iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
Broccoli compounds can inhibit the growth of some bacteria in laboratory tests, but that does not mean eating broccoli treats an infection. The clearest findings concern sulforaphane and particular broccoli extracts tested against specific organisms under specific conditions.
What in broccoli may inhibit bacterial growth?
The main compound discussed in these studies is sulforaphane, an isothiocyanate associated with broccoli and other cruciferous vegetables. Broccoli contains glucoraphanin, which can be converted into sulforaphane through the activity of the enzyme myrosinase. Studies have tested both sulforaphane itself and extracts made from broccoli or broccoli sprouts; those are not interchangeable preparations.
A 2025 review summarized 28 reports on sulforaphane’s antibacterial effects, including studies of different bacterial groups, virulence factors, immune responses and human research. The review describes an active research area, not a proven broccoli-based treatment for infection. Read the 2025 review on PubMed.
What did laboratory studies find?
Sulforaphane affected many—but not all—organisms in one test panel
A 2008 in vitro study tested sulforaphane against 28 microbial species. It reported growth inhibition in 23, with minimum inhibitory concentrations of 1–4 μg/mL for those inhibited species. The study described Pseudomonas aeruginosa, three methicillin-resistant Staphylococcus aureus (MRSA) isolates, and Candida albicans as resistant in the tests. Because this was a defined laboratory panel, its result should not be read as evidence that sulforaphane works against bacteria generally or in a person’s body. See the 2008 study on PubMed.
#1 Best Overall
- Brassica Oleracea Var. Italica: These finest quality, non-GMO, USDA Organic Waltham 29 Broccoli seeds produce crisp, crunchy, dark greenish-blue florets, leaves and stems that are packed with flavor and vitamins. They’re great on a plate!
- For Best Results: Harvest broccoli in the morning, when the buds of the head are firm and tight, just before the heads flower. Store in a refrigerator up to 5 days; or blanch and freeze for up to a year.
- Freshly Packed: These seeds are packed for the current growing season and will provide high germination rates next year as well.
- Certified Organic: All Purely Organic Seeds are open pollinated, non-GMO (not genetically modified), heirloom, organic seeds. Each Purely Organic Seed Packet carries the USDA Organic Seal signifying that is has passed rigorous standards and been certified organic by a USDA Accredited agency.
- Premium Packaging: All seeds from Purely Organic Products are packaged in individually styled packets ideal for gifts, storage or immediate use. Each packet displays the plant variety on the front with instructions and plant facts on the back.
Broccoli extracts and cooking method produced different results
A 2020 study tested extracts from raw broccoli, cooked broccoli, and cooked broccoli with mustard seeds. In its laboratory tests, raw broccoli extract showed antimicrobial activity only against Bacillus cereus; cooked extracts showed activity against several tested pathogens. This is a result about those extracts and test conditions, not a recommendation to cook broccoli in a particular way for food safety or infection prevention. Read the 2020 study in PubMed Central.
Studies also tested broccoli sprouts against H. pylori
Two studies focused on Helicobacter pylori, a bacterium associated with stomach disease. A 2002 study reported that sulforaphane inhibited reference strains and clinical isolates, including antibiotic-resistant isolates, in laboratory tests. A 2010 study examined broccoli sprout extracts and related compounds and reported anti-H. pylori activity for several extracts and synthesized compounds. These findings concern specified compounds and laboratory outcomes; they do not show that eating broccoli or sprouts can replace diagnosis or medical treatment. Read the 2010 study on PubMed; read the 2002 study in PubMed Central.
Rank #2
- GROW NUTRITIOUS BROCCOLI SPROUTS AT HOME: Enjoy vitamin-packed organic broccoli sprouts with Nature Jims' broccoli sprout seeds. Ideal for indoor and outdoor growing, these seeds for sprouting offer fresh, healthy sprouts in no time.
- CERTIFIED ORGANIC BROCCOLI SEEDS FOR SPROUTING: Our non-GMO, organic broccoli seeds are renowned for quality, ensuring you receive premium seeds for sprouting. Perfect for growing nutrient-rich broccoli sprouts right at home.
- SWIFT-GROWING MICROGREEN SEEDS: Nature Jims' broccoli seeds for sprouting sprout in just 5 days! Enjoy fresh, crunchy sprouts in no time, ideal for those who want healthy microgreens that grow quickly.
