Content uploaded by İlker Türkay
Author content
All content in this area was uploaded by İlker Türkay on Dec 19, 2021
Content may be subject to copyright.
467
Addition of Vermicompost to Soil Influences Total Phenolic Content of Sweet Basil
1, Lokman ÖZTÜRK2
Abstract
Sweet basil (Ocimum basilicum L.), a medicinal and aromatic plant possesing rich phenolic and terpenoid
content, is commonly utilized for culinary and medicinal purposes around the world sinceancient times.
Vermicompost (VC) products were categorized as biostimulants along with the humic exracts andare utilized
for organic fertilizer as well asconsidered as an organic soil amendment material.Use oforganic fertilizers
preserves the essential oil yield and natural aroma of basil. In present study, the effect of increasing doses of
vermicompost additions (0%, 10%, 20%, 30%, and 40%) on total phenolic content (TPC) inthe leaves of sweet
basil were investigated. The highest TPC was determined at 10% VC applicated group as 90,02 mg/g leaf and
the lowest TPC was determined at 30% VC applicated group as 50,72 mg/g leaf in dry weight expressed as
gallic acid equivalents (GAE). Plant biostimulants are de novo products and have proved efficiency in
medicinal and aromatic plant cultivation due to their possible inducing activities on the synthesis of secondary
metabolites.
Keywords: Basil, Phenolic, Vermicompost,
1. Introduction
Naturalcompounds from Sweet Basil (Ocimum basilicum L.), a well-known member ofthe Lamiaceae family,
have been utilized toflavor foods, in oral care productsand as an ornamental herb as well (Simon et al., 1984;
Morales and Simon, 1996). Phenolic acid and other aromatic compounds impart basil withantioxidant,
antimicrobial and antitumor activities (Gutierrez et al., 2008; Hussain et al., 2008).The application
ofvermicompost or theother biofertilizers seems to reduce the use of chemical fertilizers and their adverse
effects andhence they may play an important role toobtain the purposes of sustainable agriculture(Shokooh et
al., 2013).
Organic fertilizer application on basil cultivation preserves the natural aroma and increases the essential oil
yield (Hiltunen and Holm,1999).Vermicompost products were categorized as organic fertilizers by du Jardin
(2015) in a regulatory study which was supported and then adopted by relevant EU Commissions. Plant
biostimulants are de novo products and have proved efficiency in medicinal and aromatic plant cultivation due
to their possible inducing activities on the synthesis of secondary metabolites(Raffieet al., 2016).
The aim of this study was to investigate the effects of solid vermicompost applicationon TPC of basil leaves.
Thus, an important contribution to very limited knowledge and prospective researches about the use of organic
fertilizers on medicinal and aromatic plant cultivation were aimed as well.
1
2
468
2. Methodology
seeds per 50 cc containers in a greenhousein October. At the 3rd week of the germination, one individual in
each container was selected andthe others were eliminated. The application groups were consisted of 10 basil
individuals.Vermicompost applications were carried out by mixing solid vermicompost with soil for the rates
of 0%, 10%, 20%, 30%, and 40% to bring final volume of each container to 50 cc.
Figure 1.A view of basils at the 3rd week of development.
Upper leaves at similar positions of each individual basil plant were harvested as 15 g, dried at shadow and
room temperature, and then subjected to total phenolic content analysis. Total phenolic concentration of the
extracts was determined spectrophotometrically according to the Folin-Ciocalteu method (Singleton et al.
-Range Test at P<0,05.
Statistical analysis was performed with SPSS statistic software package (1999).
Figure 2.View of basils at the greenhouse
3. Results and Conclusion
3.1 Results
It was determined that the vermicompost addition to soil increased TPC 19% at 10% application group
whereascaused a decrease in 33% TPC at 30% application group (Figure 3).
469
Figure 3. The effects of vermicompost solid applications on total phenolic content of basil.
The results from the rest of the groups,20% and 40%, were not statistically significant in terms of TPC when
compared with control group.
3.2 Conclusion
The existence of humic acid in the content of vermicompost, along with the plant growth hormones auxin and
cytokineand their related compounds, were reported as having positive effects on plant growth and
development (Scaglia et al., 2016). The results of a recent study (Türkay et al., 2018) which was carried out
with solid vermicompost application to the root zone of basil individuals with increasing doses up to 24%,
were similar and in concordance with the results of present study (Figure 4).
Figure 4. The effects of vermicompost solid applications on total phenolic content of basil (Türkay et al.,
2018).
470
The results of present study and the study carried out by Türkay et al. (2018) were demonstratedtogether in
Figure 5with the aim ofevaluate the effects of vermicompost addition on TPC in basil leavesprecisely.
Figure 5. Comparison of the results of two independent studies aimed to determine the effects of various
vermicompost solid application doses on total phenolic content of basil.
