Effect of multiple factors on accumulation of nucleosides and bases in Cordyceps militaris

Construction of a New Agrobacterium tumefaciens-Mediated Transformation System based on a Dual Auxotrophic Approach in Cordyceps militaris

Cordyceps militaris is a significant edible fungus that produces a variety of bioactive compounds. We have previously established a uridine/uracil auxotrophic mutant and a corresponding Agrobacterium tumefaciens-mediated transformation (ATMT) system for genetic characterization in C. militaris using pyrG as a screening marker. In this study, we constructed an ATMT system based on a dual pyrG and hisB auxotrophic mutant of C. militaris. Using the uridine/uracil auxotrophic mutant as the background and pyrG as a selection marker, the hisB gene encoding imidazole glycerophosphate dehydratase, required for histidine biosynthesis, was knocked out by homologous recombination to construct a histidine auxotrophic C. militaris mutant. Then, pyrG in the histidine auxotrophic mutant was deleted to construct a ΔpyrG ΔhisB dual auxotrophic mutant. Further, we established an ATMT transformation system based on the dual auxotrophic C. militaris by using GFP and DsRed as reporter genes. Finally, to demonstrate the application of this dual transformation system for studies of gene function, knock out and complementation of the photoreceptor gene CmWC-1 in the dual auxotrophic C. militaris were performed. The newly constructed ATMT system with histidine and uridine/uracil auxotrophic markers provides a promising tool for genetic modifications in the medicinal fungus C. militaris.

Enhanced production of cordycepin under solid-state fermentation of Cordyceps militaris by using combinations of grains/substrates

This manuscript deals with cordycepin, an interesting secondary compound produced from entomopathogenic fungus, Cordyceps. It has attracted commercial interest due to its immense pharmacological importance beneficial to human health. In this study, the contents of cordycepin and its derivatives, like adenine and adenosine, were evaluated through solid-state fermentation using combinations of various grains as substrate. Treatment with grain combination numbers 2, 7, 8, and 9 exhibited higher cordycepin content (1.621, 1.929, 1.895, and 1.996 mg/g cordycepin, respectively) than control (rice). The grain combination number 7 exhibited significantly higher adenine content (700 mg/g) than the control and all other combinations. Treatments with grain combination numbers 2, 5, and 7 exhibited higher adenosine content (2.719, 2.938, and 3.392 mg/g, respectively); however, no significant increase in adenosine content was noted in any treatments. The biomass including fresh mycelium and fruit body was found higher in grain combination numbers 7 and 9, leading to enhanced cordycepin content. Overall, the increase in the fresh biomass significantly enhanced cordycepin accumulation. The level of cordycepin was recorded as higher than that of its derivatives, adenosine and adenine. The grain combination of rice, wheat, jowar, bajra, and sugarcane bagasse added to basal medium exhibited the highest cordycepin content and was found suitable for solid-state fermentation of Cordyceps militaris. To our understanding, the present study is the first to use combinations of cereals for the production of cordycepin from C. militaris.

Bioactive compounds from Cordyceps and their therapeutic potential

The Clavicipitaceae family's largest and most diverse genus is Cordyceps. They are most abundant and diverse in humid temperate and tropical forests and have a wide distribution in: Europe, North America, and East and Southeast Asian countries, particularly: Bhutan, China, Japan, Nepal, Korea, Thailand, Vietnam, Tibet, and the Himalayan region of India, and Sikkim. It is a well-known parasitic fungus that feeds on insects and other arthropods belonging to 10 different orders. Over 200 bioactive metabolites, that include: nucleotides and nucleosides, polysaccharides, proteins, polypeptides, amino acids, sterols, and fatty acids, among others have been extracted from Cordyceps spp. demonstrating the phytochemical richness of this genus. These components have been associated with a variety of pharmacological effects, including: anti-microbial, anti-apoptotic, anti-cancer, anti-inflammatory, antioxidant, and immunomodulatory activities. In this paper, the bioactivity of various classes of metabolites produced by Cordyceps spp., and their therapeutic properties have been reviewed in an attempt to update the existing literature. Furthermore, one of its nucleoside and a key bioactive compound, cordycepin has been critically elaborated with regard to its biosynthesis pathway and the recently proposed protector-protégé mechanism as well as various biological and pharmacological effects, such as: suppression of purine and nucleic acid biosynthesis, induction of apoptosis, and cell cycle regulation with their mechanism of action. This review provides current knowledge on the bioactive potential of Cordyceps spp.

