Effects of capsaicin on rumen fermentation under normal and acidosis pH conditions: A comparative Rusitec study with monensin

Melis Unler; Hakan Öztürk

doi:10.33988/auvfd.1892357

Effects of capsaicin on rumen fermentation under normal and acidosis pH conditions: A comparative Rusitec study with monensin

Abstract

Capsaicin (CAP), the pungent component of chili peppers, possesses antimicrobial activity against a broad range of bacteria. This study evaluated the in vitro effects of CAP on ruminal fermentation under normal and acidic (SARA) pH conditions using the Rusitec system, in comparison with monensin (MON). By isolating pure capsaicin and applying a controlled dual-pH design, this study addresses uncertainty regarding CAP’s specific regulatory role in the rumen, thereby distinguishing its effects from those of complex phytochemical blends. The 18-day trial included adaptation, normal fermentation, and acidosis phases. CAP was tested at 1, 5, and 25 mg/L alongside MON (5 mg/L) under a high-concentrate diet (20:80). CAP significantly reduced ruminal pH at all doses, while SARA induction caused a clear phase-dependent pH decline in all fermenters. Total volatile fatty acids (VFA) production was unaffected by treatments but decreased during acidosis. MON increased propionate under both pH conditions, whereas CAP showed no effect. Only the CAP5 and CAP25 groups had higher methane production than the MON group. Protozoal counts were lowest in the MON group. NH₃-N and dry matter digestibility declined solely due to acidosis. Overall, at the tested doses, CAP exerted minimal influence on ruminal fermentation compared with MON.

Keywords

Project Number

15L0239005

References

Alabi JO, Okedoyin DO, Wuaku M, et al (2025): Untargeted metabolomics of dairy cows as influenced by the combinations of essential oil blends and fumaric acid as natural feed additives using RUSITEC. Metabolites, 15, 681. DOI: 10.3390/metabo15100681
An Z, Luo G, Abdelrahman M, et al (2022): Effects of capsicum oleoresin supplementation on rumen fermentation and microbial abundance under different temperature and dietary conditions in vitro. Front Microbiol, 13, 1005818. DOI: 10.3389/fmicb.2022.1005818
Brito Da Silva R, Pereira MN, Canonenco De Araujo R, et al (2020): A blend of essential oils improved feed efficiency and affected ruminal and systemic variables of dairy cows. Transl Anim Sci, 4, 182-193. DOI: 10.1093/tas/txz183.
Busquet M, Calsamiglia S, Ferret A, et al (2005): Screening for the effects of plant extracts and active compounds of plants on dairy cattle rumen microbial fermentation in a continuous culture system. Anim Feed Sci and Tech, 124, 597-613. DOI: 10.1016/j.anifeedsci.2005. 03.008
Callaway TR, Edrington TS, Rychlik JL, et al (2003): Ionophores: Their use as ruminant growth promotants and impact on food safety. Curr Issues Intest Microbiol, 4, 43-51.
Calsamiglia S, Busquet M, Cardozo PW, et al (2007): Invited review: essential oils as modifiers of rumen microbial fermentation. J Dairy Sci, 90, 2580-2595. DOI: 10.3168/jds.2006-644
Cardozo PW, Calsamiglia S, Ferret A, et al (2004): Effects of natural plant extracts on protein degradation and fermentation profiles in continuous culture. J Anim Sci, 82, 3230-3236. DOI: 10.2527/2004.82113230X
Cardozo PW, Calsamiglia S, Ferret A, et al (2006): Effects of alfalfa extract, anise, capsicum and a mixture of cinnamaldehyde and eugenol on ruminal fermentation and protein degradation in beef heifers fed a high concentrate diet. J Anim Sci, 84, 2801-2808. DOI: 10.2527/jas.2005-593

Castillo-Lopez E, Rivera-Chacon R, Ricci S, et al (2021): Short-term screening of multiple phytogenic compounds for their potential to modulate chewing behavior, ruminal fermentation profile, and pH in cattle fed grain-rich diets. J Dairy Sci, 104, 4271-4289. DOI: 10.3168/jds.2020-19521
1Chaney Al, Marbach EP (1962): Modified reagents for determination of urea and ammonia. Clin Chem, 8, 130-132. DOI: 10.1093/clinchem/8.2.130
Chen G, Russell JB (1988): Fermentation of peptides and amino acids by a monensin-sensitive ruminal peptostreptococcus. Appl Environ, Microbiol, 54, 2742-2749. DOI: 10.1128/AEM.54.11.2742-2749.1988
Czerkawski JW, Breckenridge G (1977): Design and development of a long term rumen simulation technique (Rusitec). Br J Nutr, 38, 371-384. DOI: 10.1079/ BJN19770102
Eger M, Riede S, Breves G, et al (2018): Induction of a transient acidosis in the rumen simulation technique. J Anim Physiol Anim Nutr, 102, 94-102. DOI: 10.1111/jpn.12662
Ellis JL, Dijkstra J, Kebreab EB, et al (2008): Aspects of rumen microbiology central to mechanistic modelling of methane production in cattle. J Agric Sci, 146, 213-233. DOI: 10.1017/S0021859608007752
Fandino JI, Calsamiglia S, Ferret A, et al (2008): Anise and capsicum as alternatives to monensin to modify rumen fermentation in beef heifers fed a high concentrate diet. Anim Feed Sci Technol, 145, 409-417. DOI: 10.1016/j.anifeedsci.2007.04.018
Fandino JI, Ferret A, Calsamiglia S (2020): Dose and combinations of anise oil and capsicum oleoresin as rumen fermentation modifiers in vitro and in vivo with high concentrate diets fed to Holstein beef heifers. Anim Feed Sci Technol, 260, 114363. DOI: 10.1016/j.anifeedsci.2019. 114363
Figueiredo AF, Brede M, Heller J, et al (2024): Anaerobic digestion of hemp and flax straw and shives and rapeseed straw by the ruminal microbiota. Bioenergy Res, 17, 700-709. DOI: 10.1007/s12155-023-10667-7
Foggi G, Terranova M, Daghio M, et al (2024): Evaluation of ruminal methane and ammonia formation and microbiota composition as affected by supplements based on mixtures of tannins and essential oils using Rusitec. J Anim Sci Biotechnol, 15, 48. DOI: 10.1186/s40104-024-01005-8
Gakhar N (2008): Development of Alternate Markers of Subacute Ruminal Acidosis (SARA). Master’s thesis, in English. The University of Manitoba. Winnipeg, Manitoba.
Guo T, Guo T, Guo L, et al (2022): Rumen Bacteria Abundance and Fermentation Profile during Subacute Ruminal Acidosis and Its Modulation by Aspergillus oryzae Culture in RUSITEC System. Fermentation, 8, 329. DOI: 10.3390/fermentation8070329
Hook SE, Steele MA, Northwood KS, et al (2011): Impact of high-concentrate feeding and low ruminal pH on methanogens and protozoa in the rumen of dairy cows. Microbial Ecology, 62, 94-105. DOI: 10.1007/s00248-011-9881-0
Husz TC, Smith WN, Lockard CG, et al (2021). Comparison of monensin sodium sources for finishing beef cattle. Transl Anim Sci, 5, txab090. DOI: 10.1093/tas/ txab090
Joch M, Mrázek J, Skřivanová E, et al (2018): Effects of pure plant secondary metabolites on methane production, rumen fermentation and rumen bacteria populations in vitro. J Anim Physiol Anim Nutr, 102, 869-881. DOI: 10.1111/jpn.12910
Johnson RR (1976): Influence of carbohydrate solubility on non-protein nitrogen utilization in the ruminant. J Anim Sci, 43, 184-191. DOI: 10.2527/jas1976.431184x
Kosuge S, Furuta M (1970): Studies on the pungent principles of capsicum. Part XIV. chemical constitution of the pungent principle. J Agr. Biol. Chem, 34, 248-256. DOI: 10.1271/bbb1961.34.248
Kuenzle CC, Jenny E (1979): Biochemistry of microbial digestion in the preventriculus of ruminants. Schweiz Arch Tierheilkd, 121, 503-519.
Lana RP, Russell JB, Van-Amburgh ME (1998): The role of pH in regulating ruminal methane and ammonia production. J Anim Sci 76, 2190-2196. DOI: 10.2527/1998. 7682190X
Liu L, Sun D, Mao S, et al (2019): Infusion of sodium butyrate promotes rumen papillae growth and enhances expression of genes related to rumen epithelial VFA uptake and metabolism in neonatal twin lambs. J Anim Sci, 97, 909-921. DOI: 10.1093/jas/sky459
Mahmood M, Samli HE, Sener-Aydemir A, et al (2022): Moringa oleifera and Propolis in cattle nutrition: characterization of metabolic activities in the rumen in vitro. Metabolites, 12, 1237. DOI: 10.3390/metabo12121237
Mickdam E, Khiaosa-Ard R, Metzler-Zebeli BU, et al (2016): Rumen microbial abundance and fermentation profile during severe subacute ruminal acidosis and its modulation by plant derived alkaloids in vitro. Anaerobe, 39, 4-13. DOI: 10.1016/j.anaerobe.2016.02.002
Min BR, Mcnabb WC, Barry TN, et al (2000): Solubilization and degradation of ribulose-1,5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39; Rubisco) protein from white clover (Trifolium repens) and Lotus corniculatus by rumen microorganisms and the effect of condensed tannins on these processes. J Agric Sci Cam, 134, 305-317. DOI: 10.1017/S0021859699007518
Nelson EK, Dawson LE (1923): The constitution of capsaicin, the pungent principle of Capsicum. III. J Am Chem Soc, 45, 2179-2181. DOI: 10.1021/ja01662a023
Newbold CJ, Elhassan SM, Wang J, et al (1997): Influence of foliage from african multipurpose trees on activity of rumen protozoa and bacteria. J Nutr, 78, 237- 249. DOI: 10.1079/BJN19970145
Oeztuerk H, Emre B, Sagmanligil V, et al (2010): Effects of nisin and propolis on ruminal fermentation in vitro. J Anim Vet Adv, 9, 2752-2758. DOI: 10.3923/javaa.2010. 2752.2758
OJEU (2003): Regulation (EC) No 1831/2003 of the European Parliament and the Council of 22 September 2003 on additives for use in animal nutrition. Off J Eur Union, 10/18/2003, L268/36. Available at http://data.europa.eu/eli/ reg/2003/1831/oj (Accessed July 27, 2026)
Orton T, Rohn K, Breves G, et al (2020): Alterations in fermentation parameters during and after induction of a subacute rumen acidosis in the rumen simulation technique. J Anim Physiol Anim Nutr, 104, 1678-1689. DOI: 10.1111/jpn.13385
Orzuna-Orzuna JF, Godina-Rodríguez JE, Garay-Martínez JR, et al (2024): Capsaicin as a dietary additive for dairy cows: A meta-analysis on performance, milk composition, digestibility, rumen fermentation, and serum metabolites. Animals, 14, 1075. DOI: 10.3390/ani14071075
Ozturk H (2003): In vitro studen zum einfluss von topinamburmehl und saccharomyces boulardii auf den mikrobiellen vormagenstoffwechsel. PhD thesis, in German. Hannover, Germany.
Periferakis AT, Periferakis A, Periferakis K, et al (2023): Antimicrobial properties of capsaicin: available data and future research perspectives. Nutrients, 15, 4097. DOI: 10.3390/nu15194097
Petri RM, Antlinger B, Khol LJ, et al (2025): Optimization of RUSITEC model adaptations for in vitro simulation of subacute ruminal acidosis and evaluation of Saccharomyces cerevisiae supplementation on microbial fermentation and stability. Front Anim Sci, 6, 1620969. DOI: 10.3389/fanim.2025.1620969
Ram PK, Verma SP, Agrawal AK, et al (2007): Effect of severity of acidosis on ruminal activity in goats. Indian J Anim Res, 41, 256-260.
Reyes-Escogido ML, Gonzalez-Mondragon EG, Vazquez-Tzompantzi E, et al (2011): Chemical and pharmacological aspects of capsaicin. Molecules, 16, 1253-1270. DOI: 10.3390/molecules16021253
Russell JB, Houlihan AJ (2003): Ionophore resistance of ruminal bacteria and its potential impact on human health. FEMS Microbiol Rev, 27, 65-74. DOI: 10.1016/S0168-6445(03)00019-6
Russell JB, Strobel HJ (1989): Effect of ıonophores on ruminal fermentation. Appl. Environ. Microbiol, 55, 1-6. DOI: 10.1128/AEM.55.1.1-6.1989
Schelling GT (1984): Monensin mode of action in the rumen. J Anim Sci, 58, 1518-1527. DOI: 10.2527/jas1984. 5861518x
Sharma S, Jain S, Nair GN, et al (2013): Capsicum annuum enhances L-lactate production by Lactobacillus acidophilus: implication in curd formation. J Dairy Sci, 96, 4142-4148. DOI: 10.3168/jds.2012-6243
Weiss WP (2005): Antioxidant Nutrients, Cow Health, and Milk Quality. 11-18. In: Proceedings of the Penn State Dairy Cattle Nutrition Workshop, Grantville, USA.
Wolin MJ (1960): A theoretical rumen fermentation balance. J Dairy Sci, 43, 1452-1459. DOI: 10.3168/ JDS.S0022-0302(60)90348-9
Yost WM, Young JW, Schmidt SP, et al (1977): Gluconeogenesis in ruminants: Propionic acid production from a high-grain diet fed to cattle. J Nutr, 107, 2036-2043. DOI: 10.1093/jn/107.11.2036
You W, Cheng H, Hu X, et al (2025): Capsaicin modulates ruminal fermentation and bacterial communities in beef cattle with high-grain diet-induced subacute ruminal acidosis. Microorganisms, 13, 84. DOI: 10.3390/ microorganisms13010084
Zhang Z, Wu D, Li X, et al (2025): Gastrointestinal development and tight junctions of preweaned calves supplemented with sodium butyrate in the starter mixture and whole milk. Trop Anim Health Prod, 57, 234. DOI: 10.1007/s11250-025-04464-x

