Carotenoid Content Research Articles

Association between two common SNPs, rs6564851 and rs6420424, and lutein and zeaxanthin levels in a cohort of US postmenopausal women with a family history of breast cancer.

A better understanding of the factors contributing to systemic concentrations of carotenoids is necessary given the weak correlations between circulating levels and dietary intake of carotenoids. Although genetic variation may play a key role in the interindividual variability in carotenoid concentrations, few genome-wide association studies (GWAS) have focused on carotenoids. We used a random sample (n = 519) of postmenopausal participants in the Sister Study with data on genotypes and plasma carotenoid levels to conduct GWAS for each of five carotenoids (mcg/mL): alpha-carotene, beta- carotene, cryptoxanthin, lycopene, and lutein/zeaxanthin. We used linear regression models and an additive genetic model to evaluate associations between 371,532 variants and inverse normal transformed carotenoid concentrations. We found evidence for one genome-wide statistically significant association with the combined carotenoids of lutein and zeaxanthin for rs6564851-C (beta = -0.377, se = 0.059, p = 4.6×10-10) and rs6420424-A (beta = -0.334, se = 0.059, p = 2.2×10-8), upstream of beta-carotene oxygenase 1 (BCO1) gene on chromosome 16. No other variant was associated with any of the remaining four carotenoids. Our results for the common rs6564851 and rs6420424 variants correspond to previous findings. Although biologic mechanisms explain the association between beta-carotene and the variants, the inverse association with lutein/zeaxanthin will require further investigation.

Role of Chitosan in the Coloring of Berries and Phytochemical Changes in Physalis angulata L. During Harvest Maturity

Physalis angulata L. berries are green in the initial stage of maturity and turn yellow when fully mature due to an increase in carotenoids. However, the coloration of the epidermis of the berry should not be the reference for harvesting maturity, since the calyx is fully closed. The use of an edible chitosan coating delays the color changes in the berry by reducing the respiration rate. This work studies the effect of harvest maturity and chitosan on the shelf life and berry coloring in Physalis angulata L. Three factors were considered, being harvest maturity stage (green mature (GM), yellowish-green (YG) and yellow (Y)), chitosan coating (0, 0.5, and 1%), and storage time (10, 20, 30 days). The fruits were stored at 20 °C and 85% Rh. The results showed that on the harvesting stage, chitosan coating had a significant effect on the quality and shelf life of berries during storage time. The value of carotenoid and phenol contents, flavor index, chroma, and hue significantly increased with berry maturity. Chitosan delayed the decrease in chlorophyll, phenol contents, antioxidant capacity, berry maturity, and color change. The results show that in the berries coated with 1% chitosan during storage, changes in color were less in comparison with the control condition (no chitosan). The highest decrease of hue angle and color index (17.92°) was observed in the control. The highest total antioxidant (78.42%) was observed after 30 days of storage in MG berries treated with a 0.5% chitosan coating.

Comparative Analysis of Pretreatment Methods for Fruit Waste Valorization in Euglena gracilis Cultivation: Impacts on Biomass, β-1,3-Glucan Production, and Photosynthetic Efficiency.

This study explored the sustainable valorization of fruit waste extracts from sugarcane bagasse (SB), banana peel (BP), and watermelon rind (WR) for Euglena gracilis biomass and β-1,3-glucan production. The extracts were prepared using water extraction (WE), high-temperature and pressure treatment (HTP), and dilute sulfuric acid treatment (DSA). The DSA-treated extracts consistently yielded the best results. E. gracilis cultured in SB-DSA showed the highest cell density with a 2.08-fold increase compared to the commercial HUT medium, followed by BP-DSA (1.35-fold) and WR-DSA (1.70-fold). Photosynthetic pigment production increased significantly, with chlorophyll a yield being highest in SB-DSA (1.90-fold increase). The chlorophyll a/b ratio and total carotenoid content also improved, indicating enhanced light-harvesting capacity and photoprotection. Photosynthetic efficiency, measured by chlorophyll fluorescence, notably improved. The maximum quantum yield of PSII (Fv/Fm) increased by up to 25.88% in SB-DSA, suggesting reduced stress and improved overall photosynthetic health. The potential photochemical efficiency (Fv/F0) showed even greater improvements: up to 40.53% in SB-DSA. Cell morphology analysis revealed larger cell aspect ratios, implying a more active cellular physiological state. β-1,3-glucan yield also increased by 23.99%, 12.92%, and 23.38% in SB-DSA, BP-DSA, and WR-DSA, respectively. This study demonstrates the potential of pretreated fruit waste as a cost-effective and sustainable medium for E. gracilis cultivation, offering the dual benefits of waste valorization and high-value compound production. These findings contribute to the development of more efficient biorefinery processes and align with the circular economy principles in food biotechnology.

