Grape Seed (Extract) Kills Germs

(Updated April 20, 2020)

Grapes have been around for a long time, their attributes being praised by the Egyptians six thousand years ago. The healing powers of grapes had been tapped by the ancient Greeks, usually in the form of wine. Folk healers in Europe used the leaves and sap from the vines to treat skin and eye diseases and to stop the inflammation and pain from hemorrhoids. The substances inside the grape, oligomeric proanthocyanidin compounds (OPCs), are powerful anti-oxidants believed to be able to treat a number of human maladies, from heart disease to cancer to aging skin. Regardless of whatever research can support these uses, there is considerable evidence that grape seed extract is able to address venous insufficiency and edema (Kalus, 2004) (Schaefer, 2003) (Kiesewetter, 2000).

The seeds of grapes are loaded with vitamin E, linoleic acid (an omega-6 fatty acid), various flavonoids (including epicatechin, epicatechin gallate, epigallocatechin gallate, quercitin, kaempferol, and luteolin, among others) and OPCs (USDA, 2003). These compounds are also found in the juice, skins and wine, but in lower concentrations.   Related to the OPCs, resveratrol is the most recently heralded of the grape compounds, and is the subject of several human clinical trials (U.S. NIH), where it’s being studied for use in Alzheimer’s disease, type 2 diabetes, obesity, vascular health, and a raft of other conditions. Only recently announced is that grape seed extract has antimicrobial properties that appear to be more successful than some (or even all) drugs of that class.

One of the most ubiquitous microbes, which causes more than ninety percent of gastrointestinal illnesses worldwide, is the Norovirus. Norovirus-induced gastroenteritis is often called intestinal flu, although the influenza virus is not associated with this illness. Norovirus is transmitted by fecal contamination of food or water, by person-to-person contact, or by airborne means, where it may land on doorknobs, computer keyboards and other surfaces. The flush of a toilet can do this. A disgusting thought is that some of this virus can land on a toothbrush if it’s kept close enough to the toilet when the silver handle is depressed while the seat is up. Long-term care facilities are notorious venues for transmission (Said, 2008). You’ve seen the sign on the mirror in the public lavatory that reminds employees to wash their hands before returning to work. Some pay attention, some do not. Maybe this is a legitimate reason to pray over your food.

Norovirus may be inactivated with bleach (Tuladhar, 2012), but that’s not something you carry around. Because the virus is not girded by a lipid coat, neither alcohol nor detergents are effective biocides. That possibly includes those little moist towels that come in foil packets. As odd as it may seem, grape seed extract (GSE) has shown itself effective against Norovirus. The shell that protects the nucleic acid of a virus is called a capsid, which is a protein. GSE has the uncanny ability to denature that protein and to render the virus inactive. In laboratory tests, Norovirus cells that were exposed to GSE clumped together, deformed and inflated, reducing the virus’ binding capability and infectivity (Li, 2012). When GSE-treated water was used to wash freshly cut lettuce, similar results were noted. But GSE’s potential doesn’t stop here.

Staphylococcus denotes a group of spherical bacteria that aggregate in clusters, like grapes. They’re part of the normal micro-organisms that congregate on the skin and upper respiratory tract. Being gram-positive, they endure on dry surfaces. The strain of this bacterium most significant to humans is S. aureus, which forms a large yellow colony in its host and exhibits a facultative character, meaning that it can survive either with or without oxygen. Most of us carry S. aureus as a ubiquitous flora located in the armpits (axillary), groin (inguinal), the outer section of the nostrils (anterior nares), and the anus (perineum). Some of us carry this bacterium intermittently with changing strains; a minority not at all. Many, if not most, cases of S. aureus illness originate from nasal colonies (von Eiff, 2001). Oddly, this circumstance, identified as MRSA (methicillin-resistant S. aureus), may be attenuated by drinking coffee or tea. It was found that coffee and tea drinkers were fifty percent less likely to carry the bacterium in their nostrils than those who did not imbibe (Matheson, 2011).

Seeking compounds against S. aureus is an ongoing challenge. However, there is hope in GSE, a complex able to inhibit the enzyme needed by the bacterium to grow. In a Taiwanese experiment, fish that were exposed to the pathogen in their environment were spared infection when pre-incubated with GSE, prompting the scientists to foresee the extract as a viable means to prevent food poisoning caused by this bacterium (Kao, 2010). Electron microscopy examination of S. aureus after exposure to GSE noted disruption of the cell wall and a distinct bactericide effect (Al-Habib, 2010). In bacterial skin conditions, S. aureus was found to be most susceptible to the bactericidal nature of GSE (Abtahi, 2011).

In an era where bacteria are learning to resist the drugs designed to eliminate them, research is looking to add natural sources to its armamentarium. Some believe that a natural villain cannot escape a natural hero, regardless of villainous mutations. Hospital-acquired (nosocomial) MRSA infections have increased in recent decades, becoming the leading cause of pneumonia and operative wound infections, and the second most common cause of bloodstream infections. Antibiotic resistance is disturbing, particularly among children (Frei, 2010), but there is evidence that blood and skin infections are on the wane (Landrum, 012). With increasing signs that GSE (and now pomegranate polyphenols) alters S. aureus cell walls to the point of destruction, the only aspect left to be investigated is safety (Su, 2012). This is usually not a major concern with ingredients found in common foods, but may be an issue with the more exotic and foreign elements.  Grape seed extract is held to be safe when used in appropriate dosages (ECFR) (Food Navigator, 2001) (Kiesewetter, 2000). From treating E. coli (Quinones, 2011) to Listeria (Sivarooban, 2007) to Campylobacter (Silvan, 2013) to a collection of enteric pathogens (Su, 2011) (Xiaowei, 2011), the compounds in grape seed extract have earned a place of honor in the medicine cabinet.

Cytokine Storm and COVID-19

Of late, we are inundated with news of a cytokine storm initiated by a strain of the corona virus.  This type incites a vigorous inflammatory response that overwhelms the immune system with interleukins, notably the pro-inflammatory IL-1β, IL-2 and IL-8.  Recent Korean research found that GSE reduces the transcription of pro-inflammatory cytokines in airway epithelial cells, thus forestalling a disease outcome (Kim, 2019).  These syncytial viruses almost always result in pneumonia, and even COPD.  With no reliable vaccines available, we reach for straws. Here, GSE suppresses viral signaling capacity by hindering activity of the prototypical pro-inflammatory signaling compound, nuclear factor kappa B, NF-kB (Lee, 2017).