Effect of culture conditions on the biomass determination by ergosterol of <Emphasis Type="Italic">Lentinus crinitus</Emphasis> and <Emphasis Type="Italic">Psilocybe castanella</Emphasis>

Estimating fungal growth is important in processes of soil bioremediation. It has been demonstrated that ergosterol is a good indicator of fungal biomass in solid substrata. In the present study were evaluated the effects upon the ergosterol rate of Lentinus crinitus Berk. and Psilocybe castanella Peck through the culture conditions of these fungi, which are evaluated for the bioremediation of soils contaminated by organochlorates. A good correlation between fungal biomass and ergosterol was observed for both species. The culture conditions did not influence the ergosterol rate of L. crinitus. Yet the ergosterol rate of P. castanella was influenced from 35 days of culture and when grown in the presence of 15.00 g hexachlorobenzene l⁻¹ of culture medium. So it is possible to estimate growth of both species using ergosterol as indicator in processes of soil bioremediation since the influences observed in the ergosterol rate of P. castanella are considered.     

Production of withanolide-A from adventitious root cultures of Withania somnifera

Withanolides are biologically active secondary metabolites present in roots and leaves of Withania somnifera. In the present study, we have induced adventitious roots from leaf explants of W. somnifera for the production of withanolide-A, which is having pharmacological activities. Adventitious roots were induced directly from leaf segments of W. somnifera on half strength Murashige and Skoog (MS) semisolid medium (0.8% agar) with 0.5 mg l⁻¹ indole-3-butyric acid (IBA) and 30 g l⁻¹ sucrose. Adventitious roots cultured in flasks using half strength MS liquid medium with 0.5 mg l⁻¹ IBA and 30 g l⁻¹ showed higher accumulation of biomass (108.48 g l⁻¹FW and 10.76 g l⁻¹ DW) and withanolide-A content (8.8 ± 0.20 mg g⁻¹ DW) within five weeks. Nearly 11-fold increment of fresh biomass was evident in suspension cultures and adventitious root biomass produced in suspension cultures possessed 21-fold higher withanolide-A content when compared with the leaves of natural plants. An inoculum size of 10 g l⁻¹ FW favoured the biomass accumulation and withanolide-A production in the tested range of 2.5, 5.0, 10.0 and 20.0 g l⁻¹ FW. Among different media tested [Murashige and Skoog (MS), Gamborg’s (B5), Nitsch and Nitsch (NN) and Chu’s (N6)], MS medium favoured both biomass accumulation and withanolide-A production. Half strength MS medium favoured the biomass accumulation and withanolide-A production among the different strength MS medium tested (0.25, 0.5, 0.75, 1.0, 1.5 and 2.0). The current results showed great potentiality of adventitious roots cultures for the production of withanolide-A.     

Application of the white rot fungus <Emphasis Type="Italic">Phanerochaete chrysosporium</Emphasis> in biotreatment of bagasse effluent

Biotreatment of bagasse effluent using Phanerochaete chrysosporium (white rot fungus) is investigated. This study confirmed that lignin is the major pollutant component in this effluent followed by different carbohydrates. The treatment conditions must be very proper, especially in terms of biomass culture to achieve a successful treatment. The best conditions of temperature, biomass concentration, pH and duration for biotreatment of this effluent were 35°C, 552 mg l⁻¹, 6 and 5 to 9 days, respectively. Under these conditions, a 9 days long treatment reduced by 98.7% the original biochemical oxygen demand (of 2,780 mg l⁻¹) and by 98.5% the dissolved chemical oxygen demand (initial 4,200 mg l⁻¹). Moreover, fungal treatment reduced total dissolved solids from 3,950 to 575 mg l⁻¹ and color from 560 mg l⁻¹ PtCo to 111 mg l⁻¹ PtCo.     

Estimation of fungal biomass in the decaying cones ofPinus densiflora

Fungal biomass in the decaying cones ofPinus densiflora was investigated. Leaching, immobilization and mobilization phases were recognized in the decomposition process of cones. Fungal biomass was estimated by the agar-film technique, using a conversion factor of 0.62 mg dry wt. mm⁻³ of hyphal volume to biomass and a factor of 2.5 for in-efficiencency of homogenization. The fungal biomass was 4.9±2.1 (mean±S.D.) mg dry wt. g⁻¹ dry matter in the cones on the tree, 11±6 mg g⁻¹ in the leaching phase, 19±7 mg g⁻¹ in the immobilization phase and 30±15 mg g⁻¹ in the mobilization phase. It significantly increased after cones had lain on the forest floor, and also in the immobilization phase. The latter result suggests that the fungal biomass contributed to the immobilization of nitrogen in the decomposition process. The ratio of ergosterol content to fungal biomass in the cones was 2.9–8.8 μg mg⁻¹ dry wt., lying in the range of 2–16 μg mg⁻¹ reported for mycelia. This suggested that the estimate of fungal biomass was reasonable. Reduction in this ratio with the dry weight loss in the cones suggested that the proportion of relatively active fungal biomass decreased with the progress of decomposition.     

