Bioactive compounds and antioxidant activity during ripening of Malpighia glabra fruits.

Malpighia glabra (Malpighiaceae) is a cherry fruit popularly known as acerola or West Indian cherry, with nutraceuticals in each ripening stage. The changes in the phytoconstituents, pigments, sugars, organic acids, and antioxidants were investigated during the fruit ripening and expressed in fresh weight (FW). Gentisic acid was present in the highest concentration in IMGL fruits (11.43 mg/100 g), which was reduced to 0.362 mg/100 g over-ripening. The major flavonoid present was epicatechin, and the concentration increased from 2.11 mg/100 g in immature green large (IMGL) fruits to 19.52 mg/100 g in ripe fruits. Ascorbic acid was the most abundant organic acid present, and the highest concentration was found in the IMGL fruits (2030 mg/100 g). Fructose and galactose were found in the highest concentrations in overripe fruits (2290 mg/100 g and 1460 mg/100 g, respectively). The IMGL fruits showed the highest total antioxidant activity of 5.48% and 5.34% ascorbic acid equivalent in methanolic and aqueous extracts, respectively. Mineral quantification showed that the fruits were rich in potassium and calcium (150.43 and 12.90 mg/100 g, respectively). This study could identify the appropriate stage of acerola fruit for developing functional foods with maximum utilization of phytoconstituents in all stages.

Structure-based screening of natural product libraries in search of potential antiviral drug-leads as first-line treatment to COVID-19 infection.

The study focuses on identifying and screening natural products (NPs) based on their structural similarities with chemical drugs followed by their possible use in first-line treatment to COVID-19 infection. In the present study, the in-house natural product libraries, consisting of 26,311 structures, were screened against potential targets of SARS-CoV-2 based on their structural similarities with the prescribed chemical drugs. The comparison was based on molecular properties, 2 and 3-dimensional structural similarities, activity cliffs, and core fragments of NPs with chemical drugs. The screened NPs were evaluated for their therapeutic effects based on their predicted in-silico pharmacokinetic and pharmacodynamics properties, binding interactions with the appropriate targets, and structural stability of the bound complex using molecular dynamics simulations. The study yielded NPs with significant structural similarities to synthetic drugs currently used to treat COVID-19 infections. The study proposes the probable biological action of the selected NPs as Anti-retroviral protease inhibitors, RNA-dependent RNA polymerase inhibitors, and viral entry inhibitors.

Biosynthesis and regulation of anthocyanin pathway genes.

Anthocyanins are the phenolic compounds responsible for coloring pigments in fruits and vegetables. Anthocyanins offer a wide range of health benefits to human health. Their scope has expanded dramatically in the past decade, making anthocyanin control, influx, and outflow regulation fascinating for many researchers. The main culprit is anthocyanin stability and concentration form, which demands novel ways because these are critical in the food industry. This review aims to examine anthocyanin synthesis via triggering transcription genes that code for anthocyanin-producing enzymes. The balance between production and breakdown determines anthocyanin accumulation. Thus, increasing the anthocyanin content in food requires the stability of molecules in the vacuolar lumen, the pigment fading process, and a better understanding of the mechanism. The promising option is biosynthesis by metabolically engineered microorganisms with a lot of success. This study aims to look into and evaluate the existing literature on anthocyanin production, namely the biosynthesis of anthocyanin pathway genes, production by microbial cell factories, and the regulatory factors that can modulate the production of anthocyanins. Understanding these mechanisms will provide new biotechnological approaches.Key points• Factors affecting the regulation of anthocyanins• Focus on degradation, biosynthesis pathway genes, and alternative systems for the production of anthocyanins• Microbial cell factories can be used to produce large amounts of anthocyanins.

Chemometric evaluation of functional components and anti-quorum sensing activity of mulberry leaves from Indian cultivars: a potential contribution to the food industry.

