Biphasic Fermentation of Trapa bispinosa Shells by Ganoderma sinense and Characterization of Its Polysaccharides and Alcoholic Extract and Analysis of Their Bioactivity.

BACKGROUND: Trapa bispinosa shells (TBs) and its flesh (TBf) have been recognized for their medicinal properties, including antioxidant, antitumor, and immunomodulatory effects. Despite these benefits, TBs are often discarded as waste material, and their applications remain to be further explored. METHODS: In this study, we optimized the solid-state fermentation process of Ganoderma sinense (GS) with TBs using a response surface experiment methodology to obtain the fermented production with the highest water extract rate and DPPH free radical scavenging activity. We prepared and characterized pre-fermentation purified polysaccharides (P1) and post-fermentation purified polysaccharides (P2). Alcoholic extracts before (AE1) and after (AE2) fermentation were analyzed for active components such as polyphenols and flavonoids using UPLC-QTOF-MS/MS (ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry). Mouse macrophages (RAW 264.7) were employed to compare the immune-stimulating ability of polysaccharides and the antioxidant activity of AE1 and AE2. RESULTS: Optimal fermentation conditions comprised a duration of 2 days, a temperature of 14 °C, and a humidity of 77%. The peak water extract yield and DPPH free radical scavenging rate of the water extract from TBs fermented by GS were observed under these conditions. The enhanced activity may be attributed to changes in the polysaccharide structure and the components of the alcoholic extract. The P2 treatment group indicated more secretion of RAW 264.7 cells of NO, iNOS, IL-2, IL-10, and TNF-α than P1, which shows that the polysaccharides demonstrated increased immune-stimulating ability, with their effect linked to the NF-кB pathway. Moreover, the results of the AE2 treatment group indicated that secretion of RAW 264.7 cells of T-AOC and T-SOD increased and MDA decreased, which shows that the alcoholic extract demonstrated enhanced antioxidant activity, with its effect linked to the Nrf2/Keap1-ARE pathway. CONCLUSIONS: Biphasic fermentation of Trapa bispinosa shells by Ganoderma sinense could change the composition and structure of the polysaccharides and the composition of the alcoholic extract, which could increase the products' immunomodulatory and antioxidant activity.

Ganoderma lucidum-Derived Meroterpenoids Show Anti-Inflammatory Activity In Vitro.

Ganoderma lucidum, known as the "herb of spiritual potency", is used for the treatment and prevention of various diseases, but the responsible constituents for its therapeutic effects are largely unknown. For the purpose of obtaining insight into the chemical and biological profiling of meroterpenoids in G. lucidum, various chromatographic approaches were utilized for the title fungus. As a result, six undescribed meroterpenoids, chizhienes A-F (1-6), containing two pairs of enantiomers (4 and 5), were isolated. Their structures were identified using spectroscopic and computational methods. In addition, the anti-inflammatory activities of all the isolates were evaluated by Western blot analysis in LPS-induced macrophage cells (RAW264.7), showing that 1 and 3 could dose dependently inhibit iNOS but not COX-2 expression. Further, 1 and 3 were found to inhibit nitric oxide (NO) production using the Greiss reagent test. The current study will aid in enriching the structural and biological diversity of Ganoderma-derived meroterpenoids.

Total Synthesis of Ganoderma Meroterpenoids Cochlearol B and Its Congeners Driven by Structural Similarity and Biological Homology.

Secondary metabolites that have the same biological origin must share some relationship in their biosynthesis. Exploring this relationship has always been a significant task for synthetic biologists. However, from the perspective of synthetic chemists, it is equally important to propose, prove, or refute potential biosynthetic pathways in order to elucidate and understand the biosynthesis of homologous secondary metabolites. In this study, driven by the high structural similarity between the homologous Ganoderma meroterpenoids cochlearol B and ganocin B, two chemically synthetic strategies were designed and investigated sequentially for the synthesis of cochlearol B from ganocin B. These strategies include intramolecular metal-catalyzed hydrogen atom transfer (MHAT) and intramolecular photochemical [2+2] cycloaddition. The aim was to reveal their potential biosynthetic conversion relationship using chemical synthesis methods. As a result, a highly efficient total synthesis of cochlearol B, cochlearol T, cochlearol F, as well as the formal total synthesis of ganocins A-B, and ganocochlearins C-D, has been achieved. Additionally, a novel synthetic approach for the synthesis of 6,6-disubstituted 6H-dibenzo[b,d]pyran and its analogues has been developed through palladium(II)-catalyzed Wacker-type/cross-coupling cascade reactions.

