Kelli Herrlinger

Phenolic and Volatile Composition of a Dry Spearmint (Mentha spicata L.) Extract

The present paper reports a complete mass spectrometric characterization of both the phenolic and volatile fractions of a dried spearmint extract. Phenolic compounds were analysed by ultra-high performance liquid chromatography-electrospray ionization-mass spectrometry (UHPLC-ESI-MSn) and a total of 66 compounds were tentatively identified, being the widest phenolic characterisation of spearmint to date. The analysis suggests that the extract is composed of rosmarinic acid and its derivatives (230.5 ± 13.5 mg/g) with smaller amounts of salvianolic acids, caffeoylquinic acids, hydroxybenzoic acids, hydroxycinnamic acids, flavones, and flavanones. Head space solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) technique, that was applied to characterize the volatile fraction of spearmint, identified molecules belonging to different chemical classes, such as p-cymene, isopiperitone, and piperitone, dihydroedulan II, menthone, p-cymen-8-ol, and β-linalool. This comprehensive phytochemical analysis can be useful to test the authenticity of this product rich in rosmarinic acid and other phenolics, and when assessing its biological properties. It may also be applied to other plant-derived food extracts and beverages containing a broad range of phytochemical compounds.

Phytochemical Profiling of Flavonoids, Phenolic Acids, Terpenoids, and Volatile Fraction of a Rosemary (Rosmarinus officinalis L.) Extract

This paper presents a comprehensive analysis of the phytochemical profile of a proprietary rosemary (Rosmarinus officinalis L.) extract rich in carnosic acid. A characterization of the (poly)phenolic and volatile fractions of the extract was carried out using mass spectrometric techniques. The (poly)phenolic composition was assessed by ultra-high performance liquid chromatography-electrospray ionization-mass spectrometry (UHPLC-ESI-MSn) and a total of 57 compounds were tentatively identified and quantified, 14 of these being detected in rosemary extract for the first time. The rosemary extract contained 24 flavonoids (mainly flavones, although flavonols and flavanones were also detected), 5 phenolic acids, 24 diterpenoids (carnosic acid, carnosol, and rosmanol derivatives), 1 triterpenoid (betulinic acid), and 3 lignans (medioresinol derivatives). Carnosic acid was the predominant phenolic compound. The volatile profile of the rosemary extract was evaluated by head space solid-phase microextraction (HS-SPME) linked to gas chromatography-mass spectrometry (GC-MS). Sixty-three volatile molecules (mainly terpenes, alcohols, esters, aldehydes, and ketones) were identified. This characterization extends the current knowledge on the phytochemistry of Rosmarinus officinalis and is, to our knowledge, the broadest profiling of its secondary metabolites to date. It can assist in the authentication of rosemary extracts or rosemary-containing products or in testing its bioactivity. Moreover, this methodological approach could be applied to the study of other plant-based food ingredients.

The safety of a dry spearmint extract in vitro and in vivo

A proprietary dry spearmint extract containing 15.4% rosmarinic acid was assessed in a 90-day study with Sprague-Dawley rats that were gavaged at 0, 422 (low), 844 (mid), or 1948 (high) mg dry spearmint extract/kg bw/day, (equivalent to 0, 65, 130, or 300 mg rosmarinic acid/kg bw/day, respectively). No treatment-related clinical signs or adverse effects were observed in body weight, feed consumption, neurological parameters, hematology, clinical chemistry, gross pathology, and histopathology. However, there were statistically significant increases in the absolute and relative weight of the pituitary gland in mid- and high-dose males, absolute and relative weight of the thyroid gland in the high-dose groups of both sexes and in mid-dose males, and absolute and relative weight of the salivary glands in high-dose females compared to vehicle control group. These changes were considered non-adverse since no corresponding microscopic changes were seen. Based on these findings, the no-observed-adverse-effect level (NOAEL) for the dry spearmint extract was 1948 mg extract/kg bw/day, the highest dose tested, in Sprague-Dawley rats. In addition, the extract showed no mutagenic activity in the Ames assay using Salmonella typhimurium strains (TA98, TA100, TA102, TA1535, and TA1537) and did not induce chromosomal aberrations when tested with human peripheral blood lymphocytes.

Supplementation with a polyphenolic blend improves post-exercise strength recovery and muscle soreness

Background Exercise can initiate a cascade of inflammatory and oxidative stress–related events leading to delayed onset muscle soreness. Polyphenols possess antioxidant and anti-inflammatory properties. Objective The current study examined the effects of a proprietary polyphenolic blend (PB), containing catechins and theaflavins, on exercise performance and recovery following an eccentric exercise challenge. Design Male participants (18–35 years of age) received placebo or PB at a low dose (PB-L, 1,000 mg/d) or high dose (PB-H, 2,000 mg/d) for 13 weeks. During the 13th week of supplementation, participants completed an eccentric exercise (40 min downhill treadmill run) followed by a strength assessment (peak torque on isokinetic leg extensions) pre-exercise, and 24, 48, and 96 h post-exercise. Muscle soreness (subjective questionnaire), markers of muscle stress (cortisol and creatine phosphokinase [CK]), and antioxidant capacity (ferric reducing ability of plasma [FRAP]) were also assessed. Results PB-H attenuated the decrease in peak torque observed in the placebo group from pre-exercise to 48 h (p=0.012) and 96 h (p=0.003) post-exercise. At 48 h post-exercise, PB-H reduced whole body and hamstring soreness (p=0.029) versus placebo. Chronic consumption of PB improved serum FRAP (p=0.039). As expected, serum cortisol and CK increased from pre- to post-exercise in all groups; however, by 96 h, cortisol and CK levels returned to pre-exercise levels following PB supplementation. At 96 h, the change in cortisol from pre- to post-exercise was significantly greater in placebo versus PB-H (p=0.039). Conclusion These findings show that chronic consumption of PB improved antioxidant status, reduced markers of muscle stress, and promoted strength recovery post-exercise.

Safety and tolerability of a dried aqueous spearmint extract

&NA; Spearmint (Mentha spicata L.) and spearmint extracts are Generally Recognized as Safe (GRAS) for use as flavoring in beverages, pharmaceuticals, and confectionaries. Studies of spearmint extracts in humans and animals have reported conflicting results with respect to toxicity. Since the chemical composition of these extracts was not reported and the spearmint source material was different, the relevance of these existing data to evaluating the risks associated with ingestion of a dried aqueous spearmint extract standardized to rosmarinic acid is not clear. Hence, the safety and tolerability of the dried aqueous spearmint extract was evaluated as part of a double‐blind, randomized, placebo‐controlled trial in healthy adults with age‐associated memory impairment. Ingestion of both 600 and 900 mg/day for 90 days had no effect on plasma levels of follicular stimulating hormone, luteinizing hormone, or thyroid stimulating hormone, or other safety parameters including vital signs, plasma chemistry or whole blood hematology values. Additionally, there were no reported severe adverse events, no significant between‐group differences in the number of subjects reporting adverse effects and the adverse events reported could not be attributed to ingestion of the extract. These results therefore show that ingestion of the aqueous dried spearmint extract is safe and well‐tolerated. Graphical abstract Figure. No caption available. HighlightsIn a 90‐day randomized clinical trial, safety of a spearmint extract was assessed.Placebo, 600 and 900 mg spearmint extract containing rosmarinic acid were tested.The extract had no effect on FSH, LH, TSH, vital signs and blood chemistries.There were no treatment‐related or between‐group differences for adverse events.The extract is safe and well‐tolerated under the conditions of use described.