Supplements · Femcare actives

Soy Isoflavones & Equol

大豆イソフラボン・エクオール (Daizu isofurabon / Ekuōru)

Also known as: Daidzein, Genistein, Glycitein (aglycone isoflavones), Daidzin, Genistin, Glycitin (glycoside isoflavones), S-Equol, Lactic-acid-fermented Equol

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Trademark notice

Soy isoflavones and equol products are marketed by several Japanese manufacturers under registered trademarks. These trademarks identify a specific company's preparation, brand, or product line and are not interchangeable with the general ingredient names 'soy isoflavones' or 'equol'.

エクエル® / EQUELLE® / ゆらぎ期® — Otsuka's branded lactic-acid-fermented S-Equol supplement (launched 2014) and associated wellness positioning trademarks. EQUELLE® refers specifically to Otsuka's preparation produced by Lactococcus 20-92 fermentation of soy isoflavones; ゆらぎ期® is Otsuka's trademark for the menopausal-transition wellness category. These are not generic terms for equol or for menopausal supplements.
Fuji-Flavone (フジフラボン) — Fujicco's branded soy isoflavone aglycone preparation, supplied for FFC and general supplement formulation. The trademark refers to Fujicco's specific manufacturing process, not to soy isoflavones in general.
AglyMax — Branded soy isoflavone aglycone ingredient, produced via koji-fermentation of soy. The trademark identifies a specific preparation, not an alternative generic name for fermented soy isoflavones.

At a glance

Category	Supplements
Japanese labeling name	ダイズイソフラボン / エクオール
Common Japanese notations	大豆イソフラボン, エクオール, ダイズイソフラボン, S-エクオール
Origin	Plant-derived (Glycine max soybean) and fermented (S-Equol produced by Lactococcus 20-92 from soy isoflavones)
Typical functions	Support for women's wellness through midlife / 'yuragi-ki' (transitional years), Bone-maintenance support (FFC-accepted endpoint), Skin elasticity and quality support, Cardiovascular and metabolic support
Regulatory status in Japan	Soy isoflavone preparations have legacy Tokuho approvals (e.g. for bone support) and several Foods with Function Claims notifications. S-Equol is sold as a dietary supplement ingredient; Otsuka Pharmaceutical's 'Equelle' (2014) was the world's first commercial lactic-acid-fermented S-Equol product.

Soy isoflavones are a family of phytoestrogen compounds (daidzein, genistein, glycitein and their glycosides) found in soybeans and soy-based foods. S-Equol, a downstream metabolite produced from daidzein by gut bacteria, is the bioactive form responsible for many of the observed health endpoints — and only an estimated 50% of Japanese women (versus around 30% of Western women) naturally produce equol from dietary soy. Otsuka Pharmaceutical's 2014 launch of Equelle® was the world's first commercial lactic-acid-fermented S-Equol supplement, allowing consumers without natural equol-producing gut bacteria to obtain the molecule directly.

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Classification

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Product applications

Functions

Regulatory tags

Origin

Common OEM product categories

Finished-product categories where Japanese OEM manufacturers commonly formulate with this ingredient.

Femcare and 'yuragi-ki' supplements
Bone-support FFC supplements
Beauty drinks and jelly formats
Tokuho-approved soy isoflavone food products (legacy)

Ingredient profile

Soy isoflavones occur in soybeans (Glycine max) primarily as glycosides (daidzin, genistin, glycitin), which are converted to their bioactive aglycone forms (daidzein, genistein, glycitein) by intestinal beta-glucosidases or by fermentation. Aglycone-form ingredients (such as koji-fermented soy isoflavones) are commonly used in Japanese supplements because they are absorbed more rapidly and consistently than the glycoside forms.