Effects of Temperature and Salinity on the Growth, Reproduction, and Carotenoid Accumulation in Artemia sinica and Transcriptome Analysis

Brine shrimp (Artemia), rich in carotenoids, are widely used in intensive aquaculture to supplement nutrients and enhance the coloration of farmed organisms. This study investigates the growth, reproduction, and carotenoid accumulation in Artemia sinica under varying salinity and temperature conditions. The results showed that temperature and salinity displayed significant interactions with survival, body length, and carotenoid accumulation in the body. The optimal survival and growth conditions of A. sinica (Bohai Sea Gulf) were a temperature range of 25–30 °C and a salinity range of 30–50‰. High temperatures accelerated growth and sexual maturity at the expense of survival rates, while temperatures below 20 °C prevented ovigerous development. Extreme salinity levels negatively affected survival and growth, though high salinity promoted sexual maturity. Carotenoids in A. sinica mainly accumulate as echinenone and canthaxanthin form. Carotenoid accumulation decreased with increased temperature and salinity, and the temperature effect decreased with rising salinity. A. sinica cultivated at a salinity of 10‰ and a temperature of 25 °C exhibits the highest carotenoid content. Transcriptomic analysis revealed that high temperatures primarily affected genes related to stress response and metabolism, while high-salinity regulated genes associated with ion balance and signaling pathways. These findings provide a theoretical basis for enhancing Artemia sinica aquaculture and optimizing cultivation conditions, offering novel insights into nutritional and environmental impacts on brine shrimp biology.

Maize Morphophysiological Changes Modulated by Cover Crops Rotation in Northeast Brazil

Cover crops have gained attention due to their potential benefits for the soil and physiological performance of subsequent crops. This study aimed to evaluate the physiological and productive aspects of maize grown in succession to cover crops in northeastern Brazil. A randomized complete block design with four repetitions was employed, in which the treatments consisted of the following cover crops: sunn hemp, spectabilis, pigeon pea, Brachiaria sp., jack bean, millet, and fallow. Physiological aspects and production components of maize were evaluated at the tasseling (VT) and smooth grain (R3) phenological stages. Millet cover increased carotenoid content in maize leaves by up to 78% at R3. Maize grown after pigeon pea, millet, and Brachiaria sp. showed up to 42% greater CO2 assimilation efficiency compared to jack bean. Carboxylation efficiency increased by up to 34% in maize grown after millet and Brachiaria sp., while water use efficiency improved by up to 76% in maize after sunn hemp and pigeon pea at R3. Sunn hemp, spectabilis, and jack bean reduced soil temperature by 2 °C compared to fallow. The highest maize yield was observed after jack bean, with an 8% increase over fallow. These findings demonstrate the benefits of incorporating cover crops into maize cultivation systems in the semi-arid region of Brazil.

Functional, Antioxidant, Antibacterial, and Antifungal Activity of Edible Flowers

