Sterol Composition Research Articles

Investigating the Quality and Purity Profiles of Olive Oils from Diverse Regions in Selçuk, İzmir.

The Selçuk district of Izmir is one of the most essential regions in terms of olive oil production. In this study, 60 olive oil samples were obtained from five different locations (ES: Eski Şirince Yolu, KK: Kınalı Köprü, AU: Abu Hayat Üst, AA: Abu Hayat Alt, and DB: Değirmen Boğazı) in the Selçuk region of Izmir during two (2019-2020 and 2020-2021) consecutive cropping seasons. Quality indices (free acidity, peroxide value, p-Anisidine value, TOTOX, and spectral absorption at 232 and 270 nm) and the fatty acid, phenolic, and sterol profiles of the samples were determined to analyze the changes in the composition of Selcuk olive oils according to their growing areas. When the quality criteria were analyzed, it was observed that KK had the lowest FFA (0.11% oleic acid, PV (6.66 meq O2/kg), p-ANV (11.95 mmol/kg), TOTOX (25.28), and K232 (1.99) values and K270 had the highest value. During the assessment of phenolic profiles, the ES group exhibited the highest concentration of the phenolic compound p-HPEA-EDA (oleocanthal), with a content of 93.58 mg/kg, equivalent to tyrosol. Upon analyzing the fatty acid and sterol composition, it was noted that AU displayed the highest concentration of oleic acid (71.98%) and β-sitosterol (87.65%). PCA analysis illustrated the distinct separation of the samples, revealing significant variations in both sterol and fatty acid methyl ester distributions among oils from different regions. Consequently, it was determined that VOOs originating from the Selçuk region exhibit distinct characteristics based on their geographical locations. Hence, this study holds great promise for the region to realize geographically labeled VOOs.

Investigation of chemical properties and bioactive compounds of oils from different pumpkin seeds (Cucurbita pepo L.) during maturation

AbstractIn this study, seed and oil yields, protein, and moisture ratios of seeds of four different types of pumpkin seed varieties, namely Palancı population, VD1sn8, and VD1sn6 hybrid varieties and commercial variety grown in Edirne conditions in 2014 and 2015. Also, this study aimed to determine the change of fatty acid, tocopherol, and sterol composition of mentioned pumpkin seed varieties in three different periods from seed formation to final harvest time. During the ripening period, it was obtained that the oil yield increased, the moisture content of pumpkin seeds decreased. In the last harvest period, the oil yield of pumpkin seed varieties was determined to be between 37.21% and 42.07%. Protein ratios of all pumpkin seed species were found to be very close to each other (37.94%–39.28%) and statistically similar (p > 0.05). In 2014 and 2015, the dominant fatty acids for all pumpkin seed varieties are 18:1 (39.49%–46.95%) and 18:2 (32.57%–39.26%). Except for these fatty acids, 16:0 varies between 10.65% and 13.60% in all varieties; 18:0 varies at a ratio of 5.70%–6.38%. It is seen that the dominant tocopherol isomer is γ‐tocopherol for all pumpkin seed species in all harvest periods. In the last harvest period in 2014 and 2015, the amounts of γ‐tocopherol constitute 99.98%–84.95% and 86.91%–89.86% of the total tocopherol, respectively. It was observed that the tocopherol composition changed during the ripening period in all pumpkin seed species (p < 0.05). In general, the amount of sterols decreased during the ripening period for all cultivars in 2014 and 2015. In order from the highest to the least, β‐sitosterol, 5,24‐stigmastadienol, campesterol, Δ‐5 avenasterol, and stigmasterol were determined as phytosterols in pumpkin seed oils. Generally, β‐sitosterol ratios in all varieties were high in the 1st harvest period, decreased slightly in the 2nd harvest period, increased again until the 3rd harvest period and reached the values in the 1st harvest period in both 2014 and 2015.

Deletion of the Candida albicans TLO gene family results in alterations in membrane sterol composition and fluconazole tolerance.