Fungal biomass associated with decaying leaf litter in a stream

Summary Fungal biomass, measured as ergosterol content, was determined on alder leaf litter incubated during autumn in a softwater Pyrenean stream. The ergosterol content of the leaf litter increased rapidly to a maximum of 462 μg/g detrital dry mass. Ergosterol contents of aquatic Hyphomycetes grown in shake culture were typically ≤5 mg/g mycelial dry mass. Using the corresponding ergosterol-to-biomass conversion factor of 200, peak fungal mass accounted for 9.2% of total system mass, or 10.2% of leaf dry mass. For the period of highest activity (incubation days 7–28), net fungal production on leaf litter was estimated as 2.3 mg d⁻¹ g⁻¹ leaf mass. A conservative estimate of the growth efficiency for the same period was 105 mg mycelial mass per gram leaf mass degraded, assuming that non-leaf organic matter did not constitute an important carbon source supporting fungal production.     

Decolorization of Acid red 151 by Aspergillus niger SA1 under different physicochemical conditions

The fungal strain A. niger SA1 isolated from textile wastewater pond proved to be an important source of remediation (decolorization/degradation) for textile dye, AR 151 (Reactive diazo dye) under different physicochemical conditions. Decolorization assays of AR 151 were carried out in Simulated textile effluent under shake flask condition for 8 days. Decolorization (at 20 mg l⁻¹ of dye) and related biomass production overall decreased with increase in pH from 5 to 9, at 30°C. It was maximum (95.71%) at pH 5 with highest amount of three residual products (36.91 (α-naphthol = 5.72) (sulfanilic acid = 24.81) (aniline = 6.38)) besides 2.05 mg ml⁻¹ of biomass production at an optimum concentration 6 and 0.1 mg l⁻¹ of glucose and urea respectively. The formation of the three products followed a quite different pattern at different pH values, however, it was considerably low (Total = 2.81 mg l⁻¹) compared to the amount of decolorization (67.26%) at pH 8. Decolorization (95–97%) was most favored under mesophilic temperature (25–45°C). It increased i.e., 90–98% with subsequent increase in dye from 10 to 100 mg l⁻¹, kept ≥50% below 400 mg l⁻¹ and drastically declined to 17% at 500 mg l⁻¹ of dye. Apparently, decolorization is found to be associated with fungal growth and hyphal uptake mechanism (Biosorption/Bioadsorption), however, mineralization of AR 151 and related products under different operational conditions also suggested a metabolically mediated decolorization/degradation.     

Decolorization of structurally different textile dyes by Aspergillus niger SA1

The fungal strain, Aspergillus niger SA1, isolated from textile wastewater sludge was screened for its decolorization ability for four different textile dyes. It was initially adapted to higher concentration of dyes (10–1,000 mg l⁻¹) on solid culture medium after repeated sub-culturing. Maximum resistant level (mg l⁻¹) sustained by fungal strain against four dyes was in order of; Acid red 151 (850) > Orange II (650) > Drimarene blue K₂RL (550) > Sulfur black (500). The apparent dye removal for dyes was seen largely due to biosorption/bioadsorption into/onto the fungal biomass. Decolorization of Acid red 151, Orange II, Sulfur black and Drimarine blue K₂RL was 68.64 and 66.72, 43.23 and 44.52, 21.74 and 28.18, 39.45 and 9.33% in two different liquid media under static condition, whereas, it was 67.26, 78.08, 45.83 and 13.74% with 1.40, 1.73, 5.16 and 1.87 mg l⁻¹ of biomass production under shaking conditions respectively in 8 days. The residual amount (mg l⁻¹) of the three products (α-naphthol, sulfanilic acid and aniline) kept quite low i.e., ≤2 in case AR 151 and Or II under shaking conditions. Results clearly elucidated the role of Aspergillus niger SA1 in decolorizing/degrading structurally different dyes into basic constituents.     

