Higher Concentrations Of Lutein Research Articles

Exploring freshwater microalgal strains for Omega-3 polyunsaturated fatty acids and carotenoids from the Ganges River in India

Microalgae, increasingly recognized as a cost-effective reservoir of natural compounds. Their extensive application in nutraceuticals, and pharmaceuticals industry are making them mercantile worthy. This study delves into the realm of bioprospecting freshwater microalgae with focus on extracting high-value products, specifically omega-3 polyunsaturated fatty acids and carotenoids. Freshwater-derived microalgal strains were isolated from Ganges River and refined, and grown in BG-11 culture medium. Microscopic examination was used to screen these microalgae based on morphology. Subsequently, the biochemical properties of the selected microalgal strains were investigated. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two crucial omega-3 polyunsaturated fatty acids, were identified in significant quantities in Chlorella variabilis (3.6±1.32%; 2.7±0.13%) and Monoraphidium contortum (2.2±0.36%; 3.2±0.2%). Moreover, the investigation also focused on carotenoids; lutein and astaxanthin. The findings indicated a high concentration of lutein in Chlorella variabilis (4.5 mg g−1), while Monoraphidium contortum exhibited abundant levels of astaxanthin (5.9 mg g−1). These research findings demonstrate the promising capacity of the isolated microalgal strains to yield valuable bioactive compounds.

Effect of genotype on performance, vitamin and carotenoid deposition, oxidative stability, fatty acid profile and sensory characteristics in cockerels housed on litter and in mobile boxes on pasture

The study evaluated the effect of housing system and genotype on performance and breast meat quality in 540 cockerels. Three genotypes of cockerels differing in growth intensity (slow-growing ISA Dual, medium-growing Hubbard JA757 and fast-growing Ross 308) and two housing systems (litter and mobile box on pasture) were compared. The significantly lowest feed conversion (p < .001) was recorded for Ross 308 cockerels housed on litter, while ISA Dual cockerels from mobile boxes had a 74% higher conversion ratio. The highest concentrations of lutein (p = .043) and α-tocopherol (p = .024) in breast meat were found in the cockerels from mobile boxes of genotypes ISA Dual and Ross 308, respectively. Meat stored for five days showed the highest oxidative stability of fat (p = .001) in slow- and medium-growing cockerels housed on pasture. The ISA Dual genotype housed both on litter and on pasture and the Hubbard JA757 genotype from mobile boxes had the highest proportion of polyunsaturated fatty acids in the meat (p < .001). The lowest n6/n3 fatty acid ratio (p = .045) and thrombogenic index (p < .001) and the highest hypocholesterolaemic/hypercholesterolaemic index (p < .001) were recorded in slow-growing chickens with access to pasture. The meat of cockerels fattened on litter was considered more fragrant (p = .013), more tender (p < .001), juicier (p < .001) and overall more acceptable (p = .001). It can be concluded that the ISA Dual genotype showed the highest willingness to graze compared to Hubbard JA757 and Ross 308 cockerels and made the best use of the benefits of pasture fattening, which was reflected in the high quality of the meat. The meat of conventionally housed cockerels was sensorially evaluated as better. Highlights The ISA Dual genotype showed the highest willingness to graze, which was reflected in the higher content of health-promoting substances in meat. The more frequent use of slow-growing cockerels for the purpose of fattening will be hindered by lower performance of the cockerels and low level of meat tenderness.

The Antioxidant and Anti-Inflammatory Effects of the Main Carotenoids from Tomatoes via Nrf2 and NF-κB Signaling Pathways.

