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1.
Summary Palmyrah palm wine, a traditional mild alcoholic beverage of Northern Sri Lanka, is popularly referred to as toddy. It is obtained by the natural fermentation of the sugary sap of the palmyrah palm (Borassus flabellifer L.). The microflora commonly found in palmyrah toddy were identified asSaccharomyces cerevisiae, Sacch. Chevalieri, Kloeckera apiculata, Schizosaccharomyces pombe, Bacillus cereus, B. sphaericus andB. firmus. Of the yeasts, the predominant and best alcoholic fermenter wasSacch. cerevisiae. The efficiency of alcoholle fermentation in natural palmyrah toddy was 56%. This was increased to 69% by adding a pure inoculum ofSacch. cerevisiae into the toddy collecting pots. A further increase in the efficiency to 89% was attained when fresh, sterilized palmyrah sap was fermented withSacch. cerevisiae under laboratory conditions.
Resumen El vino de la palmera palmyrah es una bebida moderadamente alcohólica tradicional del Norte de Sri Lanka a la que se conoce popularmente como toddy. Se obtiene mediante la fermentación natural de la savia azucarada de la Palmyrah (Borassus flabellifer). La microflora que se encuentra en el toddy de Palmyrah se identificó como:Saccharomyces cerevisiae, Sacch. chevalieri,Kloeckera apiculata, Schizosaccharomyces pombe, Bacillus cereus,B. sphaericus, y,B. firmus. De entre las levaduras, la más predominante y también la mejor fermentadora alcohólica fueSacch. cerevisiae.

Résumé Le vin de palme de palmyre, boisson faiblement alcoolisée produite au Nord du Sri Lanka, est vulgairement dénommé toddy, Il est obtenu par fermentation naturelle de la sève sucrée du palmier palmyre (Borassus flabillifer L.). La microflore usuelle du toddy de palmyre est constituée parSaccharomyces cerevisiae, Sacch. chevalieri, Kloeckera apiculata, Schizosaccharomyces pombe, Bacillus cereus, B. sphaericus etB. firmus. Parmi les levures,Sacch. cerevisiae est la plus abondante et le meilleur agent de la fermentation alcoolique.


Paper based on a poster presentation at the VII International Conference on the Global Impacts of Applied Microbiology, Helsinki, 12–16 August 1985.  相似文献   

2.
3.
pPalmyrah palm (Borassus flabellifer) is widely consumed by people in certain tropical countries. The incidence of human malignant lymphomas, mutagenicity and toxicity in rats and bacteria encouraged us to study the potency of palmyrah crude aqueous extracts in inducing sister-chromatid exchanges (SCEs) in human blood lymphocytes in vitro. The extracts induced SCEs in a dose-related manner in both females and males. These effects apparently showed no consistency between batches. This result may be due to the intrinsic variation of different donors in their response to the induction of SCEs by palmyrah extracts. SCE frequency was proportional to chromosome length and SCEs at the centromeric region showed no difficulty in being scored. Concerning methods of short-term cytogenetic testing for detecting mutagenic and carcinogenic chemicals, we found that the SCE test was not more sensitive than the classic chromosome-breakage test.  相似文献   

4.
Polyembryony and twin seedlings are noted in Borassus flabellifer L. Both seedlings arising from a seed have an independent hatistorium, cotyledonary sheath, scale leaf and root system. There are instances where twin seedlings are identical in structure and activity; independent plants develop in the same way as normal seedlings. The haustoria of these seedlings are equal in size and activity. Cases are also recorded with disparity in size and activity between twin seedlings. While the haustorium of the bigger seedling is normal, that of the smaller seedling is reduced.  相似文献   

5.
Visceral leishmaniasis (VL), known as Kala-azar in India, is a parasite transmitted by the bite of the sand fly vector Phlebotomus argentipes. Published information on the species indicates it is a poor flyer, mainly hopping and gliding. This study describes the vector as more arboreal than previously documented. Data collected indicate the ability of P. argentipes and Sergentomyia spp to attain vertical heights in Palmyra palm trees Borassus flabellifer up to 18.4 m above ground level. To determine if sand flies were either climbing the tree trunk to rest in the canopy or flying, sticky traps were set around the tree trunk and checked for captures overnight. CDC traps set in the palm tree canopy resulted in the capture of 5,067 sand flies, 3,990 of which were P. argentipes. Traps were set during daylight hours to determine if sand flies remained and rested in the canopy. A total of 128 sand flies were trapped over 29 trap days in the palm trees. With the CDC traps, 130 P. argentipes and no Sergentomyia spp were captured. The converse was true for the sticky traps set around tree trunks 3 m below the CDC traps. Of the 105 sand flies collected, only one was P. argentipes and 104 were Sergentomyia spp. As reported elsewhere, this indicates Sergentomyia spp tend to climb and hop, wheareas P. argentipes are capable of longer and more sustained flight. Data presented herein suggest that P. argentipes is more exophylic and exophagic than previously reported. These findings have implications for sand fly control.  相似文献   

