A quantitative assessment of the antimicrobial activity of garlic (Allium sativum)

Potential Effects of Garlic (Allium sativum L.) on the Performance, Immunity, Gut Health, Anti-Oxidant Status, Blood Parameters, and Intestinal Microbiota of Poultry: An Updated Comprehensive Review

The use of antibiotics as growth promoters or for the prevention of some poultry diseases has faced global concern and serious criticism. Their addition to poultry feed has shown hazardous effects, including the development of antimicrobial resistance and a potentially harmful effect on human health. To eliminate these threats, there is increasing interest in natural alternatives. Plant derivatives such as garlic (Allium sativum L.) and its derivatives are presently extensively used in the poultry production system. The dietary supplementation of broilers and layers with garlic induced improvement in the production parameters, carcass quality, and intestinal integrity. The modulation of the immune response against some important viral diseases has resulted from the supplementation of poultry with garlic. Moreover, garlic has been shown to modulate gut health through antibacterial and antiparasitic activities. Treatment with garlic can also mitigate oxidative stress and reduce free-radical production. The reduction of cholesterol levels and improvement of some liver and blood parameters were also reported following the dietary inoculation of garlic. This review was designed to investigate the influence of garlic as a dietary additive on the performance, immunity, gut health, anti-oxidant status, blood parameters, and intestinal microbiota of poultry.

Integration assay of bacteriological risks in marine environment using salmonella spp and multimarker response in the bivalve Donax trunculus: Novel biomonitoring approach

Microbiological contamination is one of the riskiest forms of human contamination in seawater, which threaten the stability of ecosystems and human health. In this study, we study the accumulation of a pathogenic bacteria Salmonella spp; isolated from the marine environment, in the soft tissue of Donax trunculus (Mollusca, Bivalvia), a commonly used as a bioindicators species for aquatic ecosystems monitoring, under laboratory conditions during both exposure and recovery periods. These bacteria were added in seawater at three concentrations previously determined against sentinel specie at three exposure periods (24, 48 and 96 h). In a second series of experiments, exposed specimens were afterward transplanted to clean water to assess the recovery pattern. The mortality rate of bivalves was determined as biomarker of general stress. Our findings suggest that microbiological contamination by Salmonella spp was gradually incorporated into the body of D. trunculus causing a significant induction of enzymatic activity of acetylcholinesterase (AChE), Catalase (CAT), glutathione-S-transferase (GST) and malondialdehyde (MDA) levels, as a function of time and concentration. Exposure to a bacterial concentration of 5.10⁴ bacteria/liter resulted in the mortality of more than 80% of the specimens. This study is to test the pathogenicity of Salmonella strains at concentrations close to those of the marine environment, and their effects on biomarkers, thus deducing the existence of an exponential relationship between bacterial concentrations and enzymatic response. The principal component analysis shows that the four biomarkers had similar variation with bacterial concentrations, while two groups were obtained to change following the exposure time (CAT-GST and AChE-MDA). This study provides new findings on the potential accumulation of pathogenic bacteria associated with neurotoxicity and oxidative stress in the wedge clam Donax trunculus.

Antibacterial Activity of Nanoparticles of Garlic (Allium sativum) Extract against Different Bacteria Such as Streptococcus mutans and Poryphormonas gingivalis

To combat the threat of antimicrobial resistance, it is important to discover innovative and effective alternative antibacterial agents. Garlic has been recommended as a medicinal plant with antibacterial qualities. Hence, we conducted this study to evaluate the antibacterial activity of ultrasonicated garlic extract against Escherichia coli, Staphylococcus aureus sub. aureus, Streptococcus mutans, and Poryphyromonas gingivalis. Aqueous ultrasonicated garlic extract was tested against these strains, and their antibacterial activity quantified using both agar disk diffusion and agar well diffusion methods; the plate count technique was used to estimate the total viable count. Moreover, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and microplate spectrophotometry were used to characterize garlic nanoparticles. The results confirmed that all tested bacteria were sensitive to both sonicated and non-sonicated garlic extracts. Streptococcus mutans was the most susceptible bacteria; on the other hand, Escherichia coli was the most resistant bacteria. Furthermore, characterization of the prepared garlic nanoparticles, showed the presence of organosulfur and phenolic compounds, carboxyl groups, and protein particles. Based on the obtained results, ultrasonicated garlic extract is a potent antibacterial agent. It can come in handy while developing novel antibiotics against bacteria that have developed resistance.

Immunomodulatory effects of Allium Sativum L. and its constituents against viral infections and metabolic diseases

BACKGROUND

Allium sativum L., or garlic, is one of the most studied plants worldwide within the field of traditional medicine. Current interests lie in the potential use of garlic as a preventive measure and adjuvant treatment for viral infections, e.g., SARS-CoV-2. Even though it cannot be presented as a single treatment, its beneficial effects are beyond doubt. The World Health Organization has deemed it an essential part of any balanced diet with immunomodulatory properties.

OBJECTIVE

The aim of the study was to review the literature on the effects of garlic compounds and preparations on immunomodulation and viral infection management, with emphasis on SARS-CoV-2.

METHOD

Exhaustive literature search has been carried out on electronic databases.

CONCLUSION

Garlic is a fundamental part of a well-balanced diet which helps maintain general good health. The reported information regarding garlic's ability to beneficially modulate inflammation and the immune system is encouraging. Nonetheless, more efforts must be made to understand the actual medicinal properties and mechanisms of action of the compounds found in this plant to inhibit or diminish viral infections, particularly SARS-CoV-2. Based on our findings, we propose a series of innovative strategies to achieve such a challenge in the near future.