Ethrel treatment enhanced isoflavonoids accumulation in cell suspension cultures of Pueraria tuberosa, a woody legume

The cell cultures of Pueraria tuberosa, a perennial leguminous lianas, were maintained in modified MS medium (KNO₃ 475 mg l⁻¹, thiamine 1 mg l⁻¹, biotin 1 mg l⁻¹, calcium pantothenate 1 mg l⁻¹) containing 0.1 mg l⁻¹ 2,4,5-trichloroacetic acid and 0.1 mg l⁻¹ kinetin. Isoflavonoids (puerarin, genistin, daidzein, genistein) accumulation in cell suspension cultures was increased by 14-fold to ~12 mg l⁻¹ after 48 h of adding 100 μM ethrel. Ethrel inhibitors (silver nitrate and silver thiosulfate) completely inhibited this effect in the presence of ethrel and isoflavonoids were not detected in the spent medium. The increase was dose dependent and can be explored to trigger high yield of isoflavonoids production.     

The morphological and physiological evolution of <Emphasis Type="Italic">Aspergillus terreus</Emphasis> mycelium in the submerged culture and its relation to the formation of secondary metabolites

The influence of the morphology and differentiation of Aspergillus terreus hyphae on the formation of mevinolinic acid (lovastatin) and (+)-geodin was tested. Lovastatin titre was the highest (above 60 mg l⁻¹) in the system with smaller pellets (diameter below 1.5 mm) and high biomass concentration (above 10 g l⁻¹ in the idiophase). These biomass features were induced by the higher initial number of spores in the preculture (above 2 × 10¹⁰ l⁻¹). At the initial number of spores below 2 × 10⁹ l⁻¹ (+)-geodin biosynthesis was the most efficient but it was rather connected with the elevated C/N ratio than with the pellet size. In order to quantify the hyphal differentiation in fungal pellets a special approach was used. The sectioning of the stained pellets together with the image analysis and calculation procedures were applied. The analysis of hyphal differentiation indicated that lovastatin formation was correlated with the fraction of the active, growing hyphae.     

Asparagus racemosus cell cultures: a source for enhanced production of shatavarins and sarsapogenin

Asparagus racemosus is an important monocot medicinal plant that is in great demand for its steroidal saponins called shatavarins. This study was initiated to optimize the conditions for production of shatavarins in cell cultures of A. racemosus in a modified Murashige and Skoog (MS) medium supplemented with six different combinations of growth regulators. Biomass accumulation was correlated with saponin production over a 30-d culture cycle. Biomass and saponin accumulation patterns were dependent on combinations of growth regulators and the pH of the medium. Maximum levels of saponin and biomass accumulation were recorded on day 25 of the culture cycle within a pH range of 3.4 to 5.6. Total saponin produced by the in vitro cultures was 20-fold higher than amounts produced by cultivated plants. Saponin accumulation was not a biomass-associated phenomenon; cultures which showed the highest biomass accumulation were not the highest saponin accumulators. Maximum biomass (28.30 ± 0.29 g l⁻¹) and maximum levels of shatavarin IV(11.48 ± 0.61 mg g⁻¹) accumulation was found using a medium containing 2.0 mg l⁻¹ 2,4-D, 2 g l⁻¹ casein hydrolysate and 0.005% pectinase. The highest levels of sarsapogenin, secreted and intracellular (4.02 ± 0.09 mg g⁻¹), accumulated using a medium containing 1.0 mg l⁻¹ NAA, 1.0 mg l⁻¹ 2,4-D, 0.5 mg l⁻¹ BAP, 2 g l⁻¹ casein hydrolysate and 0.005% pectinase, after 25 d. Shatavarins were secreted into the medium and can be isolated easily for further purification.     

Selection of vinasse degrading microorganisms

Vinasse is a highly colored effluent with a high pollutant potential when disposed in the environment. Assays for decolorization of vinasse were performed, selecting the fungus Pleurotus sajor-caju CCB 020. The discoloration was cocominant with the increase of the activities of laccase, manganese-peroxidase and peroxidases. P. sajor-caju demonstrated a rise in biomass production (1.06 g 100 ml⁻¹), and the enzyme activities such as laccase (varying from 400 to 450 IU l⁻¹) reached between the 9th and 10th day of growth and for MnP at the 12th day of cultivation (varying from 60 to 100 IU l⁻¹). It was concluded that the system P. sajor-caju/vinasse can be utilized as a bioprocess for color removal and degradation of complex vinasse compounds. It was observed an improvement in the characteristics and detoxification allowing its utilization as reused water, laccase and manganese-peroxidase enzymes production and for fungal biomass production with a high nutritional value.     

Statistical medium optimization for enhanced azadirachtin production in hairy root culture of Azadirachta indica

Azadirachtin, a well-known biopesticide, is a secondary metabolite extracted from the seeds of Azadirachta indica. In the present study, azadirachtin was produced in hairy roots of A. indica, generated by Agrobacterium rhizogenes-mediated transformation of leaf explants. Liquid cultures of A. indica hairy roots were developed with a liquid-to-flask volume ratio of 0.15. The kinetics of growth and azadirachtin production were established in a basal plant growth medium containing MS medium major and minor salts, Gamborg’s medium vitamins, and 30 g l⁻¹ sucrose. The highest azadirachtin accumulation in the hairy roots (up to 3.3 mg g⁻¹) and azadirachtin production (∼44 mg l⁻¹) was obtained on Day 25 of the growth cycle, with a biomass production of 13.3 g l⁻¹ dry weight. To enhance the production of azadirachtin, a Plackett–Burman experimental design protocol was used to identify key medium nutrients and concentrations to support high root biomass production and azadirachtin accumulation in hairy roots. The optimal nutrients and concentrations were as follows: 40 g l⁻¹ sucrose, 0.19 g l⁻¹ potassium dihydrogen phosphate, 3.1 g l⁻¹ potassium nitrate, and 0.41 g l⁻¹ magnesium sulfate. Concentrations were determined by a central composite design protocol and verified in shake-flask cultivation. The optimized medium composition yielded a root biomass production of 14.2 g l⁻¹ and azadirachtin accumulation of 5.2 mg g⁻¹, which was equivalent to an overall azadirachtin production of 73.84 mg l⁻¹, 68% more than that obtained under non-optimized conditions.     

Role of ethylene and jasmonic acid on rhizome induction and growth in rhubarb (<Emphasis Type="Italic">Rheum rhabarbarum</Emphasis> L.)

Experiments were conducted to elucidate the hormonal induction and regulation of rhizome growth in rhubarb (Rheum rhabarbarum L.). It was found that ethylene is the key regulator of rhizome induction and development. The role of jasmonic acid (JA) and its interaction with ethylene in rhizome induction and growth were also examined. Both ethylene and JA have a significant effect on promoting rhizome formation in vitro. Conversely, the ethylene biosynthesis inhibitor aminoethoxyvinylglycine (AVG) (1.5 μM) inhibited rhizome induction in multiple-shoot clumps in vitro, and suppressed the stimulatory effects of exogenously applied ethephon (1 mg l⁻¹) and JA (10 ng l⁻¹) in promoting mini-rhizome formation, further confirming the role of endogenous ethylene in the process. In addition, rhizome growth was significantly enhanced in the presence of both ethylene and JA (ethephon 1 mg l⁻¹ and JA 10 ng l⁻¹) compared to JA alone. These results suggest that endogenous ethylene is the key regulator of rhizome growth in rhubarb and JA promotes rhizome formation, possibly through inducing endogenous ethylene synthesis.     

Repeated Batch Cultivation of Ralstonia eutropha for Poly (β-hydroxybutyrate) Production

Batch cultivation of Ralstonia eutropha NRRL B14690 attained 21 g biomass l⁻¹ and 9.4 g poly(β-hydroxybutyrate) l⁻¹ (0.45 g PHB g⁻¹ dry wt⁻¹) in 60 h. Repeated batch operation (empty-and-fill protocol) to remove 20% (v/v) of the culture broth and to supplement an equal volume of fresh media resulted in 49 g biomass l⁻¹ and 25 g PHB l⁻¹ (0.51 g PHB g⁻¹ dry wt⁻¹) with an overall productivity of 0.42 g PHB l⁻¹ h⁻¹ in 67 h. In the two cycles of repeated batch fermentation there was a 3-fold increase in productivity as compared to batch.     