CmLec4, a lectin from the fungus Cordyceps militaris, controls host infection and fruiting body formation

Fungi belonging to the Ascomycete genus Cordyceps are endoparasitoids and parasites, mainly of insects and other arthropods. Cordyceps militaris has been used as a therapeutic drug for cancer patients. However, the infection, parasitism, and fruiting body formation mechanisms of this fungus are still unknown. Based on our hypothesis that lectin(s) is involved in the interaction between the C. militaris fungi and insects, we partially purified and characterized a new lectin from C. militaris, designated CmLec4. In addition, we searched for substance(s) in the infected silkworm extracts that could bind to CmLec4, and succeeded in purifying the sex-specific storage protein 2 as a specific binding target. To examine function of the binding protein during the process of parasitism, we investigated the effect of recombinant CmLec4 on silkworms by inoculating the protein into silkworm pupae, and found that it significantly delayed emergence compared to the control. Furthermore, cmlec4 gene knockout strains constructed in this study produced markedly lower amounts of fruiting body than the wild-type strain. All the results revealed that the lectin CmLec4 produced by C. militaris would be involved in the infection into silkworm and fruiting body formation from the host.

Improvement in the Blood Urea Nitrogen and Serum Creatinine Using New Cultivation of Cordyceps militaris

Background

Chronic kidney disease (CKD) is a critical public health issue with a huge financial burden for both patients and society worldwide. Unfortunately, there are currently no efficacious therapies to prevent or delay the progression of end-stage renal disease (ESRD). Traditional Chinese medicine practices have shown that Cordyceps militaris (C. militaris) mycelia have a variety of pharmacologically useful properties, including antitumor, immunomodulation, and hepatoprotection. However, the effect of mycelial C. militaris on CKD remains unclear.

Methods

Here, we investigated the effects of C. militaris mycelia on mice with CKD using four types of media: HKS, HKS with vitamin A (HKS + A), CM, and CM with vitamin A (CM + A).

Results

The results at day 10 revealed that the levels of blood urea nitrogen (BUN) were significantly lower in the HKS (41%), HKS + A (41%), and CM + A (34%) groups compared with those in the corresponding control groups (nephrectomic mice). The level of serum creatinine in the HKS + A group decreased by 35% at day 10, whereas the levels in the HKS and CM + A groups decreased only by 14% and 13%, respectively, on day 30. Taken together, this is the first report using four new media (HKS, HKS + A, CM, and CM + A medium) for C. militaris mycelia. Each medium of mycelial C. militaris on CKD exhibits specific effect on BUN, serum creatinine, body weight, total protein, and uric acid.

Conclusions

Taken together, this is the first report using four new media (HKS, HKS + A, CM, and CM + A medium) for C. militaris mycelia. Each medium of mycelial C. militaris on CKD exhibits specific effects on BUN, serum creatinine, body weight, total protein, and uric acid. We concluded that treatment with C. militaris mycelia cultured in HKS or CM + A medium could potentially prevent the deterioration of kidney function in mice with CKD.

Identification of Ophiocordyceps gracilioides by Its Anti-tumor Effects through Targeting the NFκB-STAT3-IL-6 Inflammatory Pathway

Although more than 400 species of Cordyceps s.l. have been identified, most have not been well explored regarding their potential for medicinal use. In this study, the profiles of constituents of ten different species of Ophiocordyceps, which is an unexplored species of Cordyceps, were analyzed and their anti-tumor effects were further examined. Although all Ophiocordyceps samples exhibited similar peak patterns, Ophiocordyceps gracilioides (O. grac) had a distinct constituent profile from the other samples. Furthermore, O. grac was the most active in suppressing the transcriptional activities of both nuclear factor-kappa B (NF-κB) and signal transducer and activator of transcription (STAT)3, and the production of interleukin (IL)-6 from breast cancer cells. This study demonstrated that O. grac is a relatively unexplored Cordyceps s.l. that may have medicinal potential to inhibit the NFκB-STAT3-IL-6 inflammatory pathway in cancer.