- HEALTH BENEFITS OF BROCCOLI SPROUTS: Packed with sulforaphane, our organic broccoli sprout seeds elevate your defense system and promote healthy digestion for overall wellness. Enjoy the power of nature with every sprout!
- ESTABLISHED QUALITY SINCE 1955: With nearly 60 years of experience, Nature Jims has been providing premium organic sprouting seeds and microgreens. With unwavering confidence in our product, we ensure the quality of our seeds.
Does eating broccoli inhibit bacteria in the human gut?
The human component of the 2020 study involved 11 people with ileostomies who consumed broccoli soup. It examined the delivery of broccoli phytochemicals through the digestive tract, not whether participants’ infections improved. The study reported that less than 1% of sulforaphane was recovered in ileal fluids. Adding mustard seed powder increased the amount of sulforaphane available to the colon sixfold, but material from the ileal sample with the highest sulforaphane level did not inhibit E. coli K12 in the reported assay.
Free tools Windows power users keep installed
One-click scans. No signup required.
The authors concluded that sulforaphane-rich broccoli extracts had antimicrobial effects in vitro and that consuming enriched broccoli soup may inhibit bacterial growth in the stomach and upper small intestine, but not in the terminal ileum or colon. The small study and its delivery-focused measures do not establish an effect on active infections or a clinical benefit from eating broccoli.
Rank #3
- Beautiful - Large premium packet of Waltham 29 Broccoli (Brassica oleracea) seeds. A reliable heirloom that produces 5-6" blue-green heads and an abundance of side shoots. Waltham 29 is adapted for both drought and cold tolerance. Minimum of 750 mg per packet (about 200 seeds).
- Productive - Waltham 29 Broccoli germinates in 7-14 days when soil temps are 70-75°F. Plant 1/4” deep and space 4-6” apart in an area with full sun. This variety will grow 20-24” tall with a spread of 12-16”. Heads will mature in 50-60 days, plant in USDA zones 3-10.
- Good Eats - Enjoy this delicious and nutritious broccoli raw, roasted, or added to soups, stir-fries, pastas, salads and more.
- Easy to Grow - Instructions included on each packet. Plus, we are available to answer all your questions. If these seeds don’t germinate, we will happily make it right for you.
- Safe and Sustainable - Our operation is fully solar powered, and Sow Right Seeds has taken the Safe Seed Pledge to sell only fresh Non-GMO heirloom seeds for you and your family.
Does broccoli kill bacteria or replace antibiotics?
“Inhibits growth” is more accurate than “kills” for these findings: the studies measured outcomes such as growth inhibition under test conditions, and the 2002 H. pylori study specifically described sulforaphane’s activity as bacteriostatic. None of the cited evidence establishes broccoli as an antibiotic substitute, a way to prevent foodborne illness, or a treatment for an infection.
If you suspect an infection, seek appropriate medical advice rather than trying to treat it with broccoli, sprouts, or supplements. Broccoli can be part of a normal diet, but the laboratory results do not tell you how much to eat, whether a particular preparation would work in your body, or whether it would affect a given infection.
Quick Recap
Rank #4
- Grow Garden Broccoli - Plant Waltham 29 for tight blue-green heads and smaller side shoots after the main harvest. This cool-season heirloom brings classic broccoli to vegetable beds and raised gardens.
- 250-Seed Yield Range - At a 20-70% productive-plant range and 1 lb average per plant, 250 seeds could yield about 50-175 LBS in good conditions; actual harvest varies with germination, weather, spacing, timing, and care.
- Start with Seeds - Sow 1/4-1/2 inch deep in individual starter pots or seed-starting cells. Aim for 70-80 F in the seed zone; emergence commonly takes 5-10 days under suitable conditions. Keep the mix moist with good drainage.
- Give Heads Room - Harden seedlings and transplant 18-24 inches apart in full sun. Time growth for cool weather, water evenly, and cut the central head while buds remain tight; smaller side shoots can follow.
- One Packet, Future Plantings - 250 Waltham 29 broccoli seeds in a waterproof RDR Seeds packet with growing guidance, dated for the current or next planting season. Store cool, dry and tightly sealed. Broccoli seed generally remains viable for about 3-5 years under good storage conditions; germination declines with age.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
The Tool Desk
Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →
