New research finds that an herb considered by some to be a weed removes the ability of Candida to expand its germ tube. It joins other herbs that have been shown in research to stop candida growth.
The researchers, from South Africa’s University of the Witwatersrandm, collected Candida albicans cultures from the mouths of multiple HIV infected persons. They then cultured them in the lab using agar dextrose – as candida feeds off of sugars.
The researchers then produced an extract from the leaves of the hopseed plant – Dodonaea viscosa var. angustifolia (a bush with common names hopbush and sand olive). They harvested the leaves fresh. The extract was then applied to the candida cultures in three different concentrations. The researchers then analyzed the cultures using electron microscopes, and measured the growth of the cultures within their respective cultures.
Candida albicans grows via a process called germ tubes — also called hyphal. Germ tubes are illustrated above — the left image above shows the yeast cells while the right image shows the formation of the germ tubes.
These tubular channels will reach out into the environment as the cells expand in a process considered germination (hence the shortened term “germ”). Because these germ tubes are difficult to stop once they form, the process of candida growth is often considered to be “virulent” (though there is no actual virus). The point is that infections with the growth of Candida albicans has been difficult to treat by conventional medicine.
This is because the various antifungals used to treat candida infections quickly succumb to resistance, as the yeast will adapt to the antimicrobial — forming its germ tubes despite of the antifungal chemical.
The problem is that these antifungals do not attack the ability of the candida yeast to produce those germ tubes.
The researchers found that all three concentrations of the hopseed extract inhibited the growth of the candida yeast cultures — by eliminating their ability to produce germ tubes. The blocking of the germ tube growth occurred at 85%, 62% and 27% at the three different concentrations.
The researchers concluded with a clear statement:
“In conclusion, the plant extract of Dodonaea viscosa var. angustifolia reduces hyphae and biofilm formation in C. albicans which could be a result of damage to the cell wall. Hyphal (germ tube) and biofilm formation are important interrelated virulence factors in the pathogenesis of candidal infections.”
This is not the first study from South Africa that showed that hopseed inhibited the growth of Candida albicans. A study from 2008 also illustrated that hopseed blocked the growth and virulence of candida. But this study illustrated its unique abilities to block candida growth from the germ tube.
The reason this topic is of great concern to South African scientists is that among HIV infected individuals, candida infections are particularly nasty and dangerous. An HIV-infected person has a reduced immunity that can make candida growth difficult to stop.
The candida infection typically occurs from an infection of Candida albicans, but it is thought that approximately 15% if candida infections come from C dubliniensis — a close relative.
Most candida infections occur in the oral cavity (mouth), the esophagus (throat) or the vagina. HIV-infected persons typically battle candida infections that occur in the throat.
Other herbs have also been found to inhibit candida. These include Baicalein, a flavone found from Baikal skullcap (Scutellaria baicalensis) roots. Another herb proven to combat Candida is Cassia (Senna) spectabilis – also called Gold tree. Other herbs shown in research to inhibit candida include Houttuynia cordata (Chameleon), Prunus pendula (Weeping cherry tree), Cortex moutan (Paeonia suffruticosa), Cortex pseudolaricis (Pseudolarix kaempfri), Rhizoma alpiniae officinarum (Alpinia officinarum), Rhizoma coptidis (Coptis chinensis – Gold thread), Cloves (Syzygium aromaticum), Cinnamon (Cinnamomum verum) and others.
It should be mentioned that these herbs have been shown to inhibit candida, but not necessarily cut off the candida germ tubes as does the hopbush extract. It doesn’t mean that they don’t, however.
Nature provides its own enforcement mechanisms.
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