6.
The palmyra palm Borassus flabellifer,), a multipurpose tree of great utility, occurs extensively in Tamil Nadu state, India. Figuring in history, literature, and folklore of the state, it is exploited for food from the fruit and tuberous seedlings; beverage and sugar from the sap; fiber from the leaf and leafbase for brushes, cordage, weaving, and plaiting; trunk wood for construction and fuel; and numerous minor products. Increasing exploitation of the palmyra threatens the future supply of palm raw materials so important to rural populations. Integrated development of palmyra products for local and export markets, as well as management/conservation measures, are needed both to maximize the economic value of the products and to assure sustained yield from native stands.  相似文献   

7.
The novel triterpene 1 with a dammarane skeleton and a hitherto unknown 17alpha-substitution pattern has been isolated from the Palmyrah palm in low yield and prepared by synthesis in larger quantities. 1 was shown to be an extremely potent immunosuppressant in vitro (MLR; IC50 = 10 ng/ml) and in vivo (DTH; ED50 = 0.01 mg/kg p.o.). A glucocorticoid like activity is excluded.  相似文献   

8.
Purification and characterization of polygalacturonase from banana fruit   总被引:2,自引:0,他引:2  
Polygalacturonase isoenzyme 3 (PG-3) was purified to homogeneity with a specific activity of 0.7 mu katal mg-1 protein from banana fruit pulp. The purified enzyme was a glycoprotein with ca. 8% carbohydrate. The molecular weight of the native enzyme was found to be 90 +/- 10 kDa with a subunit molecular weight of 29 +/- 2 kDa. The enzyme exhibited optimum activity at pH 4.3 and temperature 40 degrees C with activation energy 35.4 kJ mol-1. A unique property of the enzyme was the requirement of -SH groups for the enzyme activity. The enzyme was inhibited by p-CMB and activated by 2-ME and DTT. The inhibition of p-CMB could be reversed by DTT. The enzyme contained eight free -SH groups. The Km of the enzyme was 0.15% for polygalacturonic acid.  相似文献   

9.
Polygalacturonase produced by Streptomyces lydicus was purified to homogeneity by ultrafiltration and a combination of ion exchange and gel filtration chromatographic procedures. The purified enzyme was an exo-polygalacturonase with a molecular weight of 43 kDa. It was optimally active at 50 degrees C and pH 6.0. The enzyme was stable from pH 4.0 to 7.0 and at or below 45 degrees C for 90 min. K(m) value for polygalacturonic acid was 1.63 mg/mL and the corresponding V(max) was 677.8 microM min(-1) mg(-1). The inhibition constant (K(i)) for gluconic acid d-lactone was 20.75 mM. Purified enzyme had been inhibited by N-bromosuccinimide, while l-tryptophan could induce enzyme activity, indicating the involvement of tryptophan at the active site.  相似文献   

10.
Peroxidase from date palm (Phoenix dactylifera L.) leaves was purified to homogeneity and characterized biochemically. The enzyme purification included homogenization, extraction of pigments followed by consecutive chromatographies on DEAE-Sepharose and Superdex 200. The purification factor for purified date palm peroxidase was 17 with 5.8% yield. The purity was checked by SDS and native PAGE, which showed a single prominent band. The molecular weight of the enzyme was approximately 55 kDa as estimated by SDS–PAGE. The enzyme was characterized for thermal and pH stability, and kinetic parameters were determined using guaiacol as substrate. The optimum activity was between pH 5–6. The enzyme showed maximum activity at 55 °C and was fairly stable up to 75 °C, with 42% loss of activity. Date palm leaves peroxidase showed Km values of 0.77 and 0.045 mM for guaiacol and H2O2, respectively. These properties suggest that this enzyme could be a promising tool for applications in different analytical determinations as well as for treatment of industrial effluents at low cost.  相似文献   

