GUEST COLUMNIST: The Marvels of Medicinal Herbs

By Mike Blanco, Mary Friestedt, and Lan Lin.

Herbs! We love them. We grow them for food, for their scent, and as ornamentals. However, herbs are also important medicinally, and it is this aspect that brought participants at the Annual Natural Supplements Conference, sponsored by the Scripps Research Institute, to the San Diego Botanic Garden each year. There, as part of the Conference’s goal to present a “clinically relevant overview of natural supplements in evidence-based practice, with an emphasis on disease states,” they were treated to an exploration of the Herb Garden and its medically important collection. More recently, as the Conference has grown and interest in medicinal herbs expanded, the herbs have been travelling to the Conference. Docents at the Garden are now asked to bring samples of some of the more important herbs to share with conference participants.

As the three Docents involved in this effort, we have been fascinated to learn about the medicinal properties of plants that are so common in our Southern California gardens. Here are just some of the more interesting and unexpected herbs we collected for the Conference:

African Bulbine – Bulbine spp. – The fresh leaves, slimy leaf gel, and less commonly the roots of this plant contain anthraquinones and glycoproteins which can be used externally for skin conditions such as insect bites, cold sores, sunburn rashes, acne, ringworm, and blisters. In rat studies, the stems of Bulbine natalensis have been shown to boost testosterone levels. Studies on the efficacy for humans show promise for body builders (photo above).

Black Sage – Salvia mellifera – The leaves, stems, and seeds of this perennial herb contain diterpenoids as well as volatile oils, which are useful as a pain reliever for arthritis, rheumatism, and sore throats. Fresh leaves are used for bites and stings. When a Kumeyaay medicine woman visited SDBG was told she could take any herb from the Garden, she chose only Black Sage, presumably for her back pain.

Chili Pepper or Cayenne – Capsicum spp. – The dry and fresh fruits of this herb contain pungent capsaicin, carotenoids, vitamin C, flavonoids, and volatile oils which are effective in treating neuralgia, psoriasis, pain and joint tenderness, and circulation issues.

Cinnamon – Cinnamomum cassia – The bark, twigs, and dried flowers have volatile oils and cinnamaldehyde to counteract bacteria, fungi, and viruses.The anti-inflammatory and antioxidant properties are used for the treatment of diabetes, obesity, and high cholesterol.

Nevin’s Barberry or Mahonia – Berberis nevenii – The leaves, roots, and berries of this endangered California evergreen shrub contain the antimicrobial alkaloid berberine, which is used to treat chronic skin conditions, digestive problems, and amoebic dysentery.

Tea Tree – Melaleuca alternifolia – The leaves of this tree from Australia and New Zealand are composed of terpene hydrocarbons with monoterpenes, sesquiterpenes, and associated alcohols which are antiseptic and antimicrobial, and are successfully used for acne treatment, fungal infections, yeast infections, coughs, colds, and sore throats. Australians use the leaves to treat scabies and head lice.

Turmeric – Curcuma longa – Containing over 30 essential oils with analgesic, antioxidant, and anti-inflammatory plant properties, the plant’s rhizomes (roots) are used for arthritis, digestion, eczema, liver problems, pain, type 2 diabetes, as a cancer preventative, and more.

Thyme – Thymus vulgaris – The aromatic, antimicrobial, and antispasmotic leaves of this herb are used for upper respiratory infections, congested sinuses, urinary tract infections, topical fungal infections, and even toothaches.

Yerba Santa – Eriodictyon crassifolium – The leaves of this California native contain polysaccharides with mucilaginous properties and bioflavonoids, which are quite successful in treating respiratory illnesses and coughs. When the Spanish colonists first arrived in what is now California, they were so amazed with the healing properties of this shrub that they decided to call it Yerba Santa, or Holy Herb.

One of the best places to see these medicinal herbs is at the San Diego Botanic Garden. We hope to see you there.

This article was contributed by SDBG Docents: Mike Blanco, Ph.D., a plant scientist; SDHS member Mary Friestedt, an herb enthusiast and Master Gardener who regularly speaks on herbs; and Lan Lin, a registered nurse with an extensive knowledge of Asian herbs.