Bath Sponges Research Articles

3D Spongin Scaffolds as Templates for Electro-Assisted Deposition of Selected Iron Oxides.

The skeletons of marine sponges are ancient biocomposite structures in which mineral phases are formed on 3D organic matrices. In addition to calcium- and silicate-containing biominerals, iron ions play an active role in skeleton formation in some species of bath sponges in the marine environment, which is a result of the biocorrosion of the metal structures on which these sponges settle. The interaction between iron ions and biopolymer spongin has motivated the development of selected extreme biomimetics approaches with the aim of creating new functional composites to use in environmental remediation and as adsorbents for heavy metals. In this study, for the first time, microporous 3D spongin scaffolds isolated from the cultivated marine bath sponge Hippospongia communis were used for electro-assisted deposition of iron oxides such as goethite [α-FeO(OH)] and lepidocrocite [γ-FeO(OH)]. The obtained iron oxide phases were characterized with the use of scanning electron microscopy, FTIR, and X-ray diffraction. In addition, mechanisms of electro-assisted deposition of iron oxides on the surface of spongin, as a sustainable biomaterial, are proposed and discussed.

Marine sponges as promising candidates for integrated aquaculture combining biomass increase and bioremediation: an updated review

Sponge farming has been experimentally performed for more than 100 years, with early attempts mainly devoted for the supply of bath sponges and for ornamental purposes. During the last decades, sponge farming has been proposed to produce biomass specifically for those species from which many structurally diverse bioactive compounds were isolated, frequently present in a low concentration that limits their commercial production. This point is very important because it offers an environmental-friendly approach for the use of sponges as a source of natural compounds for pharmacological, cosmeceutical, and nutraceutical industries. In addition, sponges can have an ecological role as filter-feeding animals with a great significance in marine benthic communities. Thanks to their aquiferous system, they can filter large amounts of sea water, retaining up to 80% of suspended particles, resulting in a good system to bioremediate the marine environment from different contaminants. Remarkably, few attempts at integrating aquaculture systems were performed by combining the increase in sponge biomass and their use for bioremediation, showing impressive results and opening new possibilities in the aquaculture sector. This review concerns both in situ and lab-based aquaculture methods for the production of sponge biomass and for the sponge-related bioremediation of the marine environment focusing on microorganisms and contaminants (heavy metals, pesticides, microplastics, and others). Moreover, a first overview about integrated aquaculture combining biomass increase and bioremediation, as a challenging perspective for marine biotechnologies, is included.

Do Sustainably Reared Marine Sponges Represent A Potential New Product in Aquariology? A Citizen Science-Based Approach

Marine sponges have historically been targeted for different purposes, mainly as bath sponges or more recently as a source of bioactive metabolites. However, their use as ornamental species for aquariology is less thoroughly studied. In light of the rise in the importance of sustainable production systems and to valorize the biomass obtained from them, this work assessed the market potential of sustainably reared marine sponges in Italian aquariology. Information was obtained by means of an anonymous questionnaire distributed using social media and printed QR codes targeting Italian aquariophily groups. A total of 101 people from almost all Italian regions participated in the study. Among the people with marine aquariums, almost two-thirds had marine sponges (obtained mainly from fishing discards and trusted shops), and those without them stated that there was no availability in the specialized shops. However, when people were asked about a hypothetical change in purchase intention or frequency of these invertebrates, 68.3% of the respondents showed a positive attitude toward the idea of acquisition. This study constitutes the first preliminary assessment of the valorization potential for sustainably cultivated sponges as ornamental species, which shows a promising prospective in the Italian aquariology sector.