BACKGROUND: Potential use of many native, easily available vegetal materials for human consumption and value addition is not well recognized. Mulberry, being a traditional industrial crop rich in nutrients and nutraceuticals can be of great importance for the food industry. However, mulberry leaves are mainly being utilized in sericulture and are not exploited for their functional components. Thus, the selection of promising mulberry cultivars, rich in bioactive compounds, like resveratrol and 1-deoxynojirimycin, increase their potential use in functional foods. RESULTS: Chlorogenic acid, myricetin and kaempferol were the major polyphenols present in the nine selected cultivars, in the range 0.001-0.086, 0.003-0.079 and 0.003-0.163 g kg-1 fresh weight (FW), respectively. Protocatechuic acid, epicatechin and rutin were predominantly present in cultivars V-1, G-2 and ML (0.103, 0.080 and 0.121 g kg-1 FW, respectively). Similarly, resveratrol and 1-deoxynojirimycin were highest in cultivars ML and K-2 (0.078 and 0.079 g kg-1 FW, respectively). Leaf extracts of cultivars G-2 and ML were able to effectively inhibit the violacein production with 64.08% and 70.04%, respectively at the concentration of 6 mg mL-1 presumably due to a higher content of polyphenols. Chemometric evaluation of chromatographic data showed the intraspecific variability and secondary metabolite co-existence in different cultivars. CONCLUSIONS: Considering phytoconstituents, cultivars G-2, ML, K-2 and V-1 could contribute efficiently to the rational utilization of mulberry in agro-food industries. Furthermore, cultivars G-2 and ML leaves can be a new source of quorum sensing inhibitory agents. © 2021 Society of Chemical Industry.

Impact of the COVID-19 pandemic on the surveillance, prevention and control of antimicrobial resistance: a global survey.

OBJECTIVES: The COVID-19 pandemic has had a substantial impact on health systems. The WHO Antimicrobial Resistance (AMR) Surveillance and Quality Assessment Collaborating Centres Network conducted a survey to assess the effects of COVID-19 on AMR surveillance, prevention and control. METHODS: From October to December 2020, WHO Global Antimicrobial Resistance and Use Surveillance System (GLASS) national focal points completed a questionnaire, including Likert scales and open-ended questions. Data were descriptively analysed, income/regional differences were assessed and free-text questions were thematically analysed. RESULTS: Seventy-three countries across income levels participated. During the COVID-19 pandemic, 67% reported limited ability to work with AMR partnerships; decreases in funding were frequently reported by low- and middle-income countries (LMICs; P < 0.01). Reduced availability of nursing, medical and public health staff for AMR was reported by 71%, 69% and 64%, respectively, whereas 67% reported stable cleaning staff availability. The majority (58%) reported reduced reagents/consumables, particularly LMICs (P < 0.01). Decreased numbers of cultures, elective procedures, chronically ill admissions and outpatients and increased ICU admissions reported could bias AMR data. Reported overall infection prevention and control (IPC) improvement could decrease AMR rates, whereas increases in selected inappropriate IPC practices and antimicrobial prescribing could increase rates. Most did not yet have complete data on changing AMR rates due to COVID-19. CONCLUSIONS: This was the first survey to explore the global impact of COVID-19 on AMR among GLASS countries. Responses highlight important actions to help ensure that AMR remains a global health priority, including engaging with GLASS to facilitate reliable AMR surveillance data, seizing the opportunity to develop more sustainable IPC programmes, promoting integrated antibiotic stewardship guidance, leveraging increased laboratory capabilities and other system-strengthening efforts.

Mass testing after a single suspected or confirmed case of COVID-19 in London care homes, April-May 2020: implications for policy and practice.

