Introduction
Allium ursinum L. (Allioideae Herbert), also known as wild garlic or bear garlic, is a plant growing in the middle
and eastern regions of Europe. It is regularly applied as an ingredient of local cuisine
and herbal medicine [1], [2]. The plant grows in mountain and forestall areas with fertile soil and high moisture,
especially ravine, alder gallery and oak-hornbeam forests [3], [4], [5]. However, it may also be cultivated in regular agrarian conditions in ultra-high-fertile
soil of cernozem or in co-cultivation of horseradish (Armoracia rusticana G. Gaertn.) [6], [7].
The edible part is the lancet leaves of the plant, which are carriers of numerous
antioxidant, antimicrobial, and anti-inflammatory agents. Wild garlic grows actively
starting in February, and its vegetation lasts until June. The three-limbed stem of
the plant may grow up to 40 cm, and two or three elliptical leaves surround it. At
the top of the stem, white flowers flourish between April and May [7]. The leaves are usually collected in this period. Then, they are dried or macerated
in alcohol to prepare local food products, such as rennet cheeses, fermented milk
products, and tinctures [8], [9], [10].
This aims to discuss the current proceedings on bioactive compounds of Allium ursinum and the biological effects observed for them individually and the synergistic effect
of the whole plant. To prepare this paper, we browsed papers published mostly since
2005 involving the following key words: “Allium ursinum”, “ransom”, “wild garlic”, “anti-inflammatory”, “anti-oxidant”, “allicin”, and “anti-microbial
activity”. We browsed the Google Scholar, PubMed, and Scopus databases.
Searching methods
References were sought using Publish or Perish software. We browsed the PubMed, Cross
Reference, and Google Scholar bases. Most of the literature search was based on papers
published from 2015 to 2024 and included at least one of the following keywords: “Allium
ursinum”, “ramson”, or “wild garlic”, as well as one of the following “antioxidant
potential”, “anti-inflammatory”, “chemical composition”, “bactericidal effect”, and
“anti-tumor effect”. Then, the list of papers was enriched with other papers published
between 2005 and 2024 supporting the claims from the prior literature search.
Chemical Composition of Allium ursinum
Phenolics
Wild garlic as a leafy vegetable has relevant amounts of phenolic compounds including
phenolic acids and flavonols. Total phenolic content in methanolic extracts is up
to 33.29 ± 0.29 mg gallic acid equivalents/g dry matter (d. m.) and is associated
with antioxidant activity [11], [12]. Thereby, depending on the harvest period in March compared to in May, total phenolic
content [38 – 47 mg of gallic acid equivalents/100 g of fresh matter (f. m.)] and
antioxidant activity increase [13].
First of all, it should be noted that wild garlic is poor in phenolic acids when compared
with other medicinal plants (free phenolic acids: 3.24 ± 0.29 mg/g d. m., bound phenolic
acids: 1.10 ± 0.17 mg/g d. m.). Among the free phenolic acids, mainly ferulic acid
and vanillic acid were observed ([Fig. 1]) and additionally, among the bound ones, p-coumaric acid [11], [14], [15], [16].
Fig. 1 The predominant phenolic compounds present in Allium ursinum. Wild garlic painting authored by Carl Axel Magnus Lindman.
Kaempferol glycosides are the main compounds in wild garlic leaves with up to 253 mg/100 g
f. m. [11], [15], [16]. Based on mass spectrometric studies, a few main compounds could be tentatively
identified. These are kaempferol-3-neohesperidoside-7-glucoside, kaempferol-3-neohesperidoside-7-coumaroyl-diglucoside,
kaempferol-3-neohesperidoside, kaempferol-3-neohesperidoside-7-coumaroyl-glucoside,
and the acetylated forms thereof [17], [18]. The amounts of kaempferol-3-neohesperidoside-7-glucoside and kaempferol-3-neohesperidoside-7-coumaroyl-diglucoside
were observed at ca. 2 mg/g d. m. each. Among flavonols, NMR studies have identified
the following compounds: kampferol-3-neohesperidoside-7-coumaroyl-glucoside, kaempferol-3-neohesperidoside-7-coumaroyl-glucoside
dodeca acetate, kaempferol-3-neohesperidoside-7-feruloyl-glucoside,
kaempferol-3-neohesperidoside-7-coumaroyl-glucoside dodeca acetate, kaempferol-3-neohesperidoside-7-coumaroyl-diglucoside,
and kaempferol-3-neohesperidoside-7-coumaroyl-diglucoside pentadeca acetate [19].
