Analysis of Serenoa Repens Extracts on Korean Market and Their Comparison to USP Saw Palmetto Extract Standards

Food Suppl Biomater Health. 2021 Jun;1(2):e26 https://doi.org/10.52361/fsbh.2021.1.e26 pISSN 2765-4362·eISSN 2765-4699

Brief Communication Analysis of Serenoa repens Extracts on Korean Market and their Comparison to USP Saw Palmetto Extract Standards

Ki Cheon Kim ,1 Min-Jun Choi ,1 Kyung-Mi Kim,1 W. Stephen Hill,2 Margaret Dohnalek,2 Stephanie Davis,2 Jae-Chul Jung 1

1Life Science Research Institute, NOVAREX Co., Ltd., Cheongju, Korea 2Valensa International, Eustis, FL, USA

Received: Jun 22, 2021 ABSTRACT Revised: Jun 27, 2021 Accepted: Jun 27, 2021 The lipid extract of the ripe berries of Serenoa repens also known as saw palmetto extract, can Correspondence: be used for relieving lower urinary tract symptoms (LUTS) associated with benign prostatic Jae-Chul Jung, PhD hyperplasia (BPH) in men as they age. A quality extract are rich in free fatty acids, long chain Research and Development & International Business, NOVAREX Co., Ltd., 94 Gangni 1-gil, alcohols and phytosterols and also has a clear appearance, dark brown color and pungent Ochang-eup, Cheongwon-gu, Cheongju 28126, odor. However, the saw palmetto products on the market in many countries other than USA Korea. fail to contain the amounts of the above components required to be effective for LUTS/BPH, E-mail: [email protected] and some products may even be adulterated with undeclared plant or animal-derived lipids. In this study, to find out the situation in Korea, four Korean products randomly selected from © 2021 Health Supplements Future Forum ® This is an Open Access article distributed the Korean market and USPlus extract, the first and only saw palmetto extract to meet the under the terms of the Creative Commons U.S. Pharmacopeia (USP) Dietary Ingredient Verification Program standards, for reference Attribution Non-Commercial License (https:// were analyzed for their ingredients using gas chromatography and compared for organoleptic creativecommons.org/licenses/by-nc/4.0/) characteristics such as color, appearance and aroma. The reference sample showed the levels which permits unrestricted non-commercial of the three components compared well to the standards indicated in the USP Saw Palmetto use, distribution, and reproduction in any medium, provided the original work is properly Extract monograph. On the other hand, the four Korean samples showed the levels of fatty cited. acids almost identical to those of the reference sample. However, the levels of long-chain alcohols in all the Korean samples were below the minimum 0.15% USP limit, with two ORCID iDs samples containing an almost undetectable level. Possibly, the Korean distributors prepared Ki Cheon Kim https://orcid.org/0000-0002-1188-8178 the products with a smaller amount of the quality extract. In contrast, the levels of sterols Min-Jun Choi were higher than those of the reference; most of the sterols was 1.4–2.0 times, particularly https://orcid.org/0000-0002-5794-0437 with campesterol up to 2 times higher and stigmasterol 3–6 times higher. Different from Jae-Chul Jung the clear, dark brown reference, the Korean samples were cloudy, yellow, colorless, fruity or https://orcid.org/0000-0001-9114-9756 even rancid. The different colors suggest the addition of synthetic chemicals or treatment Disclosure with bleaching earth/activated carbon. Fruity smell also suggests an addition of synthetic The authors have no potential conflicts of chemical. Rancid is indicative of age or improper storage conditions. All these differences in interest to disclose. organoleptic evaluation suggest the Korean products were subject to various treatments and/ or bad storage conditions, which may be associated the lower levels of the alcohols possibly Author Contributions Conceptualization: Kim KM, Jung JC; Data through alteration or decay under these conditions. The results of the present study raise a curation: Choi MJ, Hill WS, Dohnalek M; possibility that the Korean products were adulterated. To protect the consumers from this Formal analysis: Hill WS, Dohnalek M, illegal and unjustifiable act, the authors are proposing a preventive measure that will be an Davis S; Investigation: Hill WS, Dohnalek M; authenticity-certifying system employing the methods used in this study. Methodology: Hill WS, Dohnalek M; Project administration: Choi MJ, Kim KM, Davis S, Jung Keywords: Saw Palmetto; Serenoa repens; Adulteration; USP Monograph; Valensa https://e-fsbh.org 1/6 Current Issue of Adulteration in Saw Palmetto Extracts

