Methods for obtaining and determination of squalene from natural sources

MF59-like adjuvant containing yeast-derived squalene enhances the humoral immune response to cell-derived influenza vaccine

The aims of this study were to assess the adjuvant properties of an MF59-like adjuvant containing yeast-derived squalene (MF59-like YD) in a cell-based quadrivalent influenza vaccine (QIV) and to investigate the potential mechanisms of action. MF59-like adjuvants containing either yeast-derived or shark-derived squalene were incorporated into QIV formulations. Antigen-specific immune responses in mouse serum were evaluated via enzyme-linked immunosorbent assays (ELISAs), hemagglutination inhibition (HI) assays, and microneutralization (MN) assays. The effects and mechanisms of action of the adjuvants were further analyzed by analyzing mouse spleen germinal center (GC) cell activation via flow cytometry. MF59-like YD significantly increased the humoral immune responses induced by QIVs in mice, in particular, the titers of HI and MN antibodies against homologous and heterologous virus subtypes. Mechanistically, MF59-like YD increased the immune response to influenza vaccines by activating T follicular helper (Tfh) and B cells in the GC. Given the greater availability of yeast-derived squalene and the finding that its adjuvant efficacy was comparable to that of shark-derived squalene, we propose that the MF59-like YD adjuvant is a promising alternative adjuvant for future influenza vaccines.

Detection of Mycobacteria in Arabian camels and antimycobacterial potential of Moringa oleifera

The World Health Organization gave great attention to Mycobacterium tuberculosis, especially its zoonotic impact. Dromedary camels in Arabian countries are of great importance, as well as awareness of production and health. Little was known about the occurrence of M. tuberculosis among Arabian camels. Out of 88 samples were collected from necropsied male camels aged 5-6.5 years after the slaughter process resident in Cairo abattoir. Isolation of Mycobacteria was achieved on Middle Brook 7H10 agar with special supplements, and then the suspected colonies were assessed by their specific aspects. Lungs and lymph nodes were processed for histopathology. Molecular characterization was carried out by both conventional amplification (Mycobacterium bovis mpb70, M. tuberculosis- Pan Mycobacterium 16S rRNA) tracked by sanger sequencing; and bacterial 16S rRNA V3-V4 hypervariable region was amplified then it was followed by Mi-seq Ilumina. Moringa oliefera's oil was analyzed by GC-MS. The antimycobacterial potential of M. oliefera was conducted by In vitro tetrazolium microplate assay (TEMA). In silico docking mode of action and prediction were studied. Mycobacterium was isolated from 9.4% (3/32) of the lung samples and 2.4% (1/41) of the recovered lymph node samples. The isolated strains had ideal culture characteristics of Mycobacterium. Sanger sequencing identified the M. tuberculosis variant bovis DRC-EG-CAMEL PQ036932. Mi-seq Illumina revealed abundant sequence readings belonging to ancestral Actinobacteria and Micromonosporaceae. In vitro testing showed that the Moringa oleifera methanol leaf extract had antimicrobial activity with MIC ranging from 7.8 to 32 µg/ml, and the seed oil showed inhibitory effects at 50% (v/v) (P value < 0.05). In silico docking of ferulic acid against M. tuberculosis variant bovis ribosomal protein S1 showed an affinity score of - 5.95 kcal/mol with one hydrogen bond. While squalene lipoprotein LprF exhibited a professional affinity score of - 6.11 kcal/mol with seventeen hydrophobic π-interactions. Mycobacterium tuberculosis variant bovis is measured to prevail in the Arabian camels. However, this study provided a detailed examination of Mycobacterium in camels, offering practical solutions to combat this pathogen and mitigate the effects of infection or zoonotic impacts on other animals and humans. Sanger sequencing is more recommended for Mycobacterium identification. Moringa oliefera's potential anti-mycobacterial effect through either leaves or oil might be achieved for humans and animals as a different strategy for medicinal plants' role. It might be a new insight into the struggle and the adverse effects of tuberculosis. In the upcoming research, therapeutic compounds could be separated from M. oliefera.

Therapeutic potential of thymoquinone in regulating p63, claudin, and periostin in chronic rhinosinusitis with nasal polyps: An animal model study

High recurrence rate and the necessity for repeated surgical interventions contribute to the chronicity and treatment-resistant nature of chronic rhinosinusitis with nasal polyps (CRSwNP). Thymoquinone, known for its protective effects on epithelial integrity, has not been previously explored in CRSwNP. The aim of this study was to investigate the therapeutic potential of thymoquinone to restore epithelial integrity by assessing p63 transcription factor and claudin protein expressions, as well as periostin mRNA expression in an animal model. An in vivo study using post-test-only control group design was conducted in which male Wistar rats were randomly assigned to three groups, each consisting of 10 animals: healthy group, CRSwNP group, and thymoquinone-treated group for three weeks. Immunohistochemistry was used to analyze the p63 and claudin protein expressions, while periostin mRNA expression was quantified using quantitative reverse transcription polymerase chain reaction (qRT-PCR). This study found that thymoquinone significantly reduced p63 transcription factor expression compared to the untreated CRSwNP group (p = 0.009). Claudin protein expression was significantly higher in thymoquinone-treated group compared to CRSwNP group (p = 0.007), indicating improved epithelial barrier function. Periostin mRNA expression showed no significant difference between healthy and thymoquinone-treated groups (p = 0.564), but a significant decrease was observed in CRSwNP group compared to thymoquinone-treated group (p = 0.000) and between the healthy and CRSwNP groups (p = 0.002), suggesting attenuation of tissue remodeling and inflammation. In conclusion, thymoquinone could enhance sinonasal epithelial barrier integrity in CRSwNP by downregulating p63 transcription factor, upregulating claudin protein expression, and reducing periostin mRNA expression. These findings emphasize the potential of thymoquinone as a therapeutic agent to mitigate inflammation and tissue remodeling in CRSwNP, warranting further investigation as a novel treatment option.

Molecular Profiling and FTIR Characterization of Wheat Germ Oil, Supported by the Screening of Its Anti-Inflammatory and Cytotoxic Properties

Wheat germ oil (WGO), derived from the nutrient-dense germ of wheat kernels, is a functional bioactive product, known for its rich composition of essential fatty acids, sterols, tocopherols, and polyphenols. This study aimed to comprehensively profile the molecular and therapeutic properties of WGO, focusing on its antioxidant, cytotoxic, and anti-inflammatory activity. Using advanced analytical techniques such as gas chromatography-mass spectrometry (GC-MS), Fourier Transform Infrared (FTIR) spectroscopy, and fluorescence analysis, WGO was shown to contain high levels of linoleic acid (45.3%), squalene (2.52 g/100 g), and polyphenols. WGO displayed selective cytotoxicity, inhibiting cancer cells' viability in melanoma, prostate, and colorectal cancer cell lines, but not normal cells, highlighting its chemoprevention potential. Furthermore, WGO significantly reduced LPS-induced nitric oxide and IL-6 production in macrophages, with effects plateauing at higher doses. The 3D fluorescence spectra showed a significant decrease in fluorescence intensity when human serum albumin interacted with the WGO polyphenol fraction, indicating a strong binding affinity and stable complex formation. These findings emphasize the nutritional and therapeutic potential of WGO as a natural bioactive agent, warranting further mechanistic investigation and broader applications in health and disease management.

Changes in key volatile components associated with leaf quality of Pandanus amaryllifolius Roxb. alongside growth duration

Pandan (Pandanus amaryllifolius Roxb.) are one of the traditional food materials in Southeast Asian countries. However, there has long been a lack of understanding of the differences in volatile organic compounds (VOCs) of leaves at different growth periods. Gas chromatography-mass spectrometry (GC-MS) was used to identify and analyze VOCs in different leaf positions of Pandan in this study. The content of 2-Acetyl-1-pyrroline (2AP) was higher in L1-L3 and decreased with leaf growth, while squalene showed the opposite trend. The content of neophytadiene first increased and then decreased, reaching the highest in L15. L8 is the critical point at which the content of each major VOCs is balanced. Combining agronomic traits and VOCs content, leaves in L4-L25 position are suitable for harvesting. This study provides data support for scientific judgment of the harvesting site and time of Pandan, and provides theoretical basis for further utilization of VOCs of Pandan.

Metabolic Engineering for Squalene Production: Advances and Perspectives

Squalene is a linear polyunsaturated triterpene which has multiple physiological functions including anticancer, antioxidant, and skin-care. It has been widely used in the food, medicine, and cosmetics sectors and also serves as a precursor of triterpenes and steroids. Recently, the production of squalene by microbial cell hosts has drawn much attention due to its sustainability, environmental friendliness, and great efficiency. In this review, we first introduce the recent developments in the production of squalene by employing microbial cell factories, especially yeasts. Next, we underscore the primary metabolic strategies, including the biosynthetic pathway engineering, precursor manipulation, cofactor engineering, and organelle engineering. In addition to traditional metabolic engineering strategies, we also discuss some prospective metabolic regulation approaches, including regulation of lipid synthesis, identifying and manipulating related transcription factors, dynamic regulation of the metabolic pathway, and secretion engineering of membrane-impermeable terpenoids. These approaches provide insights for further metabolic engineering of squalene and related terpenoids.

Analytical Determination of Squalene in Extra Virgin Olive Oil and Olive Processing By-Products, and Its Valorization as an Ingredient in Functional Food-A Critical Review

Squalene is a bioactive compound with significant health benefits, predominantly found in extra virgin olive oil (EVOO) and its processing by-products. This critical review explores the analytical determination of squalene in EVOO and various by-products from olive oil production, highlighting its potential as a valuable ingredient in functional foods. An overview of existing analytical methods is provided, focusing on different approaches to sample preparation before analytical determination, evaluating their effectiveness in quantifying squalene concentrations. Studies not primarily centered on analytical methodologies or squalene quantification were excluded. A critical gap identified is the absence of an official method for squalene determination, which hinders comparability and standardization across studies, underscoring the importance of developing a reliable, standardized method to ensure accurate quantification. The valorization of squalene involves advocating for its extraction from olive oil processing by-products to enhance sustainability in the olive oil industry. By recovering squalene, the industry can not only reduce waste but also enhance functional food products with this health-promoting compound. Additionally, there is a need for economically sustainable and environmentally friendly extraction techniques that can be scaled up for industrial application, thus contributing to a circular economy within the olive oil sector.

Diverse uses of valuable seafood processing industry waste for sustainability: a review

Seafoods are rich in untapped bioactive compounds that have the potential to provide novel ingredients for the development of commercial functional foods and pharmaceuticals. Unfortunately, a large portion of waste or discards is generated in commercial processing setups (50-80%), which is wasted or underutilized. These by-products are a rich source of novel and valuable biomolecules, including bioactive peptides, collagen and gelatin, oligosaccharides, fatty acids, enzymes, calcium, water-soluble minerals, vitamins, carotenoids, chitin, chitosan and biopolymers. These fish components may be used in the food, cosmetic, pharmaceutical, environmental, biomedical and other industries. Furthermore, they provide a viable source for the production of biofuels. As a result, the current review emphasizes the importance of effective by-product and discard reduction techniques that can provide practical and profitable solutions. Recognizing this, many initiatives have been initiated to effectively use them and generate income for the long-term sustainability of the environment and economic framework of the processing industry. This comprehensive review summarizes the current state of the art in the sustainable valorisation of seafood by-products for human consumption. The review can generate a better understanding of the techniques for seafood waste valorisation to accelerate the sector while providing significant benefits.

Microbial Squalene: A Sustainable Alternative for the Cosmetics and Pharmaceutical Industry - A Review

Squalene is a natural triterpenoid and a biosynthetic precursor of steroids and hopanoids in microorganisms, plants, humans, and other animals. Squalene has exceptional properties, such as its antioxidant activity, a high penetrability of the skin, and the ability to trigger the immune system, promoting its application in the cosmetic, sustenance, and pharmaceutical industries. Because sharks are the primary source of squalene, there is a need to identify low-cost, environment friendly, and sustainable alternatives for producing squalene commercially. This shift has prompted scientists to apply biotechnological advances to research microorganisms for synthesizing squalene. This review summarizes recent metabolic and bioprocess engineering strategies in various microorganisms for the biotechnological production of this valuable molecule.

Engineered poplar for bioproduction of the triterpene squalene

Building sustainable platforms to produce biofuels and specialty chemicals has become an increasingly important strategy to supplement and replace fossil fuels and petrochemical-derived products. Terpenoids are the most diverse class of natural products that have many commercial roles as specialty chemicals. Poplar is a fast growing, biomassdense bioenergy crop with many species known to produce large amounts of the hemiterpene isoprene, suggesting an inherent capacity to produce significant quantities of other terpenes. Here we aimed to engineer poplar with optimized pathways to produce squalene, a triterpene commonly used in cosmetic oils, a potential biofuel candidate, and the precursor to the further diversified classes of triterpenoids and sterols. The squalene production pathways were either re-targeted from the cytosol to plastids or co-produced with lipid droplets in the cytosol. Squalene and lipid droplet co-production appeared to be toxic, which we hypothesize to be due to disruption of adventitious root formation, suggesting a need for tissue specific production. Plastidial squalene production enabled up to 0.63 mg/g fresh weight in leaf tissue, which also resulted in reductions in isoprene emission and photosynthesis. These results were also studied through a technoeconomic analysis, providing further insight into developing poplar as a production host.

Tailored UPRE2 variants for dynamic gene regulation in yeast

Genetic elements are foundational in synthetic biology serving as vital building blocks. They enable programming host cells for efficient production of valuable chemicals and recombinant proteins. The unfolded protein response (UPR) is a stress pathway in which the transcription factor Hac1 interacts with the upstream unfolded protein response element (UPRE) of the promoter to restore endoplasmic reticulum (ER) homeostasis. Here, we created a UPRE2 mutant (UPRE2m) library. Several rounds of screening identified many elements with enhanced responsiveness and a wider dynamic range. The most active element m84 displayed a response activity 3.72 times higher than the native UPRE2. These potent elements are versatile and compatible with various promoters. Overexpression of HAC1 enhanced stress signal transduction, expanding the signal output range of UPRE2m. Through molecular modeling and site-directed mutagenesis, we pinpointed the DNA-binding residue Lys60 in Hac1(Hac1-K60). We also confirmed that UPRE2m exhibited a higher binding affinity to Hac1. This shed light on the mechanism underlying the Hac1-UPRE2m interaction. Importantly, applying UPRE2m for target gene regulation effectively increased both recombinant protein production and natural product synthesis. These genetic elements provide valuable tools for dynamically regulating gene expression in yeast cell factories.