Oxidative stress and inflammation are crucial factors in the development of cardiovascular diseases. In previous research, the oxidative stress and inflammation models have frequently been explored independently. In the current study, we investigated the antioxidant and anti-inflammatory effects of tomato extract and its two main carotenoids (lutein and lycopene) with various concentrations using a rat cardiomyocyte model of co-existing oxidative stress and persistent chronic inflammation. It was discovered that the antioxidant effects of 0.5-5 μM lutein, 0.5-5 μM lycopene, and 50-200 μg/mL tomato extract increased in a dose-dependent manner. However, the pro-oxidation effects emerged by measuring the antioxidant-related indices, including the levels of ROS, SOD, and GPX in H9c2 cells as concentrations exceeded those mentioned above. The anti-inflammatory effects of lutein, lycopene, and tomato extract were simultaneously strengthened with higher concentrations, potentially due to the suppression of the NF-κB signaling pathway. Furthermore, high concentrations of lutein, lycopene, and tomato extract potentially regulated Nrf2/HO-1 and NF-κB signaling pathways dependent on TGF-1β and IL-10 to demonstrate high concentrations of pro-oxidation and anti-inflammation effects. Our findings indicate that the dose-effect regulatory mechanisms of antioxidant and anti-inflammatory properties among lutein, lycopene, and tomato extract will be advantageous in developing more effective therapeutic strategies to prevent cardiovascular diseases.

Extraction and analysis of lutein and antioxidant activities from red spinach’s root, stem, and leaf

Red spinach is leafy vegetable containing a high concentration of carotenoid such as lutein, which shows high benefits in anti-cancer and antioxidant to protect eye health from oxidative stress caused by cataracts and age-related macular degeneration (AMD). Because of the potential activity against eye disease, extraction to obtain high concentration of lutein from this vegetable is urgently needed. Generally, lutein from leafy vegetables extracted from leaf. This study presents extraction and analysis lutein and antioxidant activities from all parts of the red spinach, such as the root, stem, and leaf. The extraction using hexane solvent. The result showed that the lutein content in root, stem, and leaf of red spinach by HPLC analysis was almost equal for all parts, 62.63 ppm for the root, 63.30 ppm for the stem, and 62.63 ppm for the leaf. In addition, spinach leaf displayed weak antioxidant activities due to a low IC50 value of 208.64 ppm. In contrast, spinach’s root and stem showed very weak antioxidant activities due to high value of IC50 of 463.19 ppm and 428.67 ppm. In conclusion, spinach’s leaf, the root and stem are good sources of lutein because of their high lutein content, but the antioxidant activity of spinach’s leaf is categorized as weak, and spinach’s root and stem are categorized as very weak in their extract.

Concentrations of retinol and carotenoids in Jersey milk during different seasons and possible application of the colour parameter as an indicator of milk carotenoid content

The aim of this study was to determine concentrations of retinol, β-carotene, lutein and zeaxanthin in Jersey milk during different seasons and their correlation with milk colour parameters. During a sixmonths period the Jersey cows (n=77) were kept free-stall and fed with total mixed ratio (TMR; farm season), for the next three months the cows were kept for four hours on pasture and the rest of the day free-stall fed with TMR (transition season), and for the remaining three months they were kept predominantly on pasture (grazing season). A bulk milk samples (200 mL) were collected during the last week of each month in the period between May 2018 and April 2019. Retinol and carotenoids concentrations in cow milk were quantified using high performance liquid chromatography, while milk chemical composition was analysed by a MilkoScan FT 120 infra-red analyser. The season significantly (P&amp;lt;0.05) affected chemical composition of milk, and the highest (P&amp;lt;0.05) content of milk fat, protein and non-fat dry matter was found during the farm season. Retinol, β-carotene, lutein and zeaxanthin concentrations (μg/100 mL) were as follows: 2.56±0.29, 4.15±0.27, 4.43±0.40 and 0.97±0.04. Lutein and retinol concentrations in Jersey milk were affected (P&amp;lt;0.05) by the season. The highest lutein concentration was found during the grazing season, while the farm season yielded the highest retinol concentration. Moderate and positive correlations (P&amp;lt;0.05) were found between β-carotene and lutein concentrations and colour parameter b*, resulting in a more intense yellow colour i.e. high values of colour parameter b*. The obtained results suggest that milk colour could be used to estimate carotenoid concentrations in milk.