A comprehensive review on antimicrobial face masks: an emerging weapon in fighting pandemics

The world has witnessed several incidents of epidemics and pandemics since the beginning of human existence. The gruesome effects of microbial threats create considerable repercussions on the healthcare systems. The continually evolving nature of causative viruses due to mutation or re-assortment sometimes makes existing medicines and vaccines inactive. As a rapid response to such outbreaks, much emphasis has been placed on personal protective equipment (PPE), especially face mask, to prevent infectious diseases from airborne pathogens. Wearing face masks in public reduce disease transmission and creates a sense of community solidarity in collectively fighting the pandemic. However, excessive use of single-use polymer-based face masks can pose a significant challenge to the environment and is increasingly evident in the ongoing COVID-19 pandemic. On the contrary, face masks with inherent antimicrobial properties can help in real-time deactivation of microorganisms enabling multiple-use and reduces secondary infections. Given the advantages, several efforts are made incorporating natural and synthetic antimicrobial agents (AMA) to produce face mask with enhanced safety, and the literature about such efforts are summarised. The review also discusses the literature concerning the current and future market potential and environmental impacts of face masks. Among the AMA tested, metal and metal-oxide based materials are more popular and relatively matured technology. However, the repeated use of such a face mask may pose a danger to the user and environment due to leaching/detachment of nanoparticles. So careful consideration is required to select AMA and their incorporation methods to reduce their leaching and environmental impacts. Also, systematic studies are required to establish short-term and long-term benefits.

Influence of dietary supplementation of Crassocephalum crepidioides leaf on growth, immune status, caecal microbiota, and meat quality in broiler chickens

The effect of dietary supplementation of Crassocephalum crepidioides leaf powder (CCLP) in comparison with oxytetracycline and butylated hydroxyanisole (BHA) on growth, caecal microbiota, immune status, blood chemistry, carcass traits, meat quality, and oxidative stability in broiler chickens was evaluated. Two hundred and eighty 1-day-old Arbor acre chicks were randomly assigned to a basal diet containing either no additive (control, CON), 400 ppm oxytetracycline + 150 ppm BHA (ANTIBIOX), 1000 ppm CCLP (CCLP-1), or 2000 ppm CCLP (CCLP-2) for 42 days. Each dietary group had seven replicates with ten birds per replicate. Supplemented birds had higher (P < 0.05) feed efficiency, hemoglobin, and hematocrit compared with the CON birds. Diet did not affect feed intake, body weight gain, splenic interleukin-1β, interleukin-6, interleukin-10, and serum IgM. The CCLP-2 birds had lower (P < 0.05) serum total and LDL cholesterol than did birds fed other treatments. Salmonella spp. and Escherichia coli counts and serum IgG were higher in the CON birds than in the supplemented birds. The ANTIBIOX birds had lower (P < 0.05) Lactobacillus spp. count, and higher (P < 0.05) E. coli count compared with the CCLP-supplemented birds. Carcass, muscle pH, and cook loss were not affected by diet. The CON breast meat had higher drip loss and lower redness than did the breast meat of the supplemented birds. Carbonyl content and TBARS value in the thigh and breast meat of the supplemented birds were lower (P < 0.05) than those of the CON birds. These results infer that CCLP exhibited antioxidant and antimicrobial properties that were comparable to those of BHA and oxytetracycline in the diet of broiler chickens.

Nanoencapsulation (in vitro and in vivo) as an efficient technology to boost the potential of garlic essential oil as alternatives for antibiotics in broiler nutrition

The addition of essential oil (EO) as chitosan encapsulated can increase the efficiency of these oils in broiler feeding. Therefore, the objective of the current research was to explore the antibacterial and antioxidant potential of garlic essential oil (GEO) (free vs. nanoencapsulated) and their effects on performance, gene expression of mucin2, microbial, and morphology of intestine in broilers. A total of 900 1-day-old male broilers (Ross 308) were assigned to six dietary treatments (0, 100, and 200 mg/kg free GEO and 0 (contain of chitosan), 100 and 200 mg/kg nanoencapsulated GEO) with a 2 × 3 factorial arrangement based on completely randomized design. Garlic essential oil encapsulation with chitosan significantly enhanced antibacterial and antioxidant parameters. At 100 mg/kg nanoencapsulated GEO had significant (P < 0.01) advantages in improving BW gain (BWG) (22-42 and 0-42) and feed conversion ratio (FCR) (0-42). Maximum feed intake (FI) was also associated with the control group (P < 0.05). Broilers fed on 100 mg/kg of nanoencapsulated GEO showed higher villi length and width relative to other treatments and villi length to crypt depth ratio as well (P < 0.01). The nanoencapsulation process of GEO (P < 0.01) affected the Lactobacilli population in the digesta of ileo-caecum and mucin2 gene expression. In broiler chickens, the tested EO, especially nanoencapsulated type, enhanced more evaluated parameters. Because of its ideal properties, nanoencasulating with chitosan may also be an effective and inexpensive way to protect bioactive compounds and improve GEO effects in broiler chickens.

Antiviral potential of garlic (Allium sativum) and its organosulfur compounds: A systematic update of pre-clinical and clinical data

BACKGROUND

Garlic (Allium sativum L.) is a common herb consumed worldwide as functional food and traditional remedy for the prevention of infectious diseases since ancient time. Garlic and its active organosulfur compounds (OSCs) have been reported to alleviate a number of viral infections in pre-clinical and clinical investigations. However, so far no systematic review on its antiviral effects and the underlying molecular mechanisms exists.