According to the results of present study, 10% solid vermicompost addition to soil caused an increase in TPC
as 90,03 mg/g leaf and the change was 19% compared to control. This value was consistent withthe results of
8% and 12% vermicompost applications in the studypreviously reported by Türkay et al. (2018). The entire
results obtained from present study were substantially in accordance with those relevant results, except a
remarkable increase in TPC at the dose of 24% vermicompost application. Vermicomposts acquire very high
microbial population as well as having humic acid and plant growth hormones such as auxin and cytokine and
their related compounds (Edwards et al., 2011). Besides, it is well known that plant phenolics are defense
compounds being incrementally synthesized as a response to the environmental stress conditions both abiotic
and biotic(Öztürk & Demir, 2002). The increase in TPC at 24% solid vermicompost application, conceivably
was correlated with the higher microbial activity at the root zone of basil individuals.
In present study 30% vermicompost addition to soil in resulted with the lowest TPC amount in the basil
leaves.Main classes of secondary metabolites,including plant phenolics,are derived from primary
metabolites.Therefore, increasing doses of vermicompost application above 24% to the root zone presumably
have negative effects on the synthesis of precursor metabolites of phenolic compounds. Although, there was
some increase in TPC at the dose of 40% compared to 30% vermicompost application, the higher
vermicompost existence above 24% at the root zone of basil individuals caused presumable adverse
interactions among the factors of soil.
Vermicomposts and derivated products are novel in agronomy and further research is needed for thoroughly
evaluate its effectiveness on medicinal and aromatic plant cultivation.
471
4. References
Shokooh, Rahimi & Mr, Dehghani-Meshkani & Naghdi Badi, Hassanali & Mehrafarin, Ali & Khalighi,
Farahnaz. (2013). Changes in Essential Oil Composition and Leaf traits of Basil (Ocimum basilicum
L.) Affected by Bio-stimulators / fertilizers Application. Journal of Medicinal Plants. 12. 83-92.
Gutierrez, B., Ryan, C., Bourke, P., 2008. The antimicrobial efficacy of plant essentialoil combinations and
interactions with food ingredients. Int. J. Food Microbiol.124, 91 97.
Hussain, A.I., Anwar, F., Sherazi, S.T.H., Przybylski, R. (2008). Chemical composition:antioxidant and
antimicrobial activities of basil (Ocimum basilicum) essentialoils depend on seasonal variations. Food
Chem. 108, 986 995.
du Jardin, P. (2015). Plant biostimulants: Definition, concept, main categories and regulation.Scientia
Horticulturae, 196, 3-14. doi:10.1016/j.scienta.2015.09.021
Rafiee, H., Naghdi Badi, H., Mehrafarin, A., Qaderi, A., Zarinpanjeh, N., Sekara, A., & Zand, E. (2016).
Application of plant biostimulants as new approach to improve the biological responses of medicinal
plants- A critical review.Journal of Medicinal Plants, 3(59), 6-39.
Öztürk, L., & Demir, Y. (2002). In vivo and in vitro protective role of proline. Plant Growth Regulation, 38(3),
259-264.
Singleton, V.L., Orthofer, R., Lamuela-Raventos, R.M. (1999). Analysis of total phenols and other oxidation
substrates and antioxidants by means of Folin-Ciocalteu reagent.Methods in Enzymology. 299: 152-
178. doi: 10.1016/S0076-6879(99)99017-1
Scaglia, B., Nunes, R. R., Rezende, M. O. O., Tambone, F., & Adani, F., 2016. Investigating organic molecules
responsible of auxin-like activity of humic acid fraction extracted from vermicompost.Sci Total
Environ, 562, 289-295. doi:10.1016/j.scitotenv.2016.03.212
R. Hiltunen and Y. Holm (Eds.). (1999). Basil, The genus Ocimum, Harwood Academic Publishers, 182 pp.,
ISBN 90-5702-432-2, Amsterdam.
Edwards, C.A., Arancon, N., Sherman, R. (2011). Vermiculture Technology, Earthworms, Organic Wastes,
and Environmental Management. CRC Press Taylor & Francis Group. 578 pp., ISBN 978-1-4398-
0987-7,Boca Raton, FL, USA.
Simon JE, Chadwick AF and Craker E (1984). Thescientific literature on Selected Herbs and Aromaticand
Medicinal plants of the Temperate zone. Herbs: An indexed Bibliography 1971-1980, Chapters I & II.
ArchonBooks: Hamden CT, p.112
Morales, M.R. and J.E. Simon (1996). New basil selections with compact inflorescences for the ornamental
market. p. 543-546. In: J. Janick (ed.), Progress in new crops. ASHS Press, Arlington, VA.
Applications on Total Phenolic Content and Some Phenological Parameters Of Sweet Basil (Ocimum
basilicum L.). In: Proceedings of the International Congress on Agriculture and Animal Sciences, 7-9
Nov, Alanya, pp. 709-716.
SPSS (1999). SPSS for Windows, Release 10.0.1. SPSS, Chicago, IL, USA.