Sponges as Emerging By-Product of Integrated Multitrophic Aquaculture (IMTA)

The use of marine sponges dates back thousands of years, and interest in these animals is increasing as new applications are discovered. Their potential is extensive, both in their ancient and still popular use as bath sponges for cosmetics and regarding the more recent discovery of bioactive secondary metabolites mainly of interest for the pharmaceutical industry and the less developed aquariology. Despite their proven biofiltration and ecosystem restoration ability and the biomass supply problem for the interested industries, few integrated multi-trophic aquaculture (IMTA) systems incorporate these invertebrates in their facilities. Therefore, in this brief review, the benefits that marine sponges could bring to rapidly growing IMTA systems are summarized, highlighting their suitability for a circular blue economy.

Why Are Scientists Interested in Marine Sponges and Their Bacteria?

When you think of sponges, what comes to your mind? Some people might think of bath, kitchen, or makeup sponges. In reality, those objects are all based on ancient living creatures found in aquatic environments, called marine sponges. These animals have bodies full of holes and live attached to a surface. Sadly, marine sponges are at risk of disappearing forever, because of the pollution of the oceans. Scientists discovered that various bacteria live inside sponges. These bacteria produce substances that can help sponges to get stronger and to thrive even in very polluted places. But what is even more interesting is that these substances can be used to improve human health and the health of the environment. Yet, we know little about the potential of this tiny and magnificent world. So, the research must continue!

Population dynamics and life history traits of the non-indigenous Paranthura japonica Richardson (1909) in a recently invaded Mediterranean site

Most of marine non-indigenous species still suffers of large gaps in knowledge even regarding the most basic life history traits. The present study aims to understand the biology and ecology of the pacific isopod Paranthura japonica in a newly invaded site in the Central Mediterranean Sea, specifically focusing on its population dynamics in response to seasonal variation of environmental parameters. To collect standardised samples of this minute benthic species with cryptic behaviour, we use nylon bath sponges as Artificial Substrate Units, and an image analysis software for digital measurements of total body length. We conclude that P. japonica, native to the cold Okhotsk sea, has well adapted to the warmer Mediterranean conditions. Its population has been found well-established and persistent throughout the year, while its numeric positive response to increasing temperature was one of our most surprising findings. In fact, reproductive events occur throughout the year, but peak during summer months. Finally, we show that nylon bath sponges represent an efficient artificial substrate for obtaining quantitative samples of peracarid crustaceans.

High affinity of 3D spongin scaffold towards Hg(II) in real waters

This study focuses on the ability of commercial natural bath sponges, which are made from the skeletons of marine sponges, to sorb Hg from natural waters. The main component of these bath sponges is spongin, which is a protein-based material, closely related to collagen, offering a plenitude of reactive sites from the great variety of amino acids in the protein chains, where the Hg ions can sorb. For a dose of 40 mg L−1 and initial concentration of 50 μg L−1 of Hg(II), marine spongin (MS) removed ~90% of Hg from 3 water matrixes (ultrapure, bottled, and seawater), corresponding to a residual concentration of ~5 μg L−1, which tends to the recommend value for drinking water of 1 μg L−1. This value was maintained even by increasing the MS dosage, suggesting the existence of a gradient concentration threshold below which the Hg sorption mechanism halts. Kinetic modelling showed that the Pseudo Second-Order equation was the best fit for all the water matrixes, which indicates that the sorption mechanism relies most probably on chemical interactions between the functional groups of spongin and the Hg ions. This material can also be regenerated in HNO3 and reused for Hg sorption, with marginal losses in efficiency, at least for 3 consecutive cycles.

Past and present of a Mediterranean small-scale fishery: the Greek sponge fishery—its resilience and sustainability

Global change impacts Mediterranean fisheries and the dependent human populations. Overfishing and epizootic diseases related to extreme climatic events are currently accepted as the main threats to the production of commercial bath sponges. Believing that other factors could have impacted this insular fishery, we assembled a 150-year-long series of sponge fishing data for Greece that was analyzed in relation with variations of the pressure and of the socio-economic contexts. Sponge fishing experienced huge variations, with notably two distant short periods when the production collapsed (late nineteenth century and between 1985 and 1991). Before the 1970s, these variations are mainly attributed to socio-economic and political changes. The monitoring of the catches per unit effort indicates a clear overfishing impact only after 1977. However, after the last collapse of the overall production which followed the severe disease outbreak of the late 1980s, the catch per unit effort showed a positive trend, which tends to indicate that the stocks available bear the present fishing pressure. Fishermen have adapted towards sustainable practices, by reducing their crew and also diversifying their targets, which nevertheless calls to a more accurate monitoring of such a small-scale fishery.

