Tanner's Sumac - Rhus coriaria

Detailed Description

A time-honored herb with incredible potential, used for thousands of years.

Botanical Information

The sumac group consists of deciduous and evergreen, dioecious shrubs or trees. Some species can reach heights up to 30 meters. Tanner's Sumac, however, is a shrub growing up to 5 meters tall. It features spreading branches and pinnate leaves composed of up to 15 elliptic, pinnate, trifoliate, petiolate, or sessile leaflets.

The plant bears small, creamy-white, reddish, or greenish flowers, either sessile or with short stalks, five-petaled, arranged in dense compound panicles or spikes at the leaf axils or branch tips. Flowers have five stamens with awl-shaped filaments. Tanner's Sumac typically blooms from March or April. The fruit is a red or brown, spherical drupe containing a single seed.

The young twigs and leaves are harvested and, when dried, appear in shops whole, crushed, or ground into a gray-green powder. The plant's tannins are especially valued in Spain for processing goat skins into saffian and cordovan leathers.

Origin and Distribution

Tanner's Sumac is native to Southern Europe, especially Spain and Greece, where it still grows wild on rocky terrain, but is also cultivated for its high tannin content.

Most sumac species are native to the Americas, distributed from southern Canada to Panama and Cuba. In Europe, only Tanner's Sumac occurs naturally, ranging from the Canary Islands and throughout the Mediterranean to Afghanistan.

Usage / Dosage

During the Middle Ages (primarily the 13th to 15th centuries), sumac appeared in cookbooks used by wealthy people in Western Europe. In Arabic cuisine, ground sumac drupes are sprinkled on dishes like hummus and tahini, and are also commonly added to falafel. In Syria, sumac is a main ingredient in Kubah Sumakieh and is central to the Palestinian dish musakhan. In Afghan, Armenian, Bangladeshi, Iraqi, Indian, Iranian, Mizrahi, and Pakistani cuisines, sumac is used with rice, kebab, or salads.

Dried fruits of some sumac species are ground to make a tangy, crimson spice. The fruit is also used to make traditional "pink lemonade" by soaking in water with sweeteners. In North America, some sumacs are used for a beverage called "sumac-ade." Indigenous peoples use sumac leaves and drupes blended with tobacco in traditional smoking mixtures.

Besides its role as a tanning agent, sumac produces tart drupes (baccae sumachi) that have been used in the Middle East since ancient times for treating diarrhea and as a spice for meat dishes.

Folk Medicine

Many sumac species are used in traditional medicine for a variety of disorders and ailments. Some are applied for rheumatism, venereal diseases, diarrhea, coughs, sore throats, and against intestinal parasites.

Tanner's Sumac is used across the Middle East and South Asia for thousands of years as a traditional remedy for various illnesses, including cancer. The fruits have been traditionally used for treating liver diseases, diarrhea, urinary system problems, and ulcers.

Internally, sumac is utilized for chronic digestive disorders and blood in the stool; externally, for bleeding wounds, swelling, and skin infections. Ointments and suppositories for hemorrhoids are also produced from the herb.

Medicinal Properties

Sumac substances have demonstrated antioxidant, anti-inflammatory, hypoglycemic, and hypolipidemic effects. Leaves and bark of many species, including Tanner's Sumac, are rich in tannins. The leaves specifically contain pyrogallol-type tannins.

Antioxidant Activity

Various phytochemicals and phenolic compounds in sumac, known as secondary metabolites, have strong antioxidant properties. Thanks to their antioxidant activity, sumac may be useful in treating pathological disorders such as skin injury, myopathy, overweight, and obesity. The extract has been shown to protect skin from ultraviolet-induced damage.

Protection of myoblasts from oxidative stress can improve muscle function. In studies with human myoblasts and embryos, sumac extract exhibited robust antioxidant activity, inhibiting or slowing the progression of skeletal muscle atrophy, thanks to its effects on superoxide dismutase 2 and catalase.

Sumac's ability to inhibit reactive oxygen species (ROS) and digestive lipases demonstrates its potential in combating obesity. Lipases, especially pancreatic lipase (PL), are vital for fat digestion; inhibiting PL reduces fat absorption, representing a promising strategy for both the prevention and treatment of obesity. Studies, such as Jamous et al., have validated strong in vitro inhibition of PL by sumac leaves and fruit peel extracts.

Sumac extract has also shown significant antioxidant performance in DPPH, FRAP, CUPRAC, and ABTS tests.

Antiobesity Effects

A clinical study displayed significant weight loss, reduction of waist circumference, and BMI among obese patients supplementing with sumac. Through its antioxidant and PL-inhibiting activity, sumac offers valuable support in managing overweight and obesity. In laboratory studies with rat hepatocytes, sumac aqueous extract protected against oxidative stress from cumene hydroperoxide.

Further results indicate sumac extract can shield liver cells from various stressors, reduce glutathione depletion, and limit DNA damage across organs such as the colon, liver, and lungs. Notably, gallic acid, a sumac compound, is linked to its liver-protective effects.