S-Equol is a chiral isoflavone metabolite derived from daidzein via reduction by specific gut bacteria. In the human population, only a subset of individuals carries equol-producing gut microbiota; estimates indicate around 50% of Japanese versus around 30% of Western women are natural equol producers. To address this gap, Otsuka Pharmaceutical isolated 'Lactococcus 20-92', a lactic-acid bacterium capable of producing S-Equol from soy daidzein, and commercialised the resulting fermented S-Equol in the Equelle® product (2014).

Commercial supplement preparations include standardised soy isoflavone aglycone powders (e.g. Fuji-Flavone, AglyMax) and fermented S-Equol concentrates (Equelle®). Cosmetic preparations of soy isoflavone extract are also used, but the entry's primary positioning is as a supplement / functional food active.

OEM applications

In Japan, soy isoflavone and equol products are most strongly associated with the 'yuragi-ki' (ゆらぎ期 — the menopausal transition years) wellness category. Tablet, soft-gel, and jelly supplements are positioned around midlife wellness, hormonal balance support, and skin quality. Daily dosing is set per FFC notification or general supplement design and should respect the Japanese Food Safety Commission's recommended upper limit on aglycone-form isoflavone intake.

Bone-maintenance positioning is supported by legacy Tokuho approvals and current Foods with Function Claims notifications. Soy isoflavones are also used in beauty drinks, fortified bars, and women's wellness functional foods, often paired with calcium, vitamin D, collagen peptide, or placenta extract depending on the wellness narrative.

Regulatory classification in Japan

Soy isoflavone preparations have legacy Tokuho (特定保健用食品) approvals — notably for bone-support positioning — granted by the Consumer Affairs Agency. Several Foods with Function Claims (機能性表示食品) notifications using soy isoflavones for bone maintenance and related endpoints have also been accepted; brands wishing to make similar claims must submit their own FFC notification with appropriate supporting evidence.

The Food Safety Commission of Japan has issued guidance on a recommended upper daily intake for isoflavone aglycones from supplement use (separate from intake via traditional soy foods). Brands formulating soy isoflavone supplements for the Japanese market should design daily dosing in line with this guidance.

S-Equol as a fermented dietary supplement ingredient is sold in Japan under DSHEA-equivalent dietary supplement framing; Otsuka's Equelle® is the reference commercial product. Brands considering similar fermented S-Equol positioning should review the regulatory and IP landscape carefully — including Otsuka's Lactococcus 20-92 portfolio.

Regulatory classification in other markets

EU	Isolated soy isoflavone preparations are subject to the Novel Food framework and to EFSA opinions on safety; specific health claims are tightly regulated under the EU health claims register. S-Equol supplement positioning should be reviewed against current EFSA guidance before launch.
USA	Soy isoflavone and S-Equol products are sold as dietary supplements under DSHEA. FDA-notified structure / function claims are available; specific health claims (e.g. heart health) are tightly regulated and require an authorised claim or qualified-claim review.
China	Soy isoflavone health food products are subject to NMPA / SAMR health-food review; specific functions must align with the approved health-food claims list. Verify supplier documentation and any required NMPA filings before launch.
Korea	Soy isoflavone is recognised by the MFDS as a health-functional food ingredient under specific approved claims (e.g. bone health for postmenopausal women). S-Equol products require their own MFDS health-functional-food review.

Market reference formulations

Example finished products will be added after each product's current full ingredient list and (for FFC / Tokuho versions) Consumer Affairs Agency notification or approval has been verified. Because the category is heavily trademarked — particularly around Otsuka's Equelle® and ゆらぎ期® brand portfolio — any example entries will carefully distinguish the general ingredient (soy isoflavones / S-Equol) from trademarked product names.

All brand names and product names referenced anywhere on this site are the property of their respective owners. Example entries are provided for informational purposes only and do not imply endorsement.

Typical OEM use levels

Formulation ranges per finished-product application. Verify against the cited source before production.