A Novel Method for the Determination of Squalene, Cholesterol and Their Oxidation Products in Food of Animal Origin by GC-TOF/MS

Cholesterol present in food of animal origin is a precursor of oxysterols (COPs), whose high intake through diet can be associated with health implications. Evaluation of the content of these contaminants in food is associated with many analytical problems. This work presents a GC-TOF/MS method for the simultaneous determination of squalene, cholesterol and seven COPs (7-ketocholesterol, 7α-hydroxycholesterol, 7β-hydroxycholesterol, 25-hydroxycholesterol, 5,6α-epoxycholesterol, 5,6β-epoxycholesterol, cholestanetriol). The sample preparation procedure includes such steps as saponification, extraction and silylation. The method is characterized by high sensitivity (limit of quantification, 0.02-0.25 ng mL-1 for instrument, 30-375 μg kg of sample), repeatability (RSD 2.3-6.2%) and a wide linearity range for each tested compound. The method has been tested on eight different animal-origin products. The COP to cholesterol content ratio in most products is about 1%, but the profile of cholesterol derivatives differs widely (α = 0.01). In all the samples, 7-ketocholesterol is the dominant oxysterol, accounting for 31-67% of the total COPs level. The levels of the other COPs range between 0% and 21%. In none of the examined products are cholestanetriol and 25-hydroxycholesterol present. The amount of squalene, which potentially may inhibit the formation of COPs in food, ranges from 2 to 57 mg kg-1.

Non-targeted discovery of high-value bio-products in Nicotiana glauca L: a potential renewable plant feedstock

The evaluation of plant-based feedstocks is an important aspect of biorefining. Nicotiana glauca is a solanaceous, non-food crop that produces large amounts of biomass and is well adapted to grow in suboptimal conditions. In the present article, compatible sequential solvent extractions were applied to N. glauca leaves to enable the generation of enriched extracts containing higher metabolite content comparing to direct leaf extracts. Typically, between 60 to 100 metabolite components were identified within the fractions. The occurrence of plant fatty acids, fatty acid alcohols, alkanes, sterols and terpenoids was detected by gas liquid chromatography-mass spectrometry (GC-MS) and metabolite identification was confirmed by comparison of physico-chemical properties displayed by available authentic standards. Collectively, co-products such waxes, oils, fermentable sugars, and terpenoids were all identified and quantified. The enriched fractions of N. glauca revealed a high level of readily extractable hydrocarbons, oils and high value co-products. In addition, the saccharification yield and cell wall composition analyses in the stems revealed the potential of the residue material as a promising lignocellulosic substrate for the production of fermentable sugars. In conclusion a multifractional cascade for valuable compounds/commodities has been development, that uses N. glauca biomass. These data have enabled the evaluation of N. glauca material as a potential feedstock for biorefining.

A quality by design framework for developing nanocrystal bioenabling formulations

The present study aims to outline a rational framework for the design and development of a 1.0% (w/v) hydrocortisone nanocrystal-based formulation, resorting to a simple, efficient, and scalable nanonization methodology, based on the high-pressure homogenization (HPH) technique. Accordingly, the innovative product was comprehensively optimized following a Quality by Design (QbD) approach. The thorough selection of formulation composition was driven by a dual purpose: improving skin permeation and stability. In the early stage of development, a Failure Mode, Effects and Criticality Analysis (FMECA) diagram was employed to identify the most impactful variables for the critical quality attributes (CQAs). In this sense, a rotatable, three-factor and five-level circumscribed central composite design (CCCD) was applied to investigate how squalene concentration (x1), soluplus concentration (x2) and HPH-time (x3) influence physicochemical properties, performance and physical stability of the formulation. A robust Design Space (DS) was defined, establishing the optimal settings for the critical variables, whose combination meets the requirements set in the quality target product profile (QTPP). Morphological analysis revealed the cuboidal shape of hydrocortisone nanocrystals. In what concerns colloidal properties, the most promising formulation disclosed a small particle size (Dx(50) = 311.8 ± 1.5 nm), along with narrow size distribution (span value = 1.91 ± 0.17). Zeta potential results (-2.19 ± 0.15 mV--12.1 ± 0.4 mV) suggested a steric hindrance stabilization. FTIR spectra showed no chemical interactions between drug and formulation components. XRD diffractograms confirmed loss of crystallinity during the downsizing process. In vitro studies revealed an improvement on drug release rate (316 ± 21-516 ± 35 μg/cm2/√t), compared to the coarse suspension and commercial products, and a straight dependence on the stabilizer concentration and HPH time. The permeation flux across the skin (0.16 ± 0.02-1.2 ± 0.5 μg/cm2/h) appeared to be dependent on the drug physicochemical properties, in particular saturation solubility. Further characterization of the experimental formulations pointed out the role of the stabilizing component to prevent against physical instability phenomena. This organic solvent-free, and therefore "green" nanocrystal production technology offers great potential for pharmaceutical R&D and drug delivery by enabling the development of new forms of conventional drugs with optimal physicochemical properties and performance.

Particulate organic emissions from incense-burning smoke: Chemical compositions and emission characteristics

Incense burning is a common practice in Asian cultures, releasing hazardous particulate organics. Inhaling incense smoke can result in adverse health effects, yet the molecular compositions of incense-burning organics have not been well investigated due to the lack of measurement of intermediate-volatility and semi-volatile organic compounds (I/SVOCs). To elucidate the detailed emission profile of incense-burning particles, we conducted a non-target measurement of organics emitted from incense combustion. Quartz filters were utilized to trap particles, and organics were analyzed by a comprehensive two-dimensional gas chromatography-mass spectrometer (GC × GC-MS) coupled with a thermal desorption system (TDS). To deal with the complex data obtained by GC × GC-MS, homologs are identified mainly by the combination of selected ion chromatograms (SICs) and retention indexes. SICs of 58, 60, 74, 91, and 97 were utilized to identify 2-ketones, acids, fatty acid methyl esters, fatty acid phenylmethyl esters, and alcohols, respectively. Phenolic compounds contribute the most to emission factors (EFs) among all chemical classes, taking up 24.5 % ± 6.5 % of the total EF (96.1 ± 43.1 μg g-1). These compounds are largely derived from the thermal degradation of lignin. Biomarkers like sugars (mainly levoglucosan), hopanes, and sterols are extensively detected in incense combustion fumes. Incense materials play a more important role in shaping emission profiles than incense forms. Our study provides a detailed emission profile of particulate organics emitted from incense burning across the full-volatility range, which can be used in the health risk assessments. The data processing procedure in this work could also benefit those with less experience in non-target analysis, especially GC × GC-MS data processing.

Screening of Oligomeric (Meth)acrylate Vaccine Adjuvants Synthesized via Catalytic Chain Transfer Polymerization

This report details the first systematic screening of free-radical-produced methacrylate oligomer reaction mixtures as alternative vaccine adjuvant components to replace the current benchmark compound squalene, which is unsustainably sourced from shark livers. Homo-/co-oligomer mixtures of methyl, butyl, lauryl, and stearyl methacrylate were successfully synthesized using catalytic chain transfer control, where the use of microwave heating was shown to promote propagation over chain transfer. Controlling the mixture material properties allowed the correct viscosity to be achieved, enabling the mixtures to be effectively used in vaccine formulations. Emulsions of selected oligomers stimulated comparable cytokine levels to squalene emulsion when incubated with human whole blood and elicited an antigen-specific cellular immune response when administered with an inactivated influenza vaccine, indicating the potential utility of the compounds as vaccine adjuvant components. Furthermore, the oligomers' molecular sizes were demonstrated to be large enough to enable greater emulsion stability than squalene, especially at high temperatures, but are predicted to be small enough to allow for rapid clearance from the body.

