Medicinal smoke reduces airborne bacteria

See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/5932423 Medicinal smoke reduces airborne bacteria Article in Journal of Ethnopharmacology · January 2008 DOI: 10.1016/j.jep.2007.08.038 · Source: PubMed CITATIONS READS 24 893 3 authors, including: Puneet Chauhan National Botanical Research Institute - India 109 PUBLICATIONS 745 CITATIONS SEE PROFILE All content following this page was uploaded by Puneet Chauhan on 29 November 2016. The user has requested enhancement of the downloaded file. All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately. Journal of Ethnopharmacology Volume 114, Issue 3, 3 December 2007, Pages 446-451 doi:10.1016/j.jep.2007.08.038 Copyright © 2007 Elsevier Ireland Ltd All rights reserved. Medicinal smoke reduces airborne bacteria Chandra Shekhar Nautiyala, , , Puneet Singh Chauhana and Yeshwant Laxman Neneb a Division of Plant-Microbe Interactions, National Botanical Research Institute, Rana Pratap Marg, Lucknow 226001, India bAsian Agri-History Foundation, 47 ICRISAT Colony-I, Brigadier Sayeed Road, Secunderabad 500009, India Received 19 January 2007; revised 17 August 2007; accepted 22 August 2007. Available online 28 August 2007. Abstract This study represents a comprehensive analysis and scientific validation of our ancient knowledge about the effect of ethnopharmacological aspects of natural products’ smoke for therapy and health care on airborne bacterial composition and dynamics, using the Biolog® microplate panels and Microlog® database. We have observed that 1 h treatment of medicinal smoke emanated by burning wood and a mixture of odoriferous and medicinal herbs (havan sámagri = material used in oblation to fire all over India), on aerial bacterial population caused over 94% reduction of bacterial counts by 60 min and the ability of the smoke to purify or disinfect the air and to make the environment cleaner was maintained up to 24 h in the closed room. Absence of pathogenic bacteria Corynebacterium urealyticum, Curtobacterium flaccumfaciens, Enterobacter aerogenes (Klebsiella mobilis), Kocuria rosea, Pseudomonas syringae pv. persicae, Staphylococcus lentus, and Xanthomonas campestris pv. tardicrescens in the open room even after 30 days is indicative of the bactericidal potential of the medicinal smoke treatment. We have demonstrated that using medicinal smoke it is possible to completely eliminate diverse plant and human pathogenic bacteria of the air within confined space. Keywords: Medicinal smoke; Ethnopharmacology; Antimicrobial activity; Bacteria; Airborne; Pathogen Article Outline 1. Introduction 2. Materials and methods 2.1. Plant material 2.2. Air sampling 2.3. Medicinal smoke treatment 2.4. Bacterial culture media and identification 3. Results and discussion Acknowledgements References 1. Introduction From time immemorial, human beings have used smoke of medicinal plants for curing disorders. Smoke produced from natural substances has been used extensively in many cultures and famous ancient physicians have described and recommended such use. Under the continuous Saraswati–Indus civilization going back to 7500 BC [i.e., 9500 Before Present (B.P.)] (Nigam and Hashimi, 2002) the great rishis (saints) used to perform agnihotra–yagnas to purify the environment as described in Rigveda—the most ancient compilation of knowledge on earth by sublimating the havana sámagri (mixture of wood and odoriferous and medicinal herbs) in the fire accompanied by the chanting of Vedic mantras described in Rigveda—the most ancient compilation of knowledge on earth (Kalyanraman, 2004). The records, written on clay tablets in cuneiform, from Mesopotamia dated about 2600 BC; are still in use today for the treatment of ailments ranging from