Application of the central composite design and response surface methodology for investigation of induction time, conjugated diene, conjugated triene and trans fatty acid content of corn oil enriched with carotenoids

The central composite design technique was used to investigation of induction time, conjugated diene, conjugated triene and trans fatty acid content of corn oil enriched with lutein, β-carotene and lycopene in this study. The levels of lutein and β-carotene and were between 0 and 94 mg/kg, while lycopene levels was 0–49.56 mg/kg. Oil samples with and without lutein, β-carotene and lycopene were prepared according to central composite design. The influence of these three independent variables on the four dependent variables such as time, conjugated diene and conjugated triene and trans fatty acid content was evaluated using a reduced cubic model. The each independent variable was effective on the induction time, conjugated diene, conjugated triene and trans fatty acid content of corn oil. The positive effect on the induction time was observed high concentrations of lutein and lycopene concentrations. Lutein, β-carotene and lycopene had a significant effect on conjugated diene, conjugated triene and trans fatty acid content. The desirability function and the 3D plots suggested that optimum parameters were lutein concentration of 19 mg/kg, β-carotene concentration of 19 mg/kg and lycopene concentration of 12.5 mg/kg as optimum parameters for maximum induction time and the minimum formation of conjugated diene, conjugated triene and trans fatty acid species.

A Comparison of Vitamin and Lutein Concentrations in Breast Milk from Four Asian Countries

Vitamins are the essential elements for human life and, particularly, for infant health. Human milk is the best source of nutrients for newborns, however, the information of vitamins in Asian maternal milk is still limited. In this study, we have collected 580 Asian maternal milk samples from Korea (n = 254), China (n = 137), Pakistan (n = 92), and Vietnam (n = 97). The vitamin concentrations, including vitamin B-groups (8 vitamins), fat-soluble vitamin (retinol, D, E, K) and lutein in the breast milk of were investigated. The concentration of thiamin (B1), biotin (B7), and folic acid (B9) in mother’s milk of four countries were not considerably different, while riboflavin (B2), pantothenic acid (B5), and pyridoxine (B6) level in Vietnam samples were significantly lower than those in other countries. In contrast, retinol (A) and tocopherol (E) were found to be higher levels in Vietnamese maternal milk. Korean and Chinese maternal milk had low concentrations of retinol that may cause vitamin A deficiency in children. However, Chinese mother’s milk was distinguished with a high concentration of lutein. Pakistani mother’s milk was observed as having a significant problem of folic acid (B9) deficiency. Regardless of the country, vitamin B12, K, and D did not seem to be provided sufficiently through maternal milk. The moderate positive correlations were found between vitamin concentrations in each country and the pooled sample. The data obtained in this study were able to provide vital information to assess the nutritional status of breast milk in Asian countries and contributed to the efforts of ensuring the best nutrition for Asian children.

Outdoor Large-Scale Cultivation of the Acidophilic Microalga Coccomyxa onubensis in a Vertical Close Photobioreactor for Lutein Production

The large-scale biomass production is an essential step in the biotechnological applications of microalgae. Coccomyxa onubensis is an acidophilic microalga isolated from the highly acidic waters of Río Tinto (province of Huelva, Spain) and has been shown to accumulate a high concentration of lutein (9.7 mg g−1dw), a valuable antioxidant, when grown at laboratory-scale. A productivity of 0.14 g L−1 d−1 was obtained by growing the microalga under outdoor conditions in an 800 L tubular photobioreactor. The results show a stable biomass production for at least one month and with a lutein content of 10 mg g−1dw, at pH values in the range 2.5–3.0 and temperature in the range 10–25 °C. Culture density, temperature, and CO2 availability in highly acidic medium are rate-limiting conditions for the microalgal growth. These aspects are discussed in this paper in order to improve the outdoor culture conditions for competitive applications of C. onubensis.

