concentration. While the highest DHA productivity was 3.38 ± 0.27 g/L/d and squalene reached a total of 933.72 ± 6.53 mg/L (16.34 ± 1.81 mg/gCDW). In summary, we show that the co-production of DHA and squalene makes S. limacinum SR21 appropriate strain for commercial-scale production of nutraceuticals.

Tephrosia apollinea seed: a new rich source of essential polyunsaturated fatty acids, tocopherols, sterols, and squalene.

Tephrosia apollinea is a legume species, native to southwest Asia and northeast Africa, rich in bioactive flavonoids (hydrophilic compounds). T. apollinea seeds were not considered previously as a potential source of lipophilic compounds such as: essential fatty acids, tocopherols, sterols, and squalene, hence, the present study were performed. The oil yield in T. apollinea seeds amounted to 11.8% dw. The T. apollinea seed oil was predominated by the polyunsaturated fatty acids - linoleic (26.8%) and α-linolenic (22.7%). High levels were recorded also for oleic (27.6%) and palmitic (14.9%) acids. Four tocopherols and one tocotrienol, with the domination of γ-tocopherol (98%) were identified in T. apollinea seed oil. The ß-sitosterol (59%), Δ5-stigmasterol (21%) and campesterol (9%) were detected as main sterols in T. apollinea seed oil. The total content of tocochromanols, sterols, carotenoids and squalene in the T. apollinea seed oil was 256.7, 338.1, 12.5 and 1103.8 mg/100 g oil, respectively. T. apollinea seeds oil, due to the high concentration of lipophilic bioactive compounds can find a potential application in the food, cosmetic and pharmaceutical industry.

Evaluation of Oxasqualenoids from the Red Alga Laurencia viridis against Acanthamoeba.

Acanthamoeba genus is a widely distributed and opportunistic parasite with increasing importance worldwide as an emerging pathogen in the past decades. This protozoan has an active trophozoite stage, a cyst stage, and is dormant and very resistant. It can cause Acanthamoeba keratitis, an ocular sight-threatening disease, and granulomatous amoebic encephalitis, a chronic, very fatal brain pathology. In this study, the amoebicidal activity of sixteen Laurencia oxasqualenoid metabolites and semisynthetic derivatives were tested against Acanthamoeba castellanii Neff. The results obtained point out that iubol (3) and dehydrothyrsiferol (1) possess potent activities, with IC50 values of 5.30 and 12.83 µM, respectively. The hydroxylated congeners thyrsiferol (2) and 22-hydroxydehydrothyrsiferol (4), active in the same value range at IC50 13.97 and 17.00 µM, are not toxic against murine macrophages; thus, they are solid candidates for the development of new amoebicidal therapies.

Lipid Characteristics of Camellia Seed Oil.

Camellia oleifera, C. japonica and C. sinensis are three representative crops of the genus Camellia. In this work, we systematically investigated the lipid characteristics of these seed oils collected from different regions. The results indicated significant differences in acid value (AV), peroxide value (PV), iodine value (IV), saponification value (SV) and relative density of the above-mentioned camellia seed oils (p < 0.05). The C. japonica seed oils showed the highest AV (1.7 mg/g), and the C. sinensis seed oils showed the highest PV (17.4 meq/kg). The C. japonica seed oils showed the lowest IV (79.9 g/100 g), SV (192.7 mg/g) and refractive index (1.4633) of all the oils, while the C. sinensis seed oils showed the lowest relative density (0.911 g/cm3). The major fatty acids in the camellia seed oils were palmitic acid (16:0), oleic acid (18:1) and linoleic acid (18:2); the oleic acid in C. oleifera and C. japonica seed oils accounted for more than 80% of the total fatty acids. The oleic acid levels in the C. oleifera and C. japonica oils were higher than those in the C. sinensis seed oils, while the linoleic acid levels in the former were lower than those in the latter one. Differences also exist in the triacylglycerol (TAG) composition, although the most abundant TAG molecular species in the camellia seed oils was trioleoylglycerol (OOO). Seven sterol species, squalene and α-tocopherol were detected in the camellia seed oils, however, the contents of tocopherol and unsaponifiable molecules in the C. oleifera and C. japonica seed oils were significantly lower than those in the C. sinensis seed oil. These results demonstrated that the varieties of Camellia affected the seed oil lipid characteristics.