INTRODUCTION: Previous investigations have identified high rates of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among residents and staff in care homes reporting an outbreak of coronavirus disease 2019 (COVID-19). We investigated care homes reporting a single suspected or confirmed case to assess whether early mass testing might reduce risk of transmission during the peak of the pandemic in London. METHODS: Between 18 and 27 April 2020, residents and staff in care homes reporting a single case of COVID-19 to Public Health England had a nasal swab to test for SARS-CoV-2 infection by reverse transcription polymerase chain reaction and subsequent whole-genome sequencing. Residents and staff in two care homes were re-tested 8 days later. RESULTS: Four care homes were investigated. SARS-CoV-2 positivity was 20% (65/333) overall, ranging between 3 and 59%. Among residents, positivity ranged between 3 and 76% compared with 3 and 40% in staff. Half of the SARS-CoV-2-positive residents (23/46, 50%) and 63% of staff (12/19) reported symptoms within 14 days before or after testing. Repeat testing 8 days later in two care homes with the highest infection rates identified only two new cases. Genomic analysis demonstrated a small number of introduction of the virus into care homes, and distinct clusters within three of the care homes. CONCLUSIONS: We found extensive but variable rates of SARS-CoV-2 infection among residents and staff in care homes reporting a single case of COVID-19. Although routine whole-home testing has now been adopted into practice, care homes must remain vigilant and should be encouraged to report a single suspected case, which should trigger appropriate outbreak control measures.

Identification and Characterization of Polyphenols from Carissa spinarum Fruit and Evaluation of Their Antioxidant and Anti-quorum Sensing Activity.

Quorum sensing controls bacterial virulence through signaling molecules, which plays a vital role in managing foodborne pathogens that cause food spoilage and human infections. Though many synthetic compounds have been used to control infection, antibiotic resistance has become a global issue. Targeting the bacterial quorum sensing using the bioactive compounds could be an alternative strategy to combat their resistance. In this context, polyphenols from an unexplored unripe and ripe fruits of Carissa spinarum were evaluated for anti-quorum sensing activity. The study aimed at determining nutritional, phytochemical composition, and polyphenol profiling to evaluate their antioxidant potential of the fruit. Furthermore, the violacein inhibition, anti-biofilm, and effect on the motility of foodborne pathogens were also studied. The phytochemical content of C. spinarum fruit showed the phenolic and flavonoid content 273.20 mg GAE/100 g and 453.78 mg QE/100 g fresh weight , respectively, in ripe fruit. HPLC characterization of fruit extracts showed high content of syringic acid, resveratrol, and quercetin in ripe, whereas it showed epicatechin and gentisic acid in unripe fruit. The antioxidant activity of the ripe fruit extract exhibited a higher potential to scavenge DPPH radicals with IC50 4.69 mg/mL. Further, the anti-quorum sensing activity was higher in ripe fruit extract at 1.8 mg/mL inhibited with 78.65% violacein production in Chromobacterium violaceum, swimming motility, and biofilm formation in Pseudomonas aeruginosa and Yersinia enterocolitica (66.25% and 59.36% respectively at 1.2 mg/mL). Hence C. spinarum fruit bioactive could be a natural plant source for anti-quorum sensing activity to manage foodborne pathogens over synthetic compounds.

Pleiotropic nature of curcumin in targeting multiple apoptotic-mediated factors and related strategies to treat gastric cancer: A review.

Gastric cancer (GC) is one of the major reasons for cancer-associated death and exhibits the second-highest mortality rate worldwide. Several advanced approaches have been designed to treat GC; however, these strategies possess many innate complications. In view of this, the upcoming research relying on natural products could result in designing potential anticancer agents with fewer side effects. Curcumin, isolated from the rhizomes of Curcuma longa L. has several medicinal properties like antiinflammatory, antioxidant, antiapoptotic, antitumor, and antimetastatic. Such pleiotropic nature of curcumin impedes the invasion and proliferation of GC by targeting several oncogenic factors like p23, human epidermal factor receptor2 including Helicobacter pylori. The side effect of chemotherapy, that is, chemotherapeutic resistance and radiotherapy could be reduced combination therapy of curcumin. Moreover, the photodynamic therapy of curcumin destroys the cancer cells without affecting normal cells. However, further more potential studies are required to establish the potent efficacy of curcumin in the treatment of GC. The current review details the anticancer activities of curcumin and related strategies which could be employed to treat GC with additional focus on its inhibitory properties against viability, proliferation, and migration of GC cells through cell cycle arrest and stimulation by apoptosis-mediated factors.

