Evaluation of Cinnamomum tamala Oil and Its Phenylpropanoid Eugenol for Their Antifungal and Antiaflatoxigenic Activity

During screening of 20 plant extracts against toxigenic strain of Aspergillus flavus (SK 3NSt), the extract of Cinnamomum tamala was found to exhibit absolute fungitoxic activity (100% growth inhibition). Hence, essential oil of C. tamala was extracted and selected for further investigations. The selected oil was subsequently standardised through physico-chemical and fungitoxic properties. Minimum inhibitory concentration (MIC) of the oil for absolute inhibition of growth of the toxigenic strain of A. flavus (SK 3NSt) was found to be 150 μl/l and oil showed fungicidal nature at its respective MIC. The oil had a broad fungitoxic spectrum. It was found to be absolutely inhibitory to almost all the 11 fungi tested when its fungitoxic spectrum was assayed. The antifungal potency of oil was found to be greater in comparison to some prevalent synthetic fungicides. The oils had the potency to withstand high inoculum density. The oil remained active up to 2 years and was thermostable. In addition, the oil showed significant efficacy in arresting aflatoxin B₁ secretion by the toxigenic strain (SK 3NSt) of A. flavus at 750 μl/l. GC-MS analysis of the oil led to the identification of main components of oil viz. eugenol (45.58%), β-pinene (10.03%), β-myrcene (9.73%), β-ocimene (4.51%), β-costol (3.88%) and thujyl alcohol isomer (2.51%). The efficacy of C. tamala oil as aflatoxin B₁ suppressor is being reported for the first time. Eugenol, the major component of oil showed absolute antiaflatoxigenic efficacy even at 250 μl/l. The high LD₅₀ value (16.94 ml/kg body weight) of oil recorded on mice indicates its non-mammalian toxicity and suggests the recommendation of the oil as a novel and safe post-harvest biological preservative of food commodities for their preservation from contaminating fungi.     

Evaluation of some essential oils as botanical fungitoxicants for the protection of stored food commodities from fungal infestation

Essential oils from different parts of 18 plants belonging to 11 families were extracted and tested against two toxigenic strains of Aspergillus flavus Link through the poisoned food technique. The oil of Mentha arvensis was found to be effective against both strains of A. flavus and completely stopped the radial mycelial growth of A. flavus at 0.10 mg mL^?1. It was found to be superior over the synthetic fungicides tested and showed a broad fungitoxic spectrum against A. niger, A. fumigatus, Botryodiplodia theobromae, Cladosporium cladosporioides, Fusarium oxysporum, Helminthosporium oryzae, Macrophomina phaseolina and Sclerotium rolfsii at 0.10 mg mL^?1. The oil completely inhibited the aflatoxin B1 production by the toxigenic strain of A. flavus at 0.05 mg mL^?1. Moreover, the Mentha oil also exhibited potent antioxidant activity in 2,2′‐azino‐bis‐3‐ethylbenzothiazoline‐6‐sulphuric acid (ABTS) bioassay. Keeping in mind the side effects of synthetic pesticides and the global interest in botanical pesticides for plant protection due to their biodegradable nature, M. arvensis oil may be used as a botanical fungitoxicant against fungal attack to stored food commodities. The antiaflatoxigenic and antioxidant nature of the oil suggest the possibility of its exploitation for enhancing the shelf life of stored food commodities. Copyright © 2007 Society of Chemical Industry     

Isolation, enumeration and PCR characterization of aflatoxigenic fungi from food and feed samples in India