Development of resistance and tolerance to antifungal drugs in Candida albicans can compromise treatment of infections caused by this pathogenic yeast species. The uniquely expanded C. albicans TLO gene family is comprised of 14 paralogous genes which encode Med2, a subunit of the multiprotein Mediator complex which is involved in the global control of transcription. This study investigates the acquisition of fluconazole tolerance in a mutant in which the entire TLO gene family has been deleted. This phenotype was reversed to varying degrees upon reintroduction of representative members of the alpha- and beta-TLO clades (i.e. TLO1 and TLO2), but not by TLO11, a gamma-clade representative. Comparative RNA sequencing analysis revealed changes in the expression of genes involved in a range of cellular functions, including ergosterol biosynthesis, mitochondrial function, and redox homeostasis. This was supported by the results of mass spectrometry analysis, which revealed alterations in sterol composition of the mutant cell membrane. Our data suggest that members of the C. albicans TLO gene family are involved in the control of ergosterol biosynthesis and mitochondrial function and may play a role in the responses of C. albicans to azole antifungal agents.

1,2,4-Triazole benzamide derivative TPB against Gaeumannomyces graminis var. tritici as a novel dual-target fungicide inhibiting ergosterol synthesis and adenine nucleotide transferase function.

Isopropyl 4-(2-chloro-6-(1H-1,2,4-triazol-1-yl)benzamido)benzoate (TPB) was a 1,2,4-triazole benzoyl arylamine derivative with excellent antifungal activity, especially against Gaeumannomyces graminis var. tritici (Ggt). Its mechanism of action was investigated by transmission electron microscopy (TEM) observation, assays of sterol composition, cell membrane permeability, intracellular ATP and mitochondrial membrane potential, and mPTP permeability, ROS measurement, RNA sequencing (RNA-seq) analysis. TPB interfered with ergosterol synthesis, reducing ergosterol content, increasing toxic intermediates, and finally causing biomembrane disruption such as increasing cell membrane permeability and content leakage, and destruction of organelle membranes such as coarse endoplasmic reticulum and vacuole. Moreover, TPB destroyed the function of adenine nucleotide transferase (ANT), leading to ATP transport obstruction in mitochondria, inhibiting mPTP opening, inducing intracellular ROS accumulation and mitochondrial membrane potential loss, finally resulting in mitochondrial damage including mitochondria swelled, mitochondrial membrane dissolved, and cristae destroyed and reduced. RNA-seq analyses showed that TPB increased the expression of ERG11, ERG24, ERG6, ERG5, ERG3 and ERG2 genes in ergosterol synthesis pathway, interfered with the expression of genes (NDUFS5, ATPeV0E, NCA2 and Pam17) related to mitochondrial structure, and inhibited the expression of genes (WrbA and GST) related to anti-oxidative stress. TPB exhibited excellent antifungal activity against Ggt by inhibiting ergosterol synthesis and destroying ANT function. So, TPB was a novel compound with dual-target mechanism of action and can be considered a promising novel fungicide for the control of wheat Take-all. The results provided new guides for the structural design of active compounds and powerful tools for pathogen resistance management. © 2023 Society of Chemical Industry.

Effects of Replacing Fishmeal with Algal Biomass (Pavlova sp. 459) on Membrane Lipid Composition of Atlantic Salmon (Salmo salar) Parr Muscle and Liver Tissues

A 12-week feeding trial examined the dietary impact of replacing fishmeal (FM) with algal biomass (AB) derived from Pavlova sp. strain CCMP459 (Pav459) in Atlantic salmon diets. Three distinct diets were formulated: a control diet featuring 20% FM and 7% fish oil (FO), an experimental diet incorporating a 50:50 blend of FM and AB Pav459 and reduced FO (10% FM; 4.5% FO; 10% AB), and a second experimental diet with full replacement of FM with AB Pav459 and further reduction in FO (1.75% FO; 20% AB). Replacing FM with AB Pav459 showed no significant effects on the growth performance of Atlantic salmon. Fish across all diets exhibited growth exceeding 200% from their initial weight. Analysis of total lipid content after the 12-week trial revealed no significant differences among the diets. However, individual proportions of omega-3 (ω3) and omega-6 (ω6) fatty acids varied. Fatty acid profiling in muscle and liver tissues showed distinct compositions reflective of dietary treatments. Linoleic acid (LA) and α-linolenic acid (ALA) exhibited higher proportions in total fatty acids than in membrane lipids. Docosahexaenoic acid (DHA) emerged as the predominant fatty acid in the membranes of both liver and muscle tissues. Furthermore, an analysis of sterol composition in Pavlova and salmon muscle tissue showed the presence of important sterols, including conventionally animal-associated cholesterol. This emphasizes the suitability of microorganisms, such as Pav459, for synthesizing diverse nutrients. Stable isotope analysis demonstrated direct incorporation of eicosapentaenoic acid (EPA) and DHA from diets into salmon tissues. Notably, minimal biosynthesis from the precursor ALA was observed, reaffirming the utility of Pav459-derived fatty acids. The EPA+DHA proportions in the fillet consistently met daily human consumption requirements across all dietary conditions, supporting the use of Pav459 algal biomass as an alternative to FM.

