Home Ingredients AstaFerm® (Fermented Astaxanthin)

AstaFerm® (Fermented Astaxanthin)

Phaffia rhodozyma
Evidence Level
Preliminary
4 Clinical Trials
6 Documented Benefits
1/5 Evidence Score

AstaFerm® is astaxanthin, a red carotenoid, made by fermenting the yeast Phaffia rhodozyma (also called Xanthophyllomyces dendrorhous) rather than by growing Haematococcus algae. It was developed by NextFerm Technologies in Israel, which describes it as a free, non-esterified astaxanthin with a different structure from algae astaxanthin. Lab analyses show Phaffia yeast makes mainly the 3R,3'R mirror-image form, while algae astaxanthin contains the 3S,3'S form, so trials of algae products cannot simply be credited to it. No published human trial of AstaFerm was found. The maker registered a single-dose absorption study in 12 healthy men, but no results have been posted. Rat studies of other Phaffia materials found no toxic effects. NextFerm reported a self-affirmed GRAS conclusion, which FDA has not reviewed, and in 2025 the company suspended most of its operations, so current supply of AstaFerm is uncertain.

Studied Dose No dose of AstaFerm has published results. The maker's registered study gave one 50 mg dose to 12 healthy men, with no results posted. EFSA judged up to 8 mg a day of astaxanthin from supplements safe for adults.
Active Compound Astaxanthin from fermentation of the yeast Phaffia rhodozyma (Xanthophyllomyces dendrorhous), described by the maker as free, non-esterified astaxanthin. Phaffia yeast makes mainly the 3R,3'R form. The maker lists 5% and 10% oils for softgels, a 30% powder for gummies and a 5% cold-water dispersible powder.

Benefits

Astaxanthin made by yeast fermentation instead of algae

AstaFerm is astaxanthin produced by the yeast Phaffia rhodozyma, which the maker says it grows in closed fermentation tanks. The maker describes it as free, non-esterified astaxanthin that is neutral in taste and odor, supplied as oils for softgels and powders for gummies and drinks. No published human trial has tested it for any health outcome.

Supported by Trial 1, Trial 2

Absorption of a single 50 mg dose: registered, results not posted

The maker registered an open-label study in which 12 healthy men took one 50 mg dose of AstaFerm with breakfast, with blood levels tracked for 7 days and side effects recorded. The registry lists it as completed, but no results have been posted and no published paper was found, so its absorption and tolerance are not known.

Supported by Trial 1, Trial 2

Mirror-image form compared with algae astaxanthin

Phaffia yeast makes mainly 3R,3'R astaxanthin, while algae astaxanthin contains the 3S,3'S form. Human data on how each form is absorbed disagree: in 3 men given a blend of forms, 3R,3'R rose more in blood than its share of the dose, while in men eating salmon for 4 weeks the 3R,3'R share in blood ended slightly lower than in the fish.

Supported by Trial 4, Trial 3

Antioxidant enzyme and safety findings in rats

In rats, a Phaffia astaxanthin extract from another maker showed no toxic effects at up to 1,000 mg/kg a day for 4 weeks, and it did not damage genes in bacterial and mouse tests. In a 90-day rat study, whole Phaffia yeast powder showed no regular toxic effects and raised the antioxidant enzyme glutathione peroxidase. Neither study tested AstaFerm or people.

Supported by Trial 2, Trial 1

Blood fats in a registered trial of another Phaffia product

A separate company registered a 12-week placebo-controlled trial of a Phaffia astaxanthin supplement (6 mg capsules, two a day) in 68 adults with raised blood triglycerides. It is listed as completed, but no results have been posted and it did not use AstaFerm, so it adds no evidence on outcomes.

Supported by Trial 2, Trial 1

Evidence from algae astaxanthin applies to a different material

Many human astaxanthin trials, summarized on the Astaxanthin page, used Haematococcus algae astaxanthin, which contains the 3S,3'S form as esters, where the clearest results are for skin moisture and elasticity. Those results come from another source, form and stereoisomer and have not been shown for AstaFerm.

Supported by Trial 3, Trial 2

Mechanism of action

1

Same molecule, different mirror-image form

Astaxanthin has two chiral centers. In lab analyses, Phaffia yeast produced astaxanthin mainly in the 3R,3'R configuration, and a recent chiral test found no 3S,3'S astaxanthin in Phaffia yeast powder while detecting it in Haematococcus algae powder. Whether this difference changes effects in people has not been tested.

2

Free astaxanthin versus esters

NextFerm describes AstaFerm as free, non-esterified astaxanthin and says this boosts uptake, while algae extracts carry astaxanthin as fatty acid esters. In a small human study, esters were not found in blood after a meal, meaning they are split during absorption; no study has compared free and esterified forms for AstaFerm.