Effects of aluminum-salt, CpG and emulsion adjuvants on the stability and immunogenicity of a virus-like particle displaying the SARS-CoV-2 receptor-binding domain (RBD)

Second-generation COVID-19 vaccines with improved immunogenicity (e.g., breadth, duration) and availability (e.g., lower costs, refrigerator stable) are needed to enhance global coverage. In this work, we formulated a clinical-stage SARS-CoV-2 receptor-binding domain (RBD) virus-like particle (VLP) vaccine candidate (IVX-411) with widely available adjuvants. Specifically, we assessed the in vitro storage stability and in vivo mouse immunogenicity of IVX-411 formulated with aluminum-salt adjuvants (Alhydrogel™, AH and Adjuphos™, AP), without or with the TLR-9 agonist CpG-1018™ (CpG), and compared these profiles to IVX-411 adjuvanted with an oil-in-water nano-emulsion (AddaVax™, AV). Although IVX-411 bound both AH and AP, lower binding strength of antigen to AP was observed by Langmuir binding isotherms. Interestingly, AH- and AP-adsorbed IVX-411 had similar storage stability profiles as measured by antigen-binding assays (competitive ELISAs), but the latter displayed higher pseudovirus neutralizing titers (pNT) in mice, at levels comparable to titers elicited by AV-adjuvanted IVX-411. CpG addition to alum (AP or AH) resulted in a marginal trend of improved pNTs in stressed samples only, yet did not impact the storage stability profiles of IVX-411. In contrast, previous work with AH-formulations of a monomeric RBD antigen showed greatly improved immunogenicity and decreased stability upon CpG addition to alum. At elevated temperatures (25, 37°C), IVX-411 formulated with AH or AP displayed decreased in vitro stability compared to AV-formulated IVX-411and this rank-ordering correlated with in vivo performance (mouse pNT values). This case study highlights the importance of characterizing antigen-adjuvant interactions to develop low cost, aluminum-salt adjuvanted recombinant subunit vaccine candidates.

Bioprocess conditions and regulation factors to optimize squalene production in thraustochytrids

Squalene is a widely distributed natural triterpene, as it is a key precursor in the biosynthesis of all sterols. It is a compound of high commercial value worldwide because it has nutritional, medicinal, pharmaceutical, and cosmetic applications, due to its different biological properties. The main source of extraction has been shark liver oil, which is currently unviable on a larger scale due to the impacts of overexploitation. Secondary sources are mainly vegetable oils, although a limited one, as they allow low productive yields. Due to the diversity of applications that squalene presents and its growing demand, there is an increasing interest in identifying sustainable sources of extraction. Wild species of thraustochytrids, which are heterotrophic protists, have been identified to have the highest squalene content compared to bacteria, yeasts, microalgae, and vegetable sources. Several studies have been carried out to identify the bioprocess conditions and regulation factors, such as the use of eustressors that promote an increase in the production of this triterpene; however, studies focused on optimizing their productive yields are still in its infancy. This review includes the current trends that also comprises the advances in genetic regulations in these microorganisms, with a view to identify the culture conditions that have been favorable in increasing the production of squalene, and the influences that both bioprocess conditions and applied regulation factors partake at a metabolic level.

Analysis of Antidiabetic Activity of Squalene via In Silico and In Vivo Assay

Squalene has been tested widely in pharmacological activity including anticancer, antiinflammatory, antioxidant, and antidiabetic properties. This study aims to examine antidiabetic activity of squalene in silico and in vivo models. In the in silico model, the PASS server was used to evaluate squalene antidiabetic properties. Meanwhile, the in vivo model was conducted on a Type 2 Diabetes Mellitus (T2DM) with the rats separated into three groups. These include squalene (160 mg/kgbw), metformin (45 mg/kgbw), and diabetic control (DC) (aquades 10 mL/kgbw) administered once daily for 14 days. Fasting Blood Glucose Level (FBGL), Dipeptidyl Peptidase IV (DPPIV), leptin, and Superoxide Dismutase (SOD) activity were measured to analysis antidiabetic and antioxidant activity. Additionally, the pancreas was analysed through histopathology to examine the islet cell. The results showed that in silico analysis supported squalene antidiabetic potential. In vivo experiment demonstrated that squalene decreased FBGL levels to 134.40 ± 16.95 mg/dL. The highest DPPIV level was in diabetic control- (61.26 ± 15.06 ng/mL), while squalene group showed the lowest level (44.09 ± 5.29 ng/mL). Both metformin and squalene groups showed minor pancreatic rupture on histopathology. Leptin levels were significantly higher (p < 0.05) in diabetic control group (15.39 ± 1.77 ng/mL) than both squalene- (13.86 ± 0.47 ng/mL) and metformin-treated groups (9.22 ± 0.84 ng/mL). SOD activity were higher in both squalene- and metformin-treated group, particularly 22.42 ± 0.27 U/mL and 22.81 ± 0.08 U/mL than in diabetic control (21.88 ± 0.97 U/mL). In conclusion, in silico and in vivo experiments provide evidence of squalene antidiabetic and antioxidant properties.

Candida glycerinogenes-Promoted α-Pinene and Squalene Co-production Strategy Based on α-Pinene Stress

α-Pinene is a naturally occurring monoterpene, which is widely used in fragrances, cosmetics, and foods. Due to the high cellular toxicity of α-pinene, this work considered the application of Candida glycerinogenes, an effective industrial strain with high resistance, in α-pinene synthesis. It was found that α-pinene-induced stress resulted in an intracellular accumulation of reactive oxygen species with an increased formation of squalene as a cytoprotective compound. As squalene is a downstream product in the mevalonate (MVA) pathway for α-pinene synthesis, a strategy based on the promotion of α-pinene and squalene co-production under α-pinene stress is proposed. By introducing the α-pinene synthesis pathway and enhancing the MVA pathway, the production of both α-pinene and squalene is increased. We have demonstrated that intracellular synthesis of α-pinene is effective in promoting squalene synthesis. The generation of intercellular reactive oxygen that accompanies α-pinene synthesis promotes squalene synthesis with a resultant cellular protection and upregulation of MVA pathway genes that facilitate α-pinene production. In addition, we have overexpressed phosphatase and introduced NPP as a substrate to synthesize α-pinene, where co-dependent fermentation yielded 208 mg/L squalene and 12.8 mg/L α-pinene. This work establishes a viable strategy to promote terpene-co-dependent fermentation based on stress.

Exploiting the anaerobic fermentation of alfalfa as a renewable source of squalene

BACKGROUND

The use of alfalfa is a promising response to the increasing demand for squalene. Ensiling could enhance the squalene content of fresh alfalfa and silage. To investigate and exploit the anaerobic fermentation of forage as a new squalene source, alfalfa was ensiled without (CON) or with molasses (ML) and sunflower seed oil (SSL) for 10, 40, and 70 days.

RESULTS

Naturally ensiled alfalfa was of poor quality but had up to 1.93 times higher squalene content (P < 0.001) than fresh alfalfa. The squalene-producing bacteria were found to be cocci lactic acid bacteria (LAB). Adding ML and SSL decreased squalene content (P = 0.002 and P < 0.001) by 6.89% and 11.6%, respectively. Multiple linear regression models and correlation analysis indicated that squalene synthase was the key enzyme for squalene synthesis. The addition of ML and SSL altered the structure of LAB communities, mainly decreasing the relative abundance of cocci LAB, which was responsible for squalene synthesis, and changing the fermentation products (lactic acid, propionic acid, and ammonia-N) influencing the squalene-related enzymes, thereby decreasing squalene production. Compared with squalene production from the reference bacteria (Pediococcus acidilactici Ch-2, Rhodopseudomonas palustris, Bacillus subtilis, engineered Escherichia coli), alfalfa silage had the potential to be a new squalene source.