11.
Abstract Exopolygalacturonase, endopolygalacturonase and pectinesterase were separated from culture filtrates of Trichoderma reesei QM9414 by Sephadex chromatography. Exopolygalacturonase was characterized by specific cleavage of pectic acid to form d -galactopyranuronic acid, and by the hydrolysis of oligomers (highest reaction rate at pentamer). Polygalacturonase exhibited 2 pH-optima peaks (at 4.8 and 5.1) and 10 bands with enzyme activity by isoelectric focusing (IEF) (p I 4.6–8.5). Pectinesterase showed a pH-optimum at 7.6, and 6 enzyme-activity bands on an IEF zymogram which seemed identical with those of higher plants (tomato, alfalfa).  相似文献   

12.
Purification and characterization of tomato polygalacturonase converter   总被引:2,自引:0,他引:2  
Extracts of ripe tomatoes contain two forms of polygalacturonase (PG I and PG II). A heat-stable component that binds PG II to produce PG I has been isolated from tomato fruit. This component has been named polygalacturonase converter (PG converter). The PG converter has been purified by gel filtration, ion-exchange chromatography and chromatofocusing. It appears to be a protein with a relative molecular mass of 102000. It was readily inactivated by papain and pronase. The converter was labile at alkaline conditions, and treatment of PG I at pH 11 released free PG II. A similar factor with a lower molecular mass was extracted from tomato foliage.  相似文献   

13.
An endo-polygalacturonase, named PGI, was purified to homogeneity from the culture filtrate of Aspergillus kawachii IFO 4033 grown in a glucose-tryptone medium. The molecular mass of PGI was estimated to be 60 kDa by SDS-PAGE and 40 kDa by gel filtration on Sephacryl S-100. The isoelectric point was 3.55 as determined by isoelectic focusing. PGI exhibited binding properties to ConA-Sepharose suggesting that the protein is glycosylated. The N-terminal amino acid sequence was also determined as S-T-C-T-F-T-D-A-A-T-A-S-E-S-K. The remarkable property of PGI was its high activity in the pH range 2.0-3.0 towards soluble and insoluble substrates, while being inactive at pH 5.0. Enzyme stability at low pHs was markedly enhanced by different compounds, such as proteins, polysaccharides, simple sugars and the substrate pectin. PGI was very efficient to extract pectin from lemmon protopectin and to macerate carrot tissues at pH 2.0. These properties make PGI an interesting biocatalyst for industrial applications under highly acidic conditions.  相似文献   

14.
Soluble peroxidase (POD) from oil palm leaf was purified by (NH(4))(2)SO(4) precipitation, anion exchange chromatography and molecular exclusion chromatography. The purification grade obtained was 429 yielding 54% of the enzyme activity. Electrophoresis of purified enzyme under denatured conditions revealed M(r) of 48+/-2 kDa. It has an optimum pH of 5 and it exhibited very high pH and thermal stabilities. K(m) for guaiacol, ABTS and pyrogallol were 3.96, 1 and 0.84 mM, respectively. Immunocytochemical localization studies showed that soluble POD was mainly located in the vascular bundles and epidermis of leaf.  相似文献   

15.
Airborne pollen grains of Borassus flabellifer were recorded at Madhyamgram, during February to June 1995–1996 commensurate with the plants flowering season. The following year (1996–1997), the exposed Burkard tape segments with the optimal and minimal daily concentrations were divided into two longitudinal equal halves. For each segment, after immunoblotting, one half was incubated with human sera having high IgE titer against Borassus, and the other half with anti-Borassus rabbit sera for the detection of allergen and antigen respectively. Antigen detection was performed by general immunoblotting method, whereas the allergens were detected by chemiluminescence. The occurrence of the pollen grains in air was compared and correlated with that of the allergen and antigen. The number of allergen and antigen spots were always found to be higher than airborne pollen with great size variation due to the presence of exine free protein particles originating from the pollen grains. The number of allergen spots was always lower than the antigen spots. The occurrence of pollen grains and antigen spots showed stronger positive correlation compared with allergen spots. The peak hours for the occurrence of pollen grains, allergens and antigens were recorded. It is evident from this study that the application of direct aeroallergen monitoring method will be highly useful in allergological research.  相似文献   