Physicochemical Composition and Characterization of Bioactive Compounds of Mulberry (Morus indica L.) Fruit During Ontogeny.

Mulberry fruit is well recognized as one of the richest sources of bioactive compounds. We investigated the physicochemical composition and characterized the bioactive compounds during different ripening stages of mulberry (Morus indica) fruit and evaluated their anti-quorum sensing activity on Chromobacterium violaceum. The proximate components such as carbohydrates, proteins and lipids were found to be high in the ripe fruit compared to unripe and mid-ripe fruit. The ripe fruit contained higher content of total phenolics and flavonoids (336.05 and 282.55 mg/100 g fresh weight (FW), respectively). Epicatechin and resveratrol were the major polyphenols detected in the fruit with the range 5.13-19.46 and 4.07-14.45 mg/100 g FW, respectively. Chlorogenic acid and myricetin were predominant in the unripe and mid-ripe fruit (7.14 and 1.84 mg/100 g FW, respectively). The fruit was found to be an excellent source of anti-diabetic compound 1-deoxynojirimycin. The highest content of 1-deoxynojirimycin was present in the mid-ripe fruit, with a content of 2.91 mg/100 g FW. Furthermore, fruit extracts exhibited anti-quorum sensing activity against Chromobacterium violaceum by effectively inhibiting violacein production. Ripe fruit extracts showed the highest activity of 76.30% at 1 mg/mL and thus, could be used as a potent anti-quorum sensing agent. The results could be promising in the selection of appropriate developmental stages for M. indica fruit commercial exploitation in the food formulations rich in potential health components.

Evaluation of diosgenin content from eleven different Indian varieties of fenugreek and fenugreek leaf powder fortified bread.

The present study designed to establish the diosgenin profile from eleven different Indian varieties of fenugreek, and subsequently develop powder from the best stage and variety to prepare diosgenin fortified bread. The seeds, sprouts and leaves of different fenugreek varieties were analyzed for the diosgenin using HPLC. The content of phenolics and flavonoids also estimated and assessed for its antioxidant capacity using phosphomolybdate, DPPH and FRAP. Among eleven varieties screened for diosgenin and the other compounds, tender leaf of Kasuri methi (KS) variety showed the highest content of diosgenin (466.89 ± 0.32 mg/100 g FW), phenolics (58.54 ± 2.70 mg/100 g FW) and flavonoids (1104.16 ± 43.70 mg/100 g FW) followed by Pusa Early Bunching (PEB) (444.18 ± 0.36 mg/100 g FW) and Early Bunching (EB) (409.45 ± 0.42 mg/100 g FW). Among three stages, seeds found to be a better total antioxidant, DPPH scavenging, and reducing ability. Further, based on the results, bread fortified with 1.5% KS leaf powder is found to be optimal which also has significant diosgenin content (268.91 mg/100 g DW). And the effect of KS leaf powder on amylograph and farinograph characteristics of wheat flour and quality characteristics of bread showed promising results of acceptance.

Invasive Group B Streptococcus Infections in Adults, England, 2015-2016.

During 2015-2016, a total of 3,156 episodes of invasive group B Streptococcus (iGBS) infection in adults (>15 years of age) were recorded in England, corresponding to an annual incidence of 3.48/100,000 population. iGBS incidence was highest in older patients and women of childbearing age. The 493 pregnancy-related iGBS episodes correspond to a rate of 1.34/10,000 live births. In adults up to 60-69 years of age and in pregnant women, iGBS incidence increased with higher levels of socioeconomic deprivation. Hospital admissions associated with iGBS were predominantly emergency admissions (73% [2,260/3,099]); only 7% of nonpregnancy iGBS diagnoses were made >48 hours after admission. Underlying conditions were highly prevalent in nonpregnant adult case-patients, including cardiovascular (57%), lung (43%), and kidney (45%) disease and diabetes (40%). Post-iGBS episode 30-day and 12-month all-cause mortality rates in nonpregnant adults were 12% and 24%, respectively. No pregnancy-related iGBS deaths were identified.

