Decrease In Lipid Content Research Articles

Analysis of potential volatile organic compounds in Sitophilus zeamais (Coleoptera: Curculionidae)-infestedwheat based on lipid oxidation-a reference to early and rapid detection method.

The maize weevil, Sitophilus zeamais Motschulsky, is a hidden pest that presents serious risk to grain quality during postharvest storage. Lipid-derived volatile detection is considered a key reference for early prediction of S. zeamais infestation. However, the exact compositions of fatty acids and volatile organic compounds (VOCs) in S. zeamais-infested wheat are yet to be determined. In this study, we aimed to explore the effect of S. zeamais infestation on lipid metabolism in wheat infested with S. zeamais eggs (4 days), larvae (20 days), pupae (35 days), and adults (45 days). Compared to those in the control group, the activities of lipid oxidation enzymes, such as lipase, lipoxygenase, and alcohol dehydrogenase, increased by 82.73%, 105.12%, and 487.86%, respectively, during the storage period of 1 life cycle of S. zeamais. Additionally, the fatty acid composition of S. zeamais-infested wheat was significantly altered (palmitic acid [1.10-fold], oleic acid [1.07-fold], and linoleic acid [0.95-fold]). Furthermore, 91 VOCs were identified in all wheat samples; then, multivariate statistical analyses categorized these samples into 4 groups: uninfested, longer storage, lightly infested, and heavily infested. Moreover, 31, 26, and 45 potential VOCs were identified to distinguish uninfested wheat from those in the other 3 groups. These results demonstrated that S. zeamais infestation induces an elevation in lipid-related enzymatic activities, which potentially leads to a decrease in lipid content alongside the production of specific VOCs (undecan-4-olide, heptaldehyde, and 2-nonenal). These findings provide novel insights for rapidly identifying grains infested by hidden pests and effectively managing these pests during grain storage.

Physicochemical properties and ellagic acid accumulation in Tenebriomolitor larvae fed with pomegranate peel-enriched media

Edible insects are a promising and sustainable food source for humans due to their low environmental footprint, high feed conversion ratio, and high protein content. Furthermore, the nutritional profile of the edible insects can be modified depending on the provided diet. The aim of this study was to evaluate the growth performance, proximate composition, and ellagic acid accumulation in Tenebriomolitor larvae fed on corn flour media enriched with pomegranate peel. Corn flour and pomegranate peel were mixed in a 1:1 ratio (w/w) (PCM) and 50 T.molitor larvae were added to each jar. After 12 days of rearing, the weight of T.molitor larvae fed on PCM and the control increased by 88.35% and 58.6%, respectively, compared to their initial values. An increase in carbohydrate, protein and ash contents, along with a decrease in lipid content, was observed in the control diet after 12 days of feeding compared to the initial larvae. Conversely, the PCM diet exhibited an increase in ash and carbohydrate contents and a decrease in lipid and protein contents after 12 days of feeding compared to the initial larvae. Total phenolic content (TPC) of T.molitor larvae did not significantly vary when fed with the control group, while it increased on the fourth and twelfth days for larvae fed with the PCM diet. The CUPRAC antioxidant activity of larvae also increased on the fourth day of feeding on the PCM diet. Ellagic acid was not detected in larvae fed with control and initially, it accumulated in T.molitor larvae fed with PCM after 8 and 12 days of rearing, with concentrations of 92.54 and 115.6 µg/g larvae, respectively. This study highlights the importance of diet in changing the phenolic profile of T.molitor larvae, which can be used as a functional food ingredient to obtain value-added products from agricultural wastes.

Bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate Enhances foxo1-Mediated Lipophagy to Remodel Lipid Metabolism in Zebrafish Liver.