SCOPE AND APPROACH

The aim of this review is to systematically summarize pre-clinical and clinical investigations on antiviral effects of garlic and its OSCs as well as to further analyse recent findings on the mechanisms that underpin these antiviral actions. PubMed, Cochrane library, Google Scholar and Science Direct databases were searched and articles up to June 2020 were included in this review.

KEY FINDINGS AND CONCLUSIONS

Pre-clinical data demonstrated that garlic and its OSCs have potential antiviral activity against different human, animal and plant pathogenic viruses through blocking viral entry into host cells, inhibiting viral RNA polymerase, reverse transcriptase, DNA synthesis and immediate-early gene 1(IEG1) transcription, as well as through downregulating the extracellular-signal-regulated kinase (ERK)/mitogen activated protein kinase (MAPK) signaling pathway. The alleviation of viral infection was also shown to link with immunomodulatory effects of garlic and its OSCs. Clinical studies further demonstrated a prophylactic effect of garlic in the prevention of widespread viral infections in humans through enhancing the immune response. This review highlights that garlic possesses significant antiviral activity and can be used prophylactically in the prevention of viral infections.

Effect of Alliaceae Extract Supplementation on Performance and Intestinal Microbiota of Growing-Finishing Pig

Simple Summary

The increasing interest in phytogenics for use with livestock, especially swine and poultry, is mainly due to their antimicrobial, antioxidant, growth-promoting, and gut microbiome modulation properties, which makes them ideal candidates to mitigate the negative effects of the ban on antibiotic growth promoters in the European Union. We tested the ability of Allium spp. extract (containing garlic and onion), one of the best-known phytogenics, used in pig feed, to improve growth performance through modulation of the microbiome and changes in the metabolism of short-chain fatty acids in the gut tract. The promising results obtained in the present study suggested that Allium spp. extracts had the potential to be used in feeding pigs to improve growth performances by modulating the microbiota and metabolism of short-chain fatty acids.

Abstract

The aim of the present study was to ascertain whether an Allium spp. extract rich in organosulfur compounds, such as propyl thiosulfonate (PTSO), added to the feed of growing-finishing pigs at 5 g/kg enhances growth performance or affects the fecal microbiome, the levels of short-chain fatty acids, or the antioxidant capacity of the animals. Fifty male growing pigs (large white) of 23.07 ± 2.87 kg average body weight were randomly allotted to two treatments in a 103-day trial. The trial was divided into two periods, an initial growing phase (56-days) and a finishing phase (47-days). Two dietary treatments for each phase (growing and finishing) were used: a control diet (CON) and an experimental diet consisting of the control diet to which 5 g/kg of Allium spp. extract was added to substitute sepiolite (GAR). Throughout the study, body weight, average daily gain (kg/day, ADG), feed intake (kg/day), and feed conversion ratio (kg/kg) were measured, while the backfat thickness and muscle depth were determined at the end of the study. Besides, feces samples were taken for bacterial counts by means of real-time PCR and short-chain fatty acid (SCFA) profile determination, and the antioxidant capacity was assessed in serum and saliva. In the animals receiving Allium spp. extract (5 g/kg) in the feed, ADG increased (p < 0.05) throughout the trial, Salmonella spp. and Clostridium spp. counts in feces had decreased (p < 0.05) when measured on day 56, and, by day 103, Salmonella spp., Clostridium spp., and Enterobacteriaceae counts had decreased (p < 0.05) and Lactobacillus spp. counts had increased (p < 0.01) in feces. Regarding the SCFA profile in feces and antioxidant capacity measured in serum and saliva, supplementation with Allium spp. extract significantly increased the levels of propionic, isobutyric, and isovaleric acids and the percentage of total branched fatty acids, while the c2/c3 and (c2 + c4)/c3 ratios were lower (p < 0.05) in feces; the Trolox equivalent antioxidant capacity and the cupric reducing antioxidant capacity levels in serum were significantly higher in the same pigs on day 103 than on day 0. Consequently, based on the current results, Allium spp. extract rich in organosulfur compounds, added to the diet at 5 g/kg, had a beneficial effect on the microbiota and would seem to be a possible alternative for increasing the growth performance of growing-finishing pigs. However, further studies on the effects of Allium spp. supplementation on carcass quality are necessary.

Bioactivities of Allium longicuspis Regel against anthracnose of mango caused by Colletotrichum gloeosporioides (Penz.)

The present study focused on the effect of Allium longicuspis extracts (ALE) against anthracnose of mango fruit. In vitro tests (mycelial growth and conidial germination) showed that, ALE concentrated from 0.75 to 2.5 g L^-1 completely inhibited the growth of Colletotrichum gloesporioides. Cytoplasmic discharge, mycelial and conidial blasts were clearly observed when applied with ALE. The minimum effective concentration (MEC) of ALE at 0.75 g L¹ can be applied as protective, curative and simultaneous treatment in mango fruit to inhibit the anthracnose infection. Efficacy of garlic extract was relatively superior to synthetic fungicide based on protective, curative and simultaneous treatments. Twenty chemical components were detected in ALE based on GCMS analysis (Table 1). The six major components were the following: oleyl alcohol, methyl ether (42.04%), γ-sitosterol (15.85%), , 24-norursa-3.12-diene (5.62%), 1-octadecanol methyl ether (4.23%), n-pentadecanol (3.95%) and 2-vinyl-4h-1 3-dithiine (3.76%). The findings support the potential use of ALE as an alternative to synthetic fungicide.