Edible flowers have been used since ancient times, but their potential for improving human health has not been explored. This study aimed to evaluate the profile of bioactive compounds (organic acids, phenolics, and carotenoids) and the antioxidant and antimicrobial activity of nine flower varieties with high concentrations of carotenoids or total phenolic compounds. Ninety-three edible flowers were analysed for physicochemical characteristics, total phenolic and carotenoid concentrations, and antioxidant activity (ABTS). Bioactive profiles were determined by rapid resolution liquid chromatography (RRLC), and antimicrobial activity was determined against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Streptococcus mutans, and Candida albicans and Candida tropicalis. Chrysanthemum x hybrid orange, Helianthus annuus yellow, Tagetes patula orange, Canna indica red, and Hibiscus rosa-sinensis (orange1 and yellow) showed significant concentrations of total carotenoids. In contrast, Pelargonium hortorum orange2, Hibiscus rosa-sinensis red1, and Rosa x hybrid variety medium yellow showed high levels of total phenolics. The predominant compounds in these species were citric acid (991.4 mg/g DW in Hibiscus rosa-sinensis red1), 4-hydroxybenzoic acid (936.2 mg/100 g DW in P. hortorum orange2), kaempferol (971. 9 mg/100 g DW in T. patula orange), quercetin glucoside (958.8 in C. x hybrid), quercetin (919.3 mg/100 g DW in T. patula), α-carotene, and β-carotene in T. patula orange (989.5 and 601.2 mg/100 g DW, respectively). Regarding antimicrobial activity, T. patula orange and P. hortorum orange2 inhibited bacterial growth, while C. x hybrid orange and P. hortorum orange2 inhibited Candida albicans, and the latter inhibited Candida tropicalis. These results indicate the potential of edible flowers as a natural source of bioactive compounds and as a tool in the fight against antimicrobial resistance.

Dietary stinging nettle (Urtica dioica) improves carotenoids content in laying hen egg yolk

ABSTRACT 1. This study assessed the addition of dried stinging nettle (SN) leaves at 0%, 2.5% and 5.0% in feed on egg production, egg quality, chemical composition and antioxidant content in eggs from laying hens. 2. Seventy-two Hy-Line Brown laying hens, housed in 36 enriched layer cages, were used in the study from 43 to 47 weeks of age. Feeding dry SN leaves did not affect (p > 0.05) egg production variables. 3. Dietary SN inclusion linearly increased (p < 0.001) carotenoid content more than six-fold, in addition to yellowness and redness of the yolks at the maximum inclusion. Providing eggs from hens fed carotenoid enriched diets, e.g. SN, may be used to increase carotenoids in human diets.

Screening the carotenoid in vitro bioaccessibility of purple corn breakfast cereal consumed with milk and plant-based milk

Chronic non-communicable diseases (NCD), such as cardiovascular diseases, diabetes, and cancer, dominate global mortality, besides compromising the quality of life. Unhealthy habits like sedentary lifestyles and poor diets escalate NCD risks. Conversely, the consumption of phenolic compounds and carotenoids has shown promise in reducing NCD risks. The food industry responds by adapting products to meet demands for healthier options rich in bioactive compounds. For instance, breakfast cereals made from purple and yellow corn offer carotenoids and anthocyanins and form a nutrient-balanced meal when consumed with milk or alternatives. However, bioactive compounds in food do not guarantee absorption, necessitating bioaccessibility studies. In this study, we aimed to evaluate the bioaccessibility of the major carotenoids in two breakfast cereals, one made with 100% yellow corn and the other with 50% purple corn, co-digested with whole milk, semi-skimmed milk, skimmed milk, and almond “milk”. The bioaccessibility of lutein in the breakfast cereals was evaluated using the INFOGEST 2.0 in vitro digestion method. Results showed that lutein bioaccessibility ranged from 9% to 29%. The bioaccessibility was lower than that observed in other food matrices, such as spinach and maize products. High fiber, low carotenoid contents, and anthocyanin presence negatively influenced the carotenoid bioaccessibility. Interestingly, the varying lipid content of milk showed no impact on lutein bioaccessibility under the examined conditions. In conclusion, the effects of lipids in a low range (0–7%) are not significant (p > 0.05) compared to other matrix components. When developing new products with health and nutritional benefits, it is important to consider that while fiber can reduce the bioaccessibility of carotenoids, it remains crucial for gut health.