coughs and colds to parasitic infections and inflammation (Mohagheghzadeh et al., 2006). Smoke produced at high temperatures is a simple way of administering a drug, which exhibits rapid pharmacological activity when inhaled. In early Indian writing (Sushruta 800–600 BC), the fumigation of an operating room with fumes of mustard, butter and salt might be considered an early form of “antisepsis” of the air, although it was also used to get rid of evil spirits (Ayliffe and English, 2003). During 522–486 BC, smoke by burning esfand (Peganum harmala) and/or sandalwood (Santalum album) was used to protect the king from evil and disease (Farahvashi, 2003). Throughout the medieval period, including the terrible years of the bubonic plague caused by the causal bacterium Yersinia pestis, the main prophylactic measure against infectious diseases was fumigation by burning incense, herbs and aromatic essences (Ayliffe and English, 2003). Recently, mono- and multiingredient herbal and non-herbal remedies administered as smoke from 50 countries across the 5 continents are reviewed (Mohagheghzadeh et al., 2006). To the best of our knowledge, no detailed scientific study has ever been conducted to elucidate what effect medicinal smoke from the havan sámagri may have on the bacterial composition in the atmosphere. This paper, therefore, reports on scientific validation of our ancient knowledge on antibacterial activity of the medicinal smoke during the treatment of a room with the medicinal smoke, emanated by burning wood and a mixture of odoriferous and medicinal herbs (havan sámagri, i.e., material for oblation to fire), by generating it within confined spaces so as to purify or disinfect the air and to make the environment cleaner. In this study we have designed an air sampler for microbiological air sampling during the treatment of the room with medicinal smoke. In addition, elimination of the aerial pathogenic bacteria due to the smoke is reported too. 2. Materials and methods 2.1. Plant material Impact of medicinal smoke on aerial bacteria by burning wood and a complex mixture of odoriferous and medicinal herbs (havan sámagri = material used in oblation to fire all over India) obtained from Gurukul Kangri Pharmacy, Haridwar, UA, India, without any rituals and mantras, was studied in an indoor environment. Mixture consisted of Aegle marmelos (L.) Corr. (Rutaceae) wood; Alpinia galanga (L.) Willd. (Zingiberaceae) rhizome; Aquilana malaccensis Lam. (Thymelaeaceae) wood; Aquilana agallocha Roxb. (Thymelaeaceae) wood; Azadirachta indica A. juss (Maliaceae) wood; Butea frondosa Koen. ex Roxb. (Fabaceae) whole plant; Cedrus deodara (Roxb. Ex D. Don) G. Don f. (Pinaceae) rhizome; Cedrus libani Loud. (Pinaceae) bark; Citrullus colocynthis (L.) Schrad. (Cucurbitaceae) fruit; Cocos nucifera L. (Palmae) husk fiber; Commiphora mukul Engl. (Burseraceae) gum resin, Cyperus scariosus R. Br. (Cyperaceae) root; Ervatamia divaricata (L.) Burkill (Apocynaceae) whole plant; Euryale ferox Salisb (Nymphocaceae) whole plant; Ficus bengalensis L. (Moraceae) whole plant; Ficus glomerata Linn. (Moraceae) bark and leaf; Ficus religiosa L. (Moraceae) bark and stem, Mangifera indica Linn. (Anacardiaceae) leaf and wood; Peganum harmala L. (Zygophyllaceae) fruit; Pistacia vera L. (Anacardiaceae) fruit; Prosopis spicigera L. (Mimoseae) leaf; Prunus dulcis (P. Mill.) D.A. Webber (Rosaceae) fruit; Santalum album L. (Santalaceae) wood; Sesamum indicum L. (Pedaliaceae) seed; Syzygium aromaticum (L.) Merrill and Perry (Myrtaceae) bud; Valeriana wallichii DC. (Valerianaceae) root; Vitis vinifera L. (Vitaceae) fruit and seed; Withania somnifera (L.) Dunal (Solanaceae) root and Zanthoxylum armatum DC. (Rutaceae) fruit and seed. Odoriferous substances consists of