An emerging environmental contaminant, bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (TBPH), can bioaccumulate in the liver and affect hepatic lipid metabolism. However, the in-depth mechanism has yet to be comprehensively explored. In this study, we utilized transgenic zebrafish Tg (Apo14: GFP) to image the interference of TBPH on zebrafish liver development and lipid metabolism at the early development stage. Using integrated lipidomic and transcriptomic analyses to profile the lipid remodeling effect, we uncovered the potential effects of TBPH on lipophagy-related signaling pathways in zebrafish larvae. Decreased lipid contents accompanied by enhanced lipophagy were confirmed by the measurements of Oil Red O staining and transmission electron microscopy in liver tissues. Particularly, the regulatory role of the foxo1 factor was validated via its transcriptional inhibitor. Double immunofluorescence staining integrated with biochemical analysis indicated that the enhanced lipophagy and mitochondrial fatty acid oxidation induced by TBPH were reversed by the foxo1 inhibitor. To summarize, our study reveals, for the first time, the essential role of foxo1-mediated lipophagy in TBPH-induced lipid metabolic disorders and hepatoxicity, providing new insights for metabolic disease studies and ecological health risk assessment of TBPH.

Assessing the acclimatisation to the wild of stocked European graylings Thymallus thymallus by monitoring lipid dynamics and food consumption

This study investigated how 2+-year-old stocked pond-reared European graylings (Thymallus thymallus) acclimatised to a wild environment during six months (May–October 2019) after released. We examined the quantity and composition of lipids in the liver, muscles and visceral adipose tissues (VAT), as well as size parameters, condition factors and stomach contents. Our results showed a low post-stocking recapture rate (5.17%) of stocked fish after 6 months suggesting a poor acclimation to the wild environment. During the six months of monitoring, stocked fishes exhibited a sharp decrease in lipid content in all examined tissues, and, in the final month, lipid content was well below those of wild conspecifics. Stocked graylings preferred risky foraging behaviour and consumed numerous small drift preys with occasional hyperphagic events, thus experiencing strong bioenergetic challenges. Our study reveals that fish cultivated for extended periods struggle to acclimatise to the wild environment and that this commonly used stocking practice seems unsuccessful when aimed at strengthening wild grayling populations.

Pfaffia glomerata by‐product: drying, characterisation and utilisation in cereal bars

SummaryThis study aimed to evaluate the convective drying of a by‐product obtained by hydrodistillation of Pfaffia glomerata roots (PGB) and investigate the utilisation of the resulting powder in the preparation of cereal bars. Drying at 80 °C for 120 min was the selected condition for PGB due to the higher levels of phenolic acids (gallic, coumaric and ferulic) catechin and higher antioxidant activity than drying at 60 °C for 180 min, and, better technological properties and higher β‐ecdysone content than drying at 100 °C for 100 min. There was an increase in fibre content (110%), antioxidant compounds (97%) and compressive strength (377%) and a decrease in lipid content (31%) when the PGB content of cereal bars was increased from 0% to 9%. Colour parameters, purchase intention and most sensory parameters were similar among cereal bar formulations, indicating that PGB is a promising ingredient for the nutritional enrichment of cereal bars.

The Plasma Membrane H+ ATPase CsPMA2 Regulates Lipid Droplet Formation, Appressorial Development and Virulence in Colletotrichum siamense.

Plasma membrane H+-ATPases (PMAs) play an important role in the pathogenicity of pathogenic fungi. Lipid droplets are important storage sites for neutral lipids in fungal conidia and hyphae and can be used by plant pathogenic fungi for infection. However, the relationship between plasma membrane H+-ATPase, lipid droplets and virulence remains unclear. Here, we characterized a plasma membrane H+-ATPase, CsPMA2, that plays a key role in lipid droplet formation, appresorial development and virulence in C. siamense. Deletion of CsPMA2 impaired C. siamense conidial size, conidial germination, appressorial development and virulence but did not affect hyphal growth. ΔCsPMA2 increased the sensitivity of C. siamense to phytic acid and oxalic acid. CsPMA2 was localized to lipids on the plasma membrane and intracellular membrane. Deletion of CsPMA2 significantly inhibited the accumulation of lipid droplets and significantly affected the contents of some species of lipids, including 12 species with decreased lipid contents and 3 species with increased lipid contents. Furthermore, low pH can inhibit CsPMA2 expression and lipid droplet accumulation. Overall, our data revealed that the plasma membrane H+-ATPase CsPMA2 is involved in the regulation of lipid droplet formation and affects appressorial development and virulence in C. siamense.