Cordycepin for Health and Wellbeing: A Potent Bioactive Metabolite of an Entomopathogenic Cordyceps Medicinal Fungus and Its Nutraceutical and Therapeutic Potential

Cordyceps is a rare naturally occurring entomopathogenic fungus usually found at high altitudes on the Himalayan plateau and a well-known medicinal mushroom in traditional Chinese medicine. Cordyceps contains various bioactive components, out of which, cordycepin is considered most vital, due to its utmost therapeutic as well as nutraceutical potential. Moreover, the structure similarity of cordycepin with adenosine makes it an important bioactive component, with difference of only hydroxyl group, lacking in the 3′ position of its ribose moiety. Cordycepin is known for various nutraceutical and therapeutic potential, such as anti-diabetic, anti-hyperlipidemia, anti-fungal, anti-inflammatory, immunomodulatory, antioxidant, anti-aging, anticancer, antiviral, hepato-protective, hypo-sexuality, cardiovascular diseases, antimalarial, anti-osteoporotic, anti-arthritic, cosmeceutical etc. which makes it a most valuable medicinal mushroom for helping in maintaining good health. In this review, effort has been made to bring altogether the possible wide range of cordycepin’s nutraceutical potential along with its pharmacological actions and possible mechanism. Additionally, it also summarizes the details of cordycepin based nutraceuticals predominantly available in the market with expected global value. Moreover, this review will attract the attention of food scientists, nutritionists, pharmaceutical and food industries to improve the use of bioactive molecule cordycepin for nutraceutical purposes with commercialization to aid and promote healthy lifestyle, wellness and wellbeing.

Transcriptome Analysis Reveals the Flexibility of Cordycepin Network in Cordyceps militaris Activated by L-Alanine Addition

Cordycepin, isolated from the traditional medicinal fungus Cordyceps militaris, has gained much attention due to its various clinical functions. Previous reports of L-alanine addition could significantly improve cordycepin production, but the molecular mechanism remains unknown. In this study, transcriptome analysis of C. militaris with doubled cordycepin production induced by L-alanine addition provides an insight into the flexibility of the cordycepin network. The biopathways of energy generation and amino acid conversion were activated so that cordycepin substrate generation was consequently improved. Specific genes of rate-limiting enzymes in these pathways, as well as related transcription factors, were figured out. Two key Zn2Cys6-type transcription factors CmTf1 and CmTf2 were verified to play the roles of doubling the cordycepin production by overexpression of their coding genes in C. militaris wild type. These results provide a complete map of the cordycepin network in C. militaris with a distinct understanding of the flexibility of joints, giving a better foundation for increasing cordycepin yield and strain breeding in the future.

Green synthesis of gold nanoparticles using a Cordyceps militaris extract and their antiproliferative effect in liver cancer cells (HepG2)

Hepatocellular carcinoma is the most common liver cancer among different types of cancers. Cordyceps Militaris mushroom species traditionally used as an alternative medicine in china for centuries. Gold nanoparticles plays vital role in the development of the anticancer drugs. In our research, we investigated the gold nanoparticles with C. Militaris on the hepatocellular carcinoma HepG2 cells. The synthesized gold nanoparticles stability and integrity was studied at different time intervals. The gold nanoparticles potentially halt the growth of the HepG2 cells at the IC50 concentration between 10 μg and 12.5 μg/ml. The HR-TEM and XRD revealed the size and shape of the synthesized gold nanoparticles. The size of the gold nanoparticles was about 15 20 nm and the shape of gold nanoparticles was face-center-cubic structure. The FT-IR results proved that the gold nanoparticles contain hydroxyl and alkynes groups. The gold nanoparticles extract develops ROS and cause damage to the mitochondrial membrane potential in the hepatocellular carcinoma HepG2 cells. The gold nanoparticles extract tends to initiate the apoptosis by activating the Bax, Bid, caspases and inhibits the activation anti-apoptotic bcl-2 in the HepG2 cells. Our results concluded that the gold nanoparticles with C. Militaris would be an efficient chemotherapeutic drug against the hepatocellular carcinoma cells.