Crocus sativus L. (Iridaceae) stigma; Mimulus moschatus (Scrophulariaceae) flower, Gelidium amansii f. elegans (Kützing) Okamura (N.O. Algae) thallus; Tabernaemontana divaricata (L.) R. Br ex Roem et Schult. (Apocynaceae) root; Santalum album L. (Santalaceae) wood; Elettaria cardamomum Maton. (Zingiberaceae) fruit; Pelargonium fragrans Willd. (Geraniaceae) whole plant; Myristica fragrans Houtt. (Myristicaceae) fruit; Cinnamomum camphora Sieb (Lauraceae) leaf and Cinnamomum macrocarpum Hook. f. (Lauraceae) leaf; substances with healing properties: clarified butter (ghee), milk, fruit, Linum perenne L. (Linaceae) seed, and cereals like Triticum vulgare Vill. (Poaceae) seed; Oryza sativa L. (Poaceae) seed; Hordeum vulgare L. (Poaceae) seed and legumes like Panicum decompositum R. Br. (Gramineae) seed; Vigna mungo (L.) Hepper (Fabaceae) seed; Pisum sativum L. (Fabaceae) seed; Sweet substances: sugar, dried dates, resin, honey, etc; some commonly used herbs are Tinospora cordifolia Miers (Meninspermaceae) leaf; Bacopa monnieri (L.) Pennell (Scrophulariaceae) leaf; Convolvulus pluricaulis (L.) Choisy (Convolvulaceae) whole plant; Mesua ferrea L. (Guttiferae) leaf; Glycyrrhiza glabra L. (Leguminosae) rhizome; Terminalia bellirica (Gaertner) Roxb. (Combretaceae) fruit; dry Zingiber officinale Roscoe (Zingiberaceae) rhizome and Terminalia chebula Retzius (Combretaceae) fruit ([Acharya, 2001] and [Mohagheghzadeh et al., 2006]). 2.2. Air sampling Our own Microbiology media preparation and washing room (space volume: 12.93 ft3) was chosen for the experiment. An apparatus for microbiological air sampling during the treatment of the room with medicinal smoke was designed by using series of Whatman filter paper no. 1 sheet, stainless-steel grid (mesh size 1 mm), polypropylene ring (hole diameter 35 mm), membrane filter (MF; pore size 0.45 μm, diameter 47 mm; Millipore, MA, USA), polypropylene ring, stainless-steel wire mesh, stainless-steel holder connected to a vacuum pump (capacity 1.3 ft3). The sampler developed for this study was effective to prevent clogging of MF, due to incomplete combustion of organic substances and unburnt carbon, which settle as soot (Fig. 1). Air was drawn through the MF using a vacuum pump having a suction capacity at a rate of 1.3 ft3 for 27 min for a total of 1000 l air being filtered through MF (Fig. 1). Fig. 1. Air sampling device for microbiological air sampling during the treatment of the room with medicinal smoke. 2.3. Medicinal smoke treatment Airborne bacteria were collected in the beginning, i.e., 0–1 h after burning 1000 g Mangifera indica wood alone (without mixture of odoriferous and medicinal herbs), in a stainless-steel vessel served as control (Fig. 2). After 1 h, 500 g mixture of odoriferous and medicinal herbs on the burning Mangifera indica wood was added and air sampling was recorded up to 24 h for each round of test in triplicate to elucidate the effect of medicinal smoke on aerial bacteria (Fig. 2), in the closed room. After 24 h the windows and door of the room were opened and airborne bacteria were counted on the 7th, 15th and 30th day. Values are the mean ± S.E. of three samples. Fig. 2. Effect of the medicinal smoke emanated by burning wood (A) and a mixture of odoriferous and medicinal herbs (havan sámagri) (B), on the survival of aerial bacterial population (●). Values are the mean ± S.E. of three samples. 