Combined effect of few pesticides on proximate composition of liver in a fresh water fish, channa punctatus (bloch).

The present work is an endeavour to study the effect of three pesticides (namely - Metacid-50(M), Kelthane (K) and Dithane, M-45 (D) and their different combination on changes in biochemical composition (Water, lipid and non lipid fraction) in a fresh water teleostean fish, Channa punctatus (Bloch). In the liver of control group of fishes, the water, lipid and non lipid fractions (protein, carbohydrate and ash contents) were - 71.5%, 2.3% and 26.2% respectively. The water content of liver increased with the increasing concentration and exposure duration of pesticides except K+D mixed condition, where as water content increased at low concentration (i.e. 2.31 and 4.32 ppm) but at high concentration (5.96 ppm) the water content decreased after 24 hrs and increased after 48 hrs exposure. Decreased lipid content was obtained in all the concentrations except K+D mixed condition. In K+D mixed condition the lipid content increased from low to high concentration. The non lipid content decreased in all the experimental/treated animals. Statistical relationship between pesticides Vs. liver water and liver lipid have also been established.. KEYWORDS :Pesticides, liver water and lipid, fish.

Transcriptome Analysis Revealed the Advantages of Room Temperature Preservation of Concentrated Oocystis borgei Cultures for Use in Aquaculture.

Oocystis borgei, a microalgae species employed for regulating the quality of aquaculture water, demonstrates the capacity to adsorb noxious substances, curtail the growth of detrimental bacteria, and outcompete blooming cyanobacteria. It can be concentrated by natural sedimentation and stored at room temperature, making it costless and simple to transport and use. To study the mechanism of adaptation to room temperature preservation, O. borgei was concentrated (1.19 × 107-1.21 × 107 cell/mL) and stored for 50 days at low (5 °C, LT), normal (25 °C, NT), and high (35 °C, HT) temperatures, respectively. Polysaccharide content, lipid content, cell survival, and resuscitation were evaluated. RNA-Seq was also used to examine how concentrated O. borgei responded to temperature. During storage, there was an increase in polysaccharide content and a decrease in lipid content, with both being significantly upregulated in the LT and HT groups. Survival and cell density were highest in the NT group. The RNA-Seq analysis revealed extensive differences in transcript levels. ATP synthesis was inhibited in the LT group due to the reduced expression of PsaD, PsaE, PsaF, PsaK, and PsaL. Under HT, the formation of reactive oxygen species (ROS) was facilitated by low levels of redox-related genes (nirA) and high levels of oxidative genes (gdhA, glna, and glts). The findings suggest that storing concentrated O. borgei at room temperature is optimal for microalgae preservation, enhancing theoretical research in this field. Our study provides further theoretical and practical support for the development of O. borgei as a live ecological preparation for aquaculture microalgae ecology management.

Copine7 deficiency leads to hepatic fat accumulation via mitochondrial dysfunction