A first preliminary study of the shallow water sponge fauna from Cyprus Island (Eastern Mediterranean).

Currently, more than 8,500 valid sponge species are reported in the World Porifera Database (http://www.marinespecies.org/porifera/) (van Soest et al. 2018). The Mediterranean Sea sponge fauna, counting almost 700 species, is one of the best documented in the world (Pronzato 2003; Pansini et al. 2011; van Soest et al. 2018) but the eastern part of the basin is by far less studied, in comparison with other Mediterranean areas (Pansini et al. 2000; Voultsiadou Vafidis 2004; Topaloğlu Evcen 2014). A small number of species, mainly belonging to the cosmopolitan genus Spongia (Dictyoceratida), are commonly used as bath sponges. Aim of this work is to provide further information on Cyprus Island sponges in general and on species that had commercial importance in the past.

Kalymnos, the island which made history in sponge fishery. Data on physical parameters, elemental composition and DNA barcode preliminary results of the most common bath sponge species in Aegean Sea

Kalymnos island is the last bulwark of the sponge fishery. The economy of the island was based almost exclusively on the harvesting and treatment of commercial species of sponges. Nowadays, 30 years after the desertification of all the sponge fishing grounds, the populations recover even in shallow waters (5–15 m) where the species Spongia (Spongia) officinalis Linnaeus, 1759 and Hippospongia communis (Lamarck, 1814) are mainly found. Signs of the disease were detected only in 0.6% of the harvested sponges. In this paper the traditional method for whitening bath sponges is described. In order to identify three sponge species Spongia (Spongia) officinalis, Spongia (Spongia) zimocca Schmidt, 1862 and Hippospongia communis, classical and molecular methods were used. Concerning the classical methods, scanning electron microscopy (SEM) was used and the diameter of the sponges’ secondary fibers was measured. The softness, the elasticity and the resistance in tension are important parameters in order to define the commercial value of the sponges. Physical parameters, as tensile strength, module of elasticity, and the chemical composition can be strongly correlated with the commercial value of these sponges. We measured the tensile strength, the module of elasticity, and the elemental composition of the three sponge species before and after the chemical treatment used for the “whitening procedure”. We give a short description of reliable morphological characters used for the taxonomy of the species involved in our experiments. In addition we include preliminary results from the application of a molecular method based on mitochondrial DNA analysis to distinguish between S. (S.) officinalis and H. communis.

First Report of Gray Mold Disease of Sponge Gourd (Luffa cylindrica) Caused by Botrytis cinerea in Korea

cal vegetable belongs to the family Cucurbitaceae. Luffa gourds are grown primarily for their fibrous tissue skeleton, which is commonly used as scrubbers, cleaning pads or bath sponges, but green immature fruits were cooked as vegetable and eaten as squash or substituted for cucumber in salads (Oboh and Aluyor, 2009). Botrytis cinerea (teleomorph Botryo­ tinia fuckeliana) is an air borne, ubiquitous filamentous fungal pathogen and may cause gray mold on a variety of dicotyledonous plants, including many vegetables, fruits, ornamental flowers, and greenhouse plants (Elad, 1997; Jarvis, 1977). The pathogen is a necrotroph, inducing host cell death resulting in serious damage to plant tissues culminating in rot of the plant (Govrin and Levine, 2000; Staats et al., 2005). Botrytis infections are favored by a cool weather, rainy spring season and summer temperatures of approximately 15C (60F). Gray mold can be particularly damaging when rainy and/or damp weather occurs over several days. Since 2014, gray mold of sponge gourd caused by B. cinerea has been found at different locations in Korea. The aim of the present study was to identify the causal agent associated with gray mold observed on sponge gourd in Korea, based on culture characteristics, molecular phylogenetics, and pathogenicity.