Identification of Essential Oils Including Garlic Oil and Black Pepper Oil with High Activity against Babesia duncani

Some evidence indicated that human babesiosis caused by Babesia duncani has spread widely in North America. However, current therapeutic regimens (atovaquone + azithromycin) for human babesiosis are suboptimal with frequent recrudescence and side effects, and furthermore, there is no specific treatment for human babesiosis caused by B. duncani. Here, we screened 97 essential oils and identified 10 essential oils (garlic, black pepper, tarragon, palo santo, coconut, pine, meditation, cajeput, moringa, and stress relief) at a low concentration (0.001%; v/v) that showed good inhibitory activity against B. duncani in the hamster red blood cell culture model. Among them, garlic oil and black pepper oil performed best, as well as their potential active ingredients diallyl disulfide (DADS) and β-caryophyllene (BCP), respectively. Interestingly, further subculture study indicated that B. duncani could relapse after treatment with current therapeutic drugs atovaquone or azithromycin even at high concentrations. In contrast, the combination of garlic oil or DADS and azithromycin showed eradication of B. duncani at low concentrations without regrowth. These results are encouraging and suggest that the garlic-derived sulfur compound DADS and β-caryophyllene (BCP) may be promising drug candidates for evaluation of their ability to cure persistent B. duncani infections in the future.

Phytochemical Characteristics and Antimicrobial Activity of Australian Grown Garlic (Allium Sativum L.) Cultivars

This study systematically evaluated the main bioactive compounds and associated biological properties of two Australian grown garlic cultivars and commercial non-Australian grown garlic (for comparison purposes only). Additionally, the distribution of bioactive compounds in garlic skin and clove samples was determined to obtain a better understanding of the potential biological functionality of the different garlic parts. The identification and quantification of bioactive compounds was performed by ultra-high performance liquid chromatography with mass spectrometry and photodiode array detection (UHPLC-PDA-MS). A principal component analysis was applied to assess the correlation between the determined bioactive compounds and antioxidant capacity as well as antimicrobial activity. The content of phenolic compounds (free and bound forms) in the garlic skin samples was significantly (p < 0.05) higher than that of the garlic cloves, and was also higher (p < 0.05) in the Australian grown cultivars compared to the commercial non-Australian grown garlic. Anthocyanins were found in the skin samples of the Australian grown garlic cultivars. The organosulfur compounds were higher (p < 0.05) in the cloves compared to the skin samples and higher (p < 0.05) in the Australian grown cultivars compared to the studied commercial sample. As the richer source of bioactive compounds, the Australian grown garlic cultivars exhibited a significantly (p < 0.05) higher antioxidant capacity and stronger (p < 0.05) antimicrobial activity than the commercial non-Australian grown garlic. The potential of garlic cultivars rich in bioactive compounds for domestic and industrial applications, e.g., condiment and natural food preservative, should be explored further.

Placebo-controlled study on the effects of oral administration of Allium sativum L in postweaning piglets

Postweaning diarrhoea (PWD) due to Escherichia coli is an economically important disease in pig production. In this placebo-controlled study performed in Switzerland, the effects of oral supplementation of Allium sativum L. (garlic, AS) on performance (bodyweight (BW) and daily weight gain (DWG)) and health (body condition and clinical score) were investigated in postweaning piglets. Piglets (n=600) were randomly assigned to the treatment groups (placebo, AS or colistin) and observed from birth until three weeks postweaning. The treatments were administered for the first two weeks postweaning. Faecal dry matter (FDM) and coliform bacteria on pen level were measured weekly. Data were analysed using generalised mixed-effect models in R. BW and DWG of the AS group were significantly higher compared with placebo in the third week postweaning. No differences in body condition and FDM were observed. The clinical score of AS-treated animals was significantly better compared with the colistin group. About 33 per cent of the piglets of the AS and the placebo group had to be treated with antibiotics due to the occurrence of severe PWD. The major finding of this study showed that AS supplementation increased growth performance and improved clinical health, but did not reduce the incidence and severity of PWD.

Effect of supplementing milk replacer with aromatic oregano (Oreganum onites L.) water on performance, immunity and general health profiles of Holstein calves

The purpose of this study was to examine the effects of supplementing milk replacer (MR) with aromatic oregano (Origanum onite L.) water on weaning age, performance during the pre- and post-weaning periods, immune systems, blood parameters and general health of 40 Holstein Friesian calves. The calves fed with oregano water (OW)-supplemented MR were weaned earlier than those in the Control group. There were no statistical differences in the liveweight and body measurements among the groups at the weaning age and post-weaning period. The feed intake of the calves fed with OW was higher than that of calves in the Control group in the pre-weaning period. The OW supplementation significantly increased the faecal firmness of calves (P < 0.05). It also decreased the number of E. coli, Coliforms and Enterobacteriaceae pathogens, but only the amount of Enterobacteriaceae was significantly decreased (P < 0.05). Non-pathogens, such as Lactic acid bacteria, were not affected by OW supplementation. The OW supplementation had no significant effect on hematologic and biochemical blood values. There was significant interaction between age and groups in gamma-glutamyl transpeptidase (P < 0.05). The immunoglobulins (IgA, IgG and IgM) values of calves were steadily higher than those of the calves in the Control group. The general health profiles of the calves improved. It can be concluded that MR containing 1–2% OW fed to calves in the early weaning period is a promising treatment to improve their wellbeing and shorten the weaning period.

Formulation development and evaluation of antimicrobial polyherbal gel

OBJECTIVE

In the recent years, there has been a gradual revival of interest in the use of medicinal plants in developing countries because herbal medicines have been reported safe with minimal adverse side effect especially when compared with synthetic drugs.