Evaluation of Various Drying Methods on Bioactives, Ascorbic Acid and Antioxidant Potentials of Talinum triangulare L., foliage.

The aim of this study was to assess the efficiency of different drying methods (room, sun, oven, microwave, cross-flow, infra-red, dehumidifier, and freeze-drying) on maximum retention of the nutritional and bioactive compounds profiling of Talinum triangulare, which is a less-known perishable leafy-vegetable. The evaluation of various drying methods is to learn the best appropriate strategy for a post-harvest drying method for retaining all the potential benefits with minor loss. Microwave and freeze-dried samples held the maximum ascorbic acid quantified by HPLC with 1.36 and 1.11 g/100 g DW, respectively. The main carotenoid compounds identified were violaxanthin, lutein, zeaxanthin, ß-carotene isomers, trans-ß-carotene, and cis-ß-carotenes. Gallic, protocatechuic, catechin, para-coumaric, ferulic, rutin, trans-cinnamic, and quercetin are the significant phenolics and flavonoids identified and quantified by liquid chromatography. The efficiency of different solvents on bioactive extractions uncovered that the methanol and 80% aqueous ethanol were good for retention of total phenolics, total flavonoids, and antioxidant compounds, which was affirmed through phosphomolybdate, DPPH, and FRAP assays. Dried T. triangulare foliage could be productively utilized as a promising raw material for food and pharma businesses because of its rich bioactive composition.

Antimicrobial stewardship: an evaluation of structure and process and their association with antimicrobial prescribing in NHS hospitals in England.

BACKGROUND: Rigorous antimicrobial stewardship programmes (ASPs) are an essential strategy against antimicrobial resistance. OBJECTIVES: To evaluate and score ASPs in acute English NHS hospitals and determine association of ASP scores with antimicrobial prescribing. METHODS: ASP structure and process were evaluated through an online survey in 148/152 acute hospitals in 2017. Scores were assigned to quality indicators based on resource- and labour-intensiveness, and their association with total and modified WHO-categorized 'Access', 'Watch' and 'Reserve' (AwaRe) prescribing was analysed. RESULTS: The survey response rate was 97% with 78% of trusts submitting antimicrobial prescribing data. Over 80% of ASPs contained stewardship teams, policies and access to outpatient parenteral antimicrobial therapy, whilst less than 50% scored well for leadership or funding. High process performance was observed for antimicrobial pre-authorization, prescribing review and feedback, restricted susceptibility reporting, antimicrobial consumption monitoring, adherence to guidelines and junior doctor training. Low process attainment included education of senior prescribers and lack of resistance surveillance data distribution. Between 2016 and 2017, there was no difference in total trust prescribing (P = 0.117) although carbapenem prescribing fell (incidence rate ratio = 0.93, 95% CI 0.88-0.98) in non-teaching hospitals; 'Watch' prescribing also increased for specialist hospitals (OR = 1.10, 95% CI 1.01-1.20), as did 'Reserve' category prescribing in teaching (OR = 1.58, 95% CI 1.23-3.02) and specialist hospitals (OR = 3.09, 95% CI 2.02-4.74). A high process score was associated with lower 'Reserve' prescribing (OR = 0.82, 95% CI 0.67-1.01). CONCLUSIONS: All responding trusts had established ASPs. The association of a scoring system with total and 'AWaRe' prescribing to assess effectiveness of ASPs merits further study.

Harnessing alternative sources of antimicrobial resistance data to support surveillance in low-resource settings.