Application	Typical range	Regulatory limit	Notes
Functional Food (FFC) — menopause / bone-health claim (Japan)	Daily intake 10 mg S-equol per FFC notifications (representative)	Per consumer-affairs notification; published in 機能性表示食品DB	Differs from native soy isoflavones — equol is the gut-microbiome metabolite, supplied as direct fermentation product(消費者庁機能性表示食品データベース / 食品安全委員会大豆イソフラボン安全性評価)

Storage requirements

How the receiving OEM facility needs to handle inbound raw material.

Temperature: Refrigerated 4°C for fermentation product; spray-dried at room temp
Conditions: Sealed against moisture; protect from light
Shelf life: 24 months sealed

Supply concentration

Where this ingredient comes from — useful for single-source-risk planning.

Primary regions: Otsuka Pharmaceutical (Tokushima) is the principal Japanese producer of S-equol via direct fermentation
Import dependence: Equol supply mostly domestic; native soy isoflavones globally produced

Otsuka Pharmaceutical EQUELLE references

Certifications commonly available

Certification schemes commonly obtainable for this raw material. Always confirm the specific supplier's current certificate before contracting.

Scheme	Availability
GMP (food / supplement)	Standard
Halal	On-request
Kosher	On-request
Vegan	Common
Non-GMO	Common	Soy substrate sourcing matters
FFC notification ready	Standard

Alternative ingredients

Related ingredients commonly evaluated as substitutes.

Quick answers

What is Soy Isoflavones & Equol?: Soy isoflavones are a family of phytoestrogen compounds (daidzein, genistein, glycitein and their glycosides) found in soybeans and soy-based foods. S-Equol, a downstream metabolite produced from daidzein by gut bacteria, is the bioactive form responsible for many of the observed health endpoints — and only an estimated 50% of Japanese women (versus around 30% of Western women) naturally produce equol from dietary soy. Otsuka Pharmaceutical's 2014 launch of Equelle® was the world's first commercial lactic-acid-fermented S-Equol supplement, allowing consumers without natural equol-producing gut bacteria to obtain the molecule directly.
What is the regulatory status of Soy Isoflavones & Equol in Japan?: Soy isoflavone preparations have legacy Tokuho approvals (e.g. for bone support) and several Foods with Function Claims notifications. S-Equol is sold as a dietary supplement ingredient; Otsuka Pharmaceutical's 'Equelle' (2014) was the world's first commercial lactic-acid-fermented S-Equol product.
What products typically use Soy Isoflavones & Equol?: Femcare and 'yuragi-ki' supplements / Bone-support FFC supplements / Beauty drinks and jelly formats / Tokuho-approved soy isoflavone food products (legacy)
Where does Soy Isoflavones & Equol come from?: Plant-derived (Glycine max soybean) and fermented (S-Equol produced by Lactococcus 20-92 from soy isoflavones)
What is the INCI / JSCI labeling name for Soy Isoflavones & Equol?: JSCI: ダイズイソフラボン / エクオール

Often used with

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Same category

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Used in similar product applications

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Sharing similar functions

Ingredients that overlap on functional benefit tags.

From the same origin

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FAQ for OEM buyers

Q. Why is the difference between aglycone and glycoside isoflavones important when choosing a soy isoflavone ingredient?

Soy isoflavones occur in soybeans primarily as glycosides (daidzin, genistin, glycitin), which the body cannot absorb intact — gut β-glucosidases must first hydrolyse the sugar moiety to release the aglycone forms (daidzein, genistein, glycitein) before absorption. As a result, aglycone-rich preparations (often produced by koji or microbial fermentation of soy) are absorbed faster than equivalent glycosides — published pharmacokinetic studies report time-to-peak (Tmax) for the aglycones around 5–7 hours versus around 9 hours for the glycosides. The two forms are not interchangeable for label-dose calculations: a milligram value for 'soy isoflavones' may refer to glycoside weight or to the aglycone-equivalent weight, and the distinction matters for both efficacy and Japan's safety-intake guidance.