CONCLUSION

Natural ensiled alfalfa was a promising source for squalene, and ensiling was a potential pathway to obtain novel high-yield squalene bacteria. © 2022 Society of Chemical Industry.

Cleaner lipid processing: Supercritical carbon dioxide (Sc-CO2) and short path distillation

Today, regulations and consumer awareness demand production technologies with minimum impact on the environment and maximum utilization of available resources. In the field of lipids, two well-known technologies for avoiding the use of organic solvents and chemicals stand out: supercritical (Sc) fluids and short path distillation (SPD). To date, both technologies involve high operating costs that have limited their application to selected high value-added products which are high temperature sensitive. However, improvements in process control and materials make further implementation of these techniques possible. In this chapter, an integrative review has been carried out with the aim of compiling the literature on the application of these technologies to lipid extraction, micronization and fractionation of liquid mixtures. Special attention has been paid to the separation of compounds by both technologies: deacidification, partial purification of acylglycerol compounds, isolation of unsaponifiable compounds and separation of toxic and polluting compounds.

Development and Efficacy Evaluation of a Novel Nano-Emulsion Adjuvant for a Foot-and-Mouth Disease Virus-like Particles Vaccine Based on Squalane

The successful development of foot-and-mouth disease virus-like particles (FMD-VLPs) has opened a new direction for researching a novel subunit vaccine for foot-and-mouth disease (FMD). Therefore, it is urgent to develop an adjuvant that is highly effective and safe to facilitate a better immune response to be pair with the FMD-VLP vaccine. In this research, we prepared a new nano-emulsion adjuvant based on squalane (SNA) containing CpG using the pseudo-ternary phase diagram method and the phase transformation method. The SNA consisted of Span85, Tween60, squalane, polyethene glycol-400 (PEG400) and CpG aqueous solution. The average particle diameter of the SNA was about 95 nm, and it exhibited good resistance to centrifugation, thermal stability, and biocompatibility. Then, SNA was emulsified as an adjuvant to prepare foot-and-mouth disease virus-like particles vaccine, BALB/c mice and guinea pigs were immunized, and we evaluated the immunization effect. The immunization results in mice showed that the SNA-VLPs vaccine significantly increased specific antibody levels in mice within 4 weeks, including higher levels of IgG1 and IgG2a. In addition, it increased the levels of IFN-γ and IL-1β in the immune serum of mice. Meanwhile, guinea pig-specific and neutralizing antibodies were considerably increased within 4 weeks when SNA was used as an adjuvant, thereby facilitating the proliferation of splenic lymphocytes. More importantly, in guinea pigs immunized with one dose of SNA-VLPs, challenged with FMDV 28 days after immunization, the protection rate can reach 83.3%, which is as high as in the ISA-206 control group. In conclusion, the novel squalane nano-emulsion adjuvant is an effective adjuvant for the FMD-VLPs vaccine, indicating a promising adjuvant for the future development of a novel FMD-VLPs vaccine.

Using Compound-Specific Carbon Stable Isotope Analysis of Squalene to Establish Provenance and Ensure Sustainability for the Deep-Water Shark Liver Oil Industry

Deep-water dogfish (sharks) are caught on Australia’s continental shelf as by-products to other deep-water species with revenue derived from fillets for human consumption and from the livers which are sold for their oil content. Deep-water dogfish utilise a large oil-rich liver for buoyancy, which may account for 20–25% of their body weight. An important constituent of certain dogfish liver oil is squalene, a highly unsaturated triterpenoid (C30H50) hydrocarbon which in some species can be up to 90% of the oil, though in the Australian commercial species it is typically around 50%. Squalene (and deep-water dogfish liver oil in general) has a long-standing high value in products, such as cosmetics and nutraceuticals. Manufacturers are increasingly required to demonstrate the sustainability of products, and this is integral to the importance of demonstrating product provenance. Australia’s mid-slope deep-water dogfish fishery is recognised globally as well managed and sustainable; therefore, it is important to be able to distinguish products derived from these regions from other unregulated, unsustainable and cheaper sources in order to protect Australia’s competitive advantages and ensure sustainability. In this study, we have sourced deep-water dogfish liver oil samples originating from Southeast Australia, New Zealand, India, Northeast Africa and the Arabian Sea. The squalene was isolated by commercial or laboratory processing. A compound-specific carbon stable isotope analysis of the derived squalene was then used to determine isotopic resolution and assign the likely origins of a variety of commonly available off-the-shelf nutraceuticals in Australian outlets. Squalene sourced and produced from Southeast Australian and New Zealand dogfish liver oils showed δ13C values in the range of −22.1 to −24.2‰, with all other squalene samples distinguishable at −19.9 to −20.7‰. Many of the off-the-shelf squalene products claiming to be of Australian origin showed δ13C values very distinct from the range of the genuine Southeast Australian- and New Zealand-produced squalene.

Amaranth Oilseed Composition and Cosmetic Applications

Amaranth (Amaranthus cruentus) is a possible alternative to high-nutritional-value crops. Amaranth seeds are considered to be one of the few sources of phytosqualene (up to 8%). The use of squalene and its hydrogenated form squalane in skincare formulations has been steadily increasing, and the demand for these compounds is expected to rise continuously. The aim of this study was to investigate the amaranth oilseed as a potential ingredient for cosmetic applications. First, an experimental design and optimization were carried out in order to obtain amaranth oil rich in squalane instead of squalene through catalytic hydrogenation. Under the optimal conditions, the resulting oil was fully hydrogenated, with higher stability, and more suitable for cosmetic uses. Furthermore, the effect of the addition of amaranth oil and squalane on the rheological and sensory characteristics of moisturizing cream formulations was assessed. As expected, higher contents of oil and polyunsaturated fatty acids were obtained by supercritical CO2 extraction, and were used for the next step of the experiment. Optimization of the experimental conditions resulted in fully hydrogenated amaranth oil, with higher stability and rich in squalane. Better quality of moisturizing cream formulations was achieved when W/O formulations were enriched with 2% oil, or by adding 1% oil and 1% squalane. The formulation rich in squalane showed a better overall quality compared to other formulations.

Advances in Infectious Disease Vaccine Adjuvants

Vaccines are one of the most significant medical interventions in the fight against infectious diseases. Since their discovery by Edward Jenner in 1796, vaccines have reduced the worldwide transmission to eradication levels of infectious diseases, including smallpox, diphtheria, hepatitis, malaria, and influenza. However, the complexity of developing safe and effective vaccines remains a barrier for combating many more infectious diseases. Immune stimulants (or adjuvants) are an indispensable factor in vaccine development, especially for inactivated and subunit-based vaccines due to their decreased immunogenicity compared to whole pathogen vaccines. Adjuvants are widely diverse in structure; however, their overall function in vaccine constructs is the same: to enhance and/or prolong an immunological response. The potential for adverse effects as a result of adjuvant use, though, must be acknowledged and carefully managed. Understanding the specific mechanisms of adjuvant efficacy and safety is a key prerequisite for adjuvant use in vaccination. Therefore, rigorous pre-clinical and clinical research into adjuvant development is essential. Overall, the incorporation of adjuvants allows for greater opportunities in advancing vaccine development and the importance of immune stimulants drives the emergence of novel and more effective adjuvants. This article highlights recent advances in vaccine adjuvant development and provides detailed data from pre-clinical and clinical studies specific to infectious diseases. Future perspectives into vaccine adjuvant development are also highlighted.