Studies on Squalene Biosynthesis and the Standardization of Its Extraction Methodology from Saccharomyces cerevisiae.

In this study, a homogenization-based extraction method was developed and was compared to five conventional methods of squalene extraction. Squalene recovered from this novel procedure gave 3.5-fold, 10-fold, 16-fold, and 8.1-fold higher yield than standard procedures, viz., saponification with 60% KOH, acidic saponification, saponification with 18% KOH, and glass beads method, respectively. Furthermore, this procedure has been evaluated on laboratory Saccharomyces cerevisiae strains such as BY4742 and CEN.PK2-1C (native), deletion strains (ERG6 and ERG11), and tHMG1 overexpressed S. cerevisiae strains. When sonication method of cell lysis was replaced with homogenization, it was found that the yields were significantly higher and reached a value of 9 mg/g DCW in case of BY4742. In addition, squalene yield in ergosterol mutant strains has been analyzed and was found to be 1.8-fold and 3.4-fold higher in ERG6 and ERG11 deletion strains, respectively, than in BY4742. Squalene was also found to be higher at the optimized temperature of 30 °C and pH 6.0. Furthermore, tolerance of S. cerevisiae to external squalene at various concentrations has been carried and found that the organism was tolerant up to 25 g/L of squalene.

Squalene Found in Alpine Grassland Soils under a Harsh Environment in the Tibetan Plateau, China.

Squalene is found in a large number of plants, animals, and microorganisms, as well as other sources, playing an important role as an intermediate in sterol biosynthesis. It is used widely in the food, cosmetics, and medicine industries because of its antioxidant, antistatic, and anti-carcinogenic properties. A higher natural squalene component of lipids is usually reported as being isolated to organisms living in harsh environments. In the Tibetan Plateau, which is characterized by high altitude, strong solar radiation, drought, low temperatures, and thin air, the squalene component was identified in five alpine grasslands soils using the pyrolysis gas chromatography⁻mass spectrometry (Py-GC/MS) technique. The relative abundance of squalene ranged from 0.93% to 10.66% in soils from the five alpine grasslands, with the highest value found in alpine desert and the lowest in alpine meadow. Furthermore, the relative abundance of squalene in alpine grassland soils was significantly negatively associated with soil chemical/microbial characteristics. These results indicate that the extreme environmental conditions of the Tibetan Plateau may stimulate the microbial biosynthesis of squalene, and the harsher the environment, the higher the relative abundance of soil squalene.

Medium's conductivity and stage of growth as crucial parameters for efficient hydrocarbon extraction by electric field from colonial micro-algae.

The green algae Botryococcus braunii produces a high amount of extracellular hydrocarbon, making it a promising algae in the field of bio-fuels production. As it mainly produces squalene like hydrocarbons, cosmetic industries are also interested in its milking. Pulsed electric fields (PEF) are an innovative method allowing oil extraction from micro-algae. In common algae accumulating hydrocarbon inside cytoplasm (Chlorella vulgaris, Nannochloropsis sp., etc), electric fields can destroy cell membranes, allowing the release of hydrocarbon. However, for B.braunii, hydrocarbons adhere to the cell wall outside of cells as a matrix. In a previous article we reported that electric fields can unstick cells from a matrix, allowing hydrocarbon harvesting. In this work, we deeper investigated this phenomenon of cell hatching by following 2 parameters: the conductivity of the medium and the cultivation duration of the culture. Cell hatching is accurately evaluated by both microscopic and macroscopic observations. For high conductivity and a short time of cultivation, almost no effect is observed even after up to 1000 PEF pulses are submitted to the cells. While lower conductivity and a longer cultivation period allow strong cell hatching after 200 PEF pulses are applied to the cells. We identify 2 new crucial parameters, able to turn the method from inefficient to very efficient. It might help companies to save energy and money in case of mass production.

Isolation and Characterization of Cyclic C33 Botryococcenes and a Trimethylsqualene Isomer from Botryococcus braunii Race B.

Three cyclic C33 botryococcenes and one new trimethylsqualene isomer were isolated from the B race, Showa (Berkeley) strain of Botryococcus braunii, which is known to produce large amounts of isoprenoid hydrocarbons ranging in carbon number from 30 to 34. Their purity was determined by GC-MS, and structures were characterized by 1D and 2D NMR. One of these molecules, cyclic C33-1 botryococcene (5), has an unusual connection of a methylenecyclohexane ring to the molecule backbone not seen before in botryococcenes. This report further adds to our knowledge of the wide range of isoprenoid hydrocarbon structures produced by B. braunii.