3

Gut transporter preference (lab and animal work)

In cell experiments and an animal intestine model, the uptake protein CD36 took up 3S,3'S astaxanthin more readily than 3R,3'R, and blocking CD36 cut absorption of the 3S,3'S form more. These lab findings suggest the two forms may be absorbed differently, but they have not been confirmed in people.

Clinical trials

1
AstaFerm Single-Dose Safety and Absorption Study (Registered, No Results Posted)
PubMed

Single-center, open-label, non-randomized, single-dose study registered as NCT03807050; one 50 mg dose of astaxanthin from Phaffia rhodozyma in capsules after a fat-balanced breakfast, with blood sampling up to 168 hours; sponsored by the maker (NextFerm Technologies LTD 2019, ClinicalTrials.gov)

12 healthy non-smoking men aged 18 to 45.

The registry lists the study as completed in February 2019, with peak blood level, exposure over time and adverse events as outcomes. No results have been posted on the registry and no published paper was found, so nothing is known about how well AstaFerm was absorbed or tolerated.

2
Phaffia Astaxanthin and Blood Triglycerides: Registered Trial of Another Product (No Results Posted)
PubMed

Randomized, quadruple-blind, placebo-controlled, parallel trial registered as NCT02343497; astaxanthin from Phaffia rhodozyma, 6 mg capsules, two a day for 12 weeks; primary outcome fasting plasma triglycerides; not AstaFerm (Ajinomoto Foods Europe SAS 2018, ClinicalTrials.gov)

68 adults aged 18 to 60 with fasting triglycerides of 1.2 to under 4 g/L.

The registry lists the trial as completed in November 2015. No results have been posted and no published paper was found, so it provides no evidence on blood fats or safety for Phaffia astaxanthin.

3
Blood Uptake of Astaxanthin Mirror-Image Forms After a Single Dose
PubMed

Small human pharmacokinetic study; single meals with 10 mg and, 4 weeks later, 100 mg of astaxanthin as fatty acid diesters, made up of 3R,3'R, meso and 3S,3'S forms in a 31:49:20 ratio; plasma followed for 76 hours; not AstaFerm (Coral-Hinostroza et al. 2004, Comp Biochem Physiol C Toxicol Pharmacol)

3 healthy middle-aged men aged 41 to 50.

The 3R,3'R form made up 54% of astaxanthin in blood but only 31% of the dose, so it accumulated selectively. No esters were found in plasma. Peak blood level after 100 mg was 0.28 mg/L at about 11.5 hours, and the response to dose was not linear. With only 3 people, this is a pharmacokinetic signal, not proof of a benefit.

4
Astaxanthin Mirror-Image Forms From Wild and Farmed Salmon in Healthy Men
PubMed

Randomized, double-blind study; 250 g of wild or farmed salmon daily for 4 weeks, providing 5 micrograms of astaxanthin per gram of fish; plasma astaxanthin and its isomers measured by chiral HPLC; not AstaFerm (Rüfer et al. 2008, Br J Nutr)

28 healthy men.

Plasma astaxanthin plateaued after 6 days (39 nmol/L with wild and 52 nmol/L with farmed salmon), and the isomer pattern in blood resembled the fish eaten. After 28 days, the 3S,3'S share in blood was slightly higher and the 3R,3'R share slightly lower than in the fish, which the authors suggest reflects selective absorption.

Side effects and drug interactions

Common Potential side effects

No safety data on AstaFerm in people have been published. The maker's single-dose study listed adverse events as an outcome, but no results have been posted.
In rats, a Phaffia astaxanthin extract from another maker caused no toxic effects at up to 1,000 mg/kg a day for 4 weeks, and whole Phaffia yeast powder at up to 20% of the diet for 90 days showed no regular toxic effects.
EFSA judged 8 mg of astaxanthin a day from supplements, on top of the usual diet, safe for adults, but noted that children and adolescents could reach or exceed its acceptable daily intake.
Pregnancy, breastfeeding and long-term use have not been studied for this material.

Important Drug interactions

No drug interaction studies of AstaFerm or Phaffia astaxanthin were found.
The Astaxanthin page describes interaction signals for astaxanthin in general, including blood thinners; ask a doctor or pharmacist before use if you take regular medicines.

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Frequently asked questions about AstaFerm® (Fermented Astaxanthin)

What is AstaFerm?

AstaFerm is an astaxanthin ingredient made by fermenting Phaffia rhodozyma yeast, developed by NextFerm Technologies in Israel. The maker describes it as free, non-esterified astaxanthin with neutral taste and odor, sold as oils for softgels and as powders for gummies and drinks.