Insights into Ganoderma fungi meroterpenoids opening a new era of racemic natural products in mushrooms.

Ganoderma meroterpenoids (GMs) containing 688 structures to date were discovered to have multiple remarkable biological activities. 65.6% of meroterpenoids featuring stereogenic centers from Ganoderma species are racemates. Further, GMs from different Ganoderma species seem to have their own characteristics. In this review, a comprehensive summarization of GMs since 2000 is presented, including GM structures, structure corrections, biological activities, physicochemical properties, total synthesis, and proposed biosynthetic pathways. Additionally, we especially discuss the racemic nature, species-related structural distribution, and structure-activity relationship of GMs, which will provide a likely in-house database and shed light on future studies on GMs.

Identification a novel Ganoderma FIP gene from Ganoderma capense and its functional expression in Pichia pastoris.

Ganoderma capense is a precious medicinal fungus in China. In this study, a novel fungal immunomodulatory protein gene, named as FIP-gca, was cloned from G. capense by homologous cloning. Sequencing analysis indicated that FIP-gca was composed of 336 bp, which encoded a polypeptide of 110 amino acids. Protein sequence blasting and phylogenetic analysis showed that FIP-gca shared homology with other Ganoderma FIPs. FIP-gca was effectively expressed in Pichia pastoris GS115 at an expression level of 166.8 mg/L and purified using HisTrap™ fast-flow prepack columns. The immunomodulation capacity of rFIP-gca was demonstrated by that rFIP-gca could obviously stimulate cell proliferation and increase IL-2 secretion of murine spleen lymphocytes. Besides, antitumor activity of rFIP-gca towards human stomach cancer AGS cell line was evaluated in vitro. Cell wound scratch assay proved that rFIP-gca could inhibit migration of AGS cells. And flow cytometry assay revealed that rFIP-gca could significantly induce apoptosis of AGS cells. rFIP-gca was able to induce 18.12% and 22.29% cell apoptosis at 0.3 µM and 0.6 µM, respectively. Conclusively, the novel FIP-gca gene from G. capense has been functionally expressed in Pichia and rFIP-gca exhibited ideal immunomodulation and anti-tumour activities, which implies its potential application and study in future.

Lanostane triterpenoids from the fruiting bodies of Ganoderma amboinense.

Lanostane-type triterpenoids are the main characteristic constituents in Ganoderma mushrooms. Phytochemical analysis on the ethanol extract of the fruiting bodies of Ganoderma amboinense led to isolation and identification of twelve previously undescribed lanostane triterpenoids (1-12). Their chemical structures were determined by HR-ESI-MS, IR, and NMR spectroscopic analysis, NMR calculation, as well as X-ray crystallography. All isolates were evaluated for the α-glucosidase inhibitory and anti-inflammatory activities. Compounds 1, 5, 6, and 11 showed significant α-glucosidase inhibitory activity with IC50 values ranging from 33.5 µM to 96.0 µM. Moreover, compound 12 showed anti-inflammatory activity with IC50 value of 21.7 ± 2.1 µM.

Characterization and Biological Studies of the Terpenoids from Ganoderma resinaceum and Serpula similis (Agaricomycetes).

Mycochemical properties and bioactivities of Ganoderma resinaceum and Serpula similis remain unexplored. The present study assessed antioxidant, cytotoxicity, and cell migration abilities of Ganoderma and Serpula extracts, followed by their phytochemical analyses. The MTT assay was conducted to determine the cytotoxicity along with the cell migration studies in human cancer cell lines. The antioxidant profiles were evaluated through DPPH and FRAP assays. Furthermore, LC-MS/MS analysis was performed to elucidate the phytochemicals responsible for anticancer and antioxidant activities. Significant concentration-dependent cytotoxicities of 12.7% and 13.7% were observed against HCT 116 cell lines at 1% and 5% concentrations of the G. resinaceum extract, respectively. Similarly, significant concentration-dependent cytotoxicities of 6.7% and 25.5% were observed at 1% and 5% concentrations of the S. similis extract, respectively. The extracts of G. resinaceum and S. similis both shows better anti-migration potential in lung cancer cells. Both extracts demonstrated good scavenging activity on DPPH and ferric ion free radicals. LC-MS analysis revealed 11 compounds from S. similis and 15 compounds from G. resinaceum fruiting bodies. Compounds such as terpenoids, alkaloids, cytotoxic peptides, and other metabolites were identified as major components in both extracts. These extracts exhibited cytotoxic activity against HCT 116 cancer cells, along with moderate antioxidant activity. This implies that the extracts might be used as bioactive natural sources in the pharmaceutical and food industries.