Metabolomic comparison between wild Ophiocordyceps sinensis and artificial cultured Cordyceps militaris

A systematic study on the metabolome differences between wild Ophiocordyceps sinensis and artificial cultured Cordyceps militaris was conducted using liquid chromatography-mass spectrometry. Principal component analysis and orthogonal projection on latent structure-discriminant analysis results showed that C. militaris grown on solid rice medium (R-CM) and C. militaris grown on tussah pupa (T-CM) evidently separated and individually separated from wild O. sinensis, indicating metabolome difference among wild O. sinensis, R-CM and T-CM. The metabolome differences between R-CM and T-CM indicated that C. militaris could accommodate to culture medium by differential metabolic regulation. Hierarchical clustering analysis was further performed to cluster the differential metabolites and samples based on their metabolic similarity. The higher content of amino acids (pyroglutamic acid, glutamic acid, histidine, phenylalanine and arginine), unsaturated fatty acid (linolenic acid and linoleic acid), peptides, mannitol, adenosine and succinoadenosine in O. sinensis make it as an excellent choice as a traditional Chinese medicine for invigoration or nutritional supplementation. Similar compositions with O. sinensis and easy cultivation make artificially cultured C. militaris a possible alternative to O. sinensis.

Anticancer Efficacy of Cordyceps militaris Ethanol Extract in a Xenografted Leukemia Model

Cordyceps militaris is used widely as a traditional medicine in East Asia. Although a few studies have attempted to elucidate the anticancer activities of C. militaris, the precise mechanism of C. militaris therapeutic effects is not fully understood. We examined the anticancer activities of C. militaris ethanolic extract (Cm-EE) and its cellular and molecular mechanisms. For this purpose, a xenograft mouse model bearing murine T cell lymphoma (RMA) cell-derived cancers was established to investigate in vivo anticancer mechanisms. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, immunoblotting analysis, and flow cytometric assay were employed to check in vitro cytotoxicity, molecular targets, and proapoptotic action of Cm-EE. Interestingly, cancer sizes and mass were reduced in a C. militaris-administered group. Levels of the phosphorylated forms of p85 and AKT were clearly decreased in the group administered with Cm-EE. This result indicated that levels of phosphoglycogen synthase kinase 3β (p-GSK3β) and cleaved caspase-3 were increased with orally administered Cm-EE. In addition, Cm-EE directly inhibited the viability of cultured RMA cells and C6 glioma cells. The number of proapoptotic cells was significantly increased in a Cm-EE treated group compared with a control group. Our results suggested that C. militaris might be able to inhibit cancer growth through regulation of p85/AKT-dependent or GSK3β-related caspase-3-dependent apoptosis.

Evaluation of anti-fatigue property of the extruded product of cereal grains mixed with Cordyceps militaris on mice

BACKGROUND

Fatigue is a biological phenomenon that involves a feeling of extreme physical or mental tiredness that could potentially cause some severe chronic diseases. Recently, diet therapy has provided a new alternative to alleviate physical fatigue. In our previous study, addition of Cordyceps militaris (C. militaris) into an extruded product was shown to provide high nutrition and unique flavors; however, little is known whether this product has some scientific evidence regarding anti-fatigue property. The purpose of this study was to evaluate the anti-fatigue effects of extruded products of cereal grains (EC) and EC mixed with C. militaris (ECC).

METHODS

The mice were divided into seven groups: one group received distilled water (Control group, n = 20), and the other groups received different dosages of EC (5, 10 and 20 g/kg body weight, n = 20 per group) or of ECC (5, 10 and 20 g/kg body weight, n = 20 per group) solution in water. All of the mice were administered with distilled water, EC or ECC continuously for 30 days by gavage and the anti-fatigue activity was evaluated using a weight-loaded swimming test, along with assessments of fatigue-related indicators. The mode of fighting fatigue was investigated by determining changes in exercise endurance and biochemical markers, including exhaustive swimming time, lactate dehydrogenase (LDH), blood lactic acid (BLA), creatine kinase (CK), blood urea nitrogen (BUN), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT), and hepatic and muscle glycogen levels.