Using Dual Toll-like Receptor Agonism to Drive Th1-Biased Response in a Squalene- and α-Tocopherol-Containing Emulsion for a More Effective SARS-CoV-2 Vaccine

A diversity of vaccines is necessary to reduce the mortality and morbidity of SARS-CoV-2. Vaccines must be efficacious, easy to manufacture, and stable within the existing cold chain to improve their availability around the world. Recombinant protein subunit vaccines adjuvanted with squalene-based emulsions such as AS03™ and MF59™ have a long and robust history of safe, efficacious use with straightforward production and distribution. Here, subunit vaccines were made with squalene-based emulsions containing novel, synthetic toll-like receptor (TLR) agonists, INI-2002 (TLR4 agonist) and INI-4001 (TLR7/8 agonist), using the recombinant receptor-binding domain (RBD) of SARS-CoV-2 S protein as an antigen. The addition of the TLR4 and TLR7/8 agonists, alone or in combination, maintained the formulation characteristics of squalene-based emulsions, including a sterile filterable droplet size (<220 nm), high homogeneity, and colloidal stability after months of storage at 4, 25, and 40 °C. Furthermore, the addition of the TLR agonists skewed the immune response from Th2 towards Th1 in immunized C57BL/6 mice, resulting in an increased production of IgG2c antibodies and a lower antigen-specific production of IL-5 with a higher production of IFNγ by lymphocytes. As such, incorporating TLR4 and TLR7/8 agonists into emulsions leveraged the desirable formulation and stability characteristics of emulsions and can induce Th1-type humoral and cell-mediated immune responses to combat the continued threat of SARS-CoV-2.

Tropical Air Chemistry in Lagos, Nigeria

The Nigerian city of Lagos experiences severe air pollution as a result of emissions and subsequent atmospheric photochemistry and aerosol chemistry. A year-long study, between August 2020 and July 2021, included measurements of gas-phase and aerosol processes, with surface meteorology at six urban sites. The sites were selected to represent near seacoast conditions, urban sites, and inland locations near agricultural and grassland ecosystems. The observations included continuous concentrations for CO, SO2, NOx, O3, PM2.5, and PM10. Samples were collected and analyzed for speciated volatile organic compounds (VOCs) and particulate chemical composition including inorganic and organic chemical species. The average diel variations in concentrations indicated well-known local photochemistry resulting from the presence of combustion sources, including motor vehicles, petroleum production and use, and open burning. The annual diel characteristics were emission-dependent and were modulated by meteorological variability, including the sea breeze and the seasonal changes associated with monsoons and Harmattan winds. Gases and particulate matter varied daily, consistent with the onset of source activities during the day. Fine particles less than 2.5 μm in diameter (PM2.5) included both primary particles from emission sources and secondary particles produced in the atmosphere by photochemical reactions. Importantly, particle sources included a large component of dust and carbonaceous material. For the latter, there was evidence that particle concentrations were dominated by primary sources, with little secondary material formed in the atmosphere. From complementary measurements, there were occasions when regional chemical processes affected the local conditions, including transportation, industry, commercial activity, and open waste burning.

Recent advances in the microbial production of squalene

Squalene is a triterpene hydrocarbon, a biochemical precursor for all steroids in plants and animals. It is a principal component of human surface lipids, in particular of sebum. Squalene has several applications in the food, pharmaceutical, and medical sectors. It is essentially used as a dietary supplement, vaccine adjuvant, moisturizer, cardio-protective agent, anti-tumor agent and natural antioxidant. With the increased demand for squalene along with regulations on shark-derived squalene, there is a need to find alternatives for squalene production which are low-cost as well as sustainable. Microbial platforms are being considered as a potential option to meet such challenges. Considerable progress has been made using both wild-type and engineered microbial strains for improved productivity and yields of squalene. Native strains for squalene production are usually limited by low growth rates and lesser titers. Metabolic engineering, which is a rational strain engineering tool, has enabled the development of microbial strains such as Saccharomyces cerevisiae and Yarrowia lipolytica, to overproduce the squalene in high titers. This review focuses on key strain engineering strategies involving both in-silico and in-vitro techniques. Emphasis is made on gene manipulations for improved precursor pool, enzyme modifications, cofactor regeneration, up-regulation of limiting reactions, and downregulation of competing reactions during squalene production. Process strategies and challenges related to both upstream and downstream during mass cultivation are detailed.

Bioactive Compound Profiling of Olive Fruit: The Contribution of Genotype

The health, therapeutic, and organoleptic characteristics of olive oil depend on functional bioactive compounds, such as phenols, tocopherols, squalene, and sterols. Genotype plays a key role in the diversity and concentration of secondary compounds peculiar to olive. In this study, the most important bioactive compounds of olive fruit were studied in numerous international olive cultivars during two consecutive seasons. A large variability was measured for each studied metabolite in all 61 olive cultivars. Total phenol content varied on a scale of 1–10 (3831–39,252 mg kg−1) in the studied cultivars. Squalene values fluctuated over an even wider range (1–15), with values of 274 to 4351 mg kg−1. Total sterols ranged from 119 to 969 mg kg−1, and total tocopherols varied from 135 to 579 mg kg−1 in fruit pulp. In the present study, the linkage among the most important quality traits highlighted the scarcity of cultivars with high content of at least three traits together. This work provided sound information on the fruit metabolite profile of a wide range of cultivars, which will facilitate the studies on the genomic regulation of plant metabolites and development of new olive genotypes through genomics-assisted breeding.

From Sharks to Yeasts: Squalene in the Development of Vaccine Adjuvants

Squalene is a natural linear triterpene that can be found in high amounts in certain fish liver oils, especially from deep-sea sharks, and to a lesser extent in a wide variety of vegeTable oils. It is currently used for numerous vaccine and drug delivery emulsions due to its stability-enhancing properties and biocompatibility. Squalene-based vaccine adjuvants, such as MF59 (Novartis), AS03 (GlaxoSmithKline Biologicals), or AF03 (Sanofi) are included in seasonal vaccines against influenza viruses and are presently being considered for inclusion in several vaccines against SARS-CoV-2 and future pandemic threats. However, harvesting sharks for this purpose raises serious ecological concerns that the exceptional demand of the pandemic has exacerbated. In this line, the use of plants to obtain phytosqualene has been seen as a more sustainable alternative, yet the lower yields and the need for huge investments in infrastructures and equipment makes this solution economically ineffective. More recently, the enormous advances in the field of synthetic biology provided innovative approaches to make squalene production more sustainable, flexible, and cheaper by using genetically modified microbes to produce pharmaceutical-grade squalene. Here, we review the biological mechanisms by which squalene-based vaccine adjuvants boost the immune response, and further compare the existing sources of squalene and their environmental impact. We propose that genetically engineered microbes are a sustainable alternative to produce squalene at industrial scale, which are likely to become the sole source of pharmaceutical-grade squalene in the foreseeable future.

Extraction of Squalene From Tea Leaves (Camellia sinensis) and Its Variations With Leaf Maturity and Tea Cultivar

Squalene is a precursor of steroids with diverse bioactivities. Tea was previously found to contain squalene, but its variation between tea cultivars remains unknown. In this study, tea leaf squalene sample preparation was optimized and the squalene variation among 30 tea cultivars was investigated. It shows that squalene in the unsaponified tea leaf extracts was well separated on gas chromatography profile. Saponification led to a partial loss of squalene in tea leaf extract and so it is not an essential step for preparing squalene samples from tea leaves. The tea leaf squalene content increased with the maturity of tea leaf and the old leaves grown in the previous year had the highest level of squalene among the tested samples. The squalene levels in the old leaves of the 30 tested cultivars differentiated greatly, ranging from 0.289 to 3.682 mg/g, in which cultivar “Pingyun” had the highest level of squalene. The old tea leaves and pruned littering, which are not used in tea production, are an alternative source for natural squalene extraction.