Antimalarial Lanostane Dimers from Artificially Cultivated Fruiting Bodies of Ganoderma weberianum.

Investigation of cultivated fruiting bodies of Ganoderma weberianum led to the isolation of 11 previously unreported lanostane dimers, ganoweberianones C (3a), D (4a), E (5a), F (6a), G (7a), and H (8a) and isoganoweberianones A (1b), B (2b), D (4b), G (7b), and H (8b). Six new ganodermanontriol derivatives as three pairs of diastereomers (11/12, 13/14, and 15/16) and five new ganoweberianic acids (17-21) were also isolated. A method for semisynthesis of lanostane dimers by condensation of natural lanostanes was established, which was utilized in the structure elucidation and NMR data assignments of the undescribed natural lanostane dimers. Ganoweberianone D (4a) and isoganoweberianone D (4b) showed significant antimalarial activity against Plasmodium falciparum K1 (multidrug-resistant strain) with IC50 values of 0.057 and 0.035 µM, respectively, whereas their cytotoxicity to Vero cells was weaker (IC50 8.1 and 19 µM, respectively).

Biological Activity of Ganoderma Species (Agaricomycetes) from Sonoran Desert, Mexico.

Ganoderma species have been used in folk medicine against different illnesses and are characterized by producing a diversity of bioactive metabolites (triterpenoids, polysaccharides, flavonoids, and phenols) with numerous medicinal effects (anti-proliferative, antioxidant, anti-inflammatory, and antibacterial). This work aims to evaluate ethanolic extracts of fruiting bodies of Ganoderma oerstedii, G. weberianum, and G. subincrustatum strains from the Sonoran Desert in the anti-proliferative activity by the MTT assay on cancer cell lines; anti-inflammatory effect by quantifying nitric oxide (NO) production; antioxidant activity by DPPH, ABTS, and FRAP assays; total phenolic and flavonoid content by Folin-Ciocalteu and AlCl3 method, respectively; antibacterial activity by the broth microdilution method against Escherichia coli and Staphylococcus aureus. Extracts showed anti-proliferative activity with IC50 < 100 µg/mL on the cancer cell lines MDA-MB-231, A549, and HeLa, except G. subincrustatum extract with an IC50 > 100 µg/mL; anti-proliferative activity was not selective, being affected non-cancerous cell line ARPE-19. Extracts showed significant inhibition of NO release in cells stimulated by LPS, up to 60% with G. subincrustatum and G. oerstedii, and 47% with G. weberianum. All tested assays showed moderate antioxidant potential; the most active was G. lucium (control strain) with IC50 of 69 and 30 µg/mL by DPPH and ABTS respectively; and 271 µg Trolox equivalents/g by FRAP. Total phenols and flavonoids ranged from 38 to 56 mg GAE/g and 0.53 to 0.93 mg QE/g, respectively. A significant correlation was found between the antioxidant activities revealed by DPPH, ABTS, and FRAP with total phenol and flavonoid contents. Antibacterial activity was weak against S. aureus (MIC50 > 10 mg/mL). These results demonstrate that tested Ganoderma mushrooms have medicinal potential such as anti-inflammatory and anti-proliferative.

A Comprehensive Review on the Chemical Composition, Pharmacology and Clinical Applications of Ganoderma.

Ganoderma is the dried fruiting bodiy of Ganoderma lucidum (Leyss.ex Fr.) Karst. or Ganoderma sinense Zhao, Xu et Zhang, belonging to the family Polyporaceae, which grows mainly in tropical, subtropical, and temperate regions. As a traditional Chinese medicine, Ganoderma has been used in China for more than 2000 years because of its medicinal properties, such as relieving cough and asthma, providing nourishment, and strengthening. Currently, more than 470 natural compounds have been obtained from the fungus, mainly including terpenoids, steroids, alkaloids, phenols, and other types of compounds. Modern pharmacological studies have shown that Ganoderma has antitumor, anti-inflammatory, hypoglycemic, hypolipidemic, and immunomodulatory effects. It is mainly used in clinical practice for the treatment of Diabetic Nephropathy and malignant tumors, with few side effects and high safety. This paper reviews the progress of research on its chemical composition, pharmacological effects, and clinical applications, with the goal of providing a basis for the better development and utilization of Ganoderma.

Antiparasitic Activity of Compounds Isolated from Ganoderma tuberculosum (Agaricomycetes) from Mexico.

The genus Ganoderma has a long history of use in traditional Asiatic medicine due to its different nutritional and medicinal properties. In Mexico, the species G. tuberculosum is used in indigenous communities, for example, the Wixaritari and mestizos of Villa Guerrero Jalisco for the treatment of diseases that may be related to parasitic infections; however, few chemical studies corroborate its traditional medicinal potential. Thereby, the objective of this study was to isolate and identify anti-parasitic activity compounds from a strain of G. tuberculosum native to Mexico. From the fruiting bodies of G. tuberculosum (GVL-21) a hexane extract was obtained which was subjected to guided fractioning to isolate pure compounds. The in vitro anti-parasitic activity of the pure compound (IC50) was assayed against Leishmania amazonensis, Trypanosoma cruzi, Acanthamoeba castellanii Neff, and Naegleria fowleri. Furthermore, the cytotoxicity (CC50) of the isolated compounds was determined against murine macrophages. The guided fractioning produced 5 compounds: ergosterol (1), ergosta-4,6,8(14),22-tetraen-3-one (2), ergosta-7,22-dien-3ß-ol (3), 3,5-dihydroxy-ergosta-7,22-dien-6-one (4), and ganoderic acid DM (5). Compounds 2 and 5 showed the best anti-parasitic activity in an IC50 range of 54.34 ± 8.02 to 12.38 ± 2.72 µM against all the parasites assayed and low cytotoxicity against murine macrophages. The present study showed for the first time the in vitro anti-parasitic activity of compounds 1-5 against L. amazonensis, T. cruzi, A. castellanii Neff, and N. fowleri, corroborating the medicinal potential of Ganoderma and its traditional applications.

Studies of Antioxidant and Cytotoxic Activity in Ready-to-Drink Wild Ganoderma Teas: An In Vitro Approach.

Ganoderma is a medicinally important mushroom and has been used since ancient times. However, mostly G. lucidum has been used for therapeutic purposes, in form of tea, dietary and drug supplements but other species of Ganoderma are still remaining underexploited. This study is the first approach to valorize Ganoderma teas prepared from different wild species of Ganoderma other than G. lucidum with respect to both phytochemically and therapeutically through investigation of their phytochemical, carbohydrate contents and exploring their antioxidant activity. Phytochemical contents such as phenol and flavonoids were quantified using spectrophotometry methods. The carbohydrate content of the teas was estimated by phenol sulphuric acid method. The biochemical analysis revealed the teas contained a notable amount of phenolic compounds ranging from 19.15 to 40.2 µg GAE/mg of extract and also showed significant content of flavonoids. Further, antioxidant potential in terms of DPPH and ABTS radical scavenging ability and total antioxidant capacity was also evaluated. According to the results, G. resinaceum tea showed better potential in scavenging DPPH (EC50 36 ug/mL) and ABTS radicals (EC50 3 9 ug/mL) whereas the least effect was shown for the tea of G. ahmedi. Therefore, tea showing the best results, i.e. G. resinaceum tea, was also analyzed for cytotoxicity on breast cancer cells. It was found that the tea made from G. resinaceum inhibited cellular growth and proliferation in a dose-dependent manner with maximum growth inhibition (61%) observed at the highest concentration of 2.3 mg/mL. The presence of a greater quantity of carbohydrates in G. resinaceum tea also justified the remarkable anticancer potential of the tea. Overall, our findings indicated that a few wild species of Ganoderma other than G. lucidum have great potential to be valued as a healthy beverage with immense therapeutic benefits.

Lanostane triterpenoids from mycelia-associated Ganoderma sinense and their anti-inflammatory activity.