ObjectiveMitochondrial dysfunction affects hepatic lipid homeostasis and promotes ROS generation. Copine7 (CPNE7) belongs to the ubiquitous copine family of calcium-dependent phospholipid binding proteins. CPNE7 has a high calcium ion binding affinity and the capacity to scavenge reactive oxygen species (ROS). A recent study reported that abnormalities in fatty acid and lipid metabolism were linked to the gene variant of CPNE7. Therefore, the purpose of this study is to examine the role of Cpne7 in hepatic lipid metabolism based on mitochondrial function. MethodsLipid metabolism, mitochondrial function, and ROS production were investigated in high-fat diet (HFD)-fed Cpne7−/− mice and H2O2-damaged HepG2 hepatocytes following CPNE7 silencing or overexpression. ResultsCpne7 deficiency promoted severe hepatic steatosis in the HFD-induced NAFLD model. More importantly, mitochondrial dysfunction was observed along with an imbalance of mitochondrial dynamics in the livers of HFD-fed Cpne7−/−mice, resulting in high ROS levels. Similarly, CPNE7-silenced HepG2 hepatocytes showed high ROS levels, mitochondrial dysfunction, and increased lipid contents. On the contrary, CPNE7-overexpressed HepG2 cells showed low ROS levels, enhanced mitochondrial function and decreased lipid contents under H2O2-induced oxidative stress. ConclusionsIn the liver, Cpne7 deficiency causes excessive ROS formation and mitochondrial dysfunction, which aggravates lipid metabolism abnormalities. These findings provide evidence that Cpne7 deficiency contributes to the pathogenesis of NAFLD, suggesting Cpne7 as a novel therapeutic target for NAFLD.

In vitro evaluation of antiatherogenic potential of Origanum × paniculatum, Lippia alba, Clinopodium nepeta, and Eucalyptus globulus essential oils

IntroductionEssential oils (EOs) are mixtures of secondary plant metabolism compounds with potential lipid-lowering activity and antioxidant properties. They may therefore be considered as add-on therapy for the prevention and treatment of cardiovascular diseases. MethodsEOs of Origanum × paniculatum (OpEO), Lippia alba (chemotype linalool) (LaLEO), Clinopodium nepeta (CnEO) and Eucalyptus globulus (EgEO), were evaluated on THP-1 foam cell macrophages as a cellular model of atherogenesis. Cell viability was determined by the MTT assay, lipid content by thin-layer chromatography, and Oil Red O staining. Antioxidant activity was evaluated by TBARS on low-density lipoprotein lipid peroxidation, and by ABTS•+, DPPH•, and FRAP assays. EOs were characterised by gas chromatography–mass spectrometry and a predictive multivariate data analysis was performed by partial least square regression (PLS) to identify the components related to antiatherogenic potential. ResultsOpEO reduced foam cell viability (IC50 = 45 µl/l) and cholesterol and triacylglycerol content and demonstrated antioxidant activity. In contrast, LaLEO increased lipid content and showed a prooxidant capacity with low reduction of cell viability (IC50 = 340 µl/l). CnEO showed prooxidant activity and reduction of cell viability (IC50 = 130 µl/l) without changes in lipid content. EgEO showed antioxidant activity, lipid increase, and low cytotoxicity (IC50 = 770 µl/l). PLS analysis suggests that cis-sabinene hydrate is responsible for cell viability inhibition, thymol and β-cis-terpineol decrease lipid content and possess antioxidant activity, and linalool increases lipid levels and has prooxidant capacity. ConclusionsOpEO is a promising natural product for therapy against atherosclerosis, with cis-sabinene hydrate, thymol, and β-cis-terpineol as potential active principles.

Melanoma cells induce dedifferentiation and metabolic changes in adipocytes present in the tumor niche