Deciphering the effect of salinity and boron stress on broccoli plants reveals that membranes phytosterols and PIP aquaporins facilitate stress adaptation

Abiotic stresses, such as salinity and boron toxicity/deficiency, are prevalent in arid and semi-arid regions where broccoli is largely cultivated. This study aimed to investigate the physiological response of broccoli leaves to these stresses, focusing on parameters such as growth, relative water content, stomatal conductance, and mineral concentration after 15 days of treatment application. The effects of individual and combined stresses of salinity and boron (deficiency and toxicity) were examined. Additionally, the study explored the molecular aspects of PIP aquaporins in relation to their presence in the plasma membrane and their interaction with the lipid environment. The results showed that the combined stress of salinity and boron deficiency resulted in a significant reduction in plant biomass, suggesting a specific adaptation to this stress combination. Changes in stomatal conductance and mineral nutrient levels indicated that the adaptation mechanisms were associated with water and boron concentration in the leaves. The expression patterns of PIP aquaporins varied among the different stress treatments, either individually or in combination. Furthermore, the presence of aquaporins in the plasma membrane and microsomal fraction highlighted the potential regulatory roles of trafficking along with the membrane composition, particularly the concentration of phytosterols. The results underscore the importance of water transport by aquaporins and their interaction with the sterol composition in the membranes, in facilitating salinity-boron stress adaptation mechanisms.

Study of the Chemical Composition of Carica papaya L. Seed Oils of Various Geographic Origins

The papaya plant (Carica papaya L.) is tree-like fruit plant cultivated throughout the tropics and subtropics. The aim of this study was to compare the physicochemical properties, fatty acid, sterols, and triterpenic alcohols composition of Carica papaya L. seed oils grown in a typical geographical location and Carica papaya L. seed oils grown in an untypical geographical location in greenhouse conditions (Saratov Region, Russia). The oils were extracted from the seeds of Carica papaya L. fruits collected in Kenya, the Dominican Republic, Angola, Ghana, and Brazil, as well as from the seeds of fruit plants grown in a similar environment (Russian Federation, Saratov). Parameters such as the oil yield, refractive index, peroxide value, iodine value, saponification value, and acid value of the extracted Carica papaya L. seed oils were determined. The qualitative and quantitative chemical compositions of the seed oils were determined by a combination of mass spectrometry and NMR spectroscopy. The profiles as well as the content of fatty acids, sterols, triterpenic alcohols, and benzyl isothiocyanate were established. The saponifiable fraction of the oils is mainly represented by triglycerides (98.7–99.4%), while di-(0.4–1.1%) and monoglycerides (0.1–0.3%) are also present but in smaller amounts. The content of sterols and triterpene alcohols was (537.5–918.2) mg/100 g of oil (0.54–0.92%), and up to 75% of the fraction was represented by β-sitosterol (55.9–66.7%) and its saturated analogue-sitostanol (11.0–15.7%). The physicochemical properties and the fatty acid, sterol, and triterpenic alcohol composition of seed oils from Carica papaya L. fruits, cultivated in Russia, is in the quantitative range of other samples, which suggests that Carica papaya L. can be grown in Russia for obtaining the seed oil.