Recovery of the commercial sponges in the central and southeastern Aegean Sea (NE Mediterranean) after an outbreak of sponge disease

The distribution and biometry of commercial sponges (Porifera) in coastal areas of the central and southeastern Aegean Sea was investigated to estimate the recovery progress of the populations eight years after the first appearance of sponge disease. Signs of the disease were detected only in 1.6% of the harvested sponges. Multivariate analysis on the percentage abundance of sponges showed two distinct groups among the sixteen fishing grounds studied: the eight deep (50-110 m) and the eight shallow ones (<40 m). The group from the deep depths consisted of Spongia officinalis adriatica, S. agaricina and S. zimocca. The infralittoral zone was characterized by the presence of Hippospongia communis, S. officinalis adriatica and S. officinalis mollissima. These bath sponges showed an enhanced abundance in the eastern Cretan Sea (S. Aegean Sea). In addition, their dimensions, particularly height, increased with increasing depth. It is indicated that the hydrographic conditions prevailing in the eastern Cretan Sea affected the repopulating processes of sponge banks. In each species, the biometric characteristics of the experimental specimens were similar to those of the sponges found in the market and harvested at respective depths prior to the appearance of sponge disease.

Aegean Bath Sponges: Historical Data and Current Status

This study attempts to evaluate the status of the populations of bath sponges (species of the genera Spongia and Hippospongia) in the Aegean, combining historical sources dated before a series of disease outbreaks that occurred from 1986 on, unpublished data obtained during the recovery phase after the first incident, as well as a current survey of the main spongiferous beds in the area. The latter was implemented through an extensive sampling trip assisted by professional sponge fishermen, including 55 stations distributed in 17 Aegean islands. Our analysis of population and morphometric data exhibits regeneration potential for bath sponge stocks, yet highlights the contrast between their present status and that of historical times. Uniformity is not evident, as several populations retain high abundances, while simultaneously areas purportedly rich in bath sponges appear deprived. Small-scale environmental regimes in the Aegean are proposed as the shaping factors of this situation; however, the importance of additional elaborate studies and the implementation of an effective regulation scheme regarding their fisheries are stressed.

Farming Sponges to Supply Bioactive Metabolites and Bath Sponges: A Review

Sponges have been experimentally farmed for over 100 years, with early attempts done in the sea to supply "bath sponges". During the last 20 years, sponges have also been experimentally cultured both in the sea and in tanks on land for their biologically active metabolites, some of which have pharmaceutical potential. Sea-based farming studies have focused on developing good farming structures and identifying the optimal environmental conditions that promote production of bath sponges or bioactive metabolites. The ideal farming structure will vary between species and regions, but will generally involve threading sponges on rope or placing them inside mesh. For land-based sponge culture, most research has focused on determining the feeding requirements that promote growth. Many sea- and land-based studies have shown that sponges grow quickly, often doubling in size every few months. Other favorable results and interesting developments include partially harvesting farmed sponges to increase biomass yields, seeding sexually reproduced larvae on farming structures, using sponge farms as large biofilters to control microbial populations, and manipulating culture conditions to promote metabolite biosynthesis. Even though some results are promising, land-based culture needs further research and is not likely to be commercially feasible in the near future. Sea-based culture still holds great promise, with several small-scale farming operations producing bath sponges or metabolites. The greatest potential for commercial bath sponge culture is probably for underdeveloped coastal communities, where it can provide an alternative and environmentally friendly source of income.