RESULTS

EC and ECC prolonged the swimming endurance time of mice compared to the control. The content of BLA at high dose of ECC group (20 g/kg) was significantly lower than that in the negative control group. CK, BUN and MDA levels were significantly reduced by treatment with EC and ECC compared to the negative control, while the low and middle dose of EC had no significant effect on MDA levels. Additionally, only the middle and high dose of EC (10, 20 g/kg) could significantly decrease the BUN level. EC and ECC treatments increased glycogen, LDH, SOD, CAT and GSH-Px levels. Low and middle dose of EC had no significant effects on muscle glycogen. Moreover, low dose of EC could increase the level of SOD but it was not statistically significant. Compared to the EC treatment groups, ECC demonstrated the efficacy of anti-fatigue potential, particularly at a high dose of ECC, the best performance in relieving fatigue.

CONCLUSIONS

These results suggest that EC and ECC could prevent exercise-induced fatigue in mice and ECC provided a better effect. In addition, C. militaris in ECC might play a crucial role in the anti-fatigue activity of ECC.

MHP-1 inhibits cancer metastasis and restores topotecan sensitivity via regulating epithelial-mesenchymal transition and TGF-β signaling in human breast cancer cells

BACKGROUND

Cordyceps has long been used to treat cancer. However, its pharmacologically active components as well as the molecular mechanisms underlying its effects are still unclear.

PURPOSE

To investigate the effect of MHP-1, a newly isolated polysaccharide from Mortierella hepialid (the asexual structure of C. sinensis), on breast cancer metastasis.

STUDY DESIGN

The effect of MHP-1 on breast cancer cell migration, epithelial-mesenchymal transition (EMT) and TGF-β signaling were investigated in vitro and in vivo. The effect of MHP-1 against topotecan-resistant MCF-7 cells that developed an EMT-like phenotype was also examined.

METHODS

The in vitro effect of MHP-1 on breast cancer cell proliferation and migration was evaluated by CCK8 and transwell assay. Morphological changes were observed and EMT markers were detected by western blot. The production of MMPs was measured by quantitative PCR and ELISA assay. To further investigate the mechanism that MHP-1 inhibited breast cancer EMT, western blot, ELISA, luciferase reporter gene assay, siRNA, quantitative PCR, immunohistochemistry, and xenograft tumor model were performed.

RESULTS

MHP-1 inhibited breast cancer cell migration but did not cause any cytotoxicity. MHP-1 significantly surpressed breast cancer EMT, and slightly decreased MMP-9 secretion. TGF-β signaling was selectively inhibited after MHP-1 treatment, and other EMT-related pathways, like Wnt and Notch, were not affected. MHP-1 reduced the secretion of TGF-β1, but rarely affected other EMT-induced cytokines. Dual luciferase assay and Smad2/3 phosphorylation analysis indicated that MHP-1 suppressed TGF-β signaling. We further showed that MHP-1 restored sensitivity in topotecan (TPT)-resistant MCF-7 cells that developed an EMT-like phenotype. Similarly, the effect of TPT on resistant MCF-7 cells was also increased either by ALK5 (TGFβRI) siRNA or by a small molecular inhibitor of ALK5, SB-431542. MHP-1 inhibited breast cancer metastasis in the MDA-MB-231 xenograft model, and the immunohistochemical staining showed dramatically decreased expression of ALK5 and vimentin, and increased expression of E-cadherin.

CONCLUSION

MHP-1 significantly inhibited breast cancer metastasis and restored drug sensitivity in TPT-resistant cells via down-regulation of TGF-β signaling and EMT program. The combination of non-toxic agents like MHP-1 and current anti-cancer drugs should be considered in the future treatment of cancer.

In vitro cytotoxic screening of 31 crude extracts of Thai herbs on a chondrosarcoma cell line and primary chondrocytes and apoptotic effects of selected extracts

Thirty-one dichloromethane and methanol crude extracts of 16 herb species used in Thai traditional folk medicine were studied for their cytotoxic activities on the SW 1353 chondrosarcoma cell line and primary chondrocytes. Methyl thiazolyl tetrazolium (MTT) cell viability assay and flow cytometric method were used as screening tools for cytotoxicity testing. The half maximal inhibitory concentration (IC50) was measured and reported for each crude extract. Apoptosis, necrosis, and cell viability were measured by flow cytometry at IC50. Two out of 31 herbal extracts, methanol extracts of Paris polyphylla var. chinensis and Ficus thailandica C.C. Berg & S. Gardner, showed potent anticancer activity. They demonstrated high apoptosis induction activity in SW 1353 cells but had less effect on percentage of viability and necrosis of normal chondrocyte cells. Cytotoxic screening and apoptosis assays suggest the potential anticancer activity of some plants used in Thai traditional medicine and provide information concerning their direct effects.