In wild garlic flowers, similar compounds were detected, including kaempferol-3-glucoside,
kaempferol-3-glucoside-7-glucoside, kaempferol-3-neohesperidoside, and kaempferol-3-neohesperidoside-7-glucoside
[20].
Thiopolysulfides
Like all Allium plants, wild garlic contains sulfur compounds that contribute to its characteristic
aroma. These include alliin and its degradation product–allicin, from which further
aroma components are formed: diallyl disulfide, diallyl trisulfide, 3-vinyl-(4H)-ditiin,
and 2-vinyl-(3H)-1,3 ditiin [21]. Furthermore, degradation products of S-methyl cysteine sulfoxide, namely dimethly
disulfide, dimethyl trisulfide, and dimethylthiosulfonate, also contribute to the
aroma of wild garlic. It is shown that the sulfur compounds from wild garlic are effective
against Candida spp, Aspergillus niger, Botrytis cinerea, or Pennecillium gladioli
[22], [23]. Other pathogenic microorganisms can also be reduced by wild garlic extracts [11]. Furthermore, alliin is shown to increase during plant development from 25 to 45%
of the cystein sulfoxid
pattern [24].
Compared to other Allium species, the number of thiosulfinate esters measured by HPLC and NMR is low. The
main four compounds are 2-propene-1-sulfinothioic acid S-2-propenyl ester (28%), 2-propene-1-sulfinothioic
acid S-methyl ester (16%), methanesulfinothioic acid S-(E)-propenyl ester (34%), and
methanesulfinothioic acid S-methyl ester (20%) [25].
Thereby, studies show the most quantitatively relevant volatile sulfur compounds are
methyl-2-propenyl trisulfides (14%), di-2-propenyl disulfides (25%), and di-2-propenyl
trisulfides (16.5%) [20], [26]. During plant development, methyl 2-propenyl disulfide decreases from ca. 35% to
ca. 12%, while di-2-propenyl sulfide increases from ca. 2% to ca. 5%, and di-2-propenyl
disulfide remains unchanged. Other volatile compounds remain essentially unchanged
at lower concentrations [24].
Antioxidant activity of Allium ursinum
Recent papers show that wild garlic possesses diverse antiradical capacity. However,
the results differ noticeably between the studies, which results from differences
in post-collection treatment, solvent type, and extraction time ([Table 1]). The best described is the antiradical capacity measured with the scavenging of
a 2,2-diphenyl-1-picrylhydrazyl radical (DPPH· test). Nonetheless, the activity of the plant against this compound is rather moderate.
Scavenging of 50% of present radicals (SC50) ranges from 154 to 1400 µg in aqueous leaf extracts, while in the methanolic and
ethanolic extracts, it is roughly 111 µg and 1100 µg, respectively [11], [27], [28]. Meanwhile, for butyryl hydroxytoluene and butyryl hydroxyanisole SC50 was 2.82 µg/mL and 2.44 µg/mL, respectively [28], and for Allium
tuberosum var. Rottler ex Spreng, the half-scavenging dose equaled 97.46 µg/mL in the ethanolic
extract and 141.68 in the aqueous one [29]. The antiradical capacity of the plant results mainly from the high content of phenolics
but is not limited by the content of these secondary plant metabolites [7], [30]. The study of Nikkhani et al. [26] showed that the phenolic constituents may chelate zinc and manganese, which decreases
its antiradical capacity. The chelating ability of Mn ions was the highest in the
aqueous extract (nearly 99% yield), while for Zn, the best chelator was the ethanolic
extract (93%). Meanwhile, in the food matrix, the chelating ability of Allium ursinum remains high (over 68%), but its antiradical ability against DPPH· is very low (0.4 µmol TE/mL) [31].
