Therapeutic properties in Tunisian hot springs: first evidence of phenolic compounds in the cyanobacterium Leptolyngbya sp. biomass, capsular polysaccharides and releasing polysaccharides

Abstract

BackgroundIn Tunisia, the use of hot spring waters for both health and recreation is a tradition dating back to Roman times. In fact, thermal baths, usually called “Hammam” are recommended as a therapeutic and prophylactic measure against many types of illness and toxicity. While the chemical concentration of thermal water is admittedly associated with its therapeutic effects, the inclusion in spa waters of efficient bioproduct additives produced by photosynthetic microorganisms and that act against oxidative stress may comprise a significant supplementary value for thermal centers. The aim of this study was to investigate the antioxidant potential of the Tunisian thermophilic cyanobacterium Leptolyngbya sp. and to determine its phytochemical constituents and phenolic profile.MethodsBME (Biomass Methanolic Extract), CME (Capsular polysaccharides Methanolic Extract) and RME (Releasing polysaccharides Methanolic Extract) of Leptolyngbya sp. were examined for their antioxidant activities by means of DPPH, hydroxyl radical scavenging and ferrous ion chelating assays. Their total phenols, flavonoids, carotenoids, Mycosporine-like amino acids (MAAs) and vitamin C contents, as well as their phenolic profiles were also determined.ResultsBME has the highest content of phenols (139 ± 1.2 mg/g), flavonoids (34.9 ± 0.32 mg CEQ/g), carotenoids (2.03 ± 0.56 mg/g) and vitamin C (15.7 ± 1.55 mg/g), while the highest MAAs content (0.42 ± 0.03 mg/g) was observed in CME. BME presented both the highest DPPH and hydroxyl radical scavenging ability with an IC50 of 0.07 and 0.38 mg/ml, respectively. The highest ferrous chelating capacity was detected in CME with an IC50 = 0.59 mg/ml. Phenolic profiles revealed the presence of 25 phenolic compounds with the existence of hydroxytyrosol, oleuropein, resveratrol and pinoresinol.ConclusionThe study demonstrated that the cyanobacterium Leptolyngbya sp. possesses abundant natural antioxidant products which may have prophylactic and therapeutic effects on many types of illness and toxicity. The present findings not only explain and reinforce the rationale behind traditional therapeutic practices in Tunisia in the exploitation of the country’s hot springs, but support the addition of Leptolyngbya to thermal waters as a means to enhance the value and reputation of the curative nature of Tunisian thermal waters.

Ganoderma lucidum Polysaccharides Prevent Palmitic Acid-Evoked Apoptosis and Autophagy in Intestinal Porcine Epithelial Cell Line via Restoration of Mitochondrial Function and Regulation of MAPK and AMPK/Akt/mTOR Signaling Pathway

“…Phytochemicals have been used in pharmaceutical and dietary therapy including polysaccharides, alkaloids, steroids, carotenoids, phenolic glycosides, flavonoids, and other nitrogen-containing compounds [15]. The search for phytochemicals without toxic side effects that can protect IECs from damage is a crucial way toward that development of effective treatment strategies for intestinal diseases before overt clinical symptoms develop.…”

The Role of Thermal Water in Chronic Skin Diseases Management: A Review of the Literature

“…Since 1998 there has been a growing interest in the characterization of the microbial community of thermal waters [ 66 , 67 ]. On one side, the microbial evaluation of water for human use is subjected to sanitary control, in order to search for coliform bacteria, Salmonella spp., and fecal Streptococci [ 68 , 69 ] and on the other side, the analysis of the microbial composition of the thermal waters revealed the presence of dynamic microbial communities that function in different microenvironmental conditions [ 70 , 71 , 72 , 73 ], made up of peculiar and unusual microbial species with potential therapeutic effect [ 74 , 75 , 76 ]. Several environmental factors shape microbial communities that inhabit thermal water like temperature, water chemical composition, and pH as well as the distance from the sources [ 71 ].…”

“…Further studies focused their attention also on the metabolic potential of microbiota associated with thermal spring water to identify a promising source of enzymes with biotechnological potential [ 85 , 86 ]. While the chemical concentrations in thermal waters are admittedly associated with their therapeutic effects [ 87 ], the inclusion of efficient bioproduct additives produced by photosynthetic organisms and which act against oxidative stress may comprise a significant supplementary value for the increasingly competitive sector of balneotherapy [ 76 ], such as a Cyanobacterium Leptolyngbya sp. that possesses abundant natural antioxidant products which may have prophylactic and therapeutic effects on many types of illness and toxicity [ 76 ].…”

“…While the chemical concentrations in thermal waters are admittedly associated with their therapeutic effects [ 87 ], the inclusion of efficient bioproduct additives produced by photosynthetic organisms and which act against oxidative stress may comprise a significant supplementary value for the increasingly competitive sector of balneotherapy [ 76 ], such as a Cyanobacterium Leptolyngbya sp. that possesses abundant natural antioxidant products which may have prophylactic and therapeutic effects on many types of illness and toxicity [ 76 ]. In addition, an original microorganism, Aquaphilus dolomiae , never described in another medium, has very recently been identified in the Avene thermal spring water.…”

The Chemistry, Biochemistry and Pharmacology of Marine Natural Products from Leptolyngbya, a Chemically Endowed Genus of Cyanobacteria

“…The extract from a thermophilic cyanobacterium Leptolyngbya sp. collected from northern Tunisia was screened by HPLC and showed the presence of 25 phenolic compounds—gallic acid ( 60 ), hydroxytyrosol ( 61 ), protocatechuic acid ( 62 ), vanillic acid ( 63 ), isovanillic acid ( 64 ), 3-hydroxybenzoic acid (3-HBA) ( 65 ), 4-hydroxybenzoic acid (4-HBA) ( 66 ), resorcinol ( 67 ), naphtoresorcinol ( 68 ), syringic acid ( 69 ), catechol ( 70 ), and oleuropein ( 71 ) ( Figure 19 ); chlorogenic acid ( 72 ), dihyrdro- p -coumaric acid ( 73 ), dihyrdro- m -coumaric acid ( 74 ), ferulic acid ( 75 ), and rosamerinic acids ( 76 ) ( Figure 20 ); catechin ( 77 ), luteolin-7-glucoside ( 78 ), apigenin-7-glucoside ( 79 ), flavone ( 80 ), naringenin ( 81 ), luteolin ( 82 ), and apigenin ( 83 ) ( Figure 21 ); resveratrol ( 84 ) and pinoresinol ( 85 ) ( Figure 22 )—demonstrating that Leptolyngbya may constitute a rich source of antioxidant natural products [ 83 , 84 ]. These compounds also have inherent UV-absorbing properties, albeit at more restricted wavelengths than scytonemin ( 58 ).…”