Natural food preservatives in the form of herb extracts and spices are increasing in popularity due to their potential to replace synthetic compounds traditionally used as food preservatives. Rosemary (Salvia rosmarinus) is an herb that has been traditionally used as an anti-inflammatory and analgesic agent, and currently is being studied for anti-cancer and hepatoprotective properties. Rosemary also has been reported to be an effective food preservative due to its high anti-oxidant and anti-microbial activities. These properties allow rosemary prevent microbial growth while decreasing food spoilage through oxidation. Rosemary contains several classes of compounds, including diterpenes, polyphenols, and flavonoids, which can differ between extracts depending on the extraction method. In particular, the diterpenes carnosol and carnosic acid are two of the most abundant phytochemicals found in rosemary, and these compounds contribute up to 90% of the anti-oxidant potential of the herb. Additionally, several in vivo studies have shown that rosemary administration has a positive impact on gastrointestinal (GI) health through decreased oxidative stress and inflammation in the GI tract. The objective of this review is to highlight the food preservative potential of rosemary and detail several studies that investigate rosemary to improve in vivo GI health.
The Mediterranean diet has long been known to provide a variety of health benefits such as cardiovascular protection, cancer prevention, and lowering gastrointestinal inflammation. Oregano (Origanum vulgare) is an herb prominent in the Mediterranean diet, and has been shown to possess several bioactive properties including anti-oxidant, anti-microbial, anti-inflammatory, and analgesic properties. The anti-oxidant and anti-microbial properties of oregano also make it a strong candidate as a natural food preservative. Because of the recent public concern with synthetic food preservatives, natural alternatives are increasingly being evaluated for effective food preservation. Oregano extract (OE) and essential oil (OEO) are two such agents that have shown promise as natural food preservatives. Additionally, oregano is being evaluated for its positive effect on gastrointestinal health, suggesting an additional benefit of food preservation with oregano. This review will describe in vitro studies related to the anti-microbial and anti-oxidant properties of oregano along with food preservation studies with oregano in various model food matrices. The major phytochemical content reported for OE and OEO will also be outlined to highlight the importance of characterizing the extract that is used, since the extraction process can have a significant effect on the phytochemicals therein. Finally, in vivo studies that investigate the gastrointestinal health benefits of oregano, specifically against inflammation, will be addressed to show the impact of oregano on gastrointestinal health.
Adipose tissue inflammation is associated with obesity comorbidities. Reducing such inflammation may ameliorate these comorbidities. n-3 fatty acids have been reported to have anti-inflammatory properties in obesity, which may modulate this inflammatory state. In the current study a 1 gram per day oral supplement of the n-3 fatty acid docosahexaenoic acid (DHA) was administered for 12 weeks to 10 grade 1-2 obese postmenopausal women and markers of adipose tissue and systemic inflammation measured and compared before and after supplementation. DHA administration resulted in approximately a doubling of plasma and red cell phospholipid and adipose tissue DHA content but no change in systemic markers of inflammation, such as circulating C-reactive protein (CRP) or interleukins (IL) 6, 8 and 10 (IL-6, IL-8, IL-10). DHA supplementation did not alter the adipose tissue marker of inflammation crown-like structure density nor did it affect any gene expression pathways, including anti-inflammatory, hypoxic and lipid metabolism pathways. The obese postmenopausal women studied were otherwise healthy, which leads us to suggest that in such women DHA supplementation is not an effective means for reducing adipose tissue or systemic inflammation. Further testing is warranted to determine if n-3 fatty acids may ameliorate inflammation in other, perhaps less healthy, populations of obese individuals.