Carotenoids Analysis Service

What Is Carotenoids

Carotenoids, found in a wide range of fruits and vegetables, contribute to their vibrant colors, including shades of orange, yellow, and bright red. These pigments are crucial for plant health and serve as auxiliary chloroplast pigments during photosynthesis, safeguarding chlorophyll from damage caused by intense light. Additionally, carotenoids act as precursors for synthesizing abscisic acid (ABA).

Carotenoids belong to the category of phytonutrients and are found within the cells of a broad spectrum of organisms, encompassing bacteria, algae, and plants. Although foods rich in carotenoids are generally recognized by their red, yellow, or orange coloration, exceptions do exist. It is worth highlighting that animals lack the ability to internally synthesize carotenoids and must obtain them through their dietary intake.

Inside the human body, carotenoids function as the predominant source of vitamin A and bestow a myriad of health advantages, including antioxidative effects, immune system modulation, anticancer potential, anti-aging properties, and the prevention of night blindness. The biosynthesis pathway of carotenoids is comprehensively elucidated, commencing with geranylgeranyl diphosphate as the precursor. This intricate pathway is characterized by enzymatic catalysis facilitated by enzymes such as IPI, GGPS, PSY, PDS, ZDS, LycB, and LycE, culminating in the generation of diverse carotenoid compounds.

Categories Of Carotenoids

Carotenoids, with a tally exceeding 750 identified variants, are categorized into two principal groups predicated on their chemical composition. The first category, carotenes, is characterized by their exclusive composition of carbon and hydrogen atoms. In contrast, the second category, xanthophylls, encompasses compounds endowed with oxygen functional groups, including hydroxyl, ketone, carboxyl, and methoxy groups, typified by instances like lutein and astaxanthin. Carotenes exist freely in plants, while xanthophylls can occur in both free and esterified forms in plants due to their capacity to bind with various fatty acids, forming carotenoid esters. Carotenes appear orange, while xanthophylls exhibit a more yellow hue. Notably, lutein and zeaxanthin, prominent xanthophylls, are the sole carotenoids located in the human retina's macula lutea, primarily contributing to ocular health. Their accumulation in the retina may induce ionization and retinal damage. Furthermore, lutein, through its role in inhibiting cholesterol buildup in arteries, plays a role in atherosclerosis prevention. Among the common carotenes are beta-carotene, alpha-carotene, and lycopene. Beta-carotene is associated with sunburn protection and reduced metabolic syndrome risk. Research has suggested that alpha-carotene may have potential longevity benefits, while lycopene is linked to the elimination of free radicals, reduced prostate cancer risk, and the prevention of osteoporosis development.

Our Carotenoids Quantitative Analysis Service

Creative Proteomics has developed two distinct methods for carotenoid detection to meet the diverse needs of our clients: carotenoid detection and saponified carotenoid detection. In contrast to conventional carotenoid detection, saponified carotenoid detection involves the hydrolysis of carotenoid esters to detect the hydrolyzed carotenoids. We have also established a comprehensive result analysis strategy. The complete analysis workflow is illustrated in the diagram below.

We offer two liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods for quantifying various carotenoids in different samples. These methods are characterized by their simplicity, efficiency, broad applicability, and high accuracy. They allow for the rapid detection of three major categories of compounds: carotenoids, xanthophylls, and carotenoid esters, encompassing a total of 66 distinct carotenoids. Our approach employs absolute quantification (with partial isotope internal standards for semi-quantification) to determine carotenoid levels within samples. This aids research scientists in gaining a more precise understanding of carotenoid dynamics within biological systems and exploring their multifaceted functions.

Service Description

Extraction and purification of carotenoids from biological samples.

Quantification of carotenoid content in samples using colorimetric methods.

Determination of individual carotenoid content in samples using HPLC.

Sample Requirements

Fresh and clean plant samples are recommended for sampling, with a sample quantity of >1g.

Prior to sampling, establish control and experimental groups, with a recommendation of 3 or more biological replicates per group.

Samples should be collected swiftly to maintain consistency in timing. Sampling locations should be uniform to ensure consistency in physiological position.

Properly label samples and promptly place them in liquid nitrogen to preserve sample activity.

After sampling, store samples in a -80°C ultra-low-temperature freezer to prevent freeze-thaw cycles.

Technical Advantages

High throughput with multiple carotenoid indices available for selection.

High sensitivity with detection accuracy down to the ng level.

Absolute quantification of standard samples, providing standard curves for each compound.

Instrument identification with additional manual screening, along with pre-sales consultation and post-sales technical support.

Application

Research on plant growth and development.

Studies on plant responses to environmental stress (insect resistance, disease resistance, drought tolerance).

Research on plant nutrition and quality.

Investigation of plant coloration.

Research on plant trait regulation networks.

Carotenoid Chromatograms

Transcriptome analysis and metabolic profilingreveal the key role of carotenoids in thepetal coloration of Liriodendron tulipifera^[2]

The coloration of leaves and petals holds significant economic value in ornamental plants. Liriodendron tulipifera, a highly popular ornamental horticultural plant in North America, features an orange stripe at the base of its leaves. However, the regulatory mechanism responsible for this orange striping remains unclear. This study revealed that during the petal formation process, the petal stripes appear pale yellow when the bracts (modified leaves) have fully senesced or fallen off, while they become deep orange when the petals are fully expanded.