DNA Protection

Sumac extract has demonstrated the capacity to significantly prevent and mitigate DNA damage from various oxidative and carcinogenic agents.

Antibacterial Effects

With growing bacterial resistance and limited availability of new antibiotics, the essential oil of Rhus coriaria has been recently studied for antibacterial activity against several strains. The oil effectively inhibits the growth of Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, and Bacillus subtilis at relatively low concentrations.

Ethanolic extract of sumac fruit showed broad-spectrum antimicrobial activity against both Gram-positive and Gram-negative bacteria. Notably, Salmonella enterica and Staphylococcus aureus were highly sensitive to the ethanolic extract. Methanolic and aqueous extracts also inhibited the growth of oral bacteria, including Streptococcus mutans, Streptococcus sanguinis, Streptococcus sobrinus, Streptococcus salivarius, and Enterococcus faecalis. These results align with traditional use of sumac for disinfection and demonstrate its potential in developing novel antimicrobials.

Antidiabetic Effects

Sumac's effect on type II diabetes has been studied by measuring serum glycemic status, apolipoprotein B, apolipoprotein A-I, and total antioxidant capacity. Patients taking 3.0 g of sumac powder daily for 3 months experienced significant reductions in serum glucose, HbA1c, ApoB, ApoA-I, and an increase in total antioxidant capacity.

In animal studies, sumac seed extract significantly lowered glucose and cholesterol levels in male mice with streptozotocin-induced type II diabetes. Dosing at 300 mg/kg resulted in decreased LDL cholesterol.

Cardioprotective and Antidyslipidemic Effects

In double-blind, randomized, placebo-controlled clinical studies involving patients with dyslipidemia, daily doses of 500 mg of sumac fruit over 4 weeks led to improved endothelial function and a significant reduction in systolic and diastolic blood pressure, total cholesterol, LDL cholesterol, and body mass index compared to placebo.

Meta-analyses have demonstrated that sumac has a positive influence on lipid profile indices, including increased Apo A-I and HDL, and decreased Apo B, total cholesterol, LDL, and triglycerides. The cardioprotective effect is further supported by studies indicating vasorelaxant and antihypertensive activities of ethanol extracts of sumac fruits.

Clinical research confirms that including sumac in the diet may lower blood pressure in hypertensive patients and be used as adjuvant therapy.

Anticancer Effects

Rhus coriaria has shown confirmed anticancer effects against various cancer types.

Breast Cancer

Ethanolic extract of sumac reduced cell viability of various breast cancer cell lines (MDA-MB-231, MCF-7, T47D) in a dose-dependent manner. It was found to induce DNA damage, irreversible G1 arrest, and cellular senescence, and to trigger programmed cell death (type II apoptosis). Additionally, sumac extract inhibits migration and invasion of aggressive breast cancer cells and in animal models, inhibits tumor growth and metastasis.

Sumac constituents such as quercetin are noted to lower cell viability and induce caspase-3 dependent apoptosis in several cancer cells, potentially contributing to its anticancer activity.

Colon Cancer

Ethanolic sumac extract reduced viability and colony growth of HT-29 colon cancer cells and suppressed tumor growth in mouse xenografts via induction of apoptosis and autophagy. Its role in colorectal cancer has been confirmed through use of specific protease inhibitors.

Uterine, Cervical Cancer, and Retinoblastoma

Anticancer activity of sumac against uterine cervical cancer and retinoblastoma cell lines has also been observed, though further research is needed in these areas.

Anti-inflammatory Effects

Sumac exhibits anti-inflammatory activity, as demonstrated by studies showing that fruit alcohol extract significantly reduces pro-inflammatory cytokines in joint synoviocytes and fluids.

Another study showed that sumac fruit extract accelerated wound healing in laboratory animals, attributed to increased collagen deposition, decreased MMP-8, and greater hydroxyproline content. These effects are suggested to derive from the anti-inflammatory action of sumac extract. Therapeutic potential for skin inflammation and reduction of inflammatory markers in breast cancer cells have also been documented.

Active Compounds

More than 200 different chemicals have been identified in Tanner's Sumac, including organic acids, phenolic acids, conjugated phenolic compounds, flavonoids, isoflavonoids, hydrolyzable tannins, anthocyanins, terpenoids, and other compounds such as butein, iridoids, and coumarin derivatives.

The composition of dried fruit primarily includes water (6–11.8%), essential oils (1.0%), proteins (2.3–2.6%), and fiber (14.6–22.15%). Main minerals found in the fruits are potassium, calcium, magnesium, phosphorus, iron, sodium, zinc, manganese, copper, and aluminum. Sumac contains vitamins like thiamine, riboflavin, pyridoxine, cyanocobalamin, niacinamide, biotin, and ascorbic acid, though most sumac species contain only trace amounts of vitamin C.

Traditional Dosage

An official dosage for sumac is not established and varies by indication and preparation. Liquid forms and tinctures are often taken at a dose of 6 drops three times daily before meals. Clinical and preclinical studies have most commonly used doses of 200–400 mg/kg of sumac extract per day.