One of the most pressing challenges facing the global surveillance of antimicrobial resistance (AMR) is the generation, sharing, systematic analysis and dissemination of data in low-resource settings. Numerous agencies and initiatives are working to support the development of globally distributed microbiology capacity, but the routine generation of a sustainable flow of reliable data will take time to establish before it can deliver a clinical and public health impact. By contrast, there are a large number of pharma- and academia-led initiatives that have generated a wealth of data on AMR and drug-resistant infections in low-resource settings, together with high-volume data generation by private laboratories. Here, we explore how untapped sources of data could provide a short-term solution that bridges the gap between now and the time when routine surveillance capacity will have been established and how this could continue to support surveillance efforts in the future. We discuss the benefits and limitations of data generated by these sources, the mechanisms and barriers to making this accessible and how academia and pharma might support the development of laboratory and analytical capacity. We provide key actions that will be required to harness these data, including: a mapping exercise; creating mechanisms for data sharing; use of data to support national action plans; facilitating access to and use of data by the WHO Global Antimicrobial Resistance Surveillance System; and innovation in data capture, analysis and sharing.

Atheroprotective effect of novel peptides from Porphyridium purpureum in RAW 264.7 macrophage cell line and its molecular docking study.

OBJECTIVE: To explore the atherogenic foam cell prevention efficiency of two dipeptides purified from Porphyridium purpureum on RAW 264.7 cell line and to study its molecular interaction through molecular docking. RESULT: P. purpureum consists of 29.9% protein and 2.98% phycoerythrin on a dry weight basis. The two dipeptides namely of Histidine-Glutamic acid (HE) and Glycine-Proline (GP) isolated from the total protein and purified phycoerythrin of P. purpureum respectively, were evaluated for atherogenic foam cell prevention capacity in RAW 264.7 cell line. The IC5O values of peptides were found to be 91.2 ± 1.81 µg/ml (GP), 103.3 ± 4.8 µg/ml (HE) in MTT assay. The two peptides reduce the foam cell formation, intracellular lipid accumulation (cholesterol and triglycerides) and the secretion of TNF-α and IL-6 which are inflammatory cytokines in RAW 264.7 cell line at non-cytotoxic concentrations. A molecular interaction study proposed the binding pose for GP and HE peptides targeting the scavenging receptors CD36, SRA1, and Map Kinase p38 (a protein mediator). CONCLUSIONS: The cell line and molecular docking study indicated that among the two dipeptides, peptide GP has the highest atherogenic foam cell prevention efficiency.

Carbapenemase-producing Enterobacteriaceae in the UK: a national study (EuSCAPE-UK) on prevalence, incidence, laboratory detection methods and infection control measures.

OBJECTIVES: To estimate UK prevalence and incidence of clinically significant carbapenemase-producing Enterobacteriaceae (CPE), and to determine epidemiological characteristics, laboratory methods and infection prevention and control (IPC) measures in acute care facilities. METHODS: A 6 month survey was undertaken in November 2013-April 2014 in 21 sentinel UK laboratories as part of the European Survey on Carbapenemase-Producing Enterobacteriaceae (EuSCAPE) project. Up to 10 consecutive, non-duplicate, clinically significant and carbapenem-non-susceptible isolates of Escherichia coli or Klebsiella pneumoniae were submitted to a reference laboratory. Participants answered a questionnaire on relevant laboratory methods and IPC measures. RESULTS: Of 102 isolates submitted, 89 (87%) were non-susceptible to ≥1 carbapenem, and 32 (36%) were confirmed as CPE. CPE were resistant to most antibiotics, except colistin (94% susceptible), gentamicin (63%), tigecycline (56%) and amikacin (53%). The prevalence of CPE was 0.02% (95% CI = 0.01%-0.03%). The incidence of CPE was 0.007 per 1000 patient-days (95% CI = 0.005-0.010), with north-west England the most affected region at 0.033 per 1000 patient-days (95% CI = 0.012-0.072). Recommended IPC measures were not universally followed, notably screening high-risk patients on admission (applied by 86%), using a CPE 'flag' on patients' records (70%) and alerting neighbouring hospitals when transferring affected patients (only 30%). Most sites (86%) had a laboratory protocol for CPE screening, most frequently using chromogenic agar (52%) or MacConkey/CLED agars with carbapenem discs (38%). CONCLUSIONS: The UK prevalence and incidence of clinically significant CPE is currently low, but these MDR bacteria affect most UK regions. Improved IPC measures, vigilance and monitoring are required.