Table 1 Antiradical activity of Allium ursinum leaves.
|
Extractant/Food matrix
|
ABTS+· test
|
DPPH· test
|
FRAP test
|
Reference
|
|
n/e – not examined; AA – ascorbic acid; EC50 – 50%-scavenging activity; TE – Trolox equivalent; d. m. – dry matter; f. w. – fresh
weight
|
|
Water
|
n/e
|
10.1 mM TE/g d. m.
|
42.1 mM TE/g d. m.
|
Petkova et al. [35]
|
|
n/e
|
EC50 – 471.0 µg/mL
|
n/e
|
Nikkhahi et al. [27]
|
|
n/e
|
EC50 – 154.2 µg/mL
|
n/e
|
Krivoklapic et al. [72]
|
|
n/e
|
EC50 – 1400.0 µg/mL
|
n/e
|
Pavlović et. [28]
|
|
70%-MeOH
|
n/e
|
8.3 – 16.4%
|
n/e
|
Jedrszczyk et al. [73]
|
|
80%-MeOH
|
n/e
|
35.7 – 48.0%
|
n/e
|
Kovarović et al. [30]
|
|
79.7 µmol TE/g f. w.
|
2.0 µmol TE/g f. w.
|
8.6 µmol TE/g f. w.
|
Lachowicz et al. [13]
|
|
91.7 µmol TE/g d. m.
|
n/e
|
11.7 µmol TE/g d. m.
|
Lachowicz et al. [18]
|
|
n/e
|
EC50 – 1100.0 µg/mL
|
n/e
|
Pavlović et. [28]
|
|
n/e
|
EC50 – 66.7 – 77.2 µg/mL
|
n/e
|
Pejatović et al. [37]
|
|
72.3 µmol TE/g d. m.
|
2.5 µmol TE/g d. m.
|
n/e
|
Škrovánková et al. [34]
|
|
MeOH
|
n/e
|
raw material – 88.4%; dried material – 40.7 – 53.3%
|
n/e
|
Lukinac and Jukić [32]
|
|
n/e
|
EC50 – 111.0 µg/mL
|
n/e
|
Krivoklapic et al. [72]
|
|
n/e
|
EC50 – 630.0 µg/mL
|
n/e
|
Pavlović et. [28]
|
|
70%-EtOH
|
n/e
|
EC50 – 46.1 – 77.2 µg/mL
|
n/e
|
Pejatović et al. [37]
|
|
n/e
|
EC50 – 1030.0 µg/mL
|
n/e
|
Pavlović et al. [28]
|
|
n/e
|
EC50 – 532.0 µg/mL
|
n/e
|
Nikkhahi et al. [27]
|
|
80%-EtOH
|
1.7 – 2.2 µmol TE/mL
|
n/e
|
n/e
|
Voća et al. [12]
|
|
n/e
|
45.3%
|
n/e
|
Lenková et al. [74]
|
|
96%EtOH
|
n/e
|
EC50 – 850.0 µg/mL
|
n/e
|
Pavlović et al. [28]
|
|
n/e
|
EC50 – 4,936.6 µg/mL
|
14.5%
|
Jovanova et al. [41]
|
|
EtOH
|
n/e
|
EC50 – 643.0 µg/mL
|
n/e
|
Nikkhahi et al. [27]
|
|
80%-Acetone
|
n/e
|
22.0 – 27.9%
|
0.6 – 0.9 mg AA/g f. w.
|
Gordanić et al. [7]
|
|
Chloroform
|
n/e
|
EC50 – 391.8 µg/mL
|
n/e
|
Krivoklapic et al. [72]
|
|
Corn snacks
|
n/e
|
19.2 – 87.7%
|
n/e
|
Kasprzak-Drozd et al. [47]
|
|
Meat and potato-based infant formula
|
n/e
|
0.4 µmol TE/mL
|
n/e
|
Stanislavljević et al. [31]
|
|
Tincture
|
n/e
|
SC50 – 45.0 – 50.0 µg/mL
|
n/e
|
Pejatović et al. [37]
|
The high deviation in antiradical capacity between the referred studies may originate
from different soil conditions during the plant cultivation. Gordanić et al. [7] compared Allium ursinum cultivated in different soils. Their study showed that Fluvisol and Chernozem positively
affected the scavenging abilities against DPPH.