A gas chromatography-mass spectrometry method for quantifying squalane and squalene in aerosol emissions of electronic cigarette, or vaping, products

Numerous chemicals of unknown inhalational toxicity have been measured in electronic cigarette, or vaping, products (EVPs). In addition, little is known about the liquid-to-aerosol transmission and deliveries of these chemicals, including oil-like terpenes such as squalene (SQE) and squalane (SQA). To provide information on the aerosol deliveries of these compounds from EVPs, we developed and validated a quantitative method to measure squalene and squalane in EVP aerosol emissions. Validation parameters include measurement repeatability (SQA and SQE %RSD <6%), intermediate precision (SQA: %RSD 11%, SQE: %RSD 17%), accuracy (SQA: 86-107%, SQE: 104-113%), matrix effects, method robustness, and analyte stability. Limits of detection were 6.06 ng/mL puffed air volume for both squalene and squalane. The method was used to measure squalene and squalane in aerosol emissions of 153 EVPs associated with case patients from a recent outbreak of e-cigarette, or vaping, product use associated lung injury (EVALI). The EVPs analyzed were organized into nicotine, cannabidiol, and tetrahydrocannabinol products by the percentage of nicotine, cannabidiol, and tetrahydrocannabinol in total particulate matter after vaping. In case-associated tetrahydrocannabinol products the detection rates and mean concentrations were 82.4% and 33.0 ng/mL puffed air for squalene and 4.41% and 7.80 ng/mL puffed air for squalane.

DNA Microarray-Based Global Gene Expression Profiling in Human Amniotic Epithelial Cells Predicts the Potential of Microalgae-Derived Squalene for the Nervous System and Metabolic Health

In recent years, perinatal stem cells, such as human amniotic epithelial cells (hAECs), have attracted increasing interest as a novel tool of stem cell-based high-throughput drug screening. In the present study, we investigated the bioactivities of squalene (SQ) derived from ethanol extract (99.5%) of a microalgae Aurantiochytrium Sp. (EEA-SQ) in hAECs using whole-genome DNA microarray analysis. Tissue enrichment analysis showed that the brain was the most significantly enriched tissue by the differentially expressed genes (DEGs) between EEA-SQ-treated and control hAECs. Further gene set enrichment analysis and tissue-specific functional analysis revealed biological functions related to nervous system development, neurogenesis, and neurotransmitter modulation. Several adipose tissue-specific genes and functions were also enriched. Gene-disease association analysis showed nervous system-, metabolic-, and immune-related diseases were enriched. Altogether, our study suggests the potential health benefits of microalgae-derived SQ and we would further encourage investigation in EEA-SQ and its derivatives as potential therapeutics for nervous system- and metabolism-related diseases.

Haloarchaea have a high genomic diversity for the biosynthesis of carotenoids of biotechnological interest

Haloarchaea are mostly components of the microbial biomass of saline aquatic environments, where they can be a dietary source of heterotrophic metazoans or contribute to flamingo's plumage coloration. The diversity of secondary metabolites (SMs) produced by haloarchaea, which might play multiple ecological roles and have diverse biotechnological applications has been largely understudied. Herein, 67 haloarchaeal complete genomes were analyzed and 182 SMs biosynthetic gene clusters (BGCs) identified that encode the production of terpenes (including carotenoids), RiPPs and siderophores. Terpene BGCs were further analysed and it was concluded that all haloarchaea might produce squalene and bacterioruberin, which one a strong antioxidant. Most of them have other carotenoid BGCs that include a putative β-carotene ketolase that was not characterized so far in haloarchaea, but may be involved with canthaxanthin's biosynthesis. The production of bacterioruberin by Haloferax mediterranei ATCC 33500 was found to be not related to its antimicrobial activity.

Engineering of cis-Element in Saccharomyces cerevisiae for Efficient Accumulation of Value-Added Compound Squalene via Downregulation of the Downstream Metabolic Flux

Transcriptional downregulation is widely used for metabolic flux control. Here, marO, a cis-element of Escherichia coli mar operator, was explored to engineer promoters of Saccharomyces cerevisiae for downregulation. First, the ADH1 promoter (P_ADH1) and its enhanced variant P_UADH1 were engineered by insertion of marO into different sites, which resulted in decrease in both gfp5 transcription and GFP fluorescence intensity to various degrees. Then, marO was applied to engineer the native ERG1 and ERG11 promoters due to their importance for accumulation of value-added intermediates squalene and lanosterol. Elevated squalene content (4.9-fold) or lanosterol content (4.8-fold) and 91 or 28% decrease in ergosterol content resulted from the marO-engineered promoter P_ERG1(M5) or P_ERG11(M3), respectively, indicating the validity of the marO-engineered promoters in metabolic flux control. Furthermore, squalene production of 3.53 g/L from cane molasses, a cheap and bulk substrate, suggested the cost-effective and promising potential for squalene production.

On the Squalene Content of CV Chondrolia Chalkidikis and Chalkidiki (Greece) Virgin Olive Oil

This work is a continuation of efforts to establish the nutritional profile of virgin olive oil (VOO) from cv. Chondrolia Chalkidikis and Chalkidiki and to strengthen its positioning in the global VOO landscape. VOOs produced at an industrial scale in different olive mills of the Chalkidiki (Greece) regional unit as well as VOOs obtained at the laboratory scale from drupes of different maturity stages for four consecutive harvesting years were examined for their squalene (SQ) content using both HPLC and GC procedures. The mean values of SQ were found to be 4228 (HPLC) and 4865 (GC) mg/kg oil (n = 15) and were of the same magnitude as that in VOOs from cv Koroneiki (4134 mg/kg, n = 23). Storage of VOOs in the dark at room temperature for 18 months indicated an insignificant mean SQ content loss (~2%) in comparison to a mean loss of 26% for alpha-tocopherol content. This finding strengthens our view that SQ does not act as a radical scavenger that donates hydrogen atoms to the latter. The four consecutive harvest years studied indicated a clear declining trend in VOO SQ concentration upon olive ripening. To our knowledge, this is the first systematic work concerning the SQ content of Chondrolia Chalkidikis and Chalkidiki VOOs.

Evaluating the efficacy of extracted squalene from seed oil in the form of microemulsion for the treatment of COVID-19: A clinical study

This study investigates the effect of the nanostructure of squalene in the form of microemulsion on COVID‐19 patients. In this blinded clinical trial, a comparison was made between the efficacy of squalene treatment and controls. A total of 30 COVID‐19 patients admitted to the emergency department, and the infection ward was equally allocated to case (n = 15) and control (n = 15) groups according to their age and underlying diseases. The baseline characteristics of subjects, including age, gender, time of treatment onset, underlying condition, white blood cells count, and lymphocyte count were similar (p < 0.05). Baseline laboratory tests and computed tomography (CT) scans were performed for the study groups. The treatment group received 5 mg of intravenous squalene twice a day and standard treatment for 6 days, while controls received only standard treatment. After 6 days of treatment, clinical and CT scan changes were evaluated and compared in intervention and control groups. The need for oxygen therapy (p = 0.020), 2 days of no fever (p = 0.025), cough alleviation (p = 0.010), and lung high‐resolution computed tomography improvement (p = 0.033) were significantly different between cases and controls within 7 days of admission. No adverse effects were observed in the treatment group. Our data suggest that squalene could be considered as a potential treatment for COVID‐19, and further studies are required to confirm the results.

