Introduction and Detection Methods for Phytochemicals

What Are Phytochemicals?

Phytochemicals are natural compounds that have only been discovered so far and are natural food pigments. The human body is unable to produce them and must obtain them from food. Soy isoflavones in soybeans, lycopene in tomatoes, catechins in green tea, carotenoids in carrots, zeaxanthin, polyphenols, etc., are all phytochemicals.

Classification and Functions of Common Phytochemicals

Flavonoids

• Species: Quercetin, brassin, catechin, lignan, anthocyanin, resveratrol
• Functions: Anti-inflammatory, antibacterial, antioxidant, cancer prevention (breast cancer, ovarian cancer), lowering blood lipids and cholesterol

Carotenoids

• Species: Carotene, lutein, zeaxanthin, cryptoxanthin, capsaicin, lycopene
• Functions: Scavenging free radicals, converting into vitamin A to protect cardiovascular system, maintaining vision, inhibiting tumor growth

Phenolic acids

• Species: Chlorogenic acid, ferulic acid, gallic acid, ellagic acid
• Functions: Prevent coronary heart disease, atherosclerosis, cancer (digestive tract cancer, lung cancer, liver cancer), reduce the symptoms of diabetes

Organic Sulfides

• Species: Allicin, glutathione, carotenoid, indole
• Functions: Prevent cancer (breast cancer, prostate cancer), improve liver detoxification, prevent arteriosclerosis

Phytoestrogens

• Species: Lignans, isoflavones, daidzein
• Functions: Bi-directional regulation of estrogen, prevention of osteoporosis, reduction of breast and colon cancer risk

Others

• Species: Malt sterols, chlorophyll, citrulline, citrulline, saponin, bitter glucoside, diosgenin
• Functions: Different effects (hypoglycemia, hypolipidemia, tumor suppression and cancer prevention)

Phytochemicals Analysis

The main challenges of phytochemicals analysis are as follows.

1. Some phytochemicals do not contain highly sensitive detection groups, and coupled with the complexity of the matrix, it is difficult to improve the signal-to-noise ratio. If the sample dosage is limited to the mg or even μg level, their measurable mass is not more than the fg or even ag level, then a highly sensitive method must be used.

1. Some phytochemicals are similar in structure and contain isomers.

1. Some phytochemicals are unstable, easily decomposed or sensitive to the surrounding environment and medium temperature.

1. The living environment of plants is variable. The composition of the organism is complex, and the components are many and variable. The interfering substances contained vary from time to time and from place to place, and are difficult to eliminate. Interference not only changes the detection background and reduces the detection sensitivity, but also affects the separation effect, which in turn affects the qualitative and quantitative accuracy and precision.

All of these issues pose certain challenges for phytochemicals analysis.

Phytochemical Analysis of Extracts from Three Clauseneae Plants (Tanruean et al., 2021)

Creative Proteomics's LC-MS/MS-based platform enables the detection and quantification of phytochemicals. Phytochemicals are enriched and purified by efficient sample pretreatment techniques. Combined with the excellent separation capability of ultra-performance liquid chromatography (UPLC) and the high selectivity of tandem mass spectrometry (MS/MS), the detection of complex sample matrices can effectively reduce the interference of detection, thus improving the sensitivity of phytohormone detection and ensuring the reliability of analytical results.

Reference

Tanruean, K., Poolprasert, P., et al. (2021). Phytochemical analysis and evaluation of antioxidant and biological activities of extracts from three clauseneae plants in Northern Thailand. Plants, 10(1), 117.