JC; Resources: Dohnalek M; Supervision: Jung Saw Palmetto (Serenoa repens [W. Bartram] Small [Arecaceae]; Syn: Sabal serrulata, [Michx.] JC; Validation: Davis S; Writing - original draft: Nutt. ex Schult. & Schult. f.; Serenoa serrulata [Michx.] G. Nichols) is native to the Southeastern Kim KC, Choi MJ, Kim KM; Writing - review & United States.1 The plant annually produces a fruit (commonly called ‘berries’) in the summer editing: Kim KC, Jung JC. months. The ripe, dried berries are processed with supercritical CO2 to isolate a lipidosterolic extract. Due to its activity to inhibit 5-alpha-reductase thus, reducing androgenic activity, the extract has been used for maintaining normal prostate function and relieving some lower urinary tract problems associated with prostate enlargement known as benign prostatic hyperplasia (BPH) in the male elderly.2-4 Korea Ministry of Food and Drug Safety also recognized this extract as a health functional food ingredient to help prostate health.

Due to its increasing demand but limited wildcraft growing area, the extract is relatively expensive, therefore subject to economic adulteration in the marketplace.5 The most common method for adulteration is dilution and/or substitution with undeclared plant oils from coconut, palm, olive, and others.6 The current U.S. Pharmacopeia (USP) Saw Palmetto Extract monograph includes identification tests and limits based on the fatty acid profile and content of long-chain alcohols and phytosterols.7 These standards can be used as a basis for determining the authenticity of extracts in the market.6,7 Saw palmetto extracts also have a characteristic orange-brown color and distinctive pungent aroma which can be used to distinguish from other oils.8,9

The adulterated extracts of Saw Palmetto are known to be common in many countries including China and India.5,6 However, the adulteration status in Korea has not been investigated. In this study, to find out the situation in Korea, four Korean products randomly selected from the Korean market and USPlus® extract (Batch 200324; Valensa International, Eustis, FL, USA) for reference were analyzed for fatty acids, long chain-long alcohols and phytosterols. The results obtained were then compared to the standards in the USP Saw Palmetto Extract monograph. Also, the organoleptic characteristics (color, appearance, and aroma) were compared between the Korean products and the reference USA product.

Table 1 shows the results of the ratio of the lauric acid's concentration to the respective fatty acids' concentration in Korean and referenced extracts to compare the amount of respective fatty acids. The amount of each fatty acid was presented as the ratio to that of lauric acid which is known as a main functional ingredient of the Saw Palmetto extract and used as an indicator component. The USP monograph acceptance criteria limits for each are included for comparison. As shown in Table 1, the values obtained from the 4 Korean samples (marked with letter codes) and one USA reference sample (Batch 200324) compared well to the monograph limits, with only the samples J and V having palmitic acid slightly out of specification.

Table 2 shows the results of the analysis of long-chain alcohols. The amounts of long- chain alcohols were calculated from the ratio of the peak area of each relevant sterol in the sample solution to the peak area of the hexacosanol standard solution and presented as the percentage of alcohol in the total extract amount. All of the samples from the Korean products contained levels of long-chain alcohols below the minimum 0.15% USP limit, with two samples containing an almost undetectable level. The reference sample, Batch 200324 had 0.269% which is typical for a lipidosterolic extract of Serenoa repens.

Table 3 shows the results of phytosterol analysis. The amounts of the sterols were also calculated from the ratio of the peak area of each relevant sterol in the sample solution to the peak area of β-beta-sitosterol standard solution and presented as the percentage of sterol https://e-fsbh.org https://doi.org/10.52361/fsbh.2021.1.e26 2/6 Current Issue of Adulteration in Saw Palmetto Extracts