Biosynthetic Approaches to Squalene Production: The Case of Yeast.

Squalene is a precursor in the eukaryotic sterol biosynthesis. It is a valuable compound with several human health-related applications. Since the traditional natural resources of squalene are limited, alternatives for the production of squalene on industrial scale have been intensively explored during past years. The yeast Saccharomyces cerevisiae represents an attractive option due to elaborated techniques of genetic and metabolic engineering that can be applied to improve squalene yields. We discuss in this chapter some theoretical aspects of genetic manipulations of the ergosterol biosynthesis pathway aimed at increased squalene production and describe analytical methods for squalene purification and determination of its content in yeast cells.

Extraction methods of Amaranthus sp. grain oil isolation.

BACKGROUND: Amaranthus sp. is a fast-growing crop with well-known beneficial nutritional values (rich in protein, fat, dietary fiber, ash, and minerals, especially calcium and sodium, and containing a higher amount of lysine than conventional cereals). Amaranthus sp. is an underexploited plant source of squalene, a compound of high importance in the food, cosmetic and pharmaceutical industries. RESULTS: This paper has examined the effects of the different extraction methods (Soxhlet, supercritical fluid and accelerated solvent extraction) on the oil and squalene yield of three genotypes of Amaranthus sp. grain. The highest yield of the extracted oil (78.1 g kg(-1) ) and squalene (4.7 g kg(-1) ) in grain was obtained by accelerated solvent extraction (ASE) in genotype 16. Post hoc Tukey's HSD test at 95% confidence limit showed significant differences between observed samples. Principal component analysis (PCA) and cluster analysis (CA) were used for assessing the effect of different genotypes and extraction methods on oil and squalene yield, and also the fatty acid composition profile. Using coupled PCA and CA of observed samples, possible directions for improving the quality of product can be realized. CONCLUSION: The results of this study indicate that it is very important to choose both the right genotype and the right method of extraction for optimal oil and squalene yield. © 2015 Society of Chemical Industry.

Alp Rose stem cells, olive oil squalene and a natural alkyl polyglucoside emulsifier: Are they appropriate ingredients of skin moisturizers - in vivo efficacy on normal and sodium lauryl sulfate - irritated skin?.

Background/Aim: Since skin moisturization may be achieved by both actives and chosen carrier, plant stem cells, squalene and natural alkyl polyglucoside emulsifier may be potential components of contemporary cosmetic products. The aim of the study was in vivo evaluation of the skin irritation potential and the efficacy of Alpine Rose stem cells incorporated into li-posomes and olive oil squalene as ingredients of moisturizing creams, with respect to the novel emulsifier used for creams' stabilization. Methods: With the employment of noninvasive skin biophysical measurements, skin hydration (EC), transepi-dermal water loss (TEWL), erythema index (EI) and viscoelas-ticity were measured on 76 healthy volunteers. In the first phase, skin irritation after a 24-hour occlusion and the long-term efficacy of creams (a 21-day study) on healthy skin were evaluated. Phase II of the study focused on the cream efficacy assessment after a 6-day treatment of sodium lauryl sulfate-irritated skin. Results: After a 24-hour occlusion, there were no significant changes in the EI for any tested sample. In the second phase of the study, the EI was not significantly altered for the cream containing squalene, while the application of all active samples resulted in a significant reduction of TEWL. In both phases of the study an EC increase was recorded, espe-cially for the squalene-containing cream. Conclusion: Due to the lack of skin irritation and skin barrier impairment along with the marked hydration effect, it could be said that the in-vestigated actives incorporated into alkyl polyglucoside emulsi-fier-stabilized creams may be safely applied as ingredients for "tailor-made" cosmetic moisturizers intended for normal and dry skin care, whereas olive oil squalene could be used for the treatment of irritated or sensitive skin as well. [Projekat Ministarstva nauke Republike Srbije, br. TR34031]

Regulation of liver cell glucose homeostasis by dehydroabietic acid, abietic acid and squalene isolated from balsam fir (Abies balsamea (L.) Mill.) a plant of the Eastern James Bay Cree traditional pharmacopeia.