Pilot-scale production of lutein using Chlorella vulgaris

Lutein is a carotenoid pigment which has applications in the food and nutraceutical sectors, both for its use as a colourant and for its applications as a nutraceutical. Microalgae are a promising source of lutein, however to meet market demand there is a need to develop technologies which can used for large-scale production. The effect of process conditions at a 5L scale were quantified, it was found that at low light intensities (160μmol photons m−2 s−1) the measured specific lutein concentration was 7.4±2.1mg g−1 which was greater than the concentration of 3.1±1.1mg g−1 obtained at higher (440μmol photons m−2 s−1) light intensities. Supplementation of the medium with nitrate led to significant increases in the maximum specific lutein concentration (10.4±5.5mg g−1) compared to medium without nitrate addition (4.3±2.9mg g−1). These conclusions were used to scale-up the process using 50L bubble column photo-bioreactors, it was found that the productivity was maximised (1.6mgL−1 day−1) using an air flow-rate of 1 vvm and 24h lighting. Finally, it was found that the process could be operated on a semi-continuous basis for 32 days, achieving high lutein concentrations (15–20mgL−1) with the performance of the system being consistent for this duration. Results from this work have clear application in the development of large-scale systems for the microalgal production of lutein.

Associations Between Serum Lutein and Human Gut Microbiota (P02-004-19)

ObjectivesLutein is a carotenoid found in green leafy vegetables, avocados, and eggs, and is purported to have protective effects against age-related macular degeneration (AMD) as well as benefits for visual and cognitive health. Recent studies have indicated significant variation in serum lutein among individuals and that gastrointestinal (GI) microbial profile may potentially contribute to lutein status. However, the extent to which the GI microbiota contribute to lutein is unclear. The current study aimed to determine GI microbial predictors of serum lutein in a healthy young adult population. MethodsAmong adults ages 25–45 years (N = 105), venous blood was collected following a 10-hour fast. Serum lutein was determined using HPLC. Fecal DNA was extracted and the V4 region of the 16S rRNA gene was amplified. Amplicon sequence variants were assigned using the GreenGenes 13-8 database and DADA2, followed by analysis in QIIME2 and LDA Effect Size (LEfSe). Participants underwent DXA scan for whole body % fat (%Fat) and completed a 7-day food record to assess lutein consumption. Demographic information on participant’s age and sex was also assessed and included in the statistical models. ResultsFour genera (Dialister, Ruminococcus, Gemmiger, and Phascolarctobacterium) and two species (Bacteroides eggerthii, Ruminococcus torques) were different between individuals in the highest and lowest quartiles of serum lutein. The genera Ruminococcus (Rho = –0.24, P = 0.02) and Phascolarctobacterium (Rho = –0.21, P = 0.03) and species R. torques (Rho = –0.35, P < 0.001) were inversely related to serum lutein. Linear regression modelling, adjusted for age, sex, %Fat, and dietary lutein, revealed that R. torques was the only significant predictor of serum lutein concentrations, accounting for 8.4% of the variance. ConclusionsOur results reveal that individuals with lower serum lutein concentrations have a higher relative abundance of R. torques than those with higher lutein concentrations. As R. torques has been shown to be elevated in those with AMD, it is possible the relationship between this microbe and lutein is evident earlier in adulthood. However, further dietary intervention trials are warranted to clarify the relations among R. torques and serum lutein concentrations. Funding SourcesThis work was supported by funds provided by the Department of Kinesiology and Community Health at the University of Illinois and the USDA National Institute of Food and Agriculture, Hatch Project 1009249. Partial support was also provided by the Hass Avocado Board.

Carotenoid Content and Composition in 20 Medicinal Plant Species of Traditional Malay Midwifery Postnatal Bath

Today in Malay community, midwifery traditional knowledge of herbal medicine has disappeared and extinct. The facts are Malay midwives are becoming rare and the more crucial is medicinal plants are over-harvested. The aim of this research is to identify and investigate the active pharmaceutical ingredients content in 20 selected species used in the Malay traditional bath. There is a solid need to analyse the potential of these natural bioactive compounds, particularly carotenoids to be fully utilised and commercialised especially in halal market and health advantages. Through High performance liquid chromatography (HPLC) analysis, all 20 species were found to have at least four individual carotenoid pigments with a relatively high concentration of lutein and β-carotene and lower concentrations of zeaxanthin. Strobilanthes crispus (Pecah Kaca) leaf was detected to have the highest total carotenoid content (1546.80±283.45 μg/g DW)while Psidium guajava (Jambu Batu) shoot has the lowest total carotenoid content (112.9±82.2 μg/g DW). The significant outcome of the research was a new findings of new natural bioactive compound sources as health promoting agents which covers not only the Shariah requirement, but also safety aspects. Moreover, it will preserve the traditional knowledge of Malay traditional bath practices.