Table 1. Comparison of amounts of fatty acids between the Korean samples and reference sample Fatty acid Samples Lauric acid ratio* C G J V 200324 USP monograph Caproic acid 19 21 19 18 16 9.0–40 Caprylic acid 11 10 10 10 13 8.5–17.5 Capric acid 14 15 14 14 11 9.0–16 Myristic acid 2.5 2.6 2.7 2.7 2.6 2.2–2.8 Palmitic acid 3.4 3.3 4.4 4.0 3.5 2.8–3.9 Stearic acid 19 17 21 20 17 13–20 Oleic acid 1.06 1.06 1.04 1.02 0.98 0.60–1.15 Linoleic acid 5.8 5.9 5.6 5.7 5.9 4.0–8.0 Linolenic acid 56 54 59 56 41 35–60 These extracts of samples were prepared by supercritical extraction with carbon dioxide. The samples were prepared to analyze the contents of fatty acids by GC methods following the analysis recommended by USP monograph. The samples marked with letter codes were randomly selected from the Korean market and the reference sample was Batch 200324 of USPlus® extract of Serenoa repens from Valensa International). The USP monograph acceptance criteria limits for each are included for comparison. Each Sample was analyzed for the amount of each fatty acid using the procedures in the current USP43–NF38 Saw Palmetto Extract monograph and then the percent of each fatty acid was calculated. The numbers in the Table are the ratio of the percent of lauric acid to the percent of the nine other fatty acids (percent lauric acid/percent each fatty acid). USP = U.S. Pharmacopeia. *The fatty analysis of each sample was performed according to the procedures described in the current USP43–NF38 Saw Palmetto Extract monograph. Following the USP monograph, fatty acids were first esterified by methyl alcohol and the resulting fatty acid methyl esters were analyzed by gas chromatography. The standards of individual fatty acid methyl esters were obtained fromUSP. Gas chromatography column length 30 m; ID 0.32 mm; film thickness 0.25 µm; liquid phase USP phase G16. Instrument: PerkinElmer Clarus GC; FID detector. Percentage of each fatty acid was calculated from the peak response ratio of each relevant methyl ester in the standard solution relative to the sample solution. For comparison to the USP monograph identification criteria, the ratio of the concentration of lauric acid to the concentration of the nine other fatty acids was calculated.

Table 2. Comparison of levels of long-chain alcohols between the Korean samples and reference sample Alcohols Samples Percentage of alcohol in total extract (w/w) C G J V 200324 USP monograph Tetracosanol 0.001 0.012 0.001 0.002 0.004 - Hexacosanol 0.003 0.010 0.000 0.000 0.022 - Octacosanol 0.024 0.016 0.000 0.000 0.208 - Triacontanol 0.004 0.039 0.000 0.000 0.035 - Total alcohols 0.033 0.076 0.001 0.002 0.269 0.15–0.35 These extracts of samples were prepared by supercritical extraction with carbon dioxide. The samples were prepared to analyze the contents of fatty acids by GC methods following the analysis recommended by USP monograph. The same samples as in Table 1 were analyzed for the long-chain alcohols using the procedures in the current USP43–NF38 Saw Palmetto Extract monograph. Briefly, long-chain alcohols were silylation and the resulting derivatives were analyzed by gas chromatography. Percentage of long-chain alcohols was calculated from the peak response ratio of each relevant alcohol in the sample solution to the peak area in the hexacosanol standard solution. Hexacosanol standard was obtained from USP. Gas chromatography column length 25 m; ID 0.2 mm; film thickness 0.33 µm; liquid phase USP phase G1. Instrument: PerkinElmer Clarus GC; FID detector. The USP monograph acceptance criteria limit is included for comparison. USP = U.S. Pharmacopeia.

in the extract amount. In contrast to the long-chain alcohols, the four unknown samples contained total levels of sterols 1.4–2.0 times that found in the reference 200324 sample. The relative higher sterol level was not balanced across all sterols, but up to 2 times higher in campesterol and 3–6 times higher in stigmasterol.

Table 4 shows organoleptic evaluation of the samples in terms of color, appearance and aroma. Only the reference 200324 sample displayed both the typical brown color and pungent characteristic aroma. Sample C did have a characteristic color, but the aroma was faint. The ‘fruity’ aroma and yellow color of G was not typical of saw palmetto. Both J and V had rancid odors.

Valensa's USPlus® saw palmetto extract was chosen as a reference. The “Valensa” assures the following 4 things for her product. 1) Berries she used were harvested and extracted at the optimal time for maximum potency so that it meets or exceeds the recognized industry quality standards. 2) Thus, the Valensa's USPlus® extract exceeds the minimum requirements https://e-fsbh.org https://doi.org/10.52361/fsbh.2021.1.e26 3/6 Current Issue of Adulteration in Saw Palmetto Extracts

Table 3. Comparison of levels of phytosterols between the Korean samples and reference sample Sterols Samples Percentage of sterol in total extract (w/w) C G J V 200324 USP monograph Campesterol 0.128 0.057 0.144 0.133 0.061 - Stigmasterol 0.135 0.081 0.166 0.144 0.026 - β-sitosterol 0.260 0.271 0.262 0.249 0.195 NLT 0.1 Stigmastanol 0.013 0.010 0.012 0.013 0.010 - Total sterols 0.536 0.420 0.585 0.539 0.292 NLT 0.2 These extracts of samples were prepared by supercritical extraction with carbon dioxide. The samples were prepared to analyze the contents of fatty acids by GC methods following the analysis recommended by USP monograph. The same samples as in Table 1 were analyzed for sterols using the procedures in the current USP43–NF38 Saw Palmetto Extract monograph. Briefly, sterols were silylation and the resulting derivatives were analyzed by gas chromatography as described in Table 2. Percentage of sterols was calculated from the peak response ratio of each relevant sterol in the sample solution to the peak area in the beta-sitosterol standard solution. β-sitosterol standard was obtained from USP. USP = U.S. Pharmacopeia; NLT = not less than.