In our previous study, Abies balsamea (L.) Mill., a plant used in Cree traditional medicine, had a strong effect on the regulation of glucose homeostasis in liver cells. This study aimed to isolate and identify its active constituents using a bioassay-guided fractionation approach as well as to elucidate their mechanism(s) of action. The effect of the crude extract and its constituents was evaluated on the activity of Glucose-6-Phosphatase (G6Pase) and Glycogen Synthase (GS) and phosphorylation of three kinases, AMP-activated protein kinase (AMPK), Akt and Glycogen Synthase Kinase-3 (GSK-3). Three compounds, abietic acid, dehydroabietic acid and squalene, were isolated from the most active fraction in the bioassays (hexane). The compounds were able to decrease the activity of G6Pase and to stimulate GS. Their effect on G6Pase activity involved both Akt and AMPK phosphorylation with significant correlations between insulin-dependent and -independent pathways and the bioassay. In addition, the compounds were able to stimulate GS through GSK-3 phosphorylation with a significant correlation between the signaling pathway and the bioassay. Dehydroabietic acid stood out for its strongest effect in all the experiments close to that of the crude extract. These compounds may have potential applications in the treatment of type 2 diabetes and insulin resistance.

Insecticidal activity of Jatropha curcas extracts against housefly, Musca domestica.

The hexane and ether extracts of leaves, bark and roots of Jatropha curcas were screened for their toxicity against different developmental stages of housefly. The larvicidal, pupicidal and adulticidal activities were analysed at various concentrations (0.78-7.86 mg/cm(2)) of hexane and ether extracts. The lethal concentration values (LC50) of hexane extract of J. curcas leaves were 3.0 and 0.27 mg/cm(2) for adult and larval stages of housefly, respectively, after 48 h. Similarly, the ether extract of leaf showed the LC50 of 2.20 and 4.53 mg/cm(2) for adult and larval stages of housefly. Least toxicity was observed with hexane root extract of J. curcas with LC50 values of 14.18 and 14.26 mg/cm(2) for adult and larvae of housefly, respectively, after 48 h. The variation in LC50 against housefly pupae was found to be 8.88-13.10 mg/cm(2) at various J. curcas extract concentrations. The GC-MS analysis of J. curcas leaf extract revealed the presence of trans-phytol (60.81 %), squalene (28.58 %), phytol (2.52 %) and nonadecanone (1.06 %) as major components that could be attributed for insecticidal activity of J. curcas extracts.

Effect of agricultural sites on differentiation between Chemlali and Neb Jmel olive oils.

The chemical composition, oxidative stability, aroma and sensory profiles of virgin olive oils from two Tunisian cultivars, Chemlali and Neb Jmel, grown in two different locations, the center and south of Tunisia, have been evaluated. There were significant differences between the oils from both cultivars when grown in the two different environments. At higher altitude, the oils showed a greater amount of oleic acid, phenols and a higher oxidative stability, while at lower altitude, the oils had higher saturated and linoleic acid contents. The aroma profiles in Chemlali and Neb Jmel cultivars were also influenced by the pedoclimatic conditions, as shown by the difference in volatiles as a function of the geographical area. The volatile compounds of the monovarietal virgin olive oils were identified and compared using headspace solid-phase microextraction (HS-SPME) technique coupled with GC-MS and GC-FID. The proportions of different classes of volatiles of the oils have shown significant differences throughout the obtained oils. These results suggest that besides the genetic factor, the agronomic conditions affect the volatile formation and, therefore, the organoleptic properties of VOO, and can be used to discriminate and characterize the Chemlali and Neb Jmel olive oils from each region.

Chemical characterization and antioxidant activity of Amazonian (Ecuador) Caryodendron orinocense Karst. and Bactris gasipaes Kunth seed oils.

Nowadays, data concerning the composition of Caryodendron orinocense Karst. (Euphorbiaceae) and Bactris gasipaes Kunth (Arecaceae) seed oils are lacking. In light of this fact, in this paper fatty acids and unsaponifiable fraction composition have been determined using GC-MS, HPLC-DAD (Diode Array Detector), NMR approaches and possible future applications have been preliminary investigated through estimation of antioxidant activity, performed with DPPH test. For C. orinocense linoleic acid (85.59%) was the main component, lauric (33.29%) and myristic (27.76%) acids were instead the most abundant in B. gasipaes. C. orinocense unsaponifiable fraction (8.06%) evidenced a remarkable content of ß-sitosterol, campesterol, stigmasterol, squalene and vitamin E (816 ppm). B. gasipaes revealed instead ß-sitosterol and squalene as main constituents of unsaponifiable matter (3.01%). Antioxidant capacity evidenced the best performance of C. orinocense seed oil. These preliminary results could be interesting to suggest the improvement of the population's incomes from Amazonian basin. In particular the knowledge of chemical composition of C. orinocense and B. gasipaes oils could be helpful to divulge and valorize these autochthones plants.