Effect of green juice and their bioactive compounds on genotoxicity induced by alkylating agents in mice

ABSTRACTKale juice (Brassica oleracea L. var. acephala D.C.) is a reliable source of dietary carotenoids and typically contains the highest concentrations of lutein (LT) and beta-carotene (BC) among green leafy vegetables. As a result of their antioxidant properties, dietary carotenoids are postulated to decrease the risk of disease occurrence, particularly certain cancers. The present study aimed to (1) examine the genotoxic and antigenotoxic activity of natural and commercially available juices derived from Brassica oleracea and (2) assess influence of LT or BC against DNA damage induced by alkylating agents such as methyl methanesulfonate (MS) or cyclophosphamide (CP) in vivo in mice. Male Swiss mice were divided into groups of 6 animals, which were treated with water, natural, or commercial Brassica oleraceae juices (kale), LT, BC, MMS, or CP. After treatment, DNA damage was determined in peripheral blood lymphocytes using the comet assay. Results demonstrated that none of the Brassica oleraceae juices or carotenoids produced genotoxic effects. In all examined cell types, kale juices or carotenoids inhibited DNA damage induced by MMS or CP administered either pre- or posttreatment by 50 and 20%, respectively. Under our experimental conditions, kale leaf juices alone exerted no marked genotoxic or clastogenic effects. However, a significant decrease in DNA damage induced by MMS or CP was noted. This effect was most pronounced in groups that received juices, rather than carotenoids, suggesting that the synergy among constituents present in the food matrix may be more beneficial than the action of single compounds. Data suggest that the antigenotoxic properties of kale juices may be of therapeutic importance.

Effect of Carotenoid Supplemented Formula on Carotenoid Bioaccumulation in Tissues of Infant Rhesus Macaques: A Pilot Study Focused on Lutein.

Lutein is the predominant carotenoid in the developing primate brain and retina, and may have important functional roles. However, its bioaccumulation pattern during early development is not understood. In this pilot study, we investigated whether carotenoid supplementation of infant formula enhanced lutein tissue deposition in infant rhesus macaques. Monkeys were initially breastfed; from 1 to 3 months of age they were fed either a formula supplemented with lutein, zeaxanthin, β-carotene and lycopene, or a control formula with low levels of these carotenoids, for 4 months (n = 2/group). All samples were analyzed by high pressure liquid chromatography (HPLC). Final serum lutein in the supplemented group was 5 times higher than in the unsupplemented group. All brain regions examined showed a selective increase in lutein deposition in the supplemented infants. Lutein differentially accumulated across brain regions, with highest amounts in occipital cortex in both groups. β-carotene accumulated, but zeaxanthin and lycopene were undetectable in any brain region. Supplemented infants had higher lutein concentrations in peripheral retina but not in macular retina. Among adipose sites, abdominal subcutaneous adipose tissue exhibited the highest lutein level and was 3-fold higher in the supplemented infants. The supplemented formula enhanced carotenoid deposition in several other tissues. In rhesus infants, increased intake of carotenoids from formula enhanced their deposition in serum and numerous tissues and selectively increased lutein in multiple brain regions.