METHOD

In the present study we prepared gel formulations (formulations A and B) which comprised of ethanolic extract of Azadirachta indica, Curcuma longa, Allium sativum, Ocimum sactum, Cinnamomum zeylanicum nees and Tamarindus indica in a concentration of 0.1 and 0.5%, respectively in a base. The base was prepared by using carbapol 940, propylene glycol-400, ethanol, methyl paraben, propylparaben, EDTA, triethanolamine and required amount of water in a quantity sufficient to prepare 50g. The prepared formulations were screened for their antimicrobial activity by agar well diffusion technique against S. aureus, B. subtilis, A. niger and E. coli which are representative types of Gram positive and Gram negative organisms. The formulations were also evaluated for appearance and homogeneity, pH, viscosity and rheological studies, spreadability, drug content uniformity, skin irritation test (Patch test) and washability.

RESULT

The results of the studies revealed that both formulation under study viz A and B showed better zone of inhibition as compared with the base. However, formulation B exhibited maximum activity against the selected strains which may be attributed to its greater amount of herbal extracts as compared to formulation A.

CONCLUSION

Based on our research, it could be concluded that these formulations possess antimicrobial activity and can be used safely on human skin.

Anti-diabetic and anti-oxidant potential of aged garlic extract (AGE) in streptozotocin-induced diabetic rats

Background

Although aged garlic extract (AGE) shares some active components with fresh garlic and in spite of its palatability and milder side effects, the anti-diabetic and related anti-oxidant properties of AGE have not been investigated extensively, and the reported findings are inconsistent.

This study investigated the anti-diabetic effects of 3 incremental doses of AGE in streptozotocin (STZ)-induced diabetic rats (fasting blood sugar > 20 mM).

Method

Diabetic rats were divided into a control diabetic group (CD) and AGE-treated diabetic group (AGE-D). The AGE-D was divided into 3 groups and accordingly treated with AGE i.p. at 100, 300 and 600 mg/kg daily for 8 weeks. A control normal group (CN) was also included for reference.

Results

Compared to the CN group, the CD group showed significant loss of body weight (over 50 %); and decreased serum insulin concentration (10 fold) and total anti-oxidant level and catalase activity (45–70 %) in serum, kidney and liver. Conversely, the CD rats had an elevated blood glucose (nearly 4 fold), serum cholesterol (nearly 2 fold) and triglycerides (>2 fold), erythrocyte glycated hemoglobin (GHb, 3 fold) and kidney and liver lipid peroxidation (MDA levels). Treatment with AGE positively reversed the diabetic changes in the targeted parameters to levels significantly lower than those measured in the CD group and the degrees of attenuation were almost dose dependent especially with the two higher doses.

Conclusion

AGE exhibits a dose-dependent ameliorative action on indicators of diabetes in STZ-induced diabetic rats.

Effect of supplementation of allicin on methanogenesis and ruminal microbial flora in Dorper crossbred ewes

Background

Garlic extracts have been reported to be effective in reducing methanogenesis. Related mechanisms are not well illustrated, however, and most studies have been conducted in vitro. This study investigates the effects of supplementary allicin (AL) in sheep diet on in vivo digestibility, rumen fermentation, and shifts of microbial flora.

Methods

Two experiments were conducted using Dorper × thin-tailed Han crossbred ewes. In experiment 1, eighteen ewes (60.0 ± 1.73 kg BW) were randomly assigned for 29 days to either of two dietary treatments: a basal diet or the basal diet supplemented with 2.0 g AL/head·day to investigate supplementary AL on nutrient digestibility and methane emissions. In experiment 2, six ewes (65.2 ± 2.0 kg BW) with ruminal canulas were assigned to the same two dietary treatments as in experiment 1 for 42 days to investigate supplementary AL on ruminal fermentation and microbial flora. The methane emissions were determined using an open-circuit respirometry system and microbial assessment was done by qPCR of 16S rRNA genes.

Results

Supplementary AL increased the apparent digestibility of organic matter (P < 0.001), nitrogen (P = 0.006), neutral detergent fiber (P < 0.001), and acid detergent fiber (P = 0.002). Fecal nitrogen output was reduced (P = 0.001) but urinary nitrogen output was unaffected (P = 0.691), while nitrogen retention (P = 0.077) and nitrogen retention/nitrogen intake (P = 0.077) tended to increase. Supplementary AL decreased methane emissions scaled to metabolic bodyweight by 5.95 % (P = 0.007) and to digestible organic matter intake by 8.36 % (P = 0.009). Ruminal pH was unaffected (P = 0.601) while ammonia decreased (P = 0.024) and total volatile fatty acids increased (P = 0.024) in response to supplementary AL. Supplementary AL decreased the population of methanogens (P = 0.001) and tended to decrease that of protozoans (P = 0.097), but increased the populations of F. succinogenes (P < 0.001), R. flavefaciens (P = 0.001), and B. fibrisolvens (P = 0.001).

Conclusions

Supplementation of AL at 2.0 g/head·day effectively enhanced OM, N, NDF, and ADF digestibility and reduced daily methane emissions (L/kg BW^0.75) in ewes, probably by decreasing the population of ruminal protozoans and methanogens.

Herbal plants and plant preparations as remedial approach for viral diseases

Herbal plants, plant preparations and phytoconstituents have proved useful in attenuating infectious conditions and were the only remedies available, till the advent of antibiotics (many being of plant origin themselves). Among infectious diseases, viral diseases in particular, remain the leading cause of death in humans globally. A variety of phytoconstituents derived from medicinal herbs have been extensively studied for antiviral activity. Based on this rationale, an online search was performed, which helped to identify a large number of plant species harboring antiviral molecules. These herbal sources have been reported individually or in combinations across a large number of citations studied. Activities against rabies virus, Human immunodeficiency virus, Chandipura virus, Japanese Encephalitis Virus, Enterovirus, Influenza A/H1N1 and other influenza viruses were discovered during the literature search. This review includes all such plant species exhibiting antiviral properties. The review also encompasses composition and methodologies of preparing various antiviral formulations around the globe. An elaborate section on the formulations filed for patent registration, along with non-patented formulations, has also been included in this article. To conclude, herbal sources provide researchers enormous scope to explore and bring out viable alternatives against viral diseases, considering non-availability of suitable drug candidates and increasing resistance to existing drug molecules for many emerging and re-emerging viral diseases.