2.4. Bacterial culture media and identification After each sample was taken, the MF was aseptically removed and placed in a 90 mm Petri dish directly on Nutrient Agar (from HI-MEDIA Laboratories Pvt. Ltd., Mumbai, India). After 72 h of incubation at 28 °C, the colonies that developed on the plate were counted and transferred to NA slants (Nautiyal et al., 2006). They were all grown on Biolog® BUG® agar for identification by the Biolog® system (Biolog Inc., Hayward, CA, USA). In preparation for analysis colonies were picked from pure cultures of bacteria and were plated as a lawn of bacteria on to a BUG® agar plate, separate plates were set up for each strain to be analyzed. The Biolog Microlog® Bacterial Identification System consists of databases combined with specialized 96-well plates (test panels). A panel of 95 different substrates gives a very distinctive and repeatable pattern of purple wells for “Metabolic Fingerprint” (June et al., 2006). The Gram-positive and Gram-negative panels and databases were used in this study. 3. Results and discussion From ancient times, human beings have been studying the relationship between ill health and medicine. All cultures have strong traditions of folk medicine that include the use of plants, animals and minerals. The ancient cultures are known for their systematic collection of information on herbs and their rich and welldefined herbal pharmacopoeias. Medicinal plant therapy is based on the empirical findings of hundreds and thousands of years. The ethnopharmacological aspects of natural products’ smoke for therapy and health care have not been studied (Mohagheghzadeh et al., 2006). In this light the present report attains importance as we observed that medicinal smoke emanated from havan sámagri on aerial bacterial population showed very interesting inhibition effects on the aerial bacterial population (Fig. 2). There was no reduction in the number of bacteria of burning Mangifera indica wood alone (Fig. 2). However, medicinal smoke caused over 94% reduction of aerial bacterial counts by 60 min (Fig. 2). In the presence of medicinal smoke bacterial counts were 90, 34, 26, 10, 3, 5, 8 and 12, at 15 min, 30 min, 1 h, 2 h, 4 h, 8 h, 12 h and 24 h, respectively (Fig. 2). Bacterial counts on the 7, 15 and 30 days were 35, 86 and 128 in the room, respectively. Ability of the smoke to purify or disinfect the air and to make the environment cleaner was maintained even after removing the stainless-steel vessel used to generate the medicinal smoke, as evident form over 96% reduction of aerial bacterial counts up to 24 h in the closed room (Fig. 2). Absence of pathogenic bacteria Corynebacterium urealyticum, Curtobacterium flaccumfaciens, Enterobacter aerogenes (Klebsiella mobilis), Kocuria rosea, Pseudomonas syringae pv. persicae, Staphylococcus lentus, and Xanthomonas campestris pv. tardicrescens in the open room even after 30 days is indicative of the bactericidal potential of the medicinal smoke treatment. Work has implications to use the smoke generated by burning wood and a mixture of odoriferous and medicinal herbs, within confined spaces such as animal barns and seed/grain warehouses to disinfect the air and to make the environment cleaner. The occurrences of wild fires during dry seasons and agriculture burning in many parts of the world results in large volumes of volatile compounds being released into the atmosphere ([van Staden et al., 2004] and [Wu et al., 2006]). These smoke clouds contain particulate matter, water vapour, gases and pyrolysis products which can drift over vast distances and may potentially impact on plants outside the immediate vicinity of the fire, either directly as aerosol smoke, or via aqueous media, be it moist soil or water runoff into streams, lakes and impoundments. The fascinating discovery that stimulates seed germination in nature (De Lange and Boucher, 1990) has captured the imagination of plant scientists from a wide range of interdisciplinary fields. The slow combustion of different types of vegetation and organic products at temperatures between 180 and 200 °C produces a highly active, heat stable, long