Cordyceps industry in China

Cordyceps, as a general term, describes a group of ascomycetous fungi growing on arthropods and other related fungi. Some cordyceps have been used in traditional Chinese medicine for centuries and cordyceps-derived products are currently a big industry in China. A number of medicinal and health products have been developed and extensively commercialized from natural Chinese cordyceps, its anamorphic fungus (Hirsutella sinensis), and other fungi known as Chinese cordyceps. The lack of a defined classification system for medicinal cordyceps fungi is a source of confusion in the industry and the public, and even among pharmaceutical scientists. This review summarizes the cordyceps fungi currently used in the industry in China with a special reference to clarify Chinese cordyceps and associated fungi. Cordyceps militaris, Cordyceps guangdongensis and Isaria cicadae are well recognized and commercialized cordyceps fungi in China. Except the natural Chinese cordyceps and its anamorphic fungus, Paecilomyces hepiali, Mortierella hepiali, Cephalosporium sinensis and Clonostachys rosea isolated from natural Chinese cordyceps are classified as Chinese cordyceps–associated fungi. P. hepiali is a cordyceps fungus based on current phylogenetic analysis of Hypocreales, while M. hepiali is a fungus in the Zygomycetes and should only be treated as associated fungus of Chinese cordyceps. C. sinensis and C. rosea belong to the Hypocreales and their relationship to cordyceps fungi should be further studied. The exploitation of the resources of cordyceps fungi and their quality control in the industry should be major topics for future studies. Cooperation between the industry and the research community will enhance the whole cordyceps industry.

Distribution of nucleosides in populations of Cordyceps cicadae

A rapid HPLC method had been developed and used for the simultaneous determination of 10 nucleosides (uracil, uridine, 2'-deoxyuridine, inosine, guanosine, thymidine, adenine, adenosine, 2'-deoxyadenosine and cordycepin) in 10 populations of Cordyceps cicadae, in order to compare four populations of Ophicordyceps sinensis and one population of Cordyceps militaris. Statistical analysis system (SAS) 8.1 was used to analyze the nucleoside data. The pattern of nucleoside distribution was analyzed in the sampled populations of C. cicadae, O. sinensis and C. militaris, using descriptive statistical analysis, nested analysis and Q cluster analysis. The total amount of the 10 nucleosides in coremium was 1,463.89–5,678.21 µg/g in 10 populations of C. cicadae, 1,369.80–3,941.64 µg/g in sclerotium. The average contents of the 10 analytes were 4,392.37 µg/g and 3,016.06 µg/g in coremium and sclerotium, respectively. The coefficient of variation (CV) of nucleosides ranged from 8.36% to 112.36% in coremium of C. cicadae, and from 10.77% to 155.87% in sclerotium of C. cicadae. The CV of the nucleosides was wide within C. cicadae populations. The nested variation analysis by the nine nucleosides’ distribution indicated that about 42.29% of the nucleoside variability in coremium was attributable to the differentiation among populations, and the remaining 57.71% resided in the populations. It was also shown that about 28.94% of the variation in sclerotium was expressed between populations, while most of the variation (71.06%) corresponded to the populations.

Pharmacological and therapeutic potential of Cordyceps with special reference to Cordycepin

An entomopathogenic fungus, Cordyceps sp. has been known to have numerous pharmacological and therapeutic implications, especially, in terms of human health making it a suitable candidate for ethno-pharmacological use. Main constituent of the extract derived from this fungus comprises a novel bio-metabolite called as Cordycepin (3′deoxyadenosine) which has a very potent anti-cancer, anti-oxidant and anti-inflammatory activities. The current review discusses about the broad spectrum potential of Cordycepin including biological and pharmacological actions in immunological, hepatic, renal, cardiovascular systems as well as an anti-cancer agent. The article also reviews the current efforts to delineate the mechanism of action of Cordycepin in various bio-molecular processes. The study will certainly draw the attention of scientific community to improve the bioactivity and production of Cordycepin for its commercial use in pharmacological and medical fields.