Effects of two herbal extracts and virginiamycin supplementation on growth performance, intestinal microflora population and Fatty Acid composition in broiler chickens

The competency of garlic and pennywort to improve broiler chicken growth and influence intestinal microbial communities and fatty acid composition of breast meat were studied. Two hundred forty, "day-old" chicks were randomly allocated to 4 treatment groups consisting of 6 replications of 10 chicks in each pen. The groups were assigned to receive treatment diets as follows: i) basal diet (control), ii) basal diet plus 0.5% garlic powder (GP), iii) basal diet plus 0.5% pennywort powder (PW) and iv) 0.002% virginiamycin (VM). Birds were killed at day 42 and intestinal samples were collected to assess for Lactobacillus and Escherichia coli. The pectoralis profundus from chicken breast samples was obtained from 10 birds from each treatment group on day 42 and frozen at -20°C for further analyses. Fatty acid profile of breast muscles was determined using gas liquid chromatography. Feed intake and weight gain of broilers fed with GP, PW, and VM were significantly higher (p<0.05) compared to control. Feeding chicks GP, PW, and VM significantly reduced Escherichia coli count (p<0.05) while Lactobacillus spp count were significantly higher (p<0.05) in the gut when compared to control group on day 42. Supplemented diet containing pennywort increased the C18:3n-3 fatty acid composition of chickens' breast muscle. Garlic and pennywort may be useful in modulating broiler guts as they control the enteropathogens that help to utilize feed efficiently. This subsequently enhances the growth performances of broiler chickens.

Allicin modulates the antioxidation and detoxification capabilities of primary rat hepatocytes

The effect of allicin, an active ingredient of garlic, on lactate dehydrogenase (LDH) leakage, lipid peroxidation, glutathione (GSH) content, and GSH-related enzyme activity was investigated in primary hepatocytes. In this study, allicin was synthesized in our laboratory as an experimental material, and primary hepatocytes isolated from Sprague-Dawley rats were used as an experimental model. According to the results, hepatocytes treated with 10 μM allicin did not differ from the control on LDH leakage during various incubation times. When the hepatocytes were treated with 10 μM allicin, their levels of thiobarbituric acid reactive-substances (TBARS) did not differ significantly from that of the control within the 8-h incubation. However, the TBARS values of hepatocytes treated with 30 and 50 μM allicin were higher compared to the control after incubation for 4 h and 8 h, respectively. The hepatocyte intracellular GSH content was significantly higher than that of the control after 30 μM allicin treatment, but treatment with 50 μM allicin caused a significant GSH depletion after incubation for 4 h or longer. In addition, when hepatocytes were treated for 24 h with 10 or 30 μM allicin, glutathione peroxidase (GPx) activity was significantly increased compared to that of the control, whereas 50 μM allicin treatment for 24 h or longer significantly decreased the GPx activity. Glutathione reductase (GRd) activity was significantly increased when the hepatocytes were treated with 10 μM allicin for 24 h, but GRd activity significantly decreased when the hepatocytes were treated with 50 μM allicin. However, hepatocytes treated for 24 h with 10 or 30 μM allicin showed significantly increased glutathione S-transferase (GST) activity compared to the control. These results suggest that 10 μM allicin potentially enhances the antioxidation and detoxification capabilities of primary rat hepatocytes.

Efficacy of aqueous garlic extract on growth, aflatoxin B1 production, and cyto-morphological aberrations of Aspergillus flavus, causing human ophthalmic infection: topical treatment of A. flavus keratitis

By using agar well diffusion assay, antifungal activity of aqueous extract prepared from Egyptian garlic (Allium sativum L.) was evaluated in vitro against two strains of Aspergillus flavus (OC1 and OC10) causing human ocular infection. The recorded minimum inhibitory concentration (MIC) for growth inhibition of both strains was 3.60 mg/ml. Aqueous garlic extract (AGE) was used in successive in vivo tests as an attempt to cure rabbit's fungal keratitis caused by A. flavus OC1. Findings showed that diluted preparation of AGE was effective topical antifungal agent and succeeded to cure severe A. flavus keratitis in a time course less than 10 days without any observable side effects. Microscopic examination showed that AGE induced deleterious cyto-morphological aberrations in A. flavus target cells. AGE applied to Czapek's broth via contact method was more effective on growth, spores and aflatoxin B1 production than AGE applied to the same broth at the same concentration via fumigation method.

Antibacterial effect of Allium sativum cloves and Zingiber officinale rhizomes against multiple-drug resistant clinical pathogens

OBJECTIVE

To evaluate the antibacterial properties of Allium sativum (garlic) cloves and Zingiber officinale (ginger) rhizomes against multi-drug resistant clinical pathogens causing nosocomial infection.

METHODS

The cloves of garlic and rhizomes of ginger were extracted with 95% (v/v) ethanol. The ethanolic extracts were subjected to antibacterial sensitivity test against clinical pathogens.