BackgroundOne of the factors that affect the progression of melanoma is the tumor microenvironment, which consists of cellular elements, extracellular matrix, acidification, and a hypoxic state. Adipocytes are one of the types of cell present in the niche and are localized in the deepest layer of the skin. However, the relationship between fat cells and melanoma remains unclear.MethodsWe assessed the influence of melanoma cells on adipocytes using an indirect coculture system. We estimated the level of cancer-associated adipocyte (CAA) markers through quantitative PCR analysis. The fibroblastic phenotype of CAAs was confirmed by cell staining and western blotting analysis. The lipid content was estimated by lipid detection in CAAs using LipidSpot and by quantitative analysis using Oil Red O. The expression of proteins involved in lipid synthesis, delipidation, and metabolic processes were assessed through quantitative PCR or western blotting analysis. Lactate secretion was established using a Lactate-Glo™ assay. Proteins secreted by CAAs were identified in cytokine and angiogenesis arrays. The proliferation of melanoma cells cocultured with CAAs was assessed using an XTT proliferation assay. Statistical analysis was performed using a one-way ANOVA followed by Tukey’s test in GraphPad Prism 7 software.ResultsObtained CAAs were identified by decreased levels of leptin, adiponectin, resistin, and FABP4. Adipocytes cocultured with melanoma presented fibroblastic features, such as a similar proteolytic pattern to that of 3T3L1 fibroblasts and increased levels of vimentin and TGFβRIII. Melanoma cells led to a reduction of lipid content in CAAs, possibly by downregulation of lipid synthesis pathways (lower FADS, SC4MOL, FASN) or enhancement of lipolysis (higher level of phosphorylation of ERK and STAT3). Adipocytes cocultured with melanoma cells secreted higher IL6 and SerpinE1 levels and produced less CCL2, CXCL1, and angiogenic molecules. CAAs also showed metabolic changes comprising the increased secretion of lactate and enhanced production of glucose, lactate, and ion transporters. In addition, changes in adipocytes observed following melanoma coculture resulted in a higher proliferation rate of cancer cells.ConclusionsMelanoma cells led to decreased lipid content in adipocytes, which might be related to enhanced delipidation or reduction of lipid synthesis. Fibroblast-like CAAs showed metabolic changes that may be the reason for accelerated proliferation of melanoma cells.

Perspectives on the Probiotic Potential of Indigenous Moulds and Yeasts in Dry-Fermented Sausages.

The role of indigenous fungi in the appropriate development of sensory properties and the safety of dry-fermented sausages has been widely established. Nonetheless, their applications as probiotic agents have not been elucidated in such products yet, despite their promising functional features. Thus, it should be interesting to evaluate the probiotic potential of native Debaryomyces hansenii isolates from dry-fermented sausages and their application in the meat industry, because it is the most frequently isolated yeast species from these foodstuffs and its probiotic effects for animals as well as its possible probiotic activity for human beings have been demonstrated. Within the functional ability of foodborne yeasts, anti-inflammatory, antioxidant, antimicrobial, antigenotoxic, and immunomodulatory properties have been reported. Similarly, the use of dry-fermented sausages as vehicles for probiotic moulds remains a challenge because the survival and development of moulds in the gastrointestinal tract are still unknown. Nevertheless, some moulds have been isolated from faeces possibly from their spores as a form of resistance. Additionally, their beneficial effects on animals and humans, such as the decrease in lipid content and the anti-inflammatory activity, have been reported, although they seem to be more related to their postbiotic capacity due to the generated bioactive compounds with profunctional attributes than to their role as probiotics. Therefore, further studies providing knowledge useful for generating dry-fermented sausages with improved functionality are fully necessary.

Effects of thermal stress caused by the 2015–2016 El Niño on the biochemical composition, exoskeleton structure, and symbiont density of the fire coral Millepora alcicornis

Reef-forming cnidarians are essential for maintaining ecological balance. Unfortunately, coral reefs are endangered due to coral bleaching, which interrupts mutualistic symbiosis between Symbiodiniaceae algae and their coral hosts. Bleaching events result in very high coral mortality and the rapid deterioration of reef structures. Studies aimed at explaining the causes, mechanisms, and consequences of coral bleaching have been mainly conducted with anthozoans, while the impacts of thermal stress responsible for coral bleaching have been scarcely studied in hydrozoans, such as Millepora species (phylum Cnidaria, class Hydrozoa), which are the second most important reef-forming cnidarians. In the present study, the effects of thermal stress caused by the 2015–2016 El Niño on symbiont abundance, exoskeleton structure, and the biochemical composition of Millepora alcicornis were analyzed. Unbleached M. alcicornis specimens exhibited a higher abundance of Breviolum and Durisdinium species, which suggests that unbleached hydrocoral colonies might counteract thermal stress by hosting thermotolerant symbionts of the Durisdinium genus. Bleached hydrocorals exhibited lower levels of calcification than unbleached hydrocorals as well as changes in the microstructure of trabeculae and zooid pores. In contrast, thermal stress did not affect total calcium carbonate and carbohydrate content. Bleached tissues showed significantly higher levels of protein and refractory material, whereas their lipid content decreased considerably. The present study provides evidence that bleached M. alcicornis colonies suffered a decline in calcification and changes in the structure of their exoskeletons after being exposed to the 2015–2016 El Niño. The significant decrease in lipid content suggests that M. alcicornis primarily uses energy stores to maintain vital cellular processes at the expense of calcification.