Grain yellowness is an effective predictor of carotenoid content in global sorghum populations

Identification of high carotenoid germplasm is crucial to assist breeders in provitamin-A biofortification of sorghum (Sorghum bicolor [L.] Moench). High-performance liquid chromatography is the gold standard for carotenoid quantification, however, it is not feasible for large scale phenotyping due to its high cost and low throughput. In this study, we tested the feasibility of using grain color as a high-throughput method of carotenoid biofortification breeding. We hypothesized that visual, color-based selection can be an effective strategy to identify high-carotenoid accessions. Yellow grain had significantly higher carotenoid content than red, brown, and white grain. The degree of yellowness could distinguish the presence or absence of carotenoids, but could not distinguish carotenoid concentrations within yellow-only accessions. The degree of luminosity of the grain, however, was able to better predict carotenoid concentrations within yellow-only accessions. Genome-wide association studies identified significant marker-trait associations for qualitative and quantitative grain color traits and carotenoid concentrations near carotenoid pathway genes—ZEP, PDS, CYP97A, NCED, CCD, and LycE—three of which were common between grain color and carotenoid traits. These findings suggest that using grain color as a method for screening germplasm may be an effective high-throughput selection tool for prebreeding and early-stage breeding in carotenoid biofortification.

Integrated proteome and pangenome analysis revealed the variation of microalga Isochrysis galbana and associated bacterial community to 2,6-Di-tert-butyl-p-cresol (BHT) stress.

The phenolic antioxidant 2,6-Di-tert-butyl-p-cresol (BHT) has been detected in various environments and is considered a potential threat to aquatic organisms. Algal-bacterial interactions are crucial for maintaining ecosystem balance and elemental cycling, but their response to BHT remains to be investigated. This study analyzed the physiological and biochemical responses of the microalga Isochrysis galbana and the changes of associated bacterial communities under different concentrations of BHT stress. Results showed that the biomass of I. galbana exhibited a decreasing trend with increasing BHT concentrations up to 40mg/L. The reduction in chlorophyll, carotenoid, and soluble protein content of microalgal cells was also observed under BHT stress. The production of malondialdehyde and the activities of superoxide dismutase, peroxidase, and catalase were further determined. Scanning electron microscopy analysis revealed that BHT caused surface rupture of the algal cells and loss of intracellular nutrients. Proteomic analysis demonstrated the upregulation of photosynthesis and citric acid cycle pathways as a response to BHT stress. Additionally, BHT significantly increased the relative abundance of specific bacteria in the phycosphere, including Marivita, Halomonas, Marinobacter, and Alteromonas. Further experiments confirmed that these bacteria had the ability to utilize BHT as the sole carbon resource for growth, and genes related to the degradation of phenolic compounds were detected through pangenome analysis.

Cultivation Technology and Plant Density Affecting the Yield and Carotenoid Content of Beauregard Sweet Potato

Cultivation Technology and Plant Density Affecting the Yield and Carotenoid Content of Beauregard Sweet Potato

Comparison of the anti-inflammatory effects of carotenoids-rich product from microalgal mass-cultured between natural seawater and magma seawater

Microalgae can be mass-produced in a short period of time and are rich in high value-added product such as carotenoids, thereby it is widely used in a variety industrial field. However, the production cost expensed a lot due to high price of culture ingredient, vitamins. Additionally, >80% of synthetic carotenoids are used in industrial field, and their cost is also highly expensed. Therefore, in this study, a microalga, Tetraselmis sp. was mass-cultured using natural seawater (NS) and magma seawater (MS) as vitamins. As a result of comparing the general composition between the extracts cultured in two culture media, crude carbohydrate and crude lipid contents were 2.68% and 4.38% higher, respectively, while crude protein content was 4.1% lower in the MS culture media. The extraction yield was 8.6% higher in the MS than the NS culture media. Also, lutein and zeaxanthin were predominantly presented in the species and detected in the microalgal extract cultured in MS was 2- and 8-folds higher, respectively, than in NS. Consequently, the carotenoids-rich extracts cultured with two seawaters were exhibited prominent anti-inflammatory effects by suppressing nitric oxide (NO) overproduction and pro-inflammatory mediator such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase (COX)-2 expression through MAPKSs and NF-κB pathway. Interestingly, extract of microalgal cultured in MS showed a more efficient anti-inflammatory effect. These results suggest that the value of MS in increasing the carotenoids contents with beneficial effects in mass cultivation of microalgae.