Seven previously undescribed lanostane triterpenoids, ganoderic acid M1 (1), M2 (2), M3 (3), M4 (4), M5 (5), M6 (6), and M7 (7), together with eight known compounds, were isolated from mycelia of the basidiomycete Ganoderma sinense (Ganodermataceae). The structures of all compounds were elucidated by spectroscopic analysis. The possible biosynthetic pathway of these fifteen triterpenoids was proposed. Some of the compounds were evaluated for their anti-inflammatory activity by measuring the production of nitric oxide (NO), TNF-α, and IL-6 in RAW264.7 macrophage cells induced by lipopolysaccharide. Lanosta-7,9(11),24-trien-3ß,15α,22ß-triacetoxy-26-oic acid (14) exhibited the strongest inhibition of NO production with an IC50 of 0.6 ± 0.1 µM and completely inhibited the secretion of TNF-α and IL-6 at 10 µM. The structure-activity relationship of the anti-inflammatory activity is discussed.

Lanostane triterpenoids with anti-proliferative and PTP1B/α-glucosidase inhibitory activities from the fruiting bodies of Ganoderma calidophilum.

Twelve previously undescribed and four known lanostane triterpenoids were isolated from the fruiting bodies of Ganoderma calidophilum. The structures of undescribed compounds, ganodecalones H-S (1-12), were elucidated by extensive spectroscopic analysis as well as ECD and NMR calculations. Compound 4 showed significant inhibitory activity against human leukaemia cell line K562, gastric cancer cell line SGC-7901, and cervical cancer cell line HeLa with IC50 values of 13.10 ± 0.19, 17.26 ± 4.75, and 4.36 ± 0.58 µM, respectively. Compound 16 exhibited inhibitory potency against protein tyrosine phosphatase 1B (PTP1B) and α-glucosidase with IC50 values of 30.2 ± 0.13 µM and 120.6 ± 0.14 µM, respectively. The binding sites and interactions of 16 with PTP1B and α-glucosidase were revealed using molecular docking simulations.

Sterols Content of Fruiting Bodies of Medicinal Artist's Bracket Mushroom Ganoderma applanatum (Agaricomycetes) Collected in Armenia.

The qualitative analysis of hexane extracts obtained from different trama layers (WT, T1-T4) of dried fruiting bodies of medicinal bracket fungus Ganoderma applanatum collected in the Tavoush region of North-East Armenia was performed by GC-MS analysis. Three sterols [(7.22-ergostadienon, ergosterol and ergosta-14.22-diene-3-ol (3ß, 5α, 22E)] have been identified. The results have shown that the content and ratio of sterols differ in analyzed trama samples. The highest amount of sterols was detected in middle parts of T2 and T3 layers, while content of sterols gradually decreased to the upper cortical (T4) and lower hymenial (T1) layers. The chromatographic profiles of identified compounds indicate that different sterols dominated in each layer: 7.22-ergostadienon in T4, ergosterol in T3, T2, and T1. The average weight loss of analyzed trama samples during six days of drying was about 40 wt.% (37.0-43.49 wt.%) of the total weight of basidiome, which decreased up to 5 wt.% in the next two days. The complete extraction of sterols lasted six days. Its further prolongation leads to stationary phase without an increase in the amount of extracted sterols.

Determination and Chemotaxonomic Analysis of Lanostane Triterpenoids in the Mycelia of Ganoderma spp. Using Ultra-performance Liquid Chromatography-Tandem Mass Spectrometry (I).

A comprehensive and sensitive method combining ultra-performance liquid chromatography with tandem mass spectrometry was developed for the quantification of characteristic triterpenoids in Ganoderma mycelia. Eight ganoderic acids previously isolated from the mycelia of Ganoderma lingzhi were separated with a binary mobile phase on a reversed-phase C18 column. A triple quadrupole mass spectrometer equipped with an electrospray ionization source was used as the detector in the negative ion mode. Identification and quantitation of target ganoderic acids were accomplished using the dynamic multiple reaction monitoring mode. The developed method was validated in terms of linearity, precision, accuracy, stability, and recovery. The method was first applied to quantify the contents of eight ganoderic acids in the mycelia of G. lingzhi at different times to determine the optimum fermentation conditions. Subsequently, the distribution of triterpenoids and the contents of eight ganoderic acids in sixteen different Ganoderma species were investigated. The results indicated that UV chromatography combined with dynamic multiple reaction monitoring quantification was an effective chemotaxonomy method for Ganoderma species identification. This study also provided a helpful analytical methodology for both scientific and industrial applications in the quality control of Ganoderma triterpenoids.