Details

Primary Language

English

Subjects

Veterinary Anatomy and Physiology

Journal Section

Research Article

Authors

Melis Unler ^*
0000-0003-4113-4905
Türkiye

Hakan Öztürk
0000-0003-2913-2069
Türkiye

Early Pub Date

August 19, 2026

Publication Date

-

Submission Date

February 19, 2026

Acceptance Date

July 16, 2026

Published in Issue

Year 2026 Number: Advanced Online Publication

DOI

https://doi.org/10.33988/auvfd.1892357

IZ

https://izlik.org/JA45DB73UJ

Cite

RIS / Bibtex

APA

Unler, M., & Öztürk, H. (2026). Effects of capsaicin on rumen fermentation under normal and acidosis pH conditions: A comparative Rusitec study with monensin. Ankara Üniversitesi Veteriner Fakültesi Dergisi, Advanced Online Publication. https://doi.org/10.33988/auvfd.1892357

AMA

1.Unler M, Öztürk H. Effects of capsaicin on rumen fermentation under normal and acidosis pH conditions: A comparative Rusitec study with monensin. Ankara Univ Vet Fak Derg. 2026;(Advanced Online Publication). doi:10.33988/auvfd.1892357

Chicago

Unler, Melis, and Hakan Öztürk. 2026. “Effects of Capsaicin on Rumen Fermentation under Normal and Acidosis PH Conditions: A Comparative Rusitec Study With Monensin”. Ankara Üniversitesi Veteriner Fakültesi Dergisi, no. Advanced Online Publication. https://doi.org/10.33988/auvfd.1892357.

EndNote

Unler M, Öztürk H (August 1, 2026) Effects of capsaicin on rumen fermentation under normal and acidosis pH conditions: A comparative Rusitec study with monensin. Ankara Üniversitesi Veteriner Fakültesi Dergisi Advanced Online Publication

IEEE

[1]M. Unler and H. Öztürk, “Effects of capsaicin on rumen fermentation under normal and acidosis pH conditions: A comparative Rusitec study with monensin”, Ankara Univ Vet Fak Derg, no. Advanced Online Publication, Aug. 2026, doi: 10.33988/auvfd.1892357.

ISNAD

Unler, Melis - Öztürk, Hakan. “Effects of Capsaicin on Rumen Fermentation under Normal and Acidosis PH Conditions: A Comparative Rusitec Study With Monensin”. Ankara Üniversitesi Veteriner Fakültesi Dergisi. Advanced Online Publication (August 1, 2026). https://doi.org/10.33988/auvfd.1892357.

JAMA

1.Unler M, Öztürk H. Effects of capsaicin on rumen fermentation under normal and acidosis pH conditions: A comparative Rusitec study with monensin. Ankara Univ Vet Fak Derg. 2026. doi:10.33988/auvfd.1892357.

MLA

Unler, Melis, and Hakan Öztürk. “Effects of Capsaicin on Rumen Fermentation under Normal and Acidosis PH Conditions: A Comparative Rusitec Study With Monensin”. Ankara Üniversitesi Veteriner Fakültesi Dergisi, no. Advanced Online Publication, Aug. 2026, doi:10.33988/auvfd.1892357.

Vancouver

1.Melis Unler, Hakan Öztürk. Effects of capsaicin on rumen fermentation under normal and acidosis pH conditions: A comparative Rusitec study with monensin. Ankara Univ Vet Fak Derg. 2026 Aug. 1;(Advanced Online Publication). doi:10.33988/auvfd.1892357