Postharvest application of sodium nitroprusside improves the quality of ‘Umran’ ber fruit under cold storage conditions by regulating enzyme activities

ABSTRACT Ber fruit is highly perishable, with a storage life of only 3–5 days under ambient conditions, which makes it difficult to transport the fruit even to domestic markets. An experiment was conducted to study the effect of postharvest treatment with sodium nitroprusside (50, 100 and 150 µM) on the storage life, quality attributes, bioactive composition and antioxidant enzyme contents of ‘Umran’ ber fruit. The treated fruit were stored for 28 days to investigate the effects of sodium nitroprusside after 7 days of cold storage at 7.5°C and 90–95% RH. It was found that fruit treated with 100 μM sodium nitroprusside experienced lower fruit weight loss and spoilage, maintained fruit firmness, and had a higher sensory quality, phenolic content, carotenoid content, soluble solids content, sugar content, ascorbic acid and antioxidant activity than the control. Furthermore, the activities of the cell wall degrading enzymes polygalacturonase, polyphenol oxidase, pectin methyl esterase and catalase were lower, while the activities of superoxide dismutase and peroxidase enzymes were higher in the treated fruit. Therefore, treatment with 100 μM sodium nitroprusside shows high potential for improving the storage life and maintaining the quality attributes of ber fruit for up to 21 days under cold storage.

Carotenoid and Phenolic Compositions and Antioxidant Activity of 23 Cultivars of Corn Grain and Corn Husk Extract.

As a byproduct of corn processing, corn husk is usually burned or disposed of. To make a better use of corn husk, its bioactive components need to be further explored. In this work, the carotenoids and phenolics of the extracts from the corn grain and corn husk of 15 different yellow corn and 8 different waxy corn were identified and quantified, and their antioxidant activities were assessed. The results showed many considerable variations in carotenoid contents. Four types of carotenoids were observed only in both yellow corn and black waxy corn. The highest lutein and zeaxanthin contents were both observed in yellow corn husks. Lutein dominates in yellow corn, ranging from 494.5 μg/g dw to 2870.8 μg/g dw, which is followed by zeaxanthin, ranging from 63.0 μg/g dw to 360.2 μg/g dw, and finally β-cryptoxanthin and β-carotene. The total content of polyphenols (TPC) and flavonoids (TFC) of the husk from 13 yellow corn cultivars, as well as the TPC of husk from 8 waxy corn cultivars, were all higher than those of their corn grain, with the highest TPC found in waxy corn husk. Additionally, a total of 20 phenolic compounds were identified, and ferulic acid showed the highest content and reached 1101.9 µg/g dw in a waxy corn husk. The average antioxidant activity of a waxy corn husk was 25-65% higher than that of a yellow corn husk, and the highest values were observed in the husk of the waxy corn cultivar Huhong 1. These results suggested that corn husk is a rich source of lutein and phenolics and provided excellent cultivars as a reference for functional food products in agriculture and the food industry.

Nutrient Composition of Arugula Leafy Greens Following Application of Ascorbic Acid Foliar Sprays

Agronomic biofortification of vitamin C is a promising strategy to address vitamin C deficiencies in populations that lack access to diverse and nutritious diets. Different application methods can improve the vitamin C content in various crops; however, foliar application of ascorbic acid (AA) solutions has been under-explored. To determine if spray concentration, number of applications, and day of harvest would affect vitamin C in arugula leafy greens, foliar sprays consisting of 100 ppm and 200 ppm of AA and deionized (DI) water control were applied. Treatment application was initiated during the baby-leaf stage and subjected to a total of three sprays over the course of the experiment, followed by harvest at two days and four days after spraying (DAS). The harvested plants were measured for fresh and dry biomass and analyzed for vitamin C content, mineral composition, chlorophyll levels, and carotenoid content. The results of this study demonstrated a notably elevated total vitamin C concentration (p = 0.0002) and AA content (p = 0.02) in arugula leaves treated with a 200 ppm AA spray following the third application and harvested at 4 DAS. Additionally, the AA application improved the fresh and dry weight of leafy greens but did not exhibit any significant variances regarding the mineral composition of P, K, Ca, Mg, S, B, Zn, Mn, and Fe. Alternatively, AA foliar sprays reduced Cu content in leaves suggesting that AA reduced Cu accumulation in arugula leafy greens. In summary, the findings of this study establish that the foliar application of 200 ppm AA is an effective approach for increasing the vitamin C content in arugula leafy greens while improving the plant’s biomass, mineral composition, and stress responses. These biofortified arugula leafy greens exhibit the potential to offer plant protection against environmental stresses and a more consistent supply of vitamin C to humans upon consumption.