RESULTS

Anti-bacterial potentials of the extracts of two crude garlic cloves and ginger rhizomes were tested against five gram negative and two gram positive multi-drug resistant bacteria isolates. All the bacterial isolates were susceptible to crude extracts of both plants extracts. Except Enterobacter sp. and Klebsiella sp., all other isolates were susceptible when subjected to ethanolic extracts of garlic and ginger. The highest inhibition zone was observed with garlic (19.45 mm) against Pseudomonas aeruginosa (P. aeruginosa). The minimal inhibitory concentration was as low as 67.00 µg/mL against P. aeruginosa.

CONCLUSIONS

Natural spices of garlic and ginger possess effective anti-bacterial activity against multi-drug clinical pathogens and can be used for prevention of drug resistant microbial diseases and further evaluation is necessary.

Effects of dietary supplementation of fermented garlic powder on growth performance, apparent total tract digestibility, blood characteristics and faecal microbial concentration in weanling pigs

A total of 144 weanling pigs (5.5 ± 0.42 kg) were used in a 5-week trial to evaluate the effect of fermented garlic powder (FGP) supplementation in weaning pigs. Pigs were randomly allocated to the following four dietary treatments: (i) control (CON; basal diet), (ii) FGP0.5 (CON + 0.5 g/kg FGP), (iii) FGP1 (CON + 1 g/kg FGP), (iv) FGP2 (CON + 2 g/kg FGP). There were six replications with six pigs (three barrows and three gilts) per pen. Pigs fed FGP0.5 treatments increased (p < 0.05) average daily gain (ADG) and average daily feed intake (ADFI) during 3-5 and 0-5 week. No difference was observed on gain/ feed (G/F) ratio in this study. The inclusion of FGP1 and FGP2 treatments increased DM (p < 0.05) digestibility compared with the CON treatment throughout the experiment. The apparent total tract digestibility of N was (p < 0.05) increased by the dietary FGP throughout the experiment. Pigs fed FGP1 and FGP2 treatments increased the lymphocyte concentration (p < 0.05) and RBC concentration compared with the CON group. Dietary FGP decreased the blood total cholesterol (p < 0.05) in comparison with the CON group. The triglyceride (p < 0.05) concentration was decreased in FGP1 and FGP2 treatments compared with those in the CON treatment at the end of the experiment. Pigs fed FGP1 and FGP2 treatments had a lower number of Escherichia coli in faeces on 21 (p < 0.05) and 35 days (p = 0.05) than those in the CON treatment. In conclusion, dietary fermented garlic powder (0.5 g/kg) can improve ADG and ADFI in weanling pigs, but not at higher levels (1 and 2 g/kg). Dietary fermented garlic powder can also increase the nutrient digestibility, lymphocytes and RBC concentrations, but decrease the faecal E. coli concentration in weaning pigs.

Investigating antibacterial effects of garlic (Allium sativum) concentrate and garlic-derived organosulfur compounds on Campylobacter jejuni by using Fourier transform infrared spectroscopy, Raman spectroscopy, and electron microscopy

Fourier transform infrared (FT-IR) spectroscopy and Raman spectroscopy were used to study the cell injury and inactivation of Campylobacter jejuni from exposure to antioxidants from garlic. C. jejuni was treated with various concentrations of garlic concentrate and garlic-derived organosulfur compounds in growth media and saline at 4, 22, and 35°C. The antimicrobial activities of the diallyl sulfides increased with the number of sulfur atoms (diallyl sulfide < diallyl disulfide < diallyl trisulfide). FT-IR spectroscopy confirmed that organosulfur compounds are responsible for the substantial antimicrobial activity of garlic, much greater than those of garlic phenolic compounds, as indicated by changes in the spectral features of proteins, lipids, and polysaccharides in the bacterial cell membranes. Confocal Raman microscopy (532-nm-gold-particle substrate) and Raman mapping of a single bacterium confirmed the intracellular uptake of sulfur and phenolic components. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to verify cell damage. Principal-component analysis (PCA), discriminant function analysis (DFA), and soft independent modeling of class analogs (SIMCA) were performed, and results were cross validated to differentiate bacteria based upon the degree of cell injury. Partial least-squares regression (PLSR) was employed to quantify and predict actual numbers of healthy and injured bacterial cells remaining following treatment. PLSR-based loading plots were investigated to further verify the changes in the cell membrane of C. jejuni treated with organosulfur compounds. We demonstrated that bacterial injury and inactivation could be accurately investigated by complementary infrared and Raman spectroscopies using a chemical-based, "whole-organism fingerprint" with the aid of chemometrics and electron microscopy.

Antibacterial activity of natural spices on multiple drug resistant Escherichia coli isolated from drinking water, Bangladesh

BACKGROUND

Spices traditionally have been used as coloring agents, flavoring agents, preservatives, food additives and medicine in Bangladesh. The present work aimed to find out the antimicrobial activity of natural spices on multi-drug resistant Escherichia coli isolates.

METHODS

Anti-bacterial potentials of six crude plant extracts (Allium sativum, Zingiber officinale, Allium cepa, Coriandrum sativum, Piper nigrum and Citrus aurantifolia) were tested against five Escherichia coli isolated from potable water sources at kushtia, Bangladesh.

RESULTS

All the bacterial isolates were susceptible to undiluted lime-juice. None of them were found to be susceptible against the aqueous extracts of garlic, onion, coriander, pepper and ginger alone. However, all the isolates were susceptible when subjected to 1:1:1 aqueous extract of lime, garlic and ginger. The highest inhibition zone was observed with lime (11 mm).

CONCLUSION

Natural spices might have anti-bacterial activity against enteric pathogens and could be used for prevention of diarrheal diseases. Further evaluation is necessary.