The drying method of the leaves may significantly change their antioxidant capacity.
In the study of Lukinac and Jukić [32], it was noted was that an air temperature of 40 °C decreased DPPH· scavenging activity by over a third, and a drying temperature of 60 °C showed the
highest efficiency in phenolic acids and flavonols amount in the final drought [33].
Conversely to DPPH·, the antiradical activities against ABTS+· are noticeably higher–almost 30-fold for 80%-methanol extracts [34]. Nonetheless, the properties against ABTS+· differed significantly between different growing locations, which showed that the
overall antiradical potential relates from the cultivation yield and cultivation conditions
[12]. What is more, the authors of the cited study [12] noted that flowering negatively affects the antiradical capacity even by half. This
information seems to be important, as the plant leaves are usually collected after
the flowering period. On the other hand, Lachowicz et al. [13] observed higher antioxidant capacity against both radicals for summer collections
than for the spring ones. However, no statistical significance was found between them.
Wild garlic leaves are also good iron (III)-reducing agents, which may be observed
in the ferric-reducing activity capacity (FRAP). The reducing ability oscillates between
8 and 12 µmol TE/g d. m. ([Table 1]). In contrast, Petkova et al. [35] observed significantly higher values for aqueous extract–over 42 mmol TE/g d. m.
Except for the different extractants used, the last study involved high temperature
of the extraction process and remaceration of the raw material, which could result
in a higher yield of the process. The analogical tendency was observed in the super-critical
extraction of wild garlic leaves by Tomšik et al. [36], who observed higher ABTS+· activity along with rising process temperature. However, for DPPH· ability, they noted an opposite relation. This conclusion may be supported by Pejatović
et al. [37], who showed that
long-time extraction in ambient temperature effects in the lowest doses of extract
needed to halve DPPH· activity (EC50 values). On the other hand, da Silva Araujo et al. [38] showed that the temperature effect on the activity against DPPH· is not as significant as the ethanol concentration in the extractant and the opposite
tendency for the activity measured in FRAP test. This stands in line with proceedings
on DPPH· activity measured in ethanolic extracts, in which EC50 values declined with the growing concentration of ethanol in the extractant ([Table 1]).
According to Gordanić et al. [7], iron-reducing ability also depends on soil fertility, with the highest activity
noted for cultivars grown in chernozem and the lowest for arenosol-grown. The authors
of the cited study noted that FRAP values range between 3.5 and 4.9 µmol ascorbic
acid (AA) per gram of fresh leaves [7], which follows the previous observation, in which ascorbic acid in the FRAP assay
generates a stronger positive response than other standards [39]. The values by are nearly 30- to 40-fold lower than for flowers of Allium cepa and 10- to 13-fold lower than flowers of Cucurbita maxima
[40]. Nonetheless, the reductive effect of A. ursinum may be comparable with 250 µg AA and stronger than for A. schoenoprasum L., a plant commonly used in meal preparations [41].
CUPRAC (cupric-ion-reducing antioxidant ability) is a test applied instead of FRAP
to illustrate the reducing potential of the tested analyte against the heavy metals.
For wild garlic leaves, the Cu2+-reducing ability oscillates between 6.2 and 15.3 µmol AA/g [7].