Physicochemical quality retention of ‘Sucrier’ bananas (Musa acuminata AA group cv. ‘Kluai Khai’) by jicama starch-based postharvest treatment

The objective of this research was to develop a new type of edible coating using jicama starch (JS) in order to control the postharvest deterioration of ‘Sucrier’ bananas (Musa acuminata AA group cv. ‘Kluai Khai’) during the ripening process in ambient condition (25 ± 1 °C, 85-90 % RH). The preliminary experiment was carried out to investigate the impact of JS concentration (0, 2.5, 5.0, and 7.5 % w/v) on the postharvest quality of bananas. The application of JS demonstrated a delay in banana ripening, including color development, weight loss, and fruit firmness. Within the JS-treated banana groups, 5.0 % treated bananas displayed higher firmness compared to the other groups. Therefore, a validation experiment was conducted to verify the subsequent physicochemical alterations in bananas after subjecting bananas to 5.0 % JS coating in comparison to non-treated bananas during storage at ambient condition. The JS treatment maintained the color and visual appearance by minimizing the formation of malondialdehyde content and electrical conductivity during storage. Furthermore, it resulted in a delay in the increases in total soluble solid, titratable acidity, BrimA, and total carotenoid concentrations in the pulp. Nevertheless, the ascorbic acid and phenolic contents and 2,2-diphenyl-2-picrylhydrazyl scavenging activity of the control samples were likely to be higher than those of the treated bananas, whereas the ferric reducing antioxidant potential of both control and treated bananas showed a comparable trend throughout storage. The outcomes demonstrate that the utilization of JS is an effective approach for improving the overall storage capacity of ‘Sucrier’ bananas.

Discovering a novel glycosyltransferase gene CmUGT1 enhances main metabolites production of Cordyceps militaris.

Cordyceps militaris is a filamentous fungus used for both medicinal and culinary purposes. It exhibits a wide range of pharmacological activities due to its valuable contents of cordycepin, polysaccharides, carotenoids, terpenoids and other metabolites. However, C. militaris strains are highly susceptible to irreversible degradation in agricultural production, which is often manifested as a prolonged color change period and a significant decrease in the production of secondary metabolites. UDP-glycosyltransferases are an important enzyme family that participates in the synthesis of terpenoids by performing the glycosylation of key residues of enzymes or molecules. However, few studies have focused on its effect on the regulation of metabolite production in C. militaris. Therefore, in this study, we performed transcriptome analysis across four different developmental stages of C. militaris to target the putative glycosyltransferase gene CmUGT1, which plays important roles in metabolite production. We further constructed and screened a CmUGT1-overexpressing strain by Agrobacterium tumefaciens-mediated infestation of C. militaris spores. The major metabolite production of the wild-type and CmUGT1-overexpressing C. militaris strains was determined after short-term shake-flask cultivation of mycelia. The results showed that the yields of carotenoids and polysaccharides in the mycelia of the CmUGT1-overexpressing strains were 3.8 and 3.4 times greater than those in the mycelia of the wild type, respectively (p < 0.01). The levels of intracellular and extracellular cordycepin produced by the overexpression strain were 4.4 and 8.0 times greater than those produced by the wild-type strain (p < 0.01). This suggests that the overexpression of CmUGT1 in C. militaris enhances the synthesis activities of the main enzymes related to metabolite production, which provides a guide for obtaining excellent recombinant strains of C. militaris.

Physiological response of microalga Dunaliella parva when treated with MeJA, GA3.