Echinacea purpurea and Allium sativum as immunostimulants in fish culture using Nile tilapia (Oreochromis niloticus)

The study was conducted to evaluate the efficiency of echinacea (E) and garlic (G) supplemented diets as immunostimulant for tilapia (Oreochromis niloticus). Seven treatments were designed including a control (C). Fish were fed on 35% protein diet at a rate of 3% body weight per day. Echinacea (1.0 ppt) and garlic (3%) were incorporated in the feed, which was administered for periods of 1, 2 and 3 months (summer season), followed by basal diet for 4 more months (winter season). Neutrophil adherence and haematocrit values increased in both supplemented groups with prolonging period of application. The neutrophils adherence was significantly increased in all treatments except group administered echinacea for 1 month. The lymphocytic counts were significantly (p < 0.004) elevated that resulted in a significant increase in the total leucocytic count in groups administered echinacea for 1 and 2 months when compared with the control and/or other treatments. The gain in the body weight and specific growth rate was significantly increased in all supplemented groups (p < 0.004) during summer, but remained without any significant increase after winter. The survival rate was significantly high (>85%) in all the supplemented groups. The percentage of protection, after challenge infection using pathogenic Aeromonas hydrophila was the highest in groups supplemented with echinacea and garlic for 3 months after summer and winter seasons. It could be concluded that echinacea and garlic improve the gain in body weight, survival rate and resistance against challenge infection. Both compounds showed extended effects after withdrawal and improved resistance to cold stress during the winter season. However, a full commercial cost benefit analysis is necessary before recommending their application in aquaculture.

Garlic increases antioxidant levels in diabetic and hypertensive rats determined by a modified peroxidase method

Oxidative damage by free radicals has been implicated in the pathogenesis of vascular disease in diabetes and hypertension. In the present study, the total antioxidant status in diabetic and hypertensive rats before and after treatment with garlic (Allium sativum) was determined. The total serum antioxidants were measured by a modified method reported earlier by Miller and coworkers. The reproducibility of the assay was confirmed by determining standard curves for the known antioxidants: trolox (a stable analog of vitamin E), glutathione and vitamin C with interassay correlation coefficients (R(2), n = 10 in triplicate) of 0.9984, 0.9768 and 0.987, respectively, confirming the reliability and reproducibility of the assay. This assay was then used to determine total serum antioxidant levels of streptozotocin-induced diabetic rats and two-kidney one-clip hypertensive rats both before and after 3 weeks of treatment with an aqueous extract of garlic (500 mg/kg IP daily). The serum antioxidant levels of rats after 3 weeks of treatment were significantly higher (P < .001) than the pretreatment levels in both diabetic and hypertensive rats. The increased serum antioxidant levels were paralleled by a decrease in serum glucose in the garlic-treated diabetic rats and lowered systolic blood pressure in the garlic-treated hypertensive rats. We conclude from our study that (i) total antioxidants can be measured by a simple, reproducible, reliable assay and (ii) the total antioxidant status can be significantly improved by treatment with garlic.

SUMO fusion facilitates expression and purification of garlic leaf lectin but modifies some of its properties

Over expression of lectin genes in E. coli often gives inclusion bodies that are solubilised to characterize lectins. We made N-terminal fusion of the Allium sativum leaf agglutinin (ASAL) with SUMO (small ubiquitin related modifier) peptide. The SUMO peptide allowed expression of the recombinant lectin in E. coli, predominantly in soluble form. The soluble fusion protein could be purified by immobilized metal affinity column (IMAC), followed by size exclusion chromatography. The SUMO protease failed to cleave the SUMO peptide from ASAL. This may be due to steric hindrance caused by the homodimer structure of the chimeric ASAL. Some properties like dimerization, haemagglutination and insecticidal properties of the recombinant SUMO-ASAL fusion protein were comparable to the plant derived native lectin. However, glycan array analysis revealed that the carbohydrate binding specificity of the recombinant SUMO-ASAL was altered. Further, the fusion protein was not toxic to E. coli (native ASAL exhibited toxicity). The recombinant lectin was more thermo-labile as compared to the native lectin. Three important findings of this study are: (1) sugar specificity of ASAL can be altered by amino-terminal fusion; (2) anti-E. coli activity of ASAL can be eliminated by N-terminal SUMO fusion and (3) SUMO-ASAL may be a preferred candidate insecticidal protein for the development of transgenic plants.

Garlic derivatives (PTS and PTS-O) differently affect the ecology of swine faecal microbiota in vitro

A number of in vitro experiments were designed to evaluate the effects of two different industrial products, namely PROALLIUM-S-DMC and PROALLIUM-SO-DMC (DMC Research Center, Granada, Spain), obtained from garlic (Allium sativum) on the faecal microbiota of pigs. The effects of three different concentrations (50, 200 and 400 ppm) of the active compounds (PTS and PTS-O, respectively) from both industrial products on the gastrointestinal microbiota of pigs were tested. Growth medium without any additive (0 ppm) was used as control. Predominant bacterial groups (total aerobes, total anaerobes, lactobacilli, bifidobacteria, coliforms, enterobacteria, bacteroides and clostridia) were studied. Results showed that both PTS and PTS-O have significant (P<0.01) antimicrobial activity against every group studied, although enterobacteria and coliforms were the most affected populations (P<0.01). Time kill curves for Escherichia coli and Salmonella typhimurium, two common pathogens of pigs, showed that both compounds had a bactericidal effect against these strains. For the bacterial groups here studied, the antimicrobial effect of PTS-O was significantly (P<0.001) stronger than that of PTS. Trials in vivo are in course to study the potential use of these products as alternatives to antibiotics in pig feeds.