Enhancement of Protein and Pigment Content in Two Chlorella Species Cultivated on Industrial Process Water

Chlorella pyrenoidosa and Chlorella vulgaris were cultivated in pre-gasified industrial process water with high concentration of ammonia representing effluent from a local biogas plant. The study aimed to investigate the effects of growth media and cultivation duration on the nutritional composition of biomass. Variations in proteins, lipid, fatty acid composition, amino acids, tocopherols, and pigments were studied. Both species grew well in industrial process water. The contents of proteins were affected significantly by the growth media and cultivation duration. Microalga Chlorella pyrenoidosa produced the highest concentrations of protein (65.2% ± 1.30% DW) while Chlorella vulgaris accumulated extremely high concentrations of lutein and chlorophylls (7.14 ± 0.66 mg/g DW and 32.4 ± 1.77 mg/g DW, respectively). Cultivation of Chlorella species in industrial process water is an environmentally friendly, sustainable bioremediation method with added value biomass production and resource valorization, since the resulting biomass also presented a good source of proteins, amino acids, and carotenoids for potential use in aquaculture feed industry.

Genotypic variability of carotenoids in traditional tomato cultivars

Traditional varieties constitute a wide source of genetic variation that can be used per se or to obtain new cultivars with high consumer appeal and nutritional value. This work focuses on the carotenoid and chlorophyll profiles and contents of 53 traditional tomato cultivars, paying particular attention to compounds with recognized health-promoting properties. The study includes fruits with different shapes (oblate, slightly flattened, rounded, heart-shaped, long oblong and pyriform), colors (yellow, pink and red) and sizes (very small to very large). In addition, black colored tomato fruits with yellow, pink or red background color were studied. The highest concentrations of lycopene, β-carotene, phytoene and phytofluene were found in pink and red tomatoes, while the highest concentrations of lutein, violaxanthin, neoxanthin and chlorophylls were found in fruits with a dark coloration, regardless of their background coloration. Finally, the highest concentrations of the studied compounds as a whole (except β-carotene) were found in red- and pink-black varieties. Findings will hopefully contribute to recovering many tomato traditional varieties for use, directly in the field or as donor parents for breeding programs, to increase the nutraceutical properties of commercial varieties.

Plasma Carotenoids Are Inversely Associated With Dementia Risk in an Elderly French Cohort.

Although intake of fruits and vegetables has been associated with a decreased risk of dementia, studies focusing on nutrients underlying this association are lacking. Our objective was to analyze the relation between plasma carotenoids and the risk of dementia and Alzheimer's disease (AD) in French elderly community dwellers. The study population consisted of 1,092 nondemented older participants, from the Three-City-Bordeaux cohort followed for up to 10 years (range: 1.8-10.8 years, median: 9.5 years). Dementia and AD were diagnosed by a committee of neurologists. The concentration of plasma carotenoids (beta-carotene, alpha-carotene, lycopene, lutein, zeaxanthin, and beta-cryptoxanthin) was determined at baseline. Longitudinal analyses of the association between each plasma carotenoid, either crude or expressed as a ratio to plasma lipids (total cholesterol + triglycerides), and the risk of dementia or AD were performed by multivariate Cox models. During follow-up, 199 dementia cases, including 132 AD, occurred. After adjustment for sociodemographic data, diet quality, and clinical variables, including baseline cognitive performances, only higher lutein concentration, considered as a function of plasma lipids, was consistently significantly associated with a decreased risk of all-cause dementia and AD (hazard ratio = 0.808, 95% confidence interval = 0.671-0.973, p = .024 and hazard ratio = 0.759, 95% confidence interval = 0.600-0.960, p = .021, respectively for +1 SD). This large cohort of older participants suggests that maintaining higher concentrations of lutein in respect to plasma lipids may moderately decrease the risk of dementia and AD.

Selection for soyabeans with high and environmentally stable lutein concentrations

Lutein has significant nutritional benefits for human health. Therefore, enhancing soybean lutein concentrations is an important breeding objective. However, selection for soybeans with high and environmentally stable lutein concentrations has been limited. The objectives of this study were to select soybeans with high seed lutein concentrations and to determine the stability of lutein concentrations across environments. A total of 314 genotypes were screened and 18 genotypes with high lutein concentrations and five genotypes with low lutein concentrations were selected for further examination. These 23 genotypes and two check varieties were evaluated under six environments (two planting dates for 2 years at one location and two planting dates for 1 year at another location). Lutein concentrations were influenced by genotype, environment and genotype × environment interactions. Genotypes with late maturity and low lutein concentrations were more stable than those with early maturity and high concentrations. Early (May) planting resulted in greater lutein concentrations than late (June) planting. Among the genotypes evaluated, PI603423B (7.7 μg/g) and PI89772 (5.8 μg/g) had the greatest mean lutein concentrations and exhibited medium and high stability across the six environments, respectively. Thus, these genotypes may be useful for breeding soybeans with high and stable seed lutein concentrations.