Table 4. Comparison of organoleptic evaluation of the 5 samples Organoleptic Samples C G J V 200324 Color Light brown Yellow Light brown Colorless Dark brown Appearance Clear Cloudy Clear Clear Clear Aroma Faint characteristic Faint fruity Rancid Rancid Characteristic, pungent The same samples as in Table 1 were evaluated in terms of color, appearance and aroma.

for USP standards in the levels of fatty acids, fatty alcohols and phytosterol levels (USP40– NF31, 2017). 3) The extract has also the proper concentration and fingerprint ratio of lauric acid to the concentration of other key fatty acids found in this unique berry. This ratio is a key determinant of saw palmetto extract quality and authenticity. 4) It has a typical brown color, clear and pungent aroma.10

The analysis data in the present study show that among the five extracts studied, only Valensa's USPlus® sample (Batch 200324) contained the complete profiles of fatty acid, phytosterol and long-chain alcohol meeting the standards of USP monograph. On the other hand, the four samples from the Korean distributors show that only the contents of fatty acids were comparable to those of the reference sample but the contents of long-chain alcohols were very low and the contents of sterols were very high compared to those of the reference sample. While the reference sample was clear, dark brown and characteristically pungent, the Korean versions are cloudy, fruity, light brown, yellow or even rancid.

Of the three components examined, the four Korean samples shows that only the contents of fatty acids compared well to those of the reference sample (Batch 200324). Thus, these data suggest that Korean distributors manufactured the products using the quality extract prepared from the good berries. However, the 4 samples showed the much higher levels of sterols, most of which were 1.4–2.0 times but some of which were more than 2–6 times the levels found in the reference sample. These higher, unbalanced levels of sterols suggest addition of exogenous plant lipid fractions rich in sterols.

In contrast to the sterol, interestingly, the levels of long-chain alcohols were much lower, even below the minimum 0.15% USP limit or with even an almost undetectable level in some samples. It is difficult to guess why levels of long-chain alcohols are low in the Korean samples. One possibility is that the four Korean products were manufactured with a smaller amount of the quality extract.

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While the reference sample was clear, dark brown and characteristic pungent, the Korean products are colorless, light brown, yellow, cloudy, fruity or even rancid. The different colors suggest the addition of synthetic dye or treatment with bleaching earth/activated carbon. Fruity smell also suggests an addition of synthetic chemical. Rancid is indicative of age or improper storage conditions. All these differences in organoleptic evaluation suggest the Korean products were subject to various treatments and/or bad storage conditions. Under these conditions, the sterols may be changed or decayed through unknown processes or mechanisms. This may be a second possibility for the low levels of the sterols.

Through the present study, it is found out that all the samples from the Korean market were quite different from the reference sample in the levels of ingredients and organoleptic characters. Thus, it is highly suggested that they were adulterated possibly through using a smaller amount of the quality extract, addition of exogenous plant lipid fractions rich in sterols, addition of synthetic dye and flavoring or treatment with bleaching earth/activated carbon and/or bad storage conditions.

Since adulteration is an illegal act to deceive consumers and cause harm to them, it is needed to prepare preventive measures. Thus, the authors would like to propose to adopt a certification system that informs the consumers of the product authenticity. To establish this system, we propose the following steps more specifically. 1) The distributors in Korea first must form a league and the league agrees to adopt this system. 2) As criteria to determine the authenticity, the content and profile of fatty acids, long-chain alcohols and sterols and organoleptic characteristics shall be used. 3) The league shall prepare a laboratory equipped with the facility that can perform the assays for the above materials. 4) This laboratory shall be operated by a third party (for instance, Korea Health Supplement Association) unaffected by the league. 5) The third party shall have rights to sample the product randomly, perform the identification test and have the permission to determine the authenticity. 6) The distributors shall display the sign of test-pass on the products. It is hoped that the authorities concerned accept this this proposal and reflect it in the government policy-making.

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