Effect of cultivar and environment on chemical composition and geographical traceability of Spanish olive oils

AbstractThis study aimed to investigate the influence of cultivar and environment on the chemical composition of Arbequina and Empeltre olive oils, and their contribution to geographical identification of olive oils from Aragon. A total of 260 olive oil samples from different cultivars (Arbequina, Empeltre, Royal de Calatayud, Alquezrana, and Royeta de Asque) from the three main oil‐producing areas of Aragon, located in northeast Spain, were selected. Fatty acid and sterol composition were analyzed in the course of three crop years (2017, 2018, and 2019). Cultivar was found the main factor influencing the variability of palmitic, palmitoleic, and linolenic fatty acid content, whereas geographic origin was the main contributor to variation in oleic and linoleic fatty acids in Arbequina and Empeltre olive oils. Cultivar also had a significant impact on sterol composition, although the effect of the production area also showed a significant effect on these oils. Crop year showed limited relevance, except for oleic and linoleic fatty acids. The interaction between the environment (e.g., crop year and geographical factors) and the cultivar (Arbequina and Empeltre) exerted a significant influence on oleic/linoleic (O/L) ratio and Δ7‐stigmastenol content, particularly in the southeast area of Aragon during the crop year with higher temperatures and drier conditions. Principal component analysis (PCA) and discriminant analysis (DA) confirmed the discriminative potential of the geographic production zone as a factor enabling the differentiation of olive oils from Aragon based on the major fatty acids and sterols.

In-Vitro Antioxidant Potential of Beta-Sitosterol: A Preface.

Introduction Beta-sitosterol, a plant sterol, has been linked to antibacterial and antinociceptive effects. Plant sterols exhibit valuable medicinal properties, including anti-adhesive activities. The dietary composition of sterols includes carbohydrates, lipids, proteins, and various minerals, along with beneficial reinforcements like essential nutrients. Methodology This study primarily aims to evaluate the antioxidant potential of beta-sitosterol through assessments using diphenylpicrylhydrazyl (DPPH), hydrogen peroxide (H2O2), and total antioxidant assays. Results The investigation into beta-sitosterol's antioxidant properties revealed a positive correlation between its concentration and antioxidant activity. Similar trends were observed in the present study, indicating an increase in antioxidant activity at lower concentrations. Discussion and conclusion Our findings demonstrate that beta-sitosterol exhibits significant antioxidant activity in the tested samples. These results highlight beta-sitosterol's potential as a potent antioxidant and contribute to our understanding of its beneficial effects.

Developing Novel Coumarin-Containing Azoles Antifungal Agents by the Scaffold Merging Strategy for Treating Azole-Resistant Candidiasis.

The extensive use of antifungal drugs has resulted in severe drug resistance, making clinical treatment of fungal infections more difficult. Biofilm inhibitors can overcome drug resistance by inhibiting fungal biofilm formation. In this study, some coumarins with antibiofilm activity were merged into CYP51 inhibitors to produce novel molecules possessing potent antiresistance activity. As expected, most compounds exhibited excellent in vitro antifungal activity against pathogenic fungi, especially fluconazole-resistant candidiasis. Then, their mechanism was confirmed by sterol composition analysis and morphological observation. Biofilm inhibition and down-regulation of resistance-related genes were employed to confirm the compounds' antiresistance mechanisms. Significantly, compound A32 demonstrated fungicidal activity against fluconazole-resistant strain 904. Most importantly, compound A32 showed potent in vivo antifungal activity against pathogenic fungi and fluconazole-resistant strains. Preliminary pharmacokinetic and toxicity tests demonstrated that the compounds possessed favorable druggability. Taken together, compound A32 represents a promising lead to develop novel antifungal agents for treating azole-resistant candidiasis.

Exploration of Baicalein-Core Derivatives as Potent Antifungal Agents: SAR and Mechanism Insights.

Baicalein (BE), the major component of Scutellaria Baicalensis, exhibited potently antifungal activity against drug-resistant Candida albicans, and strong inhibition on biofilm formation. Therefore, a series of baicalein-core derivatives were designed and synthesized to find more potent compounds and investigate structure-activity relationship (SAR) and mode of action (MoA). Results demonstrate that A4 and B5 exert a more potent antifungal effect (MIC80 = 0.125 μg/mL) than BE (MIC80 = 4 μg/mL) when used in combination with fluconazole (FLC), while the MIC80 of FLC dropped from 128 μg/mL to 1 μg/mL. SAR analysis indicates that the presence of 5-OH is crucial for synergistic antifungal activities, while o-dihydroxyls and vic-trihydroxyls are an essential pharmacophore, whether they are located on the A ring or the B ring of flavonoids. The MoA demonstrated that these compounds exhibited potent antifungal effects by inhibiting hypha formation of C. albicans. However, sterol composition assay and enzymatic assay conducted in vitro indicated minimal impact of these compounds on sterol biosynthesis and Eno1. These findings were further confirmed by the results of the in-silico assay, which assessed the stability of the complexes. Moreover, the inhibition of hypha of this kind of compound could be attributed to their effect on the catalytic subunit of 1,3-β-d-glucan synthase, 1,3-β-d-glucan-UDP glucosyltransferase and glycosyl-phosphatidylinositol protein, rather than inhibiting ergosterol biosynthesis and Eno1 activity by Induced-Fit Docking and Molecular Dynamics Simulations. This study presents potential antifungal agents with synergistic effects that can effectively inhibit hypha formation. It also provides new insights into the MoA.