Effect of a low ethanol concentration during in vitro maturation of bovine oocytes and subsequent embryo development

The present study investigated the effects of low ethanol exposure on bovine oocytes. Cumulus-oocyte complexes (COCs) were aspirated for the antral follicles of slaughterhouse-derived ovaries. These COCs were incubated in maturation medium containing 0, 0.1, and 0.2% ethanol for 21 h and subjected to fertilization and in vitro development, and then the rates of nuclear maturation, mitochondrial DNA copy number (Mt-cn) and protein (TOMM40), ATP content and lipid content in oocyte, fertilization, and blastulation were examined. Furthermore, COCs were incubated with 0 or 0.1% ethanol and then mitochondrial membrane potential (MMP) and the glucose consumption of COCs was determined. In addition, gene expression in oocytes was examined by RNA sequencing. Ethanol (0.1 and 0.2%) increased Mt-cn and Mt-protein levels whereas 0.2% ethanol increased the blastulation rate and ATP content in oocytes and decreased lipid content in oocytes. Ethanol (0.1%) increased MMP in oocytes and decreased glucose consumption of COCs. Eight stage embryos derived from 0.1% ethanol treated oocytes had higher levels of trimethyl-H3K9 compared with that of nontreated counterpart. RNA sequencing revealed that differentially expressed genes were associated with glycolysis/gluconeogenesis, carbon metabolism, sphingolipid metabolism, amino acid metabolism, and fatty acid degradation pathways. In conclusion, even 0.1% concentrations of ethanol during in vitro maturation considerably affects oocyte metabolism and histone configuration of embryos.

Assessment of lipid and pigment content in suspicious melanocytic lesions to improve melanoma detection.

Melanoma is a highly aggressive form of skin cancer and the most frequent lethal malignancy diagnosed by dermatologists. Although there have been advances for predicting melanoma prognosis, there are few highly sensitive and specific diagnostic tools for clinically evaluating suspicious melanocytic lesions prior to biopsy. We have recently determined that alterations in cellular lipid and pigment content are associated with tumor progression and melanoma metastasis. Here, we seek to determine if lipid droplet and pigment content assessments near the skin's surface are able to distinguish benign from malignant melanocytic lesions. We obtained 14 benign melanocytic lesions, classified as Melanocytic Pathology Assessment Tool and Hierarchy for Diagnosis (MPATH-Dx) class 1, and 22 malignant melanomas, classified as MPATH-Dx class 4 or 5, from Boston Medical Center. The malignant melanomas had an average greatest thickness of 1.8 ± 2.1 mm with 7/22 biopsies showing the presence of ulceration. Tissues were stained with the Fontana Masson stain to detect pigment or immunohistochemically stained for adipophilin, the main protein component of lipid droplets, to detect lipid droplets. Pigment and lipid droplets were quantified using ImageJ and CellProfiler, respectively. We found no significant difference in total pigment area between benign melanocytic lesions and malignant melanoma, and a 66% decrease in lipid content and 68% reduction in lipid/pigment content between benign melanocytic lesions and malignant melanoma ( P < 0.05). Our results suggest that lipid content and lipid/pigment content ratios may distinguish benign and malignant melanocytic lesions, which may be useful as a diagnostic tool for histopathologically challenging pigmented lesions.