Improved guggulsterone production from sugars, precursors, and morphactin in cell cultures of Commiphora wightii grown in shake flasks and a bioreactor

Cell cultures of Commiphora wightii (Arnott.) Bhandari were grown in shake flasks and a bioreactor and an increase in guggulsterone accumulation up to 18 μg l⁻¹ was recorded in cells grown in the production medium containing a combination of sucrose:glucose (4% total), precursors (phenylalanine, pyruvic acid, xylose, and sodium acetate), morphactin, and 2iP. A yield of 10 g l⁻¹ biomass and ∼200 μg l⁻¹ guggulsterone was recorded in a 3-l flask and in a 2-l stirred tank bioreactor compared with 6.6 g biomass and 67 μg l⁻¹ guggulsterone in 250-ml flasks. Increased vessel size was correlated with increased biomass and guggulsterone accumulation. 2iP alone was not effective for biomass and guggulsterone accumulation in cell cultures of C. wightii.     

The Estimated Impact of Fungi on Nutrient Dynamics During Decomposition of Phragmites australis Leaf Sheaths and Stems

Decomposition of culms (sheaths and stems) of the emergent macrophyte Phragmites australis (common reed) was followed for 16 months in the litter layer of a brackish tidal marsh along the river Scheldt (the Netherlands). Stems and leaf sheaths were separately analyzed for mass loss, litter-associated fungal biomass (ergosterol), nutrient (N and P), and cell wall polymer concentrations (cellulose and lignin). The role of fungal biomass in litter nutrient dynamics was evaluated by estimating nutrient incorporation within the living fungal mass. After 1 year of standing stem decay, substantial fungal colonization was found. This corresponded to an overall fungal biomass of 49 ± 8.7 mg g⁻¹ dry mass. A vertical pattern of fungal colonization on stems in the canopy is suggested. The litter bag experiment showed that mass loss of stems was negligible during the first 6 months, whereas leaf sheaths lost almost 50% of their initial mass during that time. Exponential breakdown rates were −0.0039 ± 0.0004 and −0.0026 ± 0.0003 day⁻¹ for leaf sheaths and stems, respectively (excluding the initial lag period). In contrast to the stem tissue—which had no fungal colonization—leaf sheaths were heavily colonized by fungi (93 ± 10 mg fungal biomass g⁻¹ dry mass) prior to placement in the litter layer. Once being on the sediment surface, 30% of leaf sheath's associated fungal biomass was lost, but ergosterol concentrations recovered the following months. In the stems, fungal biomass increased steadily after an initial lag period to reach a maximal biomass of about 120 mg fungal biomass g⁻¹ dry mass for both plant parts at the end of the experiment. Fungal colonizers are considered to contain an important fraction of nutrients within the decaying plant matter. Fungal N incorporation was estimated to be 64 ± 13 and 102 ± 15% of total available N pool during decomposition for leaf sheaths and stems, respectively. Fungal P incorporation was estimated to be 37 ± 9 and 52 ± 15% of total available P during decomposition for leaf sheaths and stems, respectively. Furthermore, within the stem tissue, fungi are suggested to be active immobilizers of nutrients from the external environment because fungi were often estimated to contain more than 100% of the original nutrient stock.     

A study on using fireclay as a biomass carrier in an activated sludge system

By adding a biomass carrier to an activated sludge system, the biomass concentration will increase, and subsequently the organic removal efficiency will be enhanced. In this study, the possibility of using excess sludge from ceramic and tile manufacturing plants as a biomass carrier was investigated. The aim of this study was to determine the effect of using fireclay as a biomass carrier on biomass concentration, organic removal and nitrification efficiency in an activated sludge system. Experiments were conducted by using a bench scale activated sludge system operating in batch and continuous modes. Artificial simulated wastewater was made by using recirculated water in a ceramic manufactutring plant. In the continuous mode, hydraulic detention time in the aeration reactor was 8 and 22 h. In the batch mode, aeration time was 8 and 16 h. Fireclay doses were 500, 1,400 and 2,250 mg l⁻¹, and were added to the reactors in each experiment separately. The reactor with added fireclay was called a Hybrid Biological Reactor (HBR). A reactor without added fireclay was used as a control. Efficiency parameters such as COD, MLVSS and nitrate were measured in the control and HBR reactors according to standard methods. The average concentration of biomass in the HBR reactor was greater than in the control reactor. The total biomass concentration in the HBR reactor (2.25 g l⁻¹ fireclay) in the continuous mode was 3,000 mg l⁻¹ and in the batch mode was 2,400 mg l⁻¹. The attached biomass concentration in the HBR reactor (2.25 g l⁻¹ fireclay) in the continuous mode was 1,500 mg l⁻¹ and in the batch mode was 980 mg l⁻¹. Efficiency for COD removal in the HBR and control reactor was 95 and 55%, respectively. In the HBR reactor, nitrification was enhanced, and the concentration of nitrate was increased by 80%. By increasing the fireclay dose, total and attached biomass was increased. By adding fireclay as a biomass carrier, the efficiency of an activated sludge system to treat wastewater from ceramic manufacturing plants was increased.     