Comparison of culture methods on exopolysaccharide production in the submerged culture of Cordyceps militaris and process optimization

AIMS

To improve exopolysaccharides (EPS) production of Cordyceps militaris (C. militaris), effects of different culture method on mycelial biomass and EPS production in the submerged culture of C. militaris were investigated.

METHODS AND RESULTS

 A new two-stage fermentation process for EPS production of C. militaris was designed in this work. Central composite design (CCD) was utilized to optimize the two-stage fermentation process. The results showed that the two-stage fermentation process for EPS production was superior to other culture method (conventional static culture and shake culture). CCD revealed that the optimum values of the test variables for EPS production were shaken for 140 h followed by 130-h static culture. The maximum EPS production reached 3·2 g l(-1) under optimized two-stage culture and was about 2·3-fold and 1·6-fold in comparison with those of original static culture and shake culture.

CONCLUSIONS

It was indicated that a new two-stage culture method obtained in this work possessed a high potential for the industrial production for EPS of C. militaris.

SIGNIFICANCE AND IMPACT OF THE STUDY

The fundamental information obtained in this work is complementary to those of previous investigations on the submerged culture of C. militaris for the production of bioactive metabolites.

Medicinal uses of the mushroom Cordyceps militaris: current state and prospects

Cordyceps militaris is a potential harbour of bio-metabolites for herbal drugs and evidences are available about its applications for revitalization of various systems of the body from ancient times. Amongst all the species, C. militaris is considered as the oldest source of some useful chemical constituents. Besides their popular applications for tonic medicine by the all stairs of the community, the constituents of C. militaris are now used extensively in modern systems of medicine. The current survey records the mysterious potentials of C. militaris are boosting up the present herbal treatments, as well as gearing up the green pharmacy revolution, in order to create a friendly environment with reasonable safety. Evidence showed that the active principles of C. militaris are beneficial to act as pro-sexual, anti-inflammatory, anti-oxidant/anti-aging, anti-tumour/anti-cancer/anti-leukemic, anti-proliferative, anti-metastatic, immunomodulatory, anti-microbial, anti-bacterial, anti-viral, anti-fungal, anti-protozoal, insecticidal, larvicidal, anti-fibrotic, steroidogenic, hypoglacaemic, hypolipidaemic, anti-angiogenetic, anti-diabetic, anti-HIV, anti-malarial, anti-fatigue, neuroprotective, liver-protective, reno-protective as well as pneumo-protective, let alone their other synergistic activities, which let it be marketable in the western countries as over-the-counter medicine. A number of culture techniques for this mushroom have been noticed, for example, storage/stock culture, pre-culture, popular/indigenous culture (spawn culture, husked rice culture and saw dust culture) and, special/laboratory culture (shaking culture, submerged culture, surface liquid culture and continuous/repeated batch culture). The prospects for herbal biotechnology regarding drug discovery using C. militaris delivering what it has promised are high, as the technology is now extremely more powerful than before. This study chiefly highlights the medicinal uses of the mushroom C. militaris including its culture techniques, also aiming to draw sufficient attention of the researchers to the frontier research needs in this context.

Production of cordycepin and mycelia by submerged fermentation of Cordyceps militaris in mixture natural culture

The submerged fermentation of Cordyceps militaris for cordycepin production and mycelial growth was investigated in this study. Three natural materials of brown rice paste (BRP), beerwort (B), and soybean meal juice (SMJ) were used for fermentation of C. militaris in shaking flasks. The effects of the ratio of three natural materials on dry mycelium weight (DMW) and on cordycepin yield (CY) were analyzed. D-Optional mixture design was used to optimize the ratio of these materials. Compared with the signal culture, the higher mycelial growth and cordycepin production were obtained in mixture. The analysis of Design Expert 6.0 indicated that BRP, B, and SMJ very significantly influenced (P < 0.001) DMW and CY of C. militaris, respectively. The highest DMW (18.96 g/l) and CY (2.17 mg/g) were both obtained at a ratio of 53:6:42. The experiments' results indicated that the above mixture of these natural materials by D-optional mixture design can be used as a proper medium for the growth of mycelium and the production of cordycepin.