Determination of phytocomponents and validation of squalene in ethanolic extract of Clerodendrum serratum Linn roots—using gas chromatography-mass spectroscopy and GC-FID technique

Background

Clerodendrum serratum Linn commonly known as Bharangi in India has wide applications in the Ayurveda and Siddha system of medicine which has been attributed to the treatment of various diseases like asthma, cough, fever, rheumatism, and cephalalgia ophthalmia. Squalene has nutritional, medicinal, and pharmaceutical health benefits, hence possess antioxidant and cytoprotective effects.

Method

The study presents the GC-MS analysis of phytoconstituents present in the Clerodendrum serratum roots and further estimation of one of the constituents, i.e., squalene which is ought to be present in the roots as per mass spectral data obtained. Squalene was determined from the ethanolic extract of C. serratum roots using GC-FID without derivatization.

Results

Four major constituents, i.e., squalene, methyl palmitate, hexadecenoic acid, and stigmasterol were detected by GC-MS. Squalene from the extract was eluted at 17.5min which was confirmed with the standard squalene peak eluted at the same retention time. The linearity range chosen was 5–30ug/mL, and the method was found to be pretty linear (R=0.995), accurate with satisfactory repeatability. Hence, the phytochemical compounds were detected by GC-MS and the squalene was determined and validated according to the ICH guidelines.

Conclusion

Thus, the green gas chromatographic method can be used for quantification and qualification of active constituents in the roots of ethanolic extract of C. serratum. In addition, the presence of metabolite squalene by the GC-FID method was developed for the extract which is simple, fast, and environmentally friendly.

Bio-Based Crosslinked Polymers Synthesized from Functionalized Soybean Oil and Squalene by Thiol-Ene UV Curing

The development of polymers photopolymerized from renewable resources are extensively growing as fulfills green chemistry and green engineering principles. With the rapid growth of consumerism, research on innovative starting materials for the preparation of polymers may help to reduce the negative impact of petroleum-based plastic materials on the global ecosystem and on animal and human health. Therefore, bio-based crosslinked polymers have been synthesized from functionalized soybean oil and squalene by thiol-ene ultra-violet (UV) curing. First, thiol-ene UV curing of squalene was performed to introduce thiol functional groups. Then, hexathiolated squalene was used as a crosslinker in click UV curing of acrylated epoxidized soybean oil. Two photoinitiators, 2-hydroxy-2-methylpropiophenone and ethylphenyl (2,4,6-trimethylbenzoyl) phosphinate, were tested in different quantities. Rheological properties of the resins were monitored by real-time photorheometry. The characterization of obtained polymers was performed by differential scanning calorimetry, thermogravimetry, and Shore A hardness measurements. Polymers possessed higher storage modulus, thermal characteristics, Shore A hardness, and lower swelling value when ethylphenyl (2,4,6-trimethylbenzoyl) phosphinate was used as photoinitiator.

Impact of hydrothermal processing on squalene, α-tocopherol, and fatty acid content in Job's tears grain milled fractions: evaluation of their storage stability

BACKGROUND

Job's tears possess an exceptionally high amount of fat and the unsaponifiable fraction is a potential source of bioactive compounds. The aim of this study was to determine the effect of hydrothermal processing on squalene, α-tocopherol, and fatty acids in the whole-grain, milled fractions, and their storage stability.

RESULTS

The highest level of squalene content was found in the bran fractions of native and processed Job's tears (11.54-12.75 mg 100 g^-1 ). A remarkably high amount of α-tocopherol was also found in the bran (59.75 ± 0.47 mg 100 g^-1 ) and germ (67.05 ± 0.94 mg 100 g^-1 ) of the processed grain fractions. The storage stability evaluation of these bioactive compounds in the polished grains revealed no significant difference between 0 and 15 days of storage under elevated temprature of 37 °C and 92% relative humidity (accelarated storage conidition) and retained the bioactive compounds longer in the processed grains.

CONCLUSION

These results suggest that the processed Job's tears milled fractions with high bioactive compounds and improved shelf life can be used as food ingredients in product development. © 2020 Society of Chemical Industry.

A Novel Microfiber Wipe for Delivery of Active Substances to Human Skin: Clinical Proof of Concept

A novel technology for the delivery of active substances to the skin based on microfibers loaded with dried active substances was developed. The objective of this work was to demonstrate deposition of the active substances on the skin including concurrent cleansing properties of the wipe. As model active substance to measure deposition capacity Niacinamide was used and as parameter to measure cleansing capacities of the wipe squalene uptake was measured. Wipes loaded with niacinamide were used in the face and the forearm of 25 subjects. By means of Raman spectrometry the deposited niacinamide was analyzed before and after application. Wipes used on the face were analyzed for squalene to assess skin cleansing properties and for residual niacinamide. Forearm analysis including placebo and verum on left and right arm respectively was performed to rule out changes of the skin through application of the tissue. Measured amounts of niacinamide from face application demonstrate statistically significant results in the study population. Analysis of the wipes used show a liberation of 28.3% of niacinamide from the wipes and an uptake of 1.7 mg squalene per wipe. Results from forearm application show statistically significant differences (p < 0.05) between placebo and active for the complete study population. Sub group analyses are significant for both gender and ethnicity for face and forearm analysis respectively. Results clearly demonstrate deposition of niacinamide on the skin and the cleansing properties of the wipe. The institutional review board approved this prospective study.

Antioxidant effect of amaranth flour or protein isolate incorporated in high-fat diets fed to Wistar rats. Influence of dose and administration duration

This study evaluated the effect on Wistar rat's oxidative status of incorporating amaranth flour (AF) and protein isolate (AI) in increased-fat diets. Five of the groups were fed for 4 weeks with either BD (basal diet), Chol+F (2% cholesterol, 10% porcine fat), Chol+F+E (0.005% α-tocopherol), Chol+F+AF₁ or Chol+F+AI₁ (25% of protein replacement) diets. The other two groups were fed for 4 weeks with Chol+F and then 1 week with Chol+F+AF₂ or Chol+F+AI₂ diet (50% of protein replacement). Various effects on the oxidative stress biomarkers in tissues (intestine and liver) were observed. These effects were dependent on the ingredients, dose, and administration time. In the intestinal cells, Chol+F+AF₁ and Chol+F+AI₂ produced an increment in the reduced glutathione (GSH) content (56% and 39%, respectively), while Chol+F+AF₂ induced an increment in the superoxide dismutase (SOD) (25%) and glutathione peroxidase (GPx) (46%) activities. The presence of certain components in flour (e.g., fiber, polyphenols, squalene) could explain the higher activity recorded for AF. In the liver, Chol+F+AF₂ produced a decrease in SOD (19%) and GSH (36%), as well as an increase in GPx (255%); Chol+F+AI₁ and Chol+F+AI₂ also produced a decrease in GSH (36% and 24%, respectively) and important increments in GPx activity (273% for Chol+F+AI₁ and 2,900% for Chol+F+AI₂ ). These effects were dependent on the AI dose and were probably produced by absorbed peptides. PRACTICAL APPLICATIONS: It is known that redox imbalances are involved in the genesis of many chronic diseases. Therefore, it is possible to prevent them or limit their severity by improving the body's antioxidant defense mechanisms through dietary incorporation of antioxidant substances. The results suggest that amaranth protein isolate and amaranth flour have the potential for regulating intestinal and liver cells redox balance; effects were more evident when they contributed 50% of the diet's protein content and were administered for 1 week. Both amaranth ingredients could be used as ingredients in the development of functional foods with beneficial antioxidant properties.