Sterol, tocopherol, and bioactive fatty acid differences between conventional, high-quality, and organic cow milk

Milk contains several components that are important for human nutrition and health. To date, studies on organic and conventional milk have focused on their gross composition and fatty acid content, but little attention has been paid to the differences between other minor components, such as sterols and vitamins that may have functional actions. The aim of this study was to investigate the nutritional differences among 3 types of milk from a dairy plant: conventional, high-quality, and organic (in compliance with European regulations) milk, focusing on minor components such as sterols of animal and plant origin (phytosterols), tocopherols, and bioactive fatty acids. Cholesterol ranged from 271.37 mg/100 g of fat in conventional milk to 278.76 mg/100 g of fat in organic milk. Lanosterol was the main minor animal sterol in cow milk (ranging from 3.41 to 4.37 mg/100 g of fat), followed by desmosterol. The amount of total plant sterols in the analyzed milk ranged from 4.43 mg/100 g of fat in organic to 4.71 mg/100 g of fat in high-quality milk. Brassicasterol was the main sterol of plant origin which varied from 2.6 mg/100 g of fat in conventional and organic milk, to 2.93 mg/100 g of fat in high-quality milk. The second most present phytosterol was β-sitosterol, which ranged from 0.86 mg/100 g of fat in conventional to 0.97 mg/100 g of fat in high-quality, and organic milk. The results of the study showed no significant differences in gross and sterol composition between the 3 types of milk. However, the only significant difference found was in the fatty acid profile, with a higher n-3 content found in high-quality milk than in conventional and organic milk. These findings suggest that the investigated product categories and labels have minimal effect on the sterol and fatty acid profile of commercial cow milk.

Impact of development periods on chemical properties and bioactive components of safflower (Carthamus tinctorius L.) varieties

AbstractThis study aimed to determine the chemical properties (fatty acid composition, oil content, sterol and tocopherol compositions) of the oils extracted from the seeds of safflower (Dinçer, Remzibey, Balci, Linas, Yenice, Olas) varieties harvested in different periods from flowering to ripening period. In parallel with the increase of harvest time, the humidity rate decreased, while the oil ratios increased. It was determined that palmitic (16:0) and stearic (18:0) acids, which are significant saturated fatty acids, and oleic (18:1) and linoleic (18:2) acids, which are unsaturated fatty acids, are quite high in the oils of all safflower varieties. These fatty acids showed significant changes from the first harvest to the last harvest. The total saturated fatty acid ratios decreased, while the amount of unsaturated fatty acids increased as the maturation progressed. The first and latest harvest samples of Dinçer, Remzibey, Balcı, Linas, Yenice, Olas cultivars were selected and their sterol and tocopherol compositions were examined. The highest level of sterol in all cultivars was β‐sitosterol and the amount of sterols decreased towards full maturity. It was determined that α‐tocopherol was the dominant tocopherol found in the safflower oils and the amount of tocopherol increased towards full maturity.

Sterol composition in plants is specific to pollen, leaf, pollination and pollinator

Sterols have several roles in planta, including as membrane components. Sterols are also essential nutrients for insects. Based on this, and the different functions of leaves and pollen, we tested the hypotheses that (a) the sterolome is different in leaves and pollen from the same plant, (b) pollens from wind- and insect pollinated plants comprise different sterols, and (c) sterol provision in pollen-rewarding angiosperms differs from nectar-rewarding species. A novel approach to sterolomics was developed, using LCMS to determine the sterol profile of leaf and pollen from a taxonomically diverse range of 36 plant species. Twenty-one sterols were identified unambiguously, with several more identified in trace amounts. C29 sterols dominated the sterolome in most plants. The sterol composition was significantly different in leaf and pollen and their main sterols evolved in different ways. The sterolome of pollen from animal- and wind-pollinated was also significantly different, but not between nectar- and pollen-rewarding species. Our results suggest that the sterol composition in different plant tissues is linked to their biological functions. Sterol composition in pollen might be driven by physical role rather than the nutrient needs of pollinating insects.