DpAP2 is a transcription factor regulating carotenoid biosynthesis pathway. It was speculated that MeJA significantly decreased expression of DpAP2 gene, then the decreasing DpAP2 expression significantly inhibited expression of some key enzyme genes such as PSY, PDS and GGPS in carotenoid biosynthesis pathway. In contrast, it was speculated that GA3 significantly increased expression of DpAP2 gene, then the increasing DpAP2 expression significantly increased expression of some key enzyme genes such as PDS and GGPS in carotenoid biosynthesis pathway. To increase the content of carotenoid, we evaluated the effect of DpAP2 overexpression on carotenoid accumulation in D. parva. Transgenic D. parva showed a higher carotenoid content (3.18 mg/g DW) compared with control group (2.13 mg/g DW) at 9 d. The dosage effects of exogenous hormones MeJA and GA3 were found in D. parva cells treated with different concentrations of MeJA (10, 20, 50, 100 μM) and GA3 (10, 20, 50, 100 μM). The high concentrations of MeJA (10-100 μM) inhibited the accumulation of carotenoid, and the relative expression of DpAP2, PSY, PDS and GGPS decreased significantly. On the contrary, the relative expression of DpAP2, PDS and GGPS increased significantly when D. parva was treated with 10, 20, 50 and 100 μM GA3, which promoted the biosynthesis of carotenoid. Therefore, we inferred that there was a hierarchical regulation from hormone, transcription factor, key enzyme gene to carotenoid accumulation in carotenoid biosynthesis. Carotenoid biosynthesis was enhanced by DpAP2 overexpression (1.4930 fold of control) and exogenous substances such as GA3 (1.5889 fold of control), which laid a foundation for massive accumulation of carotenoids in microalgae. In the future, further studies were required to demonstrate the complex regulatory network.

How does finishing duration on lucerne pasture influence the muscle and fat spectro-colorimetric properties and dorsal fat firmness in lambs?

There are a number of differences in the meat and carcass quality traits between pasture-raised and concentrate-raised lambs that may further be used to trace back the diet, but the extent to which these differences are modulated by pasture-finishing duration is unknown. In this study, we investigated the changes in longissimus thoracis et lumborum muscle and fat spectrocolorimetric properties, and dorsal fat firmness, in lambs switched from a stall-fed concentrate-based diet to grazing on lucerne for various durations (0, 21, 42, 63 days) pre-slaughter. Stall-fed lambs from the different treatment groups were managed in a single group and lucerne pasture-finished lambs from the different treatment groups also co-grazed in a single group. The level of concentrate fed to stall-fed lambs was adjusted to maintain a similar mean pattern of growth between lucerne pasture-fed and stall-fed lambs. The trial used a total of 141 lambs over two successive years. Dorsal fat was firmer in lambs finished on lucerne pasture, even for the shortest finishing duration (21 days), the difference being of commercial importance. Dorsal fat colour and carotenoid content showed changes at 21 days on lucerne pasture but did not change further for longer lucerne pasture-finishing durations. In contrast, perirenal fat lightness, yellowness, chroma and carotenoid content showed changes at 21 days on lucerne pasture and increased consistently with lucerne pasture-finishing duration. Although these changes in fat spectrocolorimetric properties were not, or barely, visible to the naked eye, they could be of interest for authenticating the duration of lucerne pasture-finishing. Muscle redness increased consistently with the duration of lucerne pasture-finishing, the change becoming significant from 42 days on lucerne pasture and being visible to the naked eye. We observed a consistent decrease in muscle hue angle and perirenal fat redness and a consistent increase in perirenal fat hue angle with lucerne pasture-finishing duration, but these changes only became significant from 63 days on lucerne pasture. The pattern of change in the lamb carcass and meat quality traits measured according to lucerne pasture-finishing duration therefore varied between the tissues and quality traits.

Physicochemical characteristics of cold-pressed blackcurrant-, strawberry-, and raspberry seed oils during storage and its influence on thermo-oxidative stability

The storage characteristics of cold-pressed blackcurrant-, strawberry- and raspberry seed oils and the factors influencing thermo-oxidative stability during storage were determined. It was established that throughout one year there were no significant (p ≤ 0.05) changes of thermo-oxidative stability (OIT at 120 and 140 °C) and fatty acid composition in all berry seed oils (BSO), despite a minor reduction in antioxidant activity (DPPH radical scavenging) and tocopherol content, and an increase in acid value, p-anisidine value, and K232, K268 values. Pigment degradation became noticeable after 6 months, resulting from a decrease in chlorophyll and carotenoid content, and observed in changes of colour parameters (angle hue, chroma, ΔE). The study also showed that many compositional factors play an important role in maintaining the thermo-oxidative stability of berry seed oils at a constant level over a period of one year, among which the most significant parameters influencing OIT values were the content of fatty acid c18:1, tocopherols and carotenoids, as revealed by the multiple linear regression analysis (MLR).