Has AstaFerm been tested in people?

No published human trial of AstaFerm was found. The maker registered a single-dose absorption and safety study in 12 healthy men that was completed in 2019, but no results have been posted.

How is yeast astaxanthin different from algae astaxanthin?

Both contain the same astaxanthin molecule, but Phaffia yeast makes mainly the 3R,3'R mirror-image form (which the maker says it supplies in free, non-esterified form), while Haematococcus algae extracts contain the 3S,3'S form as esters. Many human astaxanthin trials used algae material, and how far their results carry over to yeast astaxanthin has not been tested.

How much AstaFerm should I take?

No dose of AstaFerm has been tested for any benefit. EFSA considers up to 8 mg of astaxanthin a day from supplements safe for adults, but not necessarily for children and teens. Follow the product label and ask a doctor if you are pregnant, breastfeeding or take regular medicines.

Is AstaFerm regulated or approved by FDA?

FDA does not approve supplements. NextFerm reported a self-affirmed GRAS conclusion for AstaFerm, which FDA has not reviewed, and FDA's GRAS notice inventory and new dietary ingredient list show no filing from NextFerm. In 2025 the company suspended most of its operations, so current supply of AstaFerm is uncertain.

What is AstaFerm used for?

NutraSmarts does not list AstaFerm under a health category. What the research covers: AstaFerm is astaxanthin produced by the yeast Phaffia rhodozyma, which the maker says it grows in closed fermentation tanks.

Is AstaFerm safe, and does it have side effects?

Side effects and cautions reported for AstaFerm include: No safety data on AstaFerm in people have been published. The maker's single-dose study listed adverse events as an outcome, but no results have been posted. It may also interact with some medications. AstaFerm is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does AstaFerm interact with any medications?

Possible interactions include: No drug interaction studies of AstaFerm or Phaffia astaxanthin were found. The Astaxanthin page describes interaction signals for astaxanthin in general, including blood thinners; ask a doctor or pharmacist before use if you take regular medicines. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for AstaFerm?