A total of 54 market samples comprising nine different food and feed commodities from Mysore city were examined in order to isolate aflatoxin-producing fungi as well as to assess aflatoxins in the commodities. Thirty-two samples were contaminated with aflatoxigenic fungi and the total mycoflora and aflatoxigenic fungi in different food and feed commodities were in the range of 0.2–260 and 0–100 cfu×10³/g, respectively. In total, 136 fungi were isolated, of which 32 were Aspergillus flavus strains and 26 of them were found to produce aflatoxins. A. flavus group of fungi comprising A. flavus, A. parasiticus, A. oryzae, A. sojae were characterized by using Aspergillus differential medium and PCR. The PCR was performed using two different sets of primers specifically targeted to aflR and omt genes of aflatoxin biosynthesis pathway. Most of the fungi belonging to A. flavus group reacted positively with the primers resulting in expected size amplicons of 796 bp for aflR and 404 bp for omt. Among the nine commodities screened for aflatoxin only, groundnut and groundnut cake were contaminated with aflatoxins B₁ and B₂. The aflatoxin contamination in these commodities exceeded the Indian regulatory limit of 30 μg/kg.     

Efficacy of Acorus calamus L. essential oil as a safe plant‐based antioxidant,Aflatoxin B1 suppressor and broad spectrum antimicrobial against food‐infesting fungi

The study explores the efficacy of Acorus calamus L. essential oil (EO) as a safe plant‐based broad spectrum antifungal, antiaflatoxin, antioxidant food additive. The oil completely inhibited the growth and toxin production of the toxigenic strain of Aspergillus flavus at 0.4 and 0.25 μL mL^?1, respectively. EO exhibited pronounced antifungal activity against sixteen food‐infesting fungal species at 0.5 μL mL^?1. The EO showed strong antioxidant efficacy (IC₅₀ 1.06 μL mL^?1) and nonphytotoxic nature on germination of chickpea seeds. The EO was found nonmammalian toxic showing high LD₅₀ (4877.4 μL kg^?1) for mice (oral, acute). The chemical profile of EO was determined through GC and GC–MS analysis. The findings strengthen the possibility of A. calamus EO as a plant‐based food additive in view of its favourable safety profile, antioxidant and antiaflatoxigenic efficacy and broad spectrum antimicrobial activity against food‐infesting fungi.     

Chemical composition of Ocimum basilicum L. essential oil and its efficacy as a preservative against fungal and aflatoxin contamination of dry fruits

The study presents fungal and aflatoxin contamination of some dry fruits and Ocimum basilicum essential oil (EO) as a plant‐based preservative. During mycoflora analysis, 2045 fungal isolates were recorded from dry fruits and 40% isolates of Aspergillus flavus were toxigenic in nature. The EO of O. basilicum exhibited strong fungitoxicity against toxigenic strain of A. flavus. Its minimum inhibitory concentration (MIC) was recorded at 1.0 μL ml^?1, and it completely inhibited aflatoxin B₁ production at 0.5 μL ml^?1. The oil exhibited broad fungitoxic spectrum and considerably reduced A. flavus isolates from dry fruits when used as fumigant in closed storage containers at 1.0 μL ml^?1. The chemical profile of the EO was standardised through GC–MS analysis. Based on antifungal potency, antiaflatoxigenicity and efficacy as fumigant during storage conditions, O. basilicum EO may be recommended as a botanical preservative for enhancing the shelf life of dry fruits and edible products during storage.     

Antifungal,antiaflatoxin and antioxidant potential of chemically characterized Boswellia carterii Birdw essential oil and its in vivo practical applicability in preservation of Piper nigrum L. fruits

The study explores the chemical profile, antimicrobial and antioxidant activity of Boswellia carterii essential oil (EO). The EO significantly inhibited growth and aflatoxin production by the food borne toxigenic strain of Aspergillus flavus at 1.75 μl/ml and 1.25 μl/ml respectively. It exhibited broad fungitoxic spectrum against 12 food borne moulds and also showed strong antioxidant activity, IC₅₀ value and % inhibition of linoleic acid peroxidation being 0.64 μl/ml and 51.68% respectively. The antifungal action of EO was observed in terms of reduction in ergosterol content of plasma membrane of A. flavus. As fumigant in food system in storage containers, the EO provided 65.38% protection against fungal deterioration of Piper nigrum. GC–MS results revealed 31 components of EO. The chemically characterized B. carterii EO may thus be recommended as plant based preservative in view of its antifungal, antiaflatoxigenic, antioxidant activity and efficacy in food system.     