Metabolically, the key pigment responsible for the coloration of petal stripes is the specific local accumulation of γ-carotenoids. At the transcriptional level, there are two major rate-limiting enzymes in the carotenoid synthesis process: carotenoid isomerase (CRTISO) and ε-lycopene cyclase (ε-LCY). These two enzymes are primarily responsible for the accumulation of the specific orange pigments in the petal stripes.

In comparison to Chinese Liriodendron tulipifera, the primary reason for the formation of orange petal stripes in North American Liriodendron tulipifera is the specific expression of ε-LCY.

Gene Regulation in Petal Development

Development of zeaxanthin-rich tomato fruit throughgenetic manipulations of carotenoid biosynthesis^[3]

Carotenoid Metabolic Engineering in Tomatoes for Enhanced Zeaxanthin Content

Zeaxanthin, an oxygen-containing carotenoid, is a lipophilic pigment found in tomatoes and is a dihydroxylated derivative of β-carotene. It is known for its potential health benefits, including the prevention of cardiovascular diseases and the mitigation of atherosclerosis.

In this study, two approaches were employed to increase zeaxanthin content in tomato varieties: transgenic metabolic engineering and conventional breeding methods.

In the conventional breeding approach, hybridization was carried out by crossing a Bsh mutant (lacking the CYCB enzyme responsible for zeaxanthin synthesis) with a high zeaxanthin-producing hp3 individual. The resulting double mutant, BSH/hp3, was then further crossed with a gs individual (containing the STAY-GREEN mutation), yielding a triple mutant. Lastly, this triple mutant was crossed with a high-pigment mutant hp2dg to generate a quadruple homozygous mutant designated as "Xantomato." Throughout these successive crosses, the accumulation of zeaxanthin gradually increased.

In the transgenic approach, the β-carotene hydroxylase (BCH) gene was overexpressed in the BSH/hp3 mutant. This overexpression resulted in the gradual accumulation of zeaxanthin in the fruit during ripening, demonstrating that the overexpression of enzymes upstream in the carotenoid biosynthetic pathway can facilitate the accumulation of zeaxanthin.

These findings reveal that both breeding and transgenic approaches can be effective in enhancing zeaxanthin content in tomatoes.

Composition of Carotenoids (μg/g, FW) in "Xantomato" (a) and Control Group M82 (b): (Note: FW refers to sample fresh weight; DW refers to sample dry weight.)

Improving the cancer prevention/treatment role of carotenoids through various nano-delivery systems^[4]

In recent years, research on the use of natural bioactive compounds and plant-derived chemicals for cancer prevention and treatment has been steadily increasing. Carotenoids, which include substances like lycopene, β-carotene, astaxanthin, and lutein, have garnered attention due to their anti-inflammatory, antioxidant, and free radical scavenging properties. They have also been shown to induce cell cycle arrest, apoptosis, and tumor cell differentiation, contributing to the prevention of various diseases, including cancer and cardiovascular conditions.

However, carotenoids are lipophilic compounds, and their pharmacological functions are often constrained by low solubility and limited bioavailability. The development of novel nanomaterials offers a promising opportunity for targeted delivery and controlled release of carotenoids. This article elaborates on the utilization of various types of nanomaterials to load carotenoids, enabling targeted drug delivery and controlled release. For instance, compared to free β-carotene, β-carotene carried by lipid-based nano-carriers composed of soy lecithin and cholesterol exhibits enhanced apoptosis-inducing effects, serving as a foundation for leukemia treatment. Additionally, the use of poly-L-lysine (PLL)-modified nanoliposomes to deliver lutein helps protect lutein from external conditions and facilitates its release in simulated gastric and intestinal fluids. This approach enhances cellular uptake of lutein, thereby inhibiting the development of human colon cells.

References

1. García-Cerdán JG, Schmid EM, Takeuchi T, et al. Chloroplast Sec14-like 1 (CPSFL1) is essential for normal chloroplast development and affects carotenoid accumulation in Chlamydomonas. Proc Natl Acad Sci U S A. 2020 Jun 2;117(22):12452-12463.
2. Hao Z, Liu S, Hu L, et a. Transcriptome analysis and metabolic profiling reveal the key role of carotenoids in the petal coloration of Liriodendron tulipifera. Hortic Res. 2020 May 1;7:70.
3. Karniel U, Koch A, Zamir D, et al. Development of zeaxanthin-rich tomato fruit through genetic manipulations of carotenoid biosynthesis. Plant Biotechnol J. 2020 Nov;18(11):2292-2303.
4. Zare M, Norouzi Roshan Z, Assadpour E, et al. Improving the cancer prevention/treatment role of carotenoids through various nano-delivery systems. Crit Rev Food Sci Nutr. 2021;61(3):522-534.
5. Seel W, Baust D, Sons D, et al. Carotenoids are used as regulators for membrane fluidity by Staphylococcus xylosus. Sci Rep. 2020 Jan 15;10(1):330.