Whey and post-frying oil as substrates in the process of microbial lipids obtaining: a value-added product with nutritional benefits

AbstractYarrowia lipolytica has found many biotechnological applications. The species has a number of regulatory mechanisms to maintain cellular homeostasis, enabling biomass growth in complex media. The aim of this study was to evaluate the use of Y. lipolytica yeast as a platform for the simultaneous management of several industrial by-products and the production of microbial lipids with application potential in the chemical and food industries. Batch cultures of KKP 379 strain were conducted in media with post-frying rapeseed oil (PFO) and a by-product of curd cheese production—acid whey. To evaluate the potential of Yarrowia as a nutraceutical, quantitative and qualitative analyses of microbial sterols were carried out along with an assessment of the biomass mineral composition. It was indicated that the composition and content of sterols varied depending on the phase of cell growth in batch culture. During culture in medium with 20% (v/v) whey and 50 g/L PFO, the cellular lipid content reached 39% (w/w). The highest amount of sterols per dry biomass (7.38 mg/g) and cellular lipids (21.08 mg/g) was recorded after 38 h of culture. The dominant was ergosterol 12.10 mg/g (57%). In addition, the composition of carbon and nitrogen sources in the medium affected the content of selected elements in biomass, indicating that substrate modification can be a tool for manipulating the composition of yeast cells. The results of the study showed that the selection of waste substrates is an important factor in regulation of the cellular lipid accumulation efficiency, as well as the content of certain sterols.

NATÜREL ZEYTİNYAĞI TAĞŞİŞİNİN TESPİTİNDE STEROL KOMPOZİSYONU, ECN42 FARKI VE FTIR SPEKTROSKOPİSİNİN KULLANIMININ KARŞILAŞTIRMALI OLARAK İNCELENMESİ

Due to its high price and consumer demand, virgin olive oil is an essential product vulnerable to deception for unfair economic gain. In our research, sunflower, palm olein and cottonseed oil were used as adulterants in different amounts for the preparation of adulterated samples. Sterol composition, the difference in theoretical and actual equivalent carbon number 42 triglycerides (ΔECN42) value and FTIR spectra were used to classify the adulterated and virgin olive oil samples. Decision trees on Δ7-stigmastenol and campesterol allowed the detection of 10% and higher adulteration. ΔECN42 ad FTIR provided good detection of the adulterated samples, even for the mixed oils at 1% concentration. However, the detecting performance of the FTIR decreased as the virgin olive oil sample set expanded with different seasons and varieties. Correct multivariate approach and FTIR data selection significantly influence the performance of FTIR spectroscopy for detecting VOO adulteration.

Design, synthesis, and biological evaluation of novel boron-containing azoles as potential antifungal agents

A series of novel boron-containing azoles were designed, synthesized, and characterized via1H NMR, 13C-NMR, and HRMS. Subsequent antifungal tests in vitro revealed that the target compounds possessed moderate to exceptional efficacy against the five fluconazole-sensitive Candida strains. Most interesting is that these target compounds showed superior activity against fluconazole-resistant strains compared to positive drug fluconazole. To complete with the study of antifungal mechanism, the effect of target compounds on the sterol composition of fungal was investigated. Meantime, the target compound N01 might cause direct harm to the fungal cell wall and cell membrane. Furthermore, compound N01 was nearly non-toxic to mammalian MRC-5 cell with IC50 >100 μM. Molecular docking experiment revealed that compound N01 interacted with Candida albicans CYP51 in a similar to that of the eutectic small molecule VT-1161. These findings strongly suggested that compound N01 warrants further investigation as a potential azole CYP51 inhibitor.

Co-Microencapsulation of Sacha Inchi (Plukenetia huayllabambana) Oil with Natural Antioxidants Extracts.