lasting compound, 3methyl-2H-furo [2,3-c]pyran-2-one (1), that stimulates seed germination was isolated from plant-derived smoke water using bioactivity-guided fractionation ([Flematti et al., 2004] and [van Staden et al., 2004]). Recent study has revealed that the effects of smoke extend beyond germination stimulation and can also act to enhance seedling vigour (Sparg et al., 2005). The physiological mechanism resulting in improved vigour is unknown. However, smoke may protect the seed and seedlings against microbial attack (Roche et al., 1997), which can result in higher seedling survival ([Sparg et al., 2005] and [Kulkarni et al., 2007]). Although it is currently unknown how smoke acts to promote germination and improve seedling vigour, aerosol smoke and smoke solutions can potentially be used for a variety of applications related to seed technology. Examples of their potential use include applications in horticulture, agriculture, seed pre-treatment, weed control, ecological management and habitat restoration (Verschaeve et al., 2006). In this study we have demonstrated that 1 h treatment of medicinal smoke produced by burning wood and a mixture of odoriferous and medicinal herbs resulted into complete elimination of plant pathogenic bacteria Burkholderia glumae causing grain and seedling rot of rice (Li et al., 2004), Curtobacterium flaccumfaciens causing wilting in beans (Yin et al., 2005), Pseudomonas syringae pv. persicae causing necrosis of peach tree tissues (Barzic and Guittet, 1996) and Xanthomonas campestris pv. tardicrescens causing black rot in crucifers (Soengas et al., 2007) (Table 1). Work indicates that certain known medicinal constituents from the havan sámagri can thus be added to the burning farm material while disposing unwanted agriculture organic material, in order to reduce plant pathogenic organisms. Table 1. Antibacterial activity of the medicinal smoke emanated by burning wood and a mixture of odoriferous and medicinal herbs (havan sámagri) against the aerial bacteria strains, up to 24 h Bacterial species Time (h) of samplinga 0 1/4 1/2 1 2 4 8 12 24 Gram-positive Bacillus cereus + + + + + + + + + Bacillus megaterium + + + + + + + + − Cellulomonas turbata + + + + + + + + + Clavibacter agropyri + + + + + − − − − Corynebacterium urealyticum + + + + + + + + − Bacterial species Time (h) of samplinga 0 1/4 1/2 1 2 4 8 12 24 Curtobacterium flaccumfaciens + + + + + + + + − Kocuria rosea + + + + − − − − − Leifsonia aquatica + + + + + + + + + Sanguibacter suarezii + + + + + + + + + Sphingomonas yanoikuyae + + + − − − − − − Staphylococcus lentus + + + + + + − − − Staphylococcus xylosus + + + − − − − − − Tsukamurella inchonensis + + + + + + − − − Burkholderia glumae + + + + + + + − − Burkholderia plantarii + + + + + + + − − Curtobacterium citreum + + + + − − − − − Enterobacter aerogenes (Klebsiella mobilis) + + + + + + + + − Flavobacterium johnsoniae + + + + + + + + + Pantoea agglomerans + + + − − − − − − Pseudomonas bathycetes + − − − − − − − − Pseudomonas corrugate + + + + + + + − − Pseudomonas stutzeri + − − − − − − − − Pseudomonas syringae pv. persicae + + + + + + + + − Sphingobacterium multivorum + + + + + + + − − Sphingobacterium spiritovorum + + + + + + + + − Sphingomonas parapaucimobilis + − − − − − − − − Sphingomonas sanguinis + − − − − − − − − Gram-negative Bacterial species Time (h) of samplinga 0 1/4 1/2 1 2 4 8 12 24 Xanthomonas campestris pv. tardicrescens a + − − − − − − − − Results of air sampling in triplicate: (+), survived; (−), not survived. Airborne transmission is known to be a route of infection for diseases. About 15 million (>25%) of 57 million annual deaths worldwide are estimated to be related directly to infectious diseases (WHO, 2004). One most interesting aspect of the