Fermentation induced changes in bioactive properties of wine from Phyllanthus with respect to atherosclerosis.

Wine was prepared from three varieties of Phyllanthus viz., P. emblica (wild and cultivated) and P. acidus. Among the wines prepared, cultivated Emblica wine had the highest total phenolic (11.02 µg gallic acid equivalent/ml) and flavonoid (59.46 µg quercetin equivalent/ml) content. Further gallic acid, syringic acid, protocatechuic acid and caffeic acid were present in higher amounts in wine from the cultivated variety compared to other wines. HPLC analysis showed that in juice of the cultivated variety, gallic acid and coumaric acid were found in higher amounts than that in the corresponding wine. Antioxidant assays, LDL oxidation prevention, foam cell prevention and nitrite scavenging activities (cell lines) were found to be highest in cultivated Emblica juice and wine with an activity of 15 µg/ml and 14 µg/ml (nitrite assay) and 108.649 µg ascorbic acid equivalent/mg and 321.622 µg ascorbic acid equivalent /mg (total antioxidant capacity) respectively. CD36 expression was reduced and ABCA1 expression was increased to the highest extent by the cultivated Emblica wine and juice. Further, antioxidant activity was seen to increase during the course of fermentation. Sensory analysis showed that cultivated Emblica wine was sweeter compared to the other wines.

London 2012 Olympic and Paralympic Games: public health surveillance and epidemiology.

Mass gatherings are regarded as potential risks for transmission of infectious diseases, and might compromise the health system of countries in which they are hosted. The evidence for increased transmission of infectious diseases at international sporting mass gatherings that attract many visitors from all over the world is not clear, and the evidence base for public health surveillance, epidemiology, and response at events such as the Olympics is small. However, infectious diseases are a recognised risk, and public health planning is, and should remain, a crucial part of the overall planning of sporting events. In this Series paper, we set out the planning and the surveillance systems that were used to monitor public health risks during the London 2012 Olympic and Paralympic Games in the summer of 2012, and draw attention to the public health issues-infectious diseases and chemical, radiation, and environmental hazards-that arose. Although the absolute risk of health-protection problems, including infectious diseases, at sporting mass gatherings is small, the need for reassurance of the absence of problems is higher than has previously been considered; this could challenge conventional public health surveillance systems. Recognition of the limitations of health-surveillance systems needs to be part of the planning for future sporting events.

Effect of different drying methods on chlorophyll, ascorbic acid and antioxidant compounds retention of leaves of Hibiscus sabdariffa L.

BACKGROUND: Use of the indigenous, easily accessible leafy vegetable roselle (Hibiscus sabdariffa L.) for value addition is gaining impetus as its nutritive and nutraceutical compounds are exposed by investigations. Being a perishable, storage is challenging, hence different methods of drying have been an attractive alternative for its postharvest usage in foods without much compromising its quality and antioxidant potential. RESULTS: Room- and freeze-dried samples were found to have best quality in terms of colour, total flavonoid content (18.53 ± 2.39 and 18.66 ± 1.06 g kg(-1) respectively), total phenolic content (17.76 ± 1.93 and 18.91 ± 0.48 g kg(-1)), chlorophyll content (1.59 ± 0.001 and 1.55 ± 0.001 g kg(-1)) and ascorbic acid content (11.11 ± 1.04 and 8.92 ± 0.94 g kg(-1)) compared with those subjected to infrared, crossflow, microwave, oven or sun drying. Samples treated by room and freeze drying retained maximum antioxidant potential as shown by the phosphomolybdate method and the 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging activity and ferric-reducing antioxidant power assays. Cold water and hot water extracts showed significantly higher total phenolic content and total antioxidant activity owing to the greater solubility of phenolics and destruction of cellular components in polar solvents than in organic solvents. CONCLUSION: The data obtained show the potential for retaining quality parameters of roselle leaf under suitable drying methods.