Isolation and characterization of dihydropyran-ring containing meroterpenoids from Ganoderma lucidum and their inhibitory activity against renal fibrosis-related protein expression.

The Ganoderma lucidum mushroom, which has been used as a traditional medicine in China for more than 2000 years, is a source of many interesting natural product. In this study, the five undescribed minor meroterpenoids baoslingzhines F-J (1-5), containing a dihydropyran moiety, were isolated as racemic mixtures from the fruiting bodies of G. lucidum. These substances were structurally and stereochemically characterized by using spectroscopic and computational methods. Chiral HPLC was employed to separate the (+)- and (-)-antipodes. A survey of the activities against kidney fibrosis showed that both enantiomers of baoslingzhines F-J inhibit expression of renal fibrosis-related proteins, including fibronectin, collagen I and ɑ-SMA in TGF-ß1-induced rat kidney proximal tubular cells.

Lanostane triterpenoids with anti-proliferative and anti-inflammatory activities from medicinal mushroom Ganoderma lingzhi.

Eight previously undescribed lanostane triterpenoids and nine known ones were identified from the fruiting bodies of Ganoderma lingzhi S.H. Wu, Y. Cao & Y.C. Dai. Their structures were determined based on spectroscopic data and quantum chemical calculations. Structurally, ganoderane GL-1, featuring a hydrogenated tetramethyls-phenanthraquinone, represents the first example in lanostane nor-triterpenoid group. Biologically, ganoderanes GL-2 and GL-3, distinguished by the presence of a rare "1,11-epoxy" moiety, exhibited significant inhibition against nitric oxide production induced by lipopolysaccharide in RAW264.7 macrophage cells, while ganoderanes GL-4 and GL-8 exhibited bifunctional activities of anti-proliferation and anti-inflammation.

A review of Ganoderma lucidum polysaccharides: Health benefit, structure-activity relationship, modification, and nanoparticle encapsulation.

Ganoderma lucidum polysaccharides possess unique functional properties. Various processing technologies have been used to produce and modify G. lucidum polysaccharides to improve their yield and utilization. In this review, the structure and health benefits were summarized, and the factors that may affect the quality of G. lucidum polysaccharides were discussed, including the use of chemical modifications such as sulfation, carboxymethylation, and selenization. Those modifications improved the physicochemical characteristics and utilization of G. lucidum polysaccharides, and made them more stable that could be used as functional biomaterials to encapsulate active substances. Ultimate, G. lucidum polysaccharide-based nanoparticles were designed to deliver various functional ingredients to achieve better health-promoting effects. Overall, this review presents an in-depth summary of current modification strategies and offers new insights into the effective processing techniques to develop G. lucidum polysaccharide-rich functional foods or nutraceuticals.

Significance of culture period on the physiochemistry and anti-cancer potentials of polysaccharides from mycelia of Ganoderma lucidum.

Ganoderma lucidum polysaccharides (GPS) have many functions. Polysaccharides are abundant in G. lucidum mycelia, but it is unclear whether the production and chemical characteristics of polysaccharides are related to the liquid cultural periods of mycelia. This study harvests G. lucidum mycelia at different cultural stages and isolates GPS and sulfated polysaccharides (GSPS) separately to determine an optimum cultural duration. After 42 and 49 days of mycelia are found to be the best times to harvest GPS and GSPS. Characteristic studies show that glucose and galactose are the main sugars in GPS and GSPS. The molecular weights of various GPS and GSPS are mainly distributed at >1000 kDa and from 101 to 1000 kDa. The sulfate content of GSPS at Day 49 is greater than that at Day 7. GPS and GSPS at 49 days exhibits a good anticancer effect but does not affect normal fibroblasts. GPS and GSPS that is isolated on day 49 inhibits lung cancer by suppressing epidermal growth factor receptor (EGFR) and transforming growth factor beta receptor (TGFßR)-mediated signaling networks. These results show that the mycelia of G. lucidum that are cultured for 49 days exhibit the best biological characteristics.