Table 1.

Antimicrobial activity of α-pinene and β-pinene.

S. No.	Source/Species	Model	Plant Portion	Method	Result	Ref
α-pinene
1	Sigma Aldrich	Campylobacter jejuni	-	Broth microdilution and ethidium bromide deposition	Modulation of antibiotic resistance, by reducing MIC value of ciprofloxacin, erythromycin, and triclosan, up to 512 times. α-pinene also affected antimicrobial efflux systems	[21]
2	-	Nocardia sp. Strain (P18.3), Pseudomonas putida PX1 (NCIB 10684), Pseudomonas sp. strain PIN18 (NCIB 10687), and P. fluorescens NCIB 11671	-	Strains were cultured into agar slants with α-pinene (3 g/L in media), and strains growth was recorded	Nocardia sp. growth (P18.3) was not remarkable; Pseudomonas strains (NCIB 10684, 10687, and 11,671 and PL) increased promptly when α-pinene (0.3%, v/v) was added	[22]
24	Citrus species	Propionibacterium acnes, Staphylococcus epidermidis	Peel EO	EO was isolated by hydrodistillation	EO demonstrated outstanding antibacterial properties against P. acnes and S. epidermidis	[55]
26	Sigma-Aldrich	Escherichia coli, Micrococcus luteus, Staphylococcus aureus, and Candida albicans	-	Bioautographic method MIC was measured	(+)-α-pinene exhibited modest activity. (−)-α-pinene was unable to display any activity. α-pinene and β-lactams revealed the highest effects. Although (−)-α-pinene revealed no positive activity, the derivatives like β-lactam, amino ester, and amino alcohol exhibited antimicrobial effects	[56]
28	Bursera morelensis	Candida albicans strains (ATCC 14065, ATCC 32354, donated strain, and CDBB-L-1003)	Stems (EO)	EO was extracted by hydrodistillation, and GC-MS was used to isolate compounds Disc diffusion and survival curve assay were used	Maximum antifungal activity was attributed to the EO and its constituent, namely, α-pinene. Minimum fungicidal concentration of EO was found to be 2 mg/mL. A slight reduction in C. albicans population was recorded after 12 h	[58]
30	-	Staphylococcus aureus and Escherichia coli	-	Disc diffusion test, broth microdilution, and bacterial death kinetics	Inhibition halos of 11 and 12 mm for gram-positive and -negative strains were obtained at 160 µL/mL, respectively. At 1.25 and 2.5 µL/mL, (+)-α-pinene was able to eliminate bacterial colonies formation at one time of exposure of 2 h for E. coli strain	[60]
31	Syzygium cumini	Swiss mice	Leaves (EO)	MTT assay Cytotoxic effect on macrophages was determined; cells were exposed to α-pinene and tested against Leishmania	Cytotoxic effect of α-pinene against promastigotes of Leishmania amazonensis was observed with different cell death percentages (93.7, 83.2, and 58.4%) at different concentrations (100, 50, and 25 mg/mL respectively)	[61]
40	-	House fly (Musca domestica)	-	Y-tube and house flies were selected for this test	Solution with lowest concentration did not show significant differences in Y-tube arm choice. (1S)-(-)-α-pinene had maximum repellent efficiency for house flies when compared to (1R)-(+)-α-pinene	[84]
45	Plectranthus barbatus	Malaria (Anophel es subpictus), dengue (Aedes albopictus), and Japanese encephalitis (Culex tritaeniorhynchus) mosquito vectors	EO (leaves)	GC and GC--MS were performed; larvicidal activity of EO (40, 80, 120, 160, and 200 µg/mL) and its constituents eugenol, α-pinene, and β-caryophyllene (12–100 µg/mL each) were determined by WHO methods. Mortality of larvae was measured at 24 h after exposure	EO showed substantial larvicidal effects with LC50 values of 84.20, 87.25, and 94.34 µg/mL for the selected mosquito species. For Anapheles subpictus, eugenol, α-pinene, and β-caryophyllene revealed larvicidal effects (LC50 = 25.45, 32.09, and 41.66 μg/mL), followed by Aedes albopictus (LC50 = 28.14, 34.09, and 44.77 μg/mL) and Culex tritaenior hynchus (LC50 = 30.80, 36.75, and 48.17 μg/mL, respectively)	[83]
β-pinene derivatives
27	-	Klebsiella pneumoniae, Enterobacter aerogenes, S. aureus, S. epidermidis, and Candida albicans	-	25 3-cyanopyridine compounds of β-pinene were prepared; MIC value was recorded using serial two-fold dilution method	MICs values of all derivatives ranged from 15.6 to 125 mg/l	[57]
29	-	Candida spp.	-	MIC and MFC values and microbial death curve after treatment with (+)-β-pinene enantiomers	MIC values ranged from <56.25–1800 µmol/L (+)-β-pinene. After ergosterol addition, MIC value of (+)-β-pinene was not altered, but was altered with sorbitol addition. (+)-β-pinene displayed anti-biofilm activity against multiple Candida species	[59]
α- and β-pinene
22	Dep. Pharmaceutical Sciences, Ponta Grossa, Brazil	Gram-positive bacteria (Staphylococcus aureus, S. epidermidis, S. pneumoniae, and S. pyogenes)	-	MIC value, viable cells count	All studied bacterial strains were sensitive to α- and β-pinene. MIC values ranged from 5 (α-pinene x S. epidermidis SSI 1; ATCC 12228; S. pyogenes ATCC 19,615; and S. pneumoniae) to 40 μL/mL (β-pinene x S. epidermidis ATCC 12228). Few bacterial strains were resistant antibiotics, mainly gentamicin. S. aureus was resistant to α- and β-pinene	[53]
23	Sigma-Aldrich	Antimicrobial: Escherichia coli (ATCC 11775, Staphylococcus aureus (ATCC 25923), Bacillus cereus (ATCC 11778), and Candida albicans (ATCC 10231). Antimalarial: Plasmodium falciparum (FCR-3)	-	Disc diffusion method. MIC was investigated. Antimalarial properties were analyzed using the tritiated hypoxanthine incorporation assay	(+)-β-pinene was approximately two to 12 times more effective as compared to (+)-α-pinene against both gram-positive and negative bacteria, as well as C. albicans. (+)-α-pinene shows 250-fold more antimalarial activity than (+)-β-pinene	[54]
25	Sigma-Aldrich	Candida albicans, Cryptococcus neoformans, Rhizopus oryzae, and methicillin-resistant Staphylococcus aureus (MRSA)	-	Two-fold serial dilution method was used to evaluate MIC for all the strains	MIC values of α- and β-pinene enantiomers were found to be from 117 to 6250 µg/mL. C. albicans exhibited higher sensitivity to α- and β-pinene enantiomers than MRSA. Positive enantiomers possess capability to kill 100% of C. albicans in 60 min., and 6 h was required for total killing of MRSA	[5]