NutraSmarts rates the evidence for AstaFerm as Preliminary (1 out of 5). It is backed by 4 study summaries and 16 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(16 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. NextFerm Technologies LTD. Safety and Pharmacokinetics of Astaxanthin-Rich Carotenoid Extract (AstaFerm™) Administered as a Single Oral Dose to Healthy Adults (NCT03807050) ClinicalTrials.gov (trial registry). 2019;Registry record NCT03807050, first posted 2019-01-16, last updated 2019-03-21; accessed 2026..SourceUsed to support: Trial registry record, not PubMed-indexed, read in 2026. Sponsored by NextFerm: a single-center, open-label, non-randomized study in which 12 healthy men aged 18 to 45 took one 50 mg dose of astaxanthin from Phaffia rhodozyma (AstaFerm) with breakfast, with blood sampled up to 168 hours. Outcomes were Cmax, AUC and adverse events. Listed as completed (February 2019) with no results posted.
  2. Ajinomoto Foods Europe SAS. Randomized, Double-blind, Placebo-controlled, Parallel-group Design, Monocentric Study on Lipid-lowering Effects of an Astaxanthin Supplement in Volunteers With Mild Dyslipidemia (NCT02343497) ClinicalTrials.gov (trial registry). 2018;Registry record NCT02343497, first posted 2015-01-22, last updated 2018-01-09; accessed 2026..SourceUsed to support: Trial registry record, not PubMed-indexed, read in 2026. A 12-week randomized, quadruple-blind, placebo-controlled trial of an astaxanthin supplement from Phaffia rhodozyma (6 mg capsules, two a day) in 68 adults with fasting triglycerides of 1.2 to under 4 g/L; primary outcome fasting triglycerides. Listed as completed (November 2015) with no results posted. It did not use AstaFerm.
  3. Grewe C, Menge S, Griehl C. Enantioselective separation of all-E-astaxanthin and its determination in microbial sources. J Chromatogr A. 2007;1166(1-2):97-100. doi: 10.1016/j.chroma.2007.08.002.PubMedUsed to support: Laboratory chiral HPLC method study: the yeast Xanthophyllomyces (Phaffia) produced astaxanthin predominantly in the R,R configuration, whereas the green microalga Scenedesmus made mainly the S,S form. Analytical chemistry, not a health study.
  4. Liu L, Cheng P, Xiao Y, Chen S, Zhang Y, Chen W, Fu F, Lin Z, Dong Y. Direct chiral-selective detection of (3S,3'S)-astaxanthin using hydrogel-based SERS chips. Food Chem. 2026;525(Pt 3):150583. doi: 10.1016/j.foodchem.2026.150583.PubMedUsed to support: Analytical method study: a chiral-selective sensor detected (3S,3'S)-astaxanthin in Haematococcus pluvialis powders, consistent with HPLC, and found no (3S,3'S)-astaxanthin in Phaffia rhodozyma yeast powders. Laboratory analysis only.
  5. Coral-Hinostroza GN, Ytrestøyl T, Ruyter B, Bjerkeng B. Plasma appearance of unesterified astaxanthin geometrical E/Z and optical R/S isomers in men given single doses of a mixture of optical 3 and 3'R/S isomers of astaxanthin fatty acyl diesters. Comp Biochem Physiol C Toxicol Pharmacol. 2004;139(1-3):99-110. doi: 10.1016/j.cca.2004.09.011.PubMedUsed to support: Human pharmacokinetic study in 3 men aged 41 to 50 given single meals with 10 mg and later 100 mg astaxanthin as diesters (3R,3'R : meso : 3S,3'S = 31:49:20). Esters were not detected in plasma; Cmax after 100 mg was 0.28 mg/L at 11.5 hours, half-life 52 hours, and the dose response was non-linear. The 3R,3'R isomer accumulated selectively, making up 54% of plasma astaxanthin versus 31% of the dose. Not AstaFerm.
  6. Rüfer CE, Moeseneder J, Briviba K, Rechkemmer G, Bub A. Bioavailability of astaxanthin stereoisomers from wild (Oncorhynchus spp.) and aquacultured (Salmo salar) salmon in healthy men: a randomised, double-blind study. Br J Nutr. 2008;99(5):1048-54. doi: 10.1017/S0007114507845521.PubMedUsed to support: Randomized, double-blind study in 28 healthy men eating 250 g of wild or farmed salmon daily for 4 weeks (5 micrograms astaxanthin per gram). Plasma astaxanthin plateaued after 6 days at 39 nmol/L (wild) and 52 nmol/L (farmed); the plasma isomer pattern resembled the fish, with the 3S,3'S share slightly higher and the 3R,3'R share slightly lower than in the fish after 28 days. Not AstaFerm.
  7. Lao Y, Zhang J, Wang T, Xiao J, Cao Y, Xiao H, Liu X. Intestinal Absorption of Dietary Astaxanthin Mediated by Cluster-Determinant 36 (CD36) Presents Stereoisomeric Selectivity In Vitro and In Vivo. J Agric Food Chem. 2026;74(5):4407-4419. doi: 10.1021/acs.jafc.5c11047.PubMedUsed to support: Docking, cell and in situ animal intestine study (species not stated in the abstract): the transporter CD36 bound (3S,3'S)-astaxanthin more strongly, CD36-overexpressing cells took up 14.44% more of the S form than the R form, and a CD36 inhibitor cut duodenal and jejunal absorption of the S form by about 84% versus 49% and 36% for the R form. Laboratory and animal data only.
  8. Tago Y, Fujii T, Wada J, Kato M, Wei M, Wanibuchi H, Kitano M. Genotoxicity and subacute toxicity studies of a new astaxanthin-containing Phaffia rhodozyma extract. J Toxicol Sci. 2014;39(3):373-82. doi: 10.2131/jts.39.373.PubMedUsed to support: Toxicology study of a Phaffia rhodozyma astaxanthin extract whose first author is from Kaneka Corporation, not AstaFerm: no mutations in a bacterial reverse mutation test, no chromosome damage in a mouse micronucleus test at 2,000 mg/kg, and no distinct toxicity in rats given 500 or 1,000 mg/kg by gavage for 4 weeks (no-observed-adverse-effect level above 1,000 mg/kg extract, equal to 50 mg/kg astaxanthin). Animal and laboratory data only.