TRIM21 attenuates renal carcinoma lipogenesis and malignancy by regulating SREBF1 protein stability

BackgroundMetabolic reprogramming is a hallmark of various cancers. Targeting metabolic processes is a very attractive treatment for cancer. Renal cell carcinoma (RCC) is a type of metabolic disease, and the lipidomic profile of RCC is significantly altered compared with that of healthy tissue. However, the molecular mechanism underlying lipid metabolism regulation in RCC is not clear.MethodsThe XF long-chain fatty acid oxidative stress test kits were used to assess the dependence on long-chain fatty acids and mitochondrial function after knockdown TRIM21 in RCC cells. The effect of TRIM21 on the lipid content in RCC cells was determined by metabolomics analysis, Oil Red O staining, and cellular Nile red staining. qRT-PCR and western blot were used to explore the relationship between TRIM21 and lipogenesis, and then the key molecule sterol regulatory element binding transcription factor 1 (SREBF1) was identified to interact with TRIM21 by immunoprecipitation, which was also identified in an orthotopic model. Subsequently, the relevance and clinical significance of TRIM21 and SREBF1 were analyzed by The Cancer Genome Atlas (TCGA) database, and 239 tissues were collected from RCC patients.ResultsTRIM21 silencing attenuated the dependence of RCC cells on fatty acids, and enhanced lipid accumulation in RCC cells. TRIM21 overexpression significantly decreased lipid contents by decreasing the expression of lipogenic enzymes via ubiquitination-mediated degradation of SREBF1. SREBF1 is critical for TRIM21-mediated lipogenesis inhibition in vitro and in vivo. Moreover, TRIM21 expression is negatively correlated with SREBF1 expression, and TRIM21-SREBF1 is a reliable combinational biomarker for RCC prognosis.ConclusionThe findings from this study reveal a novel pathway through which TRIM21 inhibits the lipid metabolism process of RCC and shed light on the development of targeted metabolic treatment and prognosis diagnosis of RCC.

Leonurine improves bovine oocyte maturation and subsequent embryonic development by reducing oxidative stress and improving mitochondrial function

It is acknowledged that excessive reactive oxygen species (ROS) level attributes greatly to the compromised developmental potential of oocytes matured in vitro. Although agents were applied to alleviate ROS levels, results were varied because of the distinct antioxidative activity and cell toxicity. Leonurine (LEO), extracted from the natural Chinese herb motherwort, is considered to be a potent free radical scavenger. Yet, it is undetermined whether LEO is benefit for oocyte development during in vitro maturation (IVM). In the present study, the effect of LEO on the quality of bovine oocyte as well as the underlying mechanism was investigated. We found that maturation rate (P < 0.01), subsequent blastocyst formation rate (P < 0.05), and the total blastocyst cell number (P < 0.05) after parthenogenetic activation were significantly increased in the group treated with 20 μM LEO. Moreover, a dramatic decline in ROS (P < 0.01), decreased lipid content (P < 0.01), elevated MMP level (P < 0.05), increased ATP content (P < 0.05), and reduced mitochondrial temperature (P < 0.01) were observed in oocytes treated with LEO. Furthermore, the expression level of anti-apoptotic protein BCL2 was significantly higher in LEO treated oocytes (P < 0.01), and the ratio of BAX/BCL2 was obvious decreased (P < 0.01). Finally, we found that LC3B intensity was significantly reduced (P < 0.05) while the rate of EdU positive nuclei was markedly increased (P < 0.05) in embryos derived from LEO-treated oocytes. Our results demonstrate that LEO exhibits a potent protective role in the acquisition of oocyte development capacity against oxidative stress during IVM, and provides a new solution for optimizing the in vitro culture system of bovine embryos.

Effects of feast-famine nutrient regimes on wastewater algal biofuel communities.

Microalgae accumulate lipids in response to nutrient deprivation, and these lipids are a biodiesel fuel stock. Algal cultivation with secondary wastewater effluent is one proposed platform for biofuel production, which provides nutrients to algae while further polishing wastewater effluent. Algal bioreactors were tested using a feast-famine feeding regiment in simulated secondary wastewater effluent to evaluate the effects on lipid content and algal community structure. Algal polycultures were inoculated into reactors fed with synthetic secondary wastewater effluent at pH 7.5 and 9 and operated under a feast-famine nutrient (N, P, and BOD) supply regime in sequencing batch reactors. Fatty acid methyl ester contents of the reactors were assessed, which showed a decrease in lipid content after the feast-famine cycling (from 12.2% initially to 5.2% after four cycles at pH 9). This decrease in lipid content was not correlated with an increase in carbohydrate storage within biomass, nor an increase in bacterial biomass abundance relative to algal biomass in the reactors. The eukaryotic microbial communities from reactors operated at pH 9 diverged from reactors operated at pH 7.5 during cycling, with the pH 9 reactors becoming dominated by a single Operational Taxonomic Unit aligning to the Scenedesmus genus. These results suggest that high pH and feast-famine nutrient cycling may select for a less diverse algal community with a lower lipid content within a secondary wastewater polishing scheme.

Effects of different oxygen regimes on ecological performance and bioenergetics of a coastal marine bioturbator, the soft shell clam Mya arenaria

Benthic species are exposed to oxygen fluctuations that can affect their performance and survival. Physiological effects and ecological consequences of fluctuating oxygen are not well understood in marine bioturbators such as the soft-shell clam Mya arenaria. We explored the effects of different oxygen regimes (21 days of exposure to constant hypoxia (~4.1 kPa PO2), cyclic hypoxia (~2.1–~10.4 kPa PO2) or normoxia (~21 kPa PO2)) on energy metabolism, oxidative stress and ecological behaviors (bioirrigation and bioturbation) of M. arenaria. Constant hypoxia and post-hypoxic recovery in cyclic hypoxia led to oxidative injury of proteins and lipids, respectively. Clams acclimated to constant hypoxia maintained aerobic capacity similar to the normoxic clams. In contrast, clams acclimated to cyclic hypoxia suppressed aerobic metabolism and activated anaerobiosis during hypoxia, and strongly upregulated aerobic metabolism during recovery. Constant hypoxia led to decreased lipid content, whereas in cyclic hypoxia proteins and glycogen accumulated during recovery and were broken down during the hypoxic phase. Digging of clams was impaired by constant and cyclic hypoxia, and bioirrigation was also suppressed under constant hypoxia. Overall, cyclic hypoxia appears less stressful for M. arenaria due to the metabolic flexibility that ensures recovery during reoxygenation and mitigates the negative effects of hypoxia, whereas constant hypoxia leads to depletion of energy reserves and impairs ecological functions of M. arenaria potentially leading to negative ecological consequences in benthic ecosystems.

Unanswered issues on decarbonizing the aviation industry through the development of sustainable aviation fuel from microalgae

Concerns have been raised about the effects of fossil fuel combustion on global warming and climate change. Fuel consumer behavior is also heavily influenced by factors such as fluctuating fuel prices and the need for a consistent and reliable fuel supply. Microalgae fuel is gaining popularity in the aviation industry as a potential source of energy diversification. Microalgae can grow in saltwater or wastewater, capture CO2 from the atmosphere and produce lipids without requiring a large amount of land. As a result, the production of oil from microalgae poses no threat to food availability. The low carbon footprint of microalgae-derived fuels has the potential to mitigate the impact of traditional aviation fuels derived from petroleum on climate change and global warming. Therefore, aviation fuels derived from microalgae have the potential to be a more environmentally friendly and sustainable alternative to conventional fuels. Gathering microalgal species with a high lipid content, drying them, and turning them into aviation fuel is an expensive process. The use of biofuels derived from microalgae in the aviation industry is still in its infancy, but there is room for growth. This study analyses the potential routes already researched, their drawbacks in implementation, and the many different conceptual approaches that can be used to produce sustainable aviation fuel from microalgal lipids. Microalgae species with fast-growing rates require less space and generate lipids that can be converted into biofuel without imperiling food security. The key challenges in algal-based aviation biofuel include decreased lipid content, harvesting expenses, and drying procedure that should be enhanced and optimized to increase process viability.