Structure and function characterization of the phytoene desaturase related to the lutein biosynthesis in Chlorella protothecoides CS-41

Phytoene desaturase is the key enzyme involved in the biosynthesis pathway of lutein. The unicellular microalga, Chlorella protothecoides CS-41, had been selected for the heterotrophic production of high concentrations of lutein. In this study, a cDNA copy of the pds gene from C. protothecoides was obtained using the rapid amplification of cDNA ends (RACE) technique. Phylogenetic analysis of the deduced amino acid sequence revealed that the phytoene desaturases derived from the algal family. Expression of the pds gene in Escherichia coli produced a single protein of 61 kDa. The PDS activity of the expressed protein was confirmed by the production of ζ-carotene as the result from the action of the enzyme's desaturation activity, which was identified by high-performance liquid chromatography and heterologous complementation analysis. Using random and site-directed mutagenesis, a single amino acid mutation (N144D) was identified and confirmed. This mutant encodes an inactive enzyme, which implies that amino acid 144 is crutial to the activity of the PDS enzyme. Therefore, by gene cloning and expression in prokaryotic cells, the gene for ζ-carotene production or as part of the biosynthetic pathway of lutein had been characterized from Chlorella protothecoides CS-41.

Physiological response and photoacclimation capacity of Caulerpa prolifera (Forsskål) J.V. Lamouroux and Cymodocea nodosa (Ucria) Ascherson meadows in the Mar Menor lagoon (SE Spain)

The macroalga Caulerpa prolifera colonized the Mar Menor coastal lagoon after the enlargement of the main inlet in 1972, coexisting now with the previous Cymodocea nodosa meadows. The physiological response and the photoacclimation capacity of both species were studied. For this purpose in vivo chlorophyll a fluorescence, photoprotective mechanisms and oxidative stress were measured in both species in summer 2010 and exposure-recovery experiments were conducted to determine the acclimation capacity of both species. The results suggest that C. prolifera behaves as a shade-adapted species with a low photoprotective capacity, light being one of the main factors governing its distribution in the lagoon. The high photosynthetic capacity and lack of photoinhibition found in C. nodosa suggest that this species is highly photoprotected. It also possesses a high concentration of lutein and a high de-epoxidation degree, related to a much higher NPQmax value.

Response to photoxidative stress induced by cold in japonica rice is genotype dependent

Two japonica rice genotypes, INIA Tacuarí and L2825CA, were analyzed for tolerance to low temperature during early vegetative growth. Effect on photosynthesis, energy dissipation, pigment content, xanthophyll-cycle pool conversion, hydrogen peroxide accumulation, oxidative damage and antioxidant enzyme activities were determined to better understand potential mechanisms for cold tolerance. Photoinhibition was measured using chlorophyll fluorescence and oxidative damage by lipid peroxidation and electrolyte leakage. Both genotypes were demonstrated to be cold tolerant which was consistent with their reduced levels of photoinhibition and oxidative damage compared with a cold-sensitive genotype during chilling stress. The strategy for cold tolerance differed between the two genotypes, and involved different mechanisms for disposal of excess energy. The presence of high lutein concentrations and the existence of active non-harmful energy dissipation processes through the xanthophyll cycle appeared to be responsible for chilling tolerance in INIA Tacuarí. On the other hand, increased cold tolerance of L2825CA relative to INIA Tacuarí was related to the higher constitutive superoxide dismutase (SOD, EC 1.15.1.1), ascorbate peroxidase (APX, EC 1.11.1.11) and catalase (CAT, EC 1.11.1.6).