  9. Wang Y, Piao Y, Chen N, Zhang Y, Zhang X, Wang C, Zhao C, Yu M, Zhang T. Xanthophyllomyces dendrorhous Is a Safe Dietary Supplement with Potent Antioxidant Defense Enhancing Activity. J Agric Food Chem. 2024;72(34):19167-19176. doi: 10.1021/acs.jafc.4c04062.PubMedUsed to support: Rat study of whole Xanthophyllomyces dendrorhous (Phaffia) yeast powder, not AstaFerm: the oral LD50 was above 12 g/kg, and over 90 days at 2.5% to 20% of the diet there were no regular toxic effects, though triglycerides rose in males at 10% and 20% (attributed to higher dietary fat) and white blood cells rose at 20%. Glutathione peroxidase activity rose 16% to 36% in males. One author lists affiliations with an astaxanthin company. Animal data only.
  10. EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA), Turck D, Castenmiller J, de Henauw S, Hirsch-Ernst KI, Kearney J, Maciuk A, Mangelsdorf I, McArdle HJ, Naska A, Pelaez C, Pentieva K, Siani A, Thies F, Tsabouri S, Vinceti M, Cubadda F, Engel KH, Frenzel T, Heinonen M, Marchelli R, Neuhäuser-Berthold M, Poulsen M, Sanz Y, Schlatter JR, van Loveren H, Ackerl R, Gelbmann W, Steinkellner H, Knutsen HK. Safety of astaxanthin for its use as a novel food in food supplements. EFSA J. 2020;18(2):e05993. doi: 10.2903/j.efsa.2020.5993.PubMedUsed to support: EFSA opinion: using an acceptable daily intake of 0.2 mg/kg body weight, combined intake of astaxanthin from the background diet plus 8 mg a day from food supplements is safe for adults, while adolescents aged 14 to under 18 reach the ADI and younger children and infants exceed it. The earlier 2014 assessment it updates concerned astaxanthin from Haematococcus pluvialis.
  11. NextFerm Technologies USA Inc. AstaFerm® product page NextFerm (manufacturer website). 2026;Manufacturer web page, accessed 2026-11-13..SourceUsed to support: Manufacturer web page, not PubMed-indexed, read in 2026. It calls AstaFerm the first and only fermented astaxanthin and claims fast and effective absorption, without citing data, and lists 5% and 10% oils for softgels, a 30% powder for gummies and a 5% cold-water dispersible powder. It names no stereoisomer and cites no human study. FDA's new dietary ingredient list shows an earlier Phaffia astaxanthin from another company (Igene Biotechnology, Aquasta, notified 2013), so the first-and-only claim is the maker's own. A product description, not health evidence.
  12. Schultz H. Israeli startup debuts astaxanthin from yeast for human consumption NutraIngredients. 2018;Trade press article, 14 November 2018; accessed 2026..SourceUsed to support: Trade press article, not PubMed-indexed, read in 2026. Reports NextFerm's launch of AstaFerm from Phaffia rhodozyma yeast grown by closed-tank fermentation, produced in a free, non-esterified form that the company says boosts uptake, and described as a different stereoisomer from Haematococcus algae astaxanthin; it was offered as 10% beadlets. The claims are the company's own.
  13. Marrapodi A. NextFerm announced self-GRAS status of its fermented astaxanthin oil for soft-gels Nutritional Outlook. 2021;Trade press article, 7 September 2021; accessed 2026..SourceUsed to support: Trade press article, not PubMed-indexed, read in 2026. Reports that NextFerm Technologies announced a self-affirmed GRAS conclusion for AstaFerm oil for softgels and that AstaFerm was sold in the US and Canada in gummies and powders. A self-affirmed GRAS conclusion is the company's own determination and is not an FDA review.
  14. Weinreb G. Food-tech co NextFerm suspends operations Globes. 2025;News article, 2 April 2025; accessed 2026..SourceUsed to support: News article, not PubMed-indexed, read in 2026. Reports that NextFerm suspended operations except for a yeast joint venture in India, informed its 11 employees, and was seeking a buyer for its activity. It does not mention AstaFerm specifically, so current supply is uncertain.
  15. US Food and Drug Administration. List of New Dietary Ingredient Notifications, 1995 to the present FDA (government database). 2026;Downloadable NDIN list (XLSX), accessed 2026-11-13..SourceUsed to support: Government list, not PubMed-indexed, read in 2026. It contains no notification from NextFerm. Phaffia entries are from another company, Igene Biotechnology: NDIN 83 (Phaffia rhodozyma, submitted 2000) and NDIN 814 (astaxanthin-rich Phaffia rhodozyma, Aquasta, submitted 2013). Most other astaxanthin entries are Haematococcus pluvialis extracts described as containing astaxanthin esters.
  16. US Food and Drug Administration. GRAS Notices inventory (searches for astaxanthin, Phaffia, Xanthophyllomyces and NextFerm) FDA (government database). 2026;Online GRAS Notice Inventory, searched 2026-11-13..SourceUsed to support: Government database, not PubMed-indexed, searched in 2026. Searches for Phaffia, Xanthophyllomyces and NextFerm returned 0 records. A search for astaxanthin returned GRN 294, 356 and 580 (Haematococcus pluvialis extracts containing astaxanthin esters) and GRN 700 (Paracoccus carotinifaciens extract); none covers yeast astaxanthin or AstaFerm.