Sponges of economical interest in the Eastern Mediterranean: an assessment of diversity and population density

The aim of this paper was to investigate diversity and population density of sponges with manifest or potential economical interest for the first time in the Eastern Mediterranean. For this purpose, the area of Dodecanese, an Aegean area traditionally harvested for sponges was surveyed for bath sponges and species known as sources of bioactive compounds. Twenty stations of diverse orientation, substrate inclination and type of substratum, located on seven islands, were surveyed and totally 36 demosponge species were found. The data, collected with a non‐destructive method, were subjected to multivariate analysis which showed that sponge diversity was higher in areas with vertical cliffs. A considerable spatial variation was revealed by the formation of two groups of stations, according to sponge species presence/absence: one including vertical cliffs and a second one, including moderately inclined cliffs, Posidonia meadows and detritic biogenic bottoms. Bath sponges occurred at a restricted number of stations and although in relatively low population densities, they revealed a sign of recovery after the devastating epidemic events. Higher stock availability was found for six biotechnologically promising species which were distributed all over the study area. The above results are encouraging for a future sustainable stock exploitation and open a new perspective for sponge mariculture in the area.

Commercial sponge fishing in Libya: Historical records, present status and perspectives

Natural bath sponges (genera Spongia and Hippospongia, Porifera, Demospongiae) have been harvested for millennia to be used as aids to beauty and body tools, in traditional and modern medicine as well as in painting. Recently, a series of severe epidemics have affected Mediterranean commercial sponges fostering the overexploitation of remaining fishing grounds. Furthermore, Mediterranean bath sponges attain the highest prices compared to Caribbean or Indo-Pacific ones but little or no correct information on origin is transferred to the final buyer. A complex network of re-selling activities and the lack of labelling make it almost impossible to track the pathway of sponge trade. Some of the finest Mediterranean natural bath sponges come from Libya. Nevertheless, little information on Libyan sponge banks and trade have been available mostly given the former international ban. Under an Italian–Libyan joint-project it was possible to assess the past and present situation of sponge fishing in Libya, roughly covering a period of 150 years. After rather low production in years 1860–1879, average crop exceeded 40 t/year between 1880 and 1929. The peak was recorded in years 1920–1929 (almost 70 t/year on average). Today Libyan sponge fishery and trade are mostly confined to the eastern area of the country. Less than 10 t/year are currently harvested. According to a preliminary SCUBA diving survey along the Libyan coasts, sponges belonging to the order Dictyoceratida appear to be the most conspicuous sessile invertebrates in the investigated areas. Here, sponges belonging to the genera Ircinia and Sarcotragus (commonly defined “wild sponges” with no commercial value) appear to be more abundant than those belonging to the genera Spongia and Hippospongia. Sustainable approaches to the exploitation of this valuable natural resource such as sponge farming are proposed and discussed.

Bath sponge aquaculture in Torres Strait, Australia: Effect of explant size, farming method and the environment on culture success

Global demand for bath sponges far exceeds supply and cannot be met by harvesting natural populations. Aquaculture is considered the only method that could supply sufficient and sustainable quantities of bath sponges and it may also be a suitable industry for remote coastal communities such as in Torres Strait, Australia. A series of farming experiments were done in Torres Strait using the common bath sponge Coscinoderma sp. to establish commercially viable culture procedures. The first experiment compared several farming methods and found that mesh panels promoted greatest sponge growth and survival, probably because they cause minimal tissue damage. Using mesh panels, a subsequent experiment examined the importance of farming site and season of transplant. Sponge growth and survival were similar between the three farming sites, while growth was highest for explants transplanted at the end of winter. These explants doubled in size on average in 6 months. The final experiment examined the optimal explant size to transplant and found that “medium sized” explants (∼ 100 cm 3) have good growth and survival, and permit high explant production from a given amount of sponge biomass. This study has identified good farming procedures, and coupled with the high growth rates of Coscinoderma sp., it suggests that bath sponge aquaculture in Torres Strait will be a viable industry.