16.
An NADP+ —dependent reversible 3-hydroxycarboxylate oxidoreductase present in Clostridium tyrobutyricum has been purified. As judged by gel electrophoresis the enzyme was pure after a 940-fold enrichment by four chromatographic steps. Its molecular mass was estimated to be 40–43 kDa. The enzyme was most active at pH 4.5 in the reduction of 3-oxobutyrate. Other substrates were 3-oxovalerate, 3-oxocaproate, 3-oxoisocaproate and 4-chloro-3-oxobutyrate. Except for the latter all substrates were converted enantioselectively to (S)-3-hydroxy acids in the presence of NADPH. 4-Chloro-3-oxobutyrate was reduced to the (R)-3-hydroxy acid. The specific activity of the enzyme was about 1400 mol min–1 mg–1 protein for the reduction of 3-oxobutyrate at pH 5.0. The Michaelis constant (K m) values for 3-oxobutyrate, 3-oxovalerate and 3-oxocaproate were determined to be 0.22, 1.6 and 3.0 mM, respectively. The K m values for dehydrogenation of (S)-3-hydroxybutyrate, (S)-3-hydroxyvalerate and (S)-3-hydroxycaproate were found to be 2.6, 1.1 and 5.2 mM, respectively. The identity of 43 of the first 45 N-terminal amino acid residues has been determined. So far such enzyme activities have been described in eucaryotes only.Dedicated to Prof. A. Trebst on the occasion of his 65th birthday  相似文献   

17.
We report for the first time kinetic and thermodynamic properties of soluble acid invertase (SAI) of sugarcane (Saccharum officinarum L.) salt sensitive local cultivar CP 77-400 (CP-77). The SAI was purified to apparent homogeneity on FPLC system. The crude enzyme was about 13 fold purified and recovery of SAI was 35%. The invertase was monomeric in nature and its native molecular mass on gel filtration and subunit mass on SDS-PAGE was 28 kDa. SAI was highly acidic having an optimum pH lower than 2. The acidic limb was missing. Proton transfer (donation and receiving) during catalysis was controlled by the basic limb having a pKa of 2.4. Carboxyl groups were involved in proton transfer during catalysis. The kinetic constants for sucrose hydrolysis by SAI were determined to be: km = 55 mg ml?1, kcat = 21 s?1, kcat/km = 0.38, while the thermodynamic parameters were: ΔH* = 52.6 kJ mol?1, ΔG* = 71.2 kJ mol?1, ΔS* = ?57 J mol?1 K?1, ΔG*E–S = 10.8 kJ mol?1 and ΔG*E–T = 2.6 kJ mol?1. The kinetics and thermodynamics of irreversible thermal denaturation at various temperatures 53–63 °C were also determined. The half -life of SAI at 53 and 63 °C was 112 and 10 min, respectively. At 55 °C, surprisingly the half -life increased to twice that at 53 °C. ΔG*, ΔH* and ΔS* of irreversible thermal stability of SAI at 55 °C were 107.7 kJ mol?1, 276.04 kJ mol?1 and 513 J mol?1K?1, respectively.  相似文献   

18.
Lipoxygenase from olive fruit was purified to homogeneity for the first time after differential centrifugations and by hydrophobic chromatography. The enzyme had a molecular mass of 98 kDa and exhibited a maximal activity at pH 6. Lipoxygenase had a better affinity for linoleic acid (Km=82.44 microM) than for linolenic acid (Km = 306.26 microM). It is inhibited by linoleate:oxygen oxidoreductase (LOX) inhibitors like nordihydroguaiaretic acid (NDGA) or propyl gallate. The reaction product was 13-hydroperoxy octadecadienoic acid when linoleic acid was used as substrate.  相似文献   

19.
The phytopathogenic fungus Botrytis cinerea produces a set of polygalacturonases (PGs) which are involved in the enzymatic degradation of pectin during plant tissue infection. Two polygalacturonases secreted by B. cinerea in seven-day-old liquid culture were purified to apparent homogeneity by chromatography. PG I was an exopolygalacturonase of molecular weight 65 kDa and pI 8.0 and PG II was an endopolygalacturonase of 52 kDa and pI 7.8. Enzymatic activity of PG I and PG II was partially inhibited by 1 mM CaCl2, probably by calcium chelation of polygalacturonic acid, the substrate of the enzyme.  相似文献   

20.
Lactobacillus plantarum produced extracellular polygalacturonase in a medium containing 1.5% low methyl-pectin (w/v) and 0.5% glucose (w/v) as inducers. The enzyme was purified (approximately 70-fold) by ammonium sulphate fractionation, Sephadex G-100 gel filtration and DEAE-cellulose ion exchange chromatography. Two peaks (PG I and PG II) of enzymic activity were obtained from the DEAE-cellulose column. The molecular mass of PG I was similar to that of PG II (32 000 Da). The K m values of PG I and PG II for sodium polypectate were calculated to be 1.63 mg/ml and 1.78 mg/ml respectively. Their isoelectric points were about pH 5.5. The pH optimum was 4.5, while the optimum temperature was 35°C for both PG I and PG II. The two purified enzymes had similar endo modes of action on polygalacturonic acid, as determined by comparison of viscosity reduction and reducing group release.  相似文献   

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