Lycium barbarum

Lycium barbarum (goji berries) contains zeaxanthin and polysaccharides that provide antioxidant activity through free radical scavenging mechanisms. The fruit demonstrates DPPH radical scavenging with IC50 values of 830-950 μg/mL and provides significant vitamin C content.

Origin & History

Lycium barbarum, commonly known as goji berry, is a deciduous shrub in the Solanaceae family native to Asia, particularly China, where its bright red fruits are harvested. The bioactive components are extracted mainly via water or methanol methods to isolate polysaccharides (LBP), carotenoids, and phenolic compounds.

Historical & Cultural Context

Lycium barbarum (goji berry) has historical use in Traditional Chinese Medicine, though specific durations, indications, or contexts are not elaborated in the available research. The fruit has been traditionally harvested in China for medicinal purposes.

Health Benefits

• Antioxidant activity: Shows free-radical scavenging properties with IC50 values of 830-950 μg/mL for DPPH• assay (in vitro evidence only)
• Nutritional support: Contains 46% carbohydrates, 13% protein, 16% dietary fiber, and 35 mg vitamin C per 100g fresh fruit (compositional data only)
• Carotenoid source: Rich in zeaxanthin dipalmitate (55.44% of total carotenoids) which may support eye health (no clinical evidence provided)
• Polysaccharide content: Contains unique glycoconjugates (10-2300 kDa) with nine monosaccharides and 22 amino acids (structural characterization only)
• Traditional medicine use: Historical application in Traditional Chinese Medicine (specific indications not detailed in research)

How It Works

Lycium barbarum's antioxidant effects primarily stem from zeaxanthin and polysaccharide compounds that neutralize free radicals through electron donation. The zeaxanthin content specifically targets reactive oxygen species, while polysaccharides enhance cellular antioxidant enzyme systems including superoxide dismutase and catalase. These compounds work synergistically to reduce oxidative stress markers and protect cellular membranes from lipid peroxidation.

Scientific Research

The research dossier lacks specific human clinical trials, RCTs, or meta-analyses for Lycium barbarum. Current evidence is limited to chemical composition studies, nutritional profiles, and in vitro antioxidant activity assessments rather than clinical outcome data.

Clinical Summary

Current evidence for Lycium barbarum is limited primarily to in vitro antioxidant studies showing DPPH radical scavenging activity with IC50 values of 830-950 μg/mL. Compositional analyses confirm significant nutritional content including 35 mg vitamin C per 100g fresh fruit, 46% carbohydrates, and 13% protein. Human clinical trials are sparse, with most research conducted in laboratory settings rather than controlled human studies. The evidence base requires expansion through randomized controlled trials to establish clinical efficacy and optimal dosing protocols.

Nutritional Profile

Lycium barbarum (goji berry) fresh fruit provides approximately 46% carbohydrates, 13% protein (notably high for a fruit), 16% dietary fiber, and 35 mg vitamin C per 100g. The dominant bioactive fraction is polysaccharides (Lycium barbarum polysaccharides, LBPs), typically comprising 20-30% of dry weight, which serve as the primary immunomodulatory and neuroprotective compounds. Carotenoid content is notable, with zeaxanthin dipalmitate representing ~55.44% of total carotenoids; this esterified form shows enhanced stability compared to free zeaxanthin, though intestinal hydrolysis to free zeaxanthin is required for absorption, making bioavailability variable and dependent on dietary fat co-consumption. Betaine content is reported at approximately 0.1% dry weight, contributing to methylation support. Minerals include potassium (~1,132 mg/100g dry), calcium (~112 mg/100g dry), and iron (~9 mg/100g dry). Antioxidant capacity via DPPH• scavenging shows IC50 values of 830–950 μg/mL in vitro; this reflects moderate potency relative to other botanical antioxidants, and in vivo translation remains unconfirmed. Bioavailability of zeaxanthin is meaningfully enhanced when consumed with lipids due to its fat-soluble nature.

Preparation & Dosage

No clinically studied dosage ranges are available from human trials. Studies mention standardization to LBP (Lycium barbarum polysaccharides) but without associated dosing recommendations. Consult a healthcare provider before starting any new supplement.

Synergy & Pairings

Lycium barbarum pairs well with (1) Chrysanthemum morefolium — a classical TCM combination ('Qi Ju Di Huang') where chrysanthemum flavonoids (luteolin, apigenin) provide complementary free-radical scavenging via different mechanistic pathways than LBPs, potentially creating additive antioxidant effects at the ocular level; (2) Astaxanthin — co-administration with this ketocarotenoid may provide additive macular support, as astaxanthin crosses the blood-retinal barrier independently while zeaxanthin dipalmitate (after hydrolysis) selectively deposits in the macula, covering distinct anatomical zones; (3) Omega-3 fatty acids (EPA/DHA from fish oil) — dietary fat substantially increases micellarization and intestinal absorption of zeaxanthin dipalmitate, with studies on carotenoid bioavailability suggesting fat co-ingestion can increase absorption 3–5 fold; (4) Rehmannia glutinosa — another 'Qi Ju Di Huang' constituent whose iridoid glycosides (catalpol) are proposed to complement LBP-mediated neuroprotective signaling via overlapping but non-identical BDNF/PI3K pathway modulation in preclinical models.

Safety & Interactions

Lycium barbarum is generally recognized as safe when consumed as food, with minimal reported adverse effects in healthy individuals. Potential interactions may occur with anticoagulant medications due to compounds that could affect blood clotting mechanisms. Individuals with autoimmune conditions should exercise caution as polysaccharides may stimulate immune system activity. Pregnancy and lactation safety data is insufficient, requiring medical supervision for use during these periods.