[Study on chemical constituents from leaf of Bombax ceiba (II)].

OBJECTIVE: To study the chemical constituents from the leaf of Bombax ceiba. METHODS: The compounds were isolated and purified with silica gel and Sephadex LH-20 column chromatography. Their structures were determined on the basis of physicochemical properties and spectroscopic analysis. RESULTS: Eleven compounds were isolated and identified as taraxeryl acetate (1), squalene (2), taraxerone (3), beta-sitosterol palmitate (4), taraxerol (5), 4-methyl stigmast-7-en-3-ol (6), 1H-indole-3-carboxylic acid (7), 6-O-palmitoylsitosteryl-D-glucoside (8), 12beta-hydroxyl-pregnane-4, 16-diene-3, 20-dione (9), loliolide (10) and 5-(hydroxymethyl) furfural (11). CONCLUSION: All the compounds are isolated from this genus for the first time.

Isolation and biological evaluation of novel Tetracosahexaene hexamethyl, an acyclic triterpenoids derivatives and antioxidant from Justicia adhatoda.

Forty five extracts fraction of nine selected Indian medicinal plants, based on their use in traditional systems of medicine were analyzed for their antioxidant potential. All the extracts were investigated for phenol content value calculated in Gallic acid equivalents (% of GAE) and antioxidant potential. Moreover, total phenolic content (% dw equivalents to gallic acid) of all plant extracts were found in the range of 3.04 to 24.03, which correlated with antioxidant activity. The findings indicated a promising antioxidant activity of crude extracts fractions of three plants (Justicia adhatoda, Capparis aphylla and Aegle marmelos) and required the further exploration for their effective utilization. Results indicated that petroleum ether fraction of J. adhatoda out of three plants also possesses the admirable antioxidant abilities with high total phenolic content. Following, in vitro antioxidant activity-guided phytochemical separation procedures, twelve fractions of petroleum ether extract of J. adhatoda were isolated by silica gel column chromatography. One fraction (Rf value: 0.725) showed the noticeable antioxidant activity with ascorbic acid standard in hydroxyl radical scavenging assays. The molecular structures elucidations of purified antioxidant compound were carried out using spectroscopic studies ((1)H NMR, (13)C NMR and MS). This compound was reported from this species for the first time. The results imply that the J. adhatoda might be a potential source of natural antioxidants and 2,6,10,14,18,22-Tetracosahexaene, 2,6,10,15,19,23-hexamethyl is an antioxidant ingredient in J. adhatoda.

Extraction of squalene as value-added product from the residual biomass of Schizochytrium mangrovei PQ6 during biodiesel producing process.

Today microalgae represent a viable alternative source of squalene for commercial application. The species Schizochytrium mangrovei, a heterotrophic microalga, has been widely studied and provides a high amount of squalene, polyunsaturated fatty acids and has good profiles for biodiesel production. Our work was aimed at examining the squalene contents in Vietnam's heterotrophic marine microalga S. mangrovei PQ6 biomass and residues of the biodiesel process from this strain. Thin-layer chromatography and high-performance liquid chromatography (HPLC) methods were successfully applied to the determination of squalene in S. mangrovei PQ6. The squalene content and production of S. mangrovei PQ6 reached 33.00 ± 0.02 and 33.04 ± 0.03 mg g(-1) of dry cell weight; and 0.992 g L(-1) and 1.019 g L(-1) in 30 and 150 L bioreactors, respectively after 96 h of fermentation. In addition, squalene was also detected in spent biomass (approximately 80.10 ± 0.03 mg g(-1) of spent biomass) from the S. mangrovei PQ6 biodiesel production process. The structure of squalene in residues of the biodiesel process was confirmed from its nuclear magnetic resonance spectra. The results obtained from our work suggest that there is tremendous potential in the exploitation of squalene as a value-added by-product besides biodiesel from S. mangrovei PQ6 to reduce biodiesel price.