The high capacity measured with this ABTS+·-scavenging test (TEAC) relates to high chlorophyll and carotenoids content, especially
neoxanthin, lutein, and α- and β-carothene [18]. The authors observed that carotenoids are responsible for ferric ion reduction
in a FRAP test, as well. Comparable ability to scavenge ABTS+· and Fe3+ was noted for xanthophylls, especially for violaxanthin, neoxanthin, and lutein,
in another study [42]. However, Lachowicz et al. [18] observed a stronger relation between the xanthophylls and the ABTS+· test than the FRAP test, but for violaxanthin, the statistical effect was poor for
both. The similar strong effect noted for the FRAP and ABTS+· results from the similar mechanism of single-electron transfer between the reagent
and the active compound. Carotenoids, due to the presence of cyclic
ligands and conjugated bonds, may delocalize electron deficiency [43]. Meanwhile, the DPPH· scavenging ability of herbal plants originates mainly from total flavonoids, total
phenolics, and the synergistic effect of all bioactive phytocompounds present (r2 values 0.91, 0.90 and 0.96, respectively), but the effect of the carotenoids present
is also very strong (r2 = 0.87) [44]. Since a proton donation mechanism neutralizes DPPH·, the wide range of phytocompounds with unsaturated cyclic or aromatic groups with
hydrogen ligands may be effective agents [45]. For Allium species, DPPH· scavenging also relates to the high content of total phenolic content (TPC) (r2 = 0.90). However, a stronger correlation was noted between TPC and FRAP (r2 = 0.96) [41]. The high scavenging effect of the
first is based on the fact that similar compounds are responsible for the reaction
occurring in both assays, especially flavanoles [46].
Alium urisnum added to food products may enhance their antioxidant activity ([Table 1]). Kasprzak-Drozd et al. [47] analyzed the effect of wild garlic leaves on extruded corn snacks and observed positive
relation between the wild garlic addition and the time of the extrusion on the antiradical
activity against DPPH·. According to the authors, a 10-minute extrusion of snacks enriched in 4% addition
of the leaves increased the DPPH· scavenging activity from nearly 59% to over 82%.
Moreover, the snacks enriched with the leaves had higher activity after in vitro gastric and duodenal digestion by approximately 22 and 18% points, respectively.
Similar results were delivered by Stanisavljević et al. [31] in their study of A. ursinum effect on the antioxidant effect of infant food composed of turkey meat and potatoes.
They noted that the addition of the leaves could
increase the antioxidant activity against DPPH· by 84 to 137% and even raise it after the simulated digestion process by a third,
compared with the values before the digestion. These observations seem to be key in
the context of future applications of wild garlic to food products, as the first mentioned
food product in this paragraph corresponds well with similar snack products available
on the market and is usually categorized as convenient snacks for active persons and
youth. Due to the similarity of the other food product discussed to the composition
of the traditional dinner meal, the results of the Stanisavljević et al. [48] study may be applied in designing novel variants of traditional foods and meals
in countries with meat- and starch-based based cuisines, e.g., Polish, German, and
Czech dishes.
This leads to the conclusion that wild garlic may be added to numerous foods, dietary
supplements, and other products to boost their antioxidant and other functional effects.
Moreover, the literature on the subject shows that the antioxidant activity of phytocompounds
highly relates with their anti-inflammatory, inhibitory, and antimicrobial properties
[28], [31], [41], [49].
Anti-inflammatory effects of Allium ursinum L.
Garlic and the organosulfur compounds present in the immune system have a positive
effect on it ([Fig. 2]). This effect has been demonstrated in studies and is based on several main mechanisms:
on immune response, on anti-inflammatory response, and on interleukins as a response
to oxidative stress [50]. Allicin and derivatives present in garlic, at 10 µg/ml of garlic extract, inhibited
the synthesis of multiple pro-inflammatory cytokines (TNF-α, IL-12, IL-1α, and IL-1β), as well as other inflammation-related cytokines (IL-2, IL-6, IL-8, and IFN-γ) in patients with specific inflammatory bowel disease [51], [52].
Fig. 2 Allicin and its anti-inflammatory and antimicrobial effect. Wild garlic painting
authored by Carl Axel Magnus Lindman.
Toxicity of Allium ursinum L.
Wild garlic constituents have been described as anti-tumor and anti-parasite agents
([Table 2]). In the study of Krstin et at. [53], a hydrophobic extract of Allium ursinum bulbs significantly inhibited the viability of T b. brucei and Leishmania tarentolae cells, while the toxicity against the HaCaT human skin line was respectively 20-fold
and 4-fold poorer. Moreover, Xu et al. [54] also noted cytotoxic effect of Allium ursinum on a cancer cell line. In their study, an aqueous extract of wild garlic leaves significantly
increased the apoptosis of the AGS cancer cell line and almost completely cleaved
the presence of cyclin B in the cells. Cyclin B is a key marker of solid tumor progression.