Development of a new protocol for testing bath sponge quality

Due to the diverse morphological variation that occurs in sponges between and within species, protocols for quantitative quality testing are required to select sponges and optimise conditions for the aquaculture of high quality bath sponges. A protocol was developed to assess the quality of sponges using mechanical engineering techniques. It quantified the physical properties of sponges (density, fibre width, fibre length, absorbency, and water retention efficiency) and their mechanical properties (firmness, compression modulus, compressive strength, tensile strength, elastic limit, elastic strain, modulus of elasticity, and modulus of resilience). To demonstrate these methods and provide a relative comparison, quality was measured for Rhopaloeides odorabile and Coscinoderma sp. and three commercial species, Hippospongia lachne, Spongia 1, and Spongia 2. There were significant differences between species for all quality parameters creating a unique profile for each species. R. odorabile was the firmest (37.8 ± 4.3 kPa), strongest (157.4 ± 17.3 kPa), and most rigid (838.7 ± 53.5 kPa) species tested, while Coscinoderma sp. was one of the softest sponges (7.3 ± 1.1 kPa) and had the highest elastic energy (30.5 ± 3.5 kJ/m 3) and water retention efficiency (40.1 ± 1.4%) of all the species. Of the commercial species, H. lachne was the softest (3.2 ± 0.3 kPa), weakest (36.3 ± 3.1 kPa), and most absorbent sponge (31.0 ± 1.1), while Spongia 1 and Spongia 2 had intermediate quality characteristics for all measured parameters. These tests enable scientifically rigorous comparisons of quality between and within species regardless of origin or post-harvest treatment. Comparisons between species may be used to select species for aquaculture and as a marketing tool to promote aquaculture products for specific applications. Within species testing will allow quantification of differences in quality caused by genetic or environmental factors.

A Superficial Overview of Detergency

An introduction to a study of detergency is based on the role played by surface-active agents, that is, surfactants. Typical concepts of surface chemistry such as the work of adhesion, Young and Young–Dupré equations, or the spreading coefficient are used to explain the mechanisms involved in the removal of both liquid and particulate dirt. The role of emulsions, micelles, and lather is also analyzed. By means of physicochemical arguments, this article justifies the use of bath sponges, explains how washing machines work, or why it is easier to do the washing up if the dishes have been previously immersed in water. The article also includes general considerations about the nature of the surfactants used in commercial products. It will provide instructors and students with an interest in surface chemistry a link between theoretical principles and practical explanations of everyday activities.

Rearing performance of Spongia officinalis on suspended ropes off the Southern Italian Coast (Central Mediterranean Sea)

The availability of bath sponges has been recently reduced due to the depletion of natural banks due to the high fishing pressure together with some local epidemic events. At present, the commercial supply is far below the demand. The main purpose of this work was to estimate the rearing performance of Spongia officinalis var. adriatica, one of the most common Mediterranean commercial sponges, testing two different variants of culture on suspended ropes: a horizontal system placed close to the seabed, and a vertical system extended along the water column. The trials were carried out in Southern Italy (Ionian coast of Apulia, Central Mediterranean) from April 1997 to April 2000. Wild specimens of sponge were cut into pieces of different weight to test possible differences in growth and survival. During the study period, both systems resisted deterioration due to water movement and other ecological factors. In general, the growth performance (average weight, specific growth rate) did not significantly vary between the cultivation systems, nor were statistical differences in growth detected between the cuttings of different initial size. The mean growth observed was rather variable among sponge cuttings, even considering the same rearing condition and size range. The measured variations of hydrological parameters did not seem to affect survival, growth performance, or reproductive activity, which was detected almost all year round. Larger explants (about 50 g in wet weight) reached the commercial size after three years of rearing, thus identifying this initial size as the most suitable for cultivation purposes. At the end of the study period, the survival rate was 75%, with a more apparent decrease during the first year of rearing.