Rubus coreanus

Rubus coreanus (Korean black raspberry) is a berry from the raspberry family yet contains such a large content of anthocyanins that it is seen as nutritionally comparable to blueberry and related berries. When looking at Korean black raspberries though, they seem to carry bioactives from the raspberry family as well as the anthocyanins making them (in all practical terms) some manner of naturally occurring hybrid.

The berries are a commerical product in Korea for the most part (hence the name) and are used to make jams, jellies, food products, and most notably a wine called bokbunja ju. The unripe berries (not so much the ripe, since whatever main bioactive is in there seems to decline during the aging process) are a medicinal product for blood flow and circulation as well as male sexuality (aphrodisia and erectile function).

When looking at the berries, they are for the most part comparable to blueberries or aronia melanocarpa due to being a good source of anthocyanins. There are some unique properties of these berries though, and they seem to be related to calcium metabolism. Specifically, the berries reduce calcium release from the sarcoplasmic reticulum of cells when it would otherwise be stimulated (in a manner that can drop below baseline levels if high enough in concentration) and due to this the contraction seen in vessels including the penis that would normally occur from calcium release is attenuated.

A rat study has noted abnormally high increases in testosterone (700%) but such an increase has failed in the pilot study on healthy men. We cannot fully conclude that a testosterone boost cannot occur in men (since there were difference in the sources of the berry, stage of ripening, and dosage) but at this moment it does not look too promising.

Also tied into the testosterone would be an increase in spermatogenesis and sperm motility seen in male rats fed the unripe berries, which oddly seems to occur without changes in testicular size. This has not yet been tested in humans.

The one human study on the subject matter used 30g of the freeze dried berries and noted antioxidative and liver benefits associated with that dose. For the food product it is probably a good starting point, and there is not enough information to assess if one can use bokbunja ju for health reasons.

Many other studies in rats use the supplemental doses of 100-500 mg/kg of the unripe berry powder. In human terms, this gives us estimates of (the following is dry weight of the berry):

• 1,100-5,450 mg for a 150lb person

• 1,450-7,300 mg for a 200lb person

• 1,800-9,000 mg for a 250lb person

If using unripe berries with a water content, it will need to be recalculated.

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what effects rubus coreanus has on your body, and how strong these effects are.

Grade	Level of Evidence [show legend]
	Robust research conducted with repeated double-blind clinical trials
	Multiple studies where at least two are double-blind and placebo controlled
	Single double-blind study or multiple cohort studies
	Uncontrolled or observational studies only

Level of Evidence ? The amount of high quality evidence. The more evidence, the more we can trust the results.	Outcome	Magnitude of effect ? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.	Consistency of research results ? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.	Notes
	Anti-Oxidant Enzyme Profile	Minor	- See study	There appears to be a mild increase in glutathione peroxidase with no significant influence on catalase nor SOD in otherwise healthy men.
	Lipid Peroxidation	Minor	- See study	In otherwise healthy men with no apparent health problems, there is a mild decrease in lipid peroxidation associated with consumption of the berries (12% reduction in MDA)
	Liver Enzymes	Minor	- See study	In otherwise healthy men with no health problems, the mild reduction in lipid peroxidation seen was associated with a mild reduction in circulating ALP levels (6%) although AST and GST were unaffected.
	Blood Glucose	-	- See study	No significant alterations in fasting blood glucose are noted with daily berry consumption in otherwise healthy persons.
	C-Reactive Protein	-	- See study	In otherwise healthy men, there are no changes in C-reactive protein levels seen with berry consumption.
	HDL-C	-	- See study	No significant influence of the berries on HDL cholesterol levels in men who are otherwise healthy.
	LDL-C	-	- See study	No significant influence of rubus coreanus on LDL cholesterol levels in otherwise healthy persons.
	Testosterone	-	- See study	Despite the highly promising evidence in rats, there is no significant influence of the berries on testosterone levels of otherwise healthy men.
	Total Cholesterol	-	- See study	Currently the only study is in otherwise healthy men with no cholesterol problems, and there was no influence of berry consumption.
	Triglycerides	-	- See study	No significant influence of this berry on the triglycerides of otherwise healthy men.