Sacha inchi (Plukenetia huayllabambana) oil was co-microencapsulated with natural antioxidant extracts (NAE), such as camu-camu (Myrciaria dubia (HBK) Mc Vaugh) fruit, Añil variety Andean potato (Solanum tuberosum andigenum, and elderberry fruit (Sambucus peruviana). Gum Arabic and the ternary combination of gum Arabic (GA) + maltodextrin (MD) + whey protein isolate (WPI) at different formulations were used as coating materials for the encapsulation process using spray-drying. The moisture content, particle size distribution and morphology, total phenolic content, antioxidant activity, fatty acid and sterol composition, oxidative stability, and shelf-life were evaluated. Co-microcapsules of sacha inchi (P. huayllabambana) oil with camu camu skin extract (CCSE) at 200 ppm encapsulated with GA + MD + WPI had the highest total polyphenol content (4239.80 µg GAE/g powder), antioxidant activity (12,454.00 µg trolox/g powder), omega-3 content (56.03%), β-sitosterol (62.5%), greater oxidative stability (Oxidation Onset temperature of 189 °C), higher shelf-life (3116 h), and smaller particle sizes (6.42 μm). This research enhances the knowledge to obtain microcapsules containing sacha inchi (P. huayllabambana) oil with natural antioxidant extracts that could be used for the development of functional foods. Further research is needed to study the potential interactions and their influence between the bioactive components of the microcapsules and the challenges that may occur during scale-up to industrial production.

Increase in steryl glycoside levels and stimulation of lipid raft formation in azuki bean epicotyls under hypergravity conditions

Sterols are the main components of the plasma membrane and are involved in various plant membrane functions. Azuki bean (Vigna angularis (Wild.) Ohwi et Ohashi) seedlings were cultivated under hypergravity conditions, and changes in the levels and composition of membrane sterols in their epicotyls were analyzed. Under hypergravity conditions at 300 g, the levels of steryl glycosides and acyl steryl glycosides per unit length and per gram fresh weight greatly increased, which accounted for an increase in the total sterol levels. Stigmasterol, β-sitosterol, and campesterol were the most abundant sterols. Hypergravity decreased the proportion of stigmasterol but increased that of β-sitosterol. The fatty chains of acyl steryl glycosides mainly consisted of palmitic acid (C16:0), stearic acid (C18:0), linoleic acid (C18:2), and α-linolenic acid (C18:3), and their proportions were not modified under hypergravity conditions. In addition, the density of membrane microdomains, visualized with anti-Flotillin 1 antibody per unit area, increased by hypergravity, suggesting that lipid raft formation was stimulated. These results support the hypothesis that lipid rafts are involved in plant response and resistance to gravity.

Erg6 Acts as a Downstream Effector of the Transcription Factor Flo8 To Regulate Biofilm Formation in Candida albicans.

The yeast-to-hyphal morphotype transition and subsequent biofilm formation are important virulence factors of Candida albicans and are closely associated with ergosterol biosynthesis. Flo8 is an important transcription factor that determines filamentous growth and biofilm formation in C. albicans. However, the relationship between Flo8 and regulation of the ergosterol biosynthesis pathway remains elusive. Here, we analyzed the sterol composition of a flo8-deficient C. albicans strain by gas chromatography-mass spectrometry and observed the accumulation of the sterol intermediate zymosterol, the substrate of Erg6 (C-24 sterol methyltransferase). Accordingly, the transcription level of ERG6 was reduced in the flo8-deficient strain. Yeast one-hybrid experiments revealed that Flo8 physically interacted with the ERG6 promoter. Ectopic overexpression of ERG6 in the flo8-deficient strain partially restored biofilm formation and in vivo virulence in a Galleria mellonella infection model. These findings suggest that Erg6 is a downstream effector of the transcription factor Flo8 that mediates the cross talk between sterol synthesis and virulence factors in C. albicans. IMPORTANCE Biofilm formation by C. albicans hinders its eradication by immune cells and antifungal drugs. Flo8 is an important morphogenetic transcription factor that regulates the biofilm formation and in vivo virulence of C. albicans. However, little is known about how Flo8 regulates biofilm formation and fungal pathogenicity. Here, we determined that Flo8 directly binds to the promoter of ERG6 to positively regulate its transcriptional expression. Consistently, loss of flo8 results in the accumulation of the substrate of Erg6. Moreover, ectopic overexpression of ERG6 at least partially restores the biofilm formation and virulence of the flo8-deficient strain both in vitro and in vivo. This work provides a new perspective on the metabolic link between transcription factors and morphotypes in C. albicans.