Assessment of Pelargonium graveolens oil as plant‐based antimicrobial and aflatoxin suppressor in food preservation

BACKGROUND: Contamination of stored food commodities by moulds and mycotoxins results in qualitative as well as quantitative losses. Most of the synthetic antimicrobials used for preservation of stored food items produce side effects in the form of residual and mammalian toxicity. Recently some higher plant products have been recommended as safe alternatives of such synthetic antimicrobials. In the present investigation antifungal efficacy of some essential oils was evaluated against two toxigenic strains of Aspergillus flavus with special reference to the oil of Pelargonium graveolens to investigate its potential to inhibit aflatoxin B₁ secretion. RESULTS: Essential oil of P. graveolens exhibited absolute fungitoxicity against both the toxigenic strains of A. flavus. The minimum inhibitory concentration of the oil was found to be 0.75 g L^?1 and exhibited a fungistatic nature. It was found superior over the synthetic fungicides tested and exhibited a broad fungitoxic spectrum. The oil showed excellent anti‐aflatoxigenic efficacy as it completely inhibited aflatoxin B₁ production even at 0.50 g L^?1. CONCLUSION: This is the first report on the aflatoxin B₁ inhibitory nature of P. graveolens oil. It may be recommended as a novel plant‐based antimicrobial as well as aflatoxin B₁ suppressor over synthetic preservatives in food protection. Copyright © 2008 Society of Chemical Industry     

Evaluation of chemically characterised essential oils of Coleus aromaticus,Hyptis suaveolens and Ageratum conyzoides against storage fungi and aflatoxin contamination of food commodities

The result of the present investigation explores the efficacy of chemically characterised essential oils (EOs) of Coleus aromaticus, Hyptis suaveolens and Ageratum conyzoides as antifungal and antiaflatoxigenic agent against some storage fungi and the toxigenic strain of Aspergillus flavus (Saktiman 3NSt). Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of these EOs were also determined against the toxigenic strain of A. flavus (Saktiman 3NSt). The EO from C. aromaticus was found to be most effective exhibiting MIC and MFC at 0.1μL mL^?1. The EOs also completely checked aflatoxin B₁ synthesis in concentration‐dependent manner. In addition, fumigation of stored wheat samples with EOs exhibited remarkable protection (>80%) from fungal infestation showing their efficacy during in vivo storage conditions. Based on the results of the present investigation, the EOs of C. aromaticus, H. suaveolens and A. conyzoides may be recommended as novel plant‐based antifungal and aflatoxin B₁ suppressor over the synthetic preservatives.     

Efficacy of chemically characterized Ocimum gratissimum L. essential oil as an antioxidant and a safe plant based antimicrobial against fungal and aflatoxin B1 contamination of spices

The paper reports the essential oil (EO) of Ocimum gratissimum as plant based preservative and recommends its application as a nontoxic antimicrobial and antiaflatoxigenic agent against fungal and aflatoxin contamination of spices as well their shelf life enhancer in view of its antioxidant activity. The EO exhibited antifungal activity against fungal isolates from some spices and showed better efficacy as fungitoxicant than prevalent fungicide Wettasul-80. The EO also completely checked the aflatoxin B₁ (AFB₁) synthesis by the toxigenic strains LHP-6 and LHP-10 of A. flavus isolated from Piper nigrum and Myristica fragrans respectively at 0.6 ??l/ml and 0.5 ??l/ml, respectively. In addition, EO showed antioxidant activity through DPPH free radical scavenging and ??-carotene-linoleic acid bleaching assay. Methyl cinnamate (48.29%) and ??-terpinene (26.08%) were recorded the major components of the oil through GC-MS analysis. The EO was found non-mammalian toxic showing high LD₅₀ (11622.67 ??l/kg) during oral toxicity on mice.     

Antiaflatoxigenic and antioxidant activity of an essential oil from Ageratum conyzoides L.

BACKGROUND: Aflatoxin contamination of various commodities can occur as a result of infection, mainly by Aspergillus flavus and Aspergillus parasiticus. Every year, almost 25% of the world's food supply is contaminated by mycotoxins. Aflatoxins B₁, B₂, G₁ and G₂, which occur naturally, are significant contaminants of a wide variety of commodities. A number of biological activities have been associated with Ageratum conyzoides. We have therefore investigated the antiaflatoxigenic, antioxidant and antimicrobial activity of essential oils of A. conyzoides. This could help to turn A. conyzoides, a nuisance weed, into a resource. RESULTS: The essential oil of Ageratum conyzoides L. shows the presence of 12 compounds when analyzed by gas chromatography–mass spectrometry. The growth and aflatoxin production of the toxigenic strain Aspergillus parasiticus was completely inhibited by essential oil. All the studied concentrations of the oil demonstrate a reduction in mycelia growth and decreased production of different aflatoxins in fungi, as revealed by liquid chomatographic–tandem mass spectrometric analysis. Volatiles from macerated green leaf tissue of A. conyzoides were also effective against A. parasiticus. The strongest antibacterial activity was observed against the bacteria Staphylococcus aureus and Bacillus subtilis in a disk diffusion bioassay. Essential oil and methanol extract of A. conyzoides L. were assayed for their antioxidant activity. Methanol extract showed the highest antioxidant activity in FRAP and DPPH assay, whereas essential oil showed greater lipid peroxidation inhibition than methanol extract. CONCLUSION: The plant's ethno‐medicinal importance, antioxidant potential, inhibitory activity against the Aspergillus group of fungi and production of aflatoxins may add a new dimension to its usefulness in the protection of stored product. Copyright © 2010 Society of Chemical Industry     

Effects of Tropical Citrus Essential Oils on Growth, Aflatoxin Production, and Ultrastructure Alterations of Aspergillus flavus and Aspergillus parasiticus

Ethyl acetate extracts and hydrodistillated essential oils from five cultivars of tropical citrus epicarps were evaluated for their inhibitory activities against Aspergillus fumigatus, Aspergillus niger, Aspergillus flavus, Aspergillus parasiticus, and Penicillium sp. using disk diffusion and broth microdilution assays. Essential oils prepared from kaffir lime (Citrus hystrix DC) and acid lime (Citrus aurantifolia Swingle) epicarps exhibited stronger antifungal activity to all fungi than their ethyl acetate extracts with minimum inhibitory concentration and minimum fungicidal concentration values of 0.56 and 1.13 mg/ml (dry matter), respectively, against aflatoxin-producing A. flavus and A. parasiticus. The dominant components of the essential oil from kaffir lime were limonene, citronellol, linalool, o-cymene, and camphene, whereas limonene and p-cymene were major components of acid lime essential oil. Pure limonene, citronellal, and citronellol were five to six times less fungicidal than the natural essential oils, indicating the synergistic activity of many active compounds present in the oils. Kaffir and acid lime essential oils significantly reduced aflatoxin production of A. flavus and A. parasiticus, particularly lime essential oil, which completely inhibited growth and aflatoxin production of A. flavus at the concentration of 2.25 mg/ml. Target cell damage caused by acid lime essential oil was investigated under transmission electron microscopy. Destructive alterations of plasma and nucleus membrane, loss of cytoplasm, vacuole fusion, and detachment of fibrillar layer were clearly exhibited in essential-oil-treated cells.     

Assessment of the microbiological safety of salad vegetables and sauces from kebab take-away restaurants in the United Kingdom

The purpose of this study was to establish the microbiological safety of salad vegetables and sauces served in kebab take-away restaurants. Comparison with published microbiological guidelines revealed that 4.7% of 1213 salad vegetable samples were of unsatisfactory microbiological quality due to Escherichia coli and/or Staphylococcus aureus levels at ≥10² cfu g⁻¹. Another 0.3% of salad samples were of unacceptable quality due to S. aureus at ≥10⁴ cfu g⁻¹ (2 samples) or the presence of Salmonella Kentucky (1 sample). Cucumber was the most contaminated salad vegetable with regards to unsatisfactory levels of E. coli (6.0%) or S. aureus (4.5%). Five percent of 1208 sauce samples were of unsatisfactory microbiological quality due to E. coli, S. aureus at ≥10² cfu g⁻¹ and/or Bacillus cereus and other Bacillus spp. at ≥10⁴ cfu g⁻¹. A further 0.6% of sauce samples were of unacceptable quality due to Bacillus spp. (Bacillus subtilis, Bacillus pumilus, Bacillus licheniformis) at ≥10⁵ cfu g⁻¹ or the presence of Salmonella Agbeni (1 sample). More samples of chilli sauce (8.7%) were of unsatisfactory or unacceptable microbiological quality than any other sauce types. The results emphasize the need for good hygiene practices in kebab take-away restaurants handling these types of ready-to-eat products.     

Efficacy of Some Essential Oils Against Aspergillus flavus with Special Reference to Lippia alba Oil an Inhibitor of Fungal Proliferation and Aflatoxin B1 Production in Green Gram Seeds during Storage

During mycofloral analysis of green gram (Vigna radiata (L.) R. Wilczek) seed samples taken from different grocery stores by agar and standard blotter paper methods, 5 fungal species were identified, of which Aspergillus flavus exhibited higher relative frequency (75.20% to 80.60%) and was found to produce aflatoxin B₁. On screening of 11 plant essential oils against this mycotoxigenic fungi, Lippia alba essential oil was found to be most effective and showed absolute inhibition of mycelia growth at 0.28 μL/mL. The oil of L. alba was fungistatic and fungicidal at 0.14 and 0.28 μL/mL, respectively. Oil had broad range of fungitoxicity at its MIC value and was absolutely inhibited the AFB1 production level at 2.0 μL/mL. Chemical analysis of this oil revealed geranial (36.9%) and neral (29.3%) as major components followed by myrcene (18.6%). Application of a dose of 80 μL/0.25 L air of Lippia oil in the storage system significantly inhibited the fungal proliferation and aflatoxin production without affecting the seed germination rate. By the virtue of fungicidal, antiaflatoxigenic nature and potent efficacy in storage food system, L. alba oil can be commercialized as botanical fungicide for the protection of green gram seeds during storage.     

Environmental factors modify carbon nutritional patterns and niche overlap between Aspergillus flavus and Fusarium verticillioides strains from maize

This study examined the utilization patterns of key carbon sources (CS, 24: including key sugars, amino acids and fatty acids) in maize by strains of Aspergillus flavus and Fusarium verticillioides under different water activity (a_w, 0.87–0.98 a_w) and temperature (20–35 °C) values and compared the niche overlap indices (NOI) that estimate the in vitro CS utilization profiles [Wilson, M., Lindow, S.E., 1994. Coexistence among epiphytic bacterial populations mediated through nutritional resource partitioning. Applied and Environmental Microbiology 60, 4468–4477.]. The ability to grow in these key CS in minimal media was studied for 120 h in 12 h steps. The NOI was calculated for inter-species (F. verticillioides–A. flavus) and for intra-species (A. flavus–A. flavus) using CS utilization patterns over the range of interacting environmental conditions. 30 °C, over the whole a_w range examined, was found to be optimal for utilization of the maximum number of CS by A. flavus. In contrast, for F. verticillioides this was more so at 20 °C; 25 °C allowed a suboptimal usage of CS for both species. NOIs confirmed the nutritional dominance of A. flavus at 30 °C, especially at lower a_w levels and that of F. verticillioides at 20 °C, mainly at 0.95 a_w. In other conditions of a_w, based on CS utilization patterns, the data indicated that A. flavus and F. verticillioides occupied different ecological niches. The variability in nutritional sources utilization between A. flavus strains was not related to their ability to produce aflatoxins (AFs). This type of data helps to explain the nutritional dominance of fungal species and strains under different environmental conditions. This could be useful in trying to find appropriate natural biocontrol microorganisms to compete with these mycotoxigenic species.     

ANTIFUNGAL ACTIVITIES OF THYME, CLOVE AND OREGANO ESSENTIAL OILS

The antifungal potential of essential oils of oregano (Origanum vulgare), thyme (Thymus vulgaris) and clove (Syzygium aromaticum) was determined. To establish this antifungal potential, two molds related to food spoilage, Aspergillus niger and Aspergillus flavus, were selected. The agar dilution method was employed for the determination of antifungal activities. The three essential oils analyzed presented inhibitory effects on both molds tested. Oregano essential oil showed the highest inhibition of mold growth, followed by clove and thyme. Aspergillus flavus was more sensitive to thyme essential oil than A. niger. Clove essential oil was a stronger inhibitor against A. niger than against A. flavus.     

The control of Aspergillus flavus with Cinnamomum jensenianum Hand.-Mazz essential oil and its potential use as a food preservative

The essential oil extracted from the bark of Cinnamomum jensenianum Hand.-Mazz was tested for antifungal activity against Aspergillus flavus. Fifty-five components accounting for 96.66% of the total oil composition were identified by GC–MS. The major components were eucalyptol (17.26%) and α-terpineol (12.52%). Mycelial growth and spore germination was inhibited by the oil in a dose-dependent manner. The oil also exhibited a noticeable inhibition on the dry mycelium weight and the synthesis of aflatoxin B₁ (AFB₁) by A. flavus, completely restraining AFB₁ production at 6 μl/ml. The possible mode of action of the oil against A. flavus is discussed based on changes in the mycelial ultrastructure. To confirm the target of the oil in the plasma membrane, studies on the inhibition of ergosterol synthesis were performed. Results show that the oil caused a considerable reduction in the ergosterol quantity. Thus, the essential oil from C. jensenianum can be used as a potential source for food preservative.     

植物挥发油对黄曲霉毒素产生菌及其毒素合成的影响

黄曲霉毒素(AFT)是由黄曲霉(Aspergillus flavus)和寄生曲霉(Aspergillus parasiticus)等曲霉属真菌产生的次生代谢产物,具有致畸、致癌、致突变等作用.AFT污染多种粮食作物及食品,其极强的毒性严重威胁到人体健康.寻找各种黄曲霉毒素抑制剂已成为国内外研究的热点.部分抗生素类药物及化学杀菌剂虽然具有较强的抗黄曲霉作用,但鉴于其毒副作用较明显,使用范围非常有限.近二十年来,人们开始从天然产物中寻找毒副作用低、易降解并且安全性高的黄曲霉抑制剂.本文对天然植物挥发油及其单体成分抑制黄曲霉和寄生曲霉生长并抑制AFT合成,以及在粮食、食品及其包装等方面的应用情况进行综述,为进一步研究植物挥发油类成分的抑菌机制和产品开发提供参考.     

Environmental factors affect efficacy of some essential oils and resveratrol to control growth and ochratoxin A production by Penicillium verrucosum and Aspergillus westerdijkiae on wheat grain

This study determined the efficacy of three essential oils (bay, clove and cinnamon oil) and the antioxidant resveratrol (0–500 μg g⁻¹) on the control of growth and ochratoxin A (OTA) production by Penicillium verrucosum and Aspergillus westerdijkiae (=A. ochraceus) under different water activity (a_w, 0.90, 0.95, 0.995), and temperature (15, 25 °C) conditions on irradiated wheat grain. The most effective treatment (resveratrol) was then tested on natural grain. The ED₅₀ values for growth inhibition by the oils were 200–300 μg g⁻¹ at the a_w and the temperatures tested. For resveratrol, this varied from <50 μg g⁻¹ at 0.90–0.95 a_w to >350 at 0.995a_w at both temperatures. The ED₅₀ values for the control of OTA were slightly lower than for control of growth, with approx. 200 μg g⁻¹ required for the oils and 50–100 μg g⁻¹ of the antioxidant, at 0.90/0.95a_w and both temperatures. In wet grain (0.995a_w), higher concentrations were required. For growth there were statistically significant effects of single-, two- and three-way interactions between treatments except for concentration×temperature and concentration×temperature×essential oil/antioxidant treatment. For OTA control, statistically significant treatments were a_w, temperature×a_w, concentration×temperature, treatment×concentration, and three-way interaction of concentration×a_w×treatment for P. verrucosum and A. westerdijkiae. Subsequent studies were done with the best treatment (resveratrol, 200 μg g⁻¹) on natural wheat grain with either P. verrucosum or A. westerdijkiae at 0.85–0.995a_w and 15/25 °C over 28 days storage. This showed that the populations of the mycotoxigenic species and OTA contamination could be reduced by >60% by this treatment at the end of the storage period.     

Biochemical and thermal characterization of crude exo-polygalacturonase produced by Aspergillus sojae

Crude exo-polygalacturonase enzyme (produced by Aspergillus sojae), significant for industrial processes, was characterized with respect to its biochemical and thermal properties. The optimum pH and temperature for maximum crude exo-polygalacturonase activity were pH 5 and 55 °C, respectively. It retained 60–70% of its activity over a broad pH range and 80% of its initial activity at 65 °C for 1 h. The thermal stability study indicated an inactivation energy of E_d = 152 kJ mol⁻¹. The half lives at 75 and 85 °C were estimated as 3.6 and 1.02 h, respectively. Thermodynamic parameters, ΔH^*, ΔS^* and ΔG^*, were determined as a function of temperature. The kinetic constants K_m and V_max, using polygalacturonic acid as substrate, were determined as 0.424 g l⁻¹ and 80 μmol min⁻¹, respectively. SDS-PAGE profiling revealed three major bands with molecular weights of 36, 53 and 68 kDa. This enzyme can be considered as a potential candidate in various applications of waste treatment, in food, paper and textile industries.     

Use of essential oil from Mentha arvensis L. to control storage moulds and insects in stored chickpea

BACKGROUND: Fungal contamination and Callosobruchus infestation results in qualitative and quantitative losses of chickpea seeds during storage. Most of the synthetic chemicals used as preservatives have adverse effects. Therefore, the antifungal and insecticidal potential of Mentha arvensis essential oil was evaluated to determine whether this could be an eco‐friendly substitute of synthetic preservatives. RESULTS: The stored chickpea seeds were dominated by Aspergillus flavus (46.1%) and 30% isolates among them were found toxigenic. The MIC of Mentha oil against A. flavus was recorded at 400 µL L^?1 and it exhibited broad fungitoxic activity against 14 storage fungi. The oil was found superior to some prevalent synthetic fungicides. Mentha oil showed potent insecticidal activity against Callosobruchus chinensis at different concentrations and exposure times. The oviposition by C. chinensis was completely checked at 10 µL L^?1 while F₁ emergence was completely inhibited at 200 µL L^?1. During in situ experiments, 94.05% protection of the chickpea from C. chinensis by Mentha oil showed superiority over the organophosphate insecticide malathion, where 90.75% protection was recorded. CONCLUSION: The Mentha EO showing potent fungitoxic and insecticidal efficacy and may be recommended as a plant‐based preservative in the management of fungal and insect infestation of chickpea and other pulses during storage. Copyright © 2009 Society of Chemical Industry