work of great applied significance is the ability of the medicinal smoke to completely eliminate human pathogenic bacteria Corynebacterium urealyticum causing urinary tract infection (Nebreda-Mayoral et al., 1994), Kocuria rosea causing catheter-related bacteremia (Altuntas et al., 2004), Staphylococcus lentus causing splenic abscess (Karachalios et al., 2006), Staphylococcus xylosus causing acute polynephritis (Angelina et al., 1982), Tsukamurella inchonensis causing acute myelogenous leukemia (Yassin et al., 1995), Enterobacter aerogenes (Klebsiella mobilis) nosocomial infections (Peres-Bota et al., 2003), Sphingobacterium spiritovorum causing extrinsic allergic alveolitis (Sato and Jiang, 1996) and Sphingomonas sanguinis causing nosocomial nonlife-threatening infections (Li et al., 2004) (Table 1). Smoking has some important benefits compared to other drug routes of administration. It is an inexpensive and simple way of extraction and can be a method of drug use that is acceptable to many people. More importantly, generating smoke reduces the particle size to a microscopic scale thereby increasing the absorption of its active principles. Most of the ancient drugs are still being used in the same dosage and form although smoking today is more often a form of drug abuse than as a therapeutic because of its highly effective and rapid pharmacological action. Whereas inhalation is typically used in the treatment of pulmonary and neurological disorders and directed smoke in localized situations, such as dermatological and genito-urinary disorders, ambient smoke is not directed at the body at all but used as an air purifier. The advantages of smoke-based remedies are rapid delivery to the brain, more efficient absorption by the body and lower costs of production (Mohagheghzadeh et al., 2006). Many of human and plant pathogens reported in Table 1 can easily be considered to be of importance of its potential implications on human health, agricultural productivity, and ecosystem stability; surprisingly little is known regarding the composition or dynamics of the aerial microbial inhabitants. Using a custom high-density DNA microarray, Brodie et al. (2006) have detected in urban aerosols at least 1800 diverse bacterial types, a richness approaching that of some soil bacterial communities. Their work has also revealed the consistent presence of bacterial families with pathogenic members. Thus it is very much plausible that further research will enable more accurate scope of the utility of the use of medicinal smoke against indoor airborne infections. This study represents a comprehensive analysis and scientific validation of the effect of ethnopharmacological aspects of natural products’ smoke on airborne bacterial composition and dynamics. In particular, it highlights the fact that we must think well beyond the physical aspects of smoke on plants in natural habitats and impacts heavily on our understanding of fire as a driving force in evolution. We have demonstrated that using medicinal smoke it is possible to contain diverse pathogenic bacteria of the air we breathe. The work also highlights the fact about medicinal smoke and that a lot of natural products have potential for use as medicine in the smoke form as a form of drug delivery and as a promising source of new active natural ingredients for containing indoor airborne infections within confined spaces used for storage of agriculture commodities. The dynamic chemical and biological interactions occurring in the atmosphere are much more complex than has been previously realized. The findings warrant a need for further evaluation of various ingredients present in the complex mixture of odoriferous and medicinal herbs, individually and in various combinations to identify