The Green Microalga <Emphasis Type="Italic">Chlorella saccharophila</Emphasis> as a Suitable Source of Oil for Biodiesel Production

The aim of this study was to investigate the potential of the green microalga Chlorella saccharophila as a source of oil for biodiesel production. We evaluated for the first time, the effect of salinity and/or nitrogen depletion (ND) on cell growth, lipid accumulation and lipid profile in this microalga. The fatty acid methyl esters (FAME) identified for C. saccharophila in this study consisted of C-16:0, C-18:0, C-18:1 cis, and C-18:1 trans. Among these, C-18:1 (indicator of biodiesel quality) was the main FAME found, representing approximately 76 and 80% of total FAME under normal and ND growing conditions, respectively. Under a normal growing condition this microalga showed 154.63 mg l⁻¹ d⁻¹, 63.33 mg l⁻¹ d⁻¹, and 103.73 mg l⁻¹ of biomass productivity, lipid productivity, and FAME yield, respectively. The higher biomass productivity (159.58 mg l⁻¹ d⁻¹), lipid productivity (99.33 mg l⁻¹ d⁻¹), and FAME yield (315.53 mg l⁻¹) were obtained under the ND treatment. In comparison to other related studies, our results suggest that C. saccharophila can be considered as a suitable source of oil for biodiesel production.     

Microbial loop malfunctioning in the annual sea ice at Terra Nova Bay (Antarctica)

We investigated organic carbon quantity and biochemical composition, prokaryotic abundance, biomass and carbon production in the annual and platelet sea ice of Terra Nova Bay (Antarctica), as well as the downward fluxes of organic matter released by melting ice during early spring. Huge amounts of biopolymeric C accumulated in the bottom layer of the ice column concomitantly with the early spring increase in sympagic algal biomass. Such organic material, mostly accounted for by autotrophic biomass, was characterised by a high food quality and was rapidly exported to the sea bottom during sea ice melting. Prokaryote abundance (up to 1.3 × 10⁹ cells L⁻¹) and extracellular enzymatic activities (up to 24.3 μM h⁻¹ for amino-peptidase activity) were extremely high, indicating high rates of organic C degradation in the bottom sea ice. Despite this, prokaryote C production values were very low (range 5–30 ng C L⁻¹ h⁻¹), suggesting that most of the degraded organic C was not channelled into prokaryote biomass. In the platelet ice, we found similar organic C concentrations, prokaryote abundance and biomass values and even higher extracellular enzymatic activities, but values of prokaryote C production (range 800–4,200 ng C L⁻¹ h⁻¹) were up to three orders of magnitude higher than in the intact bottom sea ice. Additional field and laboratory experiments revealed that the dissolved organic material derived from algae accumulating in the bottom sea ice significantly reduced prokaryote C production, suggesting the presence of a potential allopathic control of sympagic algae on prokaryote growth. This article belongs to a special topic: Five articles on Sea-ice communities in Terra Nova Bay (Ross Sea), coordinated by L. Guglielmo and V. Saggiomo, appear in this issue of Polar Biology. The studies were conducted in the frame of the National Program of Research in Antarctica (PNRA) of Italy.     

Growth retardants stimulate guggulsterone production in the presence of fungal elicitor in fed-batch cultures of <Emphasis Type="Italic">Commiphora wightii</Emphasis>

Guggulsterone, a hypolipidemic natural agent, is produced in resin canals of the plant Commiphora wightii. In this study, the stimulatory effects of growth retardants [ALAR (N,N-dimethylaminosuccinamic acid) and CCC (chlormequat chloride)] and fungal elicitor on guggulsterone accumulation in cell cultures of C. wightii are reported. CCC at 1 mg l⁻¹ enhanced guggulsterone content (~123 μg l⁻¹) when added on the fifth day after inoculation, while ALAR at 2.5 mg l⁻¹ increased guggulsterone content (~116 μg l⁻¹) when added on the tenth day. In a two-stage fed-batch process, combined treatment with fungal elicitor and growth retardant caused a significant increase (~353 μg l⁻¹) in guggulsterone content in cell cultures after 17 days of growth. This represents an approximately fivefold increase over the guggulsterone contents in initial cultures of this plant.