Its high levels are connected with an unrestricted cell cycle and cell malignant transformation
[55]. However, the authors of the cited
AGS-based study had found no information on the potential mechanism of the anti-tumor
effect of the extract. They considered the observed effects with the presence of thiopolysulfides.
Table 2 Summary of Allium ursinum effects on different cell lines.
|
Allium ursinum extract/compound
|
Organism
|
Tissue
|
Cell line
|
Dose
|
Reference
|
|
Bulb extract in dichloromethane 3 : 10 (m/v)
|
T. b. brucei
|
N/A
|
N/A
|
IC50 1.45 µg/mL
|
Krstin et al., [53]
|
|
Leishmania tarentolae
|
N/A
|
N/A
|
IC50 5.87 µg/mL
|
|
Human
|
Skin
|
HaCaT
|
IC50 23.71 µg/mL
|
|
Leaf extract in methanol 1 : 20 (m/v)
|
Rat
|
Embryo
|
H9c2
|
50 µg/mL+ 1 µM doxo – 25% viability
|
Pop et al., [60]
|
|
Leaf extract in water 1 : 20 (m/v)
|
Rat
|
Embryo
|
H9c2
|
50 µg/mL+ 1 µM doxo – 70% viability
|
|
Leaf extract in methanol 1 : 25 (m/v) + 1% AcOH
|
Human
|
Xenograft tumor
|
AGS
|
IC50 16.2 µM
|
Xu et al., [54]
|
|
Diallyl trisulfide
|
Human
|
Lung cancer
|
H358
|
40 µM – 45% apoptosis
|
Xiao et al., [56]
|
|
H460
|
40 µM – 45% apoptosis
|
|
Bronchial epithelium
|
BEAS-2B
|
40 µM – 12% apoptosis
|
|
Human
|
Colon cancer
|
DLD-1
|
IC50 13.3 µM
|
Hosono et al. [75]
|
|
HCT-12
|
IC50 – 11.5 µM
|
|
Diallyl disulfide
|
Human
|
Neuroblastoma
|
SH-SY5Y
|
50 µM – 28% apoptosis
|
The hypothesis that the anti-tumor properties of Alii ursini folia depend on the presence of thiopolysulfides may be confirmed by numerous papers highlighting
the potential of these compounds to induce apoptosis of cancer cell lines. In the
work of Xiao et al. [56], a dose of 40 µM diallyl trisulfide halved the population of H358 and H460 (45%
apoptosis). The toxicity against these lung cancer cell lines was almost fourfold
higher than observed in the bronchide epilethium cell line of BEAS-2B exposed to the
analogical dose of the compound. The higher apoptosis ratio of the cancer lines was
related to significantly higher DNA damages observed in them [57]. The metabolism of cancer cells tends to generate ROS at higher levels than normal
cells in different biological pathways. The rapid metabolism of the tumor cells produces
a large number of ROS, i.e., superoxide (O2−), hydroxyl radical
(·OH), and hydrogen peroxide (H2O2). Moreover, carcinogenesis can also be associated with aberrations of genomic DNA
methylation, such as hypermethylation and hypomethylation of the promoter or first
exon of cancer-related genes [58]. The process of hypomethylation accelerates tumor development further by activating
the transcription of protooncogenes and proteins involved in genomic instability and
malignant cell metastasis. On the other hand, the main products of DNA methylation,
i.e., N3-methyladenine and N3-methylguanine (N3MeG), are able to trigger apoptosis by affecting the additional DNA strand breaks
[59].
Meanwhile, extracts and bioactive ingredients of wild garlic may protect non-cancer
cells against different toxic agents. In the study of Pop et al. [60], murine cardiomyoblasts of line H9c2 were exposed to doxorubicin in the presence
of A. ursinum extract constituents. The authors observed that a methanolic extract of wild garlic
had significant positive effect on cell viability but had no significant effect on
the release of reactive oxygen species from the cells and from their mitochondria.
Conversely, the aqueous extract decreased the ROS release from the cells and the mitochondria
by 40 and 25%, respectively.
Antibacterial activity of Allium ursinum
Wild garlic has a beneficial effect on skin conditions, skin inflammation, as well
as accelerating the wound healing process. Moreover, Allium ursinum has been proven to have antimicrobial activity against certain bacteria, both Gram-positive
and Gram-negative ([Fig. 2]). This interaction is mainly related to alliin and other thiosulfates, as well as
to their products (diallyl thiosulfinate, methyl and diallyl sulfides, et al.) showing
antimicrobial activity. Alliinases catalyze the conversion of odorless cysteine sulfoxides
to volatile thiosulfates [61], [62].
Allicin alone at a dose of 4.2 mg/day compared to ascorbic acid and β-carotene contributed to complete eradication of Helicobacter pylori, also compared to other treatments for this infection in patients [63]. Moreover, analyses of the anti-inflammatory activity for compounds present in garlic
were also conducted for the treatment of hernia in an in vivo model in rabbits [64]. It was shown that the inclusion of allicin (900 µg/ml) into a chlorhexidine digluconate
solution (concentration 0.05%) in the polypropylene mesh resulted in antimicrobial
activity against gastrointestinal bacteria Sa ATCC25923, and therefore, it can be
successfully used in prophylactic to resist infection during such treatment. The essential
component for such antimicrobial effects was allicin.
The antibacterial effect of allicin has been found against Staphylococcus epidermidis. In the case of joint prosthetics, biofilm infection can result in severe health
consequences, as antibiotic resistance in biofilm is up to 1000 times higher. A study
by Zhai et al. [65] showed that allicin (4 mg/l) strongly enhanced the antimicrobial properties of vancomycin
(20 mcg/mL), compared to their separate use (vancomycin: 4.75 log10 CFU/mL and allicin 3.56 log10 CFU/mL), resulting in inhibition of S. epidermidis biofilm formation on the prosthetic surface of rabbits suffering from prosthetic
joint infections to a level of 1.71 log10 CFU/mL. In a study on 60 adult male Sprague–Dawley rats, garlic-derived compounds
showed synergistic effects with ciprofloxacin (a bactericidal drug for urinary tract
infections) in inhibiting the growth of Escherichia coli Z17 [66].
The broad spectrum of antimicrobial activity is largely dependent on sulfhydryl compounds
such as cysteine. Ajoene, as an unsaturated disulfide, has inhibitory properties (reduction
by cysteine abolishes antimicrobial activity), especially against Gram-positive bacteria
and yeast [67].
Also, in relation to Candida albicans fungal infections, the value of allicin use in terms of animal survival was found.
In a mouse model of systemic candidiasis, the efficacy of allicin was verified in
comparison to the antifungal fluconazole (resistance to this agent is steadily increasing),
and allicin (5 mg/kg per day) was shown to be less effective than fluconazole while
increasing mean survival time by up to twofold [68]. Against Trichophyton rubrum, allicin from garlic has also been identified as an important biological tool for
dermatophytosis, based on results obtained by scanning electron microscopy (SEM) and
transmission electron microscopy (TEM) [69].
On the other hand, with regard to skin problems, in mice with Leishmania major, the application of 50 µM of allicin cream promoted the reduction in inflammatory
cells and the protection of the epidermis, significantly contributing to the healing
of the animals [70].
Given that the antiradical activity exhibited by the raw materials is reflected in
the anti-inflammatory activity, it is also worth noting the volatile oils found in
A. ursinum.
In food production, garlic ingredients are also used in a preservative context due
to their antimicrobial activity. Modified atmosphere packaging, which is gaining popularity,
allows food preservation and reduction in heat treatments while increasing the safety
of such food products. Researchers Cosmai et al. [71], by adding garlic extract (0.1%) to olive paste packaged with MAP1 (75% Ar, 23%
CO2, and 2% H2), showed that this significantly increased the antimicrobial inhibition and shelf
life of this product by an additional 14 days. The component responsible for this
effect was identified to be allicin from garlic [71].