the active principles involved in the bactericidal property of the medicinal smoke, applied in the above-discussed fashion. Acknowledgments Thanks are due to the Director, National Botanical Research Institute, Lucknow for providing the necessary support. CSN is grateful to Professor A.N. Purohit of the Centre for Aromatic Plants, Selaqui, Dehradun, India for useful discussions. References Acharya, 2001 S.S. Acharya, The Integrated Science of Yagna, Shantikunj, Haridwar, (U.A), India (2001). Altuntas et al., 2004 F. Altuntas, O. Yildiz, B. Eser, K. Gündogan, B. Sumerkan and M. Çetin, Catheter-related bacteremia due to Kocuria rosea in a patient undergoing peripheral blood stem cell transplantation, BMC Infectious Disease 4 (2004), p. 62. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (0) Angelina et al., 1982 D. Angelina, Tselenis-Kotsowilis, M.P. Koliomichalis, T. John and J.T. Papavassiliou, Acute pyelonephritis caused by Staphylococcus xylosus, Journal of Clinical Microbiology 16 (1982), pp. 593–594. Ayliffe and English, 2003 G.A.J. Ayliffe and M.P. English, Hospital Infection from Miasmas to MRSA, Cambridge University Press, Cambridge, UK (2003). Barzic and Guittet, 1996 M.R. Barzic and E. Guittet, Structure and activity of persicomycins, toxins produced by a Pseudomonas syringae pv. persicae/Prunus persica isolate, European Journal of Biochemistry 239 (1996), pp. 702–709. View Record in Scopus | Cited By in Scopus (5) Brodie et al., 2006 E.L. Brodie, T.Z. DeSantis, J.P. Moberg Parker, I.X. Zubietta, Y.M. Piceno and G.L. Andersen, Urban aerosols harbor diverse and dynamic bacterial populations, Proceedings of the National Academy of Sciences 104 (2006), pp. 299–304. De Lange and Boucher, 1990 J.H. De Lange and C. Boucher, Autecological studies on Audouinia capitata (Bruniaceae). I. Plant-derived smoke as a seed germination cue, South African Journal of Botany 56 (1990), pp. 700–703. Farahvashi, 2003 B. Farahvashi, Farhange Zabane Pahlavi, Tehran University Press, Tehran (2003). Flematti et al., 2004 G.R. Flematti, E.L. Ghisalberti, K.W. Dixon and R.D. Trengove, A compound from smoke that promotes seed germination, Science 305 (2004), p. 977. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (73) June et al., 2006 C.M. June, K. Roach, P.N. Levett and M.C. Lavoie, Identification of Streptococcus iniae by commercial bacterial identification systems, Journal of Microbiological Methods 67 (2006), pp. 20–26. Kalyanraman, 2004 Kalyanraman, 2004. Sarasvati (7 volumes), Baba Saheb (Umakanta Keshava) Apte Smarak Samiti, Bangalore. Karachalios et al., 2006 G.N. Karachalios, F.V. Michelis, K.V. Kanakis, I. Karachaliou, R. Koutri and A.K. Zacharof, Splenic abscess due to Staphylococus lentus: A rare entity, Scandinavian Journal of Infectious Diseases 38 (2006), pp. 708–710. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (3) Kulkarni et al., 2007 M.G. Kulkarni, S.G. Sparg and J. Van Staden, Germination and post-germination response of Acacia seeds to smoke–water and butenolide, a smoke-derived compound, Journal of Arid Environments 69 (2007), pp. 177– 187. Article | PDF (309 K) | View Record in Scopus | Cited By in Scopus (5) Li et al., 2004 Y. Li, Y. Kawamura, N. Fujiwara, T. Naka, H. Liu, X. Huang, K. Kobayashi and T. Ezaki, Sphingomonas yabuuchiae sp. nov. and Brevundimonas nasdae sp. nov., isolated from the Russian space laboratory Mir, International Journal of Systematic and Evolutionary Microbiology 54 (2004), pp. 819–825. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (18) Mohagheghzadeh et al., 2006 A. Mohagheghzadeh, P. Faridi, M. ShamsArdakani and Y. Ghasemi, Medicinal smokes, Journal of Ethnopharmacology 108 (2006), pp. 161–184. Article | By in Scopus (3) PDF (1220 K) | View Record in Scopus | Cited Nautiyal et al., 2006 C.S. Nautiyal, S. Mehta and H.B. Singh, Biological control and plant growth-promoting Bacillus strains from milk, Journal of Microbiology and Biotechnology 16 (2006), pp. 184–192. View Record in Scopus | Cited By in Scopus (11) Nebreda-Mayoral et al., 1994 T. Nebreda-Mayoral, J.L. Munoz-Bellido and J.A. Garcia-Rodríguez, Incidence and characteristics of urinary tract infections caused by Corynebacterium urealyticum (Corynebacterium group D2), European Journal of Clinical Microbiology and Infectious Diseases 13 (1994), pp. 600–604. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (18) Nigam and Hashimi, 2002 R. Nigam and N.H. Hashimi, Has sea level fluctuations modulated human settlements in gulf of Khambat (Cambay)?, Journal of Geological Society of India 59 (2002), pp. 583–584. Peres-Bota et al., 2003 D. Peres-Bota, H. Rodriguez, G. Dimopoulos, A. DaRos, C. Melot, M.J. Struelens and J.L. Vincent, Are infections due to resistant pathogens associated with a worse outcome in critically ill patients?, Journal of Infection 47 (2003), pp. 307–316. Article | PDF (174 K) | View Record in Scopus | Cited By in Scopus (11) Roche et al., 1997 S. Roche, J.M. Koch and K.W. Dixon, Smoke enhanced seed germination for mine rehabilitation in the southwest of Western Australia, Restoration Ecology 5 (1997), pp. 191–203. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (59) Sato and Jiang, 1996 K. Sato and H.Y. Jiang, Gram-negative bacterial flora on the root surface of wheat (Triticum aestivum) grown under different soil conditions, Journal of Biology and Fertility of Soils 23 (1996), pp. 273–281. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (14) Soengas et al., 2007 P. Soengas, P. Hand, J.G. Vicente, J.M. Pole and D.A. Pink, Identification of quantitative trait loci for resistance to Xanthomonas campestris pv. campestris in Brassica rapa, Theoretical and Applied Genetics 114 (2007), pp. 637–645. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (4) Sparg et al., 2005 S.G. Sparg, M.G. Kulkarni, M.E. Light and J. Van Staden, Improving seedling vigour of indigenous medicinal plants with smoke, Bioresource Technology 96 (2005), pp. 1323–1330. Article | PDF (403 K) | View Record in Scopus | Cited By in Scopus (18) van Staden et al., 2004 J. van Staden, A.K. Jäger, M.E. Light and B.V. Burger, Isolation of the major germination cue from plant-derived smoke, South African Journal of Botany 70 (2004), pp. 654–659. View Record in Scopus | Cited By in Scopus (33) Verschaeve et al., 2006 L. Verschaeve, J.M. Marnie, E. Light and J. van Staden, Genetic toxicity testing of 3-methyl-2H-furo[2,3-c]pyran-2-one, an important biologically active compound from plant-derived smoke, Mutation Research/Genetic Toxicology and Environmental Mutagenesis 611 (2006), pp. 89–95. Article | PDF (479 K) | View Record in Scopus | Cited By in Scopus (3) WHO, 2004 WHO, 2004. The World Health Report 2004—Changing History (http://www.who.int/whr/2004/en). Wu et al., 2006 C.F. Wu, J. Jimenez, C. Claiborn, T. Gould, C.D. Simpson, T. Larson and L.J. Sally Liu, Agricultural burning smoke in eastern Washington. Part II. Exposure assessment, Atmospheric Environment 28 (2006), pp. 5379–5392. Article | PDF (315 K) | View Record in Scopus | Cited By in Scopus (4) Yassin et al., 1995 A.F. Yassin, F.A. Rainey, H. Brzezinka, J. Burghardt, H.J. Lee and K.P. Schaal, Tsukamurella inchonensis sp. nov, International Journal of Systematic Bacteriology 45 (1995), pp. 522–527. View Record in Scopus | Cited By in Scopus (42) Yin et al., 2005 Y.N. Yin, Y.F. Chen, S.M. Li and J.H. Guo, RAPD analysis of plant pathogenic coryneform bacteria, Wei Sheng Wu Xue Bao 45 (2005), pp. 837–841. Corresponding